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Sample records for differentiating giardia lamblia

  1. An atypical proprotein convertase in Giardia lamblia differentiation.

    Science.gov (United States)

    Davids, B J; Gilbert, M A; Liu, Q; Reiner, D S; Smith, A J; Lauwaet, T; Lee, C; McArthur, A G; Gillin, F D

    2011-02-01

    Proteolytic activity is important in the lifecycles of parasites and their interactions with hosts. Cysteine proteases have been best studied in Giardia, but other protease classes have been implicated in growth and/or differentiation. In this study, we employed bioinformatics to reveal the complete set of putative proteases in the Giardia genome. We identified 73 peptidase homologs distributed over 5 catalytic classes in the genome. Serial analysis of gene expression of the G. lamblia lifecycle found thirteen protease genes with significant transcriptional variation over the lifecycle, with only one serine protease transcript upregulated late in encystation. The translated gene sequence of this encystation-specific transcript was most similar to eukaryotic subtilisin-like proprotein convertases (SPC), although the typical catalytic triad was not identified. Epitope-tagged gSPC protein expressed in Giardia under its own promoter was upregulated during encystation with highest expression in cysts and it localized to encystation-specific secretory vesicles (ESV). Total gSPC from encysting cells produced proteolysis in gelatin gels that co-migrated with the epitope-tagged protease in immunoblots. Immuno-purified gSPC also had gelatinase activity. To test whether endogenous gSPC activity is involved in differentiation, trophozoites and cysts were exposed to the specific serine proteinase inhibitor 4-(2-aminoethyl)-benzenesulfonyl fluoride hydrochloride (AEBSF). After 21 h encystation, a significant decrease in ESV was observed with 1mM AEBSF and by 42 h the number of cysts was significantly reduced, but trophozoite growth was not inhibited. Concurrently, levels of cyst wall proteins 1 and 2, and AU1-tagged gSPC protein itself were decreased. Excystation of G. muris cysts was also significantly reduced in the presence of AEBSF. These results support the idea that serine protease activity is essential for Giardia encystation and excystation. Copyright © 2010 Elsevier B

  2. Selective condensation drives partitioning and sequential secretion of cyst wall proteins in differentiating Giardia lamblia.

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    Christian Konrad

    2010-04-01

    Full Text Available Controlled secretion of a protective extracellular matrix is required for transmission of the infective stage of a large number of protozoan and metazoan parasites. Differentiating trophozoites of the highly minimized protozoan parasite Giardia lamblia secrete the proteinaceous portion of the cyst wall material (CWM consisting of three paralogous cyst wall proteins (CWP1-3 via organelles termed encystation-specific vesicles (ESVs. Phylogenetic and molecular data indicate that Diplomonads have lost a classical Golgi during reductive evolution. However, neogenesis of ESVs in encysting Giardia trophozoites transiently provides basic Golgi functions by accumulating presorted CWM exported from the ER for maturation. Based on this "minimal Golgi" hypothesis we predicted maturation of ESVs to a trans Golgi-like stage, which would manifest as a sorting event before regulated secretion of the CWM. Here we show that proteolytic processing of pro-CWP2 in maturing ESVs coincides with partitioning of CWM into two fractions, which are sorted and secreted sequentially with different kinetics. This novel sorting function leads to rapid assembly of a structurally defined outer cyst wall, followed by slow secretion of the remaining components. Using live cell microscopy we find direct evidence for condensed core formation in maturing ESVs. Core formation suggests that a mechanism controlled by phase transitions of the CWM from fluid to condensed and back likely drives CWM partitioning and makes sorting and sequential secretion possible. Blocking of CWP2 processing by a protease inhibitor leads to mis-sorting of a CWP2 reporter. Nevertheless, partitioning and sequential secretion of two portions of the CWM are unaffected in these cells. Although these cysts have a normal appearance they are not water resistant and therefore not infective. Our findings suggest that sequential assembly is a basic architectural principle of protective wall formation and requires

  3. Prevalence of Entamoeba histolytica , Giardia lamblia , and ...

    African Journals Online (AJOL)

    Introduction: The intestinal protozoa Entamoeba histolytica, Giardia lamblia, and Cryptosporidium spp. are the causative agents of giardiasis, amebiasis, and cryptosporidiosis, respectively. Adequate knowledge of the geographical distribution of parasites and the demographic variables that influence their prevalence is ...

  4. Azasterols impair Giardia lamblia proliferation and induces encystation

    International Nuclear Information System (INIS)

    Maia, Claudia; Attias, Marcia; Urbina, Julio; Gilbert, Ian; Magaraci, Filippo; Souza, Wanderley de

    2007-01-01

    The effects of sterol biosynthesis inhibitors on growth and fine structure of Giardia lamblia P1 strain cultures were analyzed. Azasterols demonstrated high efficacy in killing cells. The IC 50 values for 22,26-azasterol and 24(R,S),25-epiminolanosterol were 7 μM and 170 nM, respectively. Morphological analysis showed that azasterols induced changes in G. lamblia ultrastructure. The most significant alterations were: (a) considerable increase of the size of the peripheral vesicles, which are part of the parasite endosomal-lysosomal system; (b) appearance of autophagosomal structures; and (c) induction of differentiation, followed by an abnormal enlargement of encystation secretory vesicles. We propose that azasterols are effective chemotherapeutic drugs against Giardia lamblia in vitro and may have another target in cells besides sterol biosynthesis

  5. Genomic minimalism in the early diverging intestinal parasite Giardia lamblia.

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    Morrison, Hilary G; McArthur, Andrew G; Gillin, Frances D; Aley, Stephen B; Adam, Rodney D; Olsen, Gary J; Best, Aaron A; Cande, W Zacheus; Chen, Feng; Cipriano, Michael J; Davids, Barbara J; Dawson, Scott C; Elmendorf, Heidi G; Hehl, Adrian B; Holder, Michael E; Huse, Susan M; Kim, Ulandt U; Lasek-Nesselquist, Erica; Manning, Gerard; Nigam, Anuranjini; Nixon, Julie E J; Palm, Daniel; Passamaneck, Nora E; Prabhu, Anjali; Reich, Claudia I; Reiner, David S; Samuelson, John; Svard, Staffan G; Sogin, Mitchell L

    2007-09-28

    The genome of the eukaryotic protist Giardia lamblia, an important human intestinal parasite, is compact in structure and content, contains few introns or mitochondrial relics, and has simplified machinery for DNA replication, transcription, RNA processing, and most metabolic pathways. Protein kinases comprise the single largest protein class and reflect Giardia's requirement for a complex signal transduction network for coordinating differentiation. Lateral gene transfer from bacterial and archaeal donors has shaped Giardia's genome, and previously unknown gene families, for example, cysteine-rich structural proteins, have been discovered. Unexpectedly, the genome shows little evidence of heterozygosity, supporting recent speculations that this organism is sexual. This genome sequence will not only be valuable for investigating the evolution of eukaryotes, but will also be applied to the search for new therapeutics for this parasite.

  6. Molecular identification of Giardia lamblia isolates from adult human ...

    African Journals Online (AJOL)

    ARL

    2013-02-27

    Feb 27, 2013 ... Giardia lamblia is a flagellated protozoa that infects the intestinal tract of a wide range of mammalian hosts, including both wild and domestic animals as well as humans. Two genotypes A and B are commonly reported among humans. The purpose of this study was to investigate the genotypes of G.

  7. Comparison of Giardia lamblia and Giardia muris cyst inactivation by ozone.

    Science.gov (United States)

    Finch, G R; Black, E K; Labatiuk, C W; Gyürék, L; Belosevic, M

    1993-11-01

    Inactivation of Giardia lamblia and Giardia muris cysts was compared by using an ozone demand-free 0.05 M phosphate buffer in bench-scale batch reactors at 22 degrees C. Ozone was added to each trial from a concentrated stock solution for contact times of 2 and 5 min. The viability of the control and treated cysts was evaluated by using the C3H/HeN mouse and Mongolian gerbil models for G. muris and G. lamblia, respectively. The resistance of G. lamblia to ozone was not significantly different from that of G. muris under the study conditions, contrary to previously reported data that suggested G. lamblia was significantly more sensitive to ozone than G. muris was. The simple Ct value for 2 log unit inactivation of G. lamblia was 2.4 times higher than the Ct value recommended by the Surface Water Treatment Rule.

  8. Effect of Chlorine on Giardia lamblia Cyst Viability

    OpenAIRE

    Jarroll, Edward L.; Bingham, Alan K.; Meyer, Ernest A.

    1981-01-01

    The effect of chlorine concentration on Giardia lamblia cyst viability was tested under a variety of conditions. The ability of Giardia cysts to undergo excystation was used as the criterion of viability. The experimental variables employed included temperature (25, 15, and 5°C), pH (6, 7, and 8), chlorine-cyst contact time (10, 30, and 60 min), and chlorine concentration (1 to 8 mg/liter). In the pH range studied, cyst survival generally was observed to increase as buffer pH increased. Water...

  9. Development of functional gastrointestinal disorders after Giardia lamblia infection

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    Hanevik Kurt

    2009-04-01

    Full Text Available Abstract Background Functional gastrointestinal disorders (FGID may occur following acute gastroenteritis. This long-term complication has previously not been described after infection with the non-invasive protozoan Giardia lamblia. This study aims to characterize persistent abdominal symptoms elicited by Giardia infection according to Rome II criteria and symptoms scores. Methods Structured interview and questionnaires 12–30 months after the onset of Giardia infection, and at least 6 months after Giardia eradication, among 82 patients with persisting abdominal symptoms elicited by the Giardia infection. All had been evaluated to exclude other causes. Results We found that 66 (80.5% of the 82 patients had symptoms consistent with irritable bowel syndrome (IBS and 17 (24.3% patients had functional dyspepsia (FD according to Rome II criteria. IBS was sub classified into D-IBS (47.0%, A-IBS (45.5% and C-IBS (7.6%. Bloating, diarrhoea and abdominal pain were reported to be most severe. Symptoms exacerbation related to specific foods were reported by 45 (57.7% patients and to physical or mental stress by 34 (44.7% patients. Conclusion In the presence of an IBS-subtype pattern consistent with post-infectious IBS (PI-IBS, and in the absence of any other plausible causes, we conclude that acute Giardia infection may elicit functional gastrointestinal diseases with food and stress related symptoms similar to FGID patients in general.

  10. Giardia lamblia infections in children in Ghana | Anim-Baidoo | Pan ...

    African Journals Online (AJOL)

    Results: prevalence of G. lamblia infections in diarrhea and non-diarrhea children were 5.8% and 5% respectively (P>0.5). Sequence data confirmed Giardia lamblia assemblage B as the predominant genotype in both diarrhoea and non-diarrhoea cases. There was no significant association of G. lamblia infection with any ...

  11. Intestinal mucus protects Giardia lamblia from killing by human milk.

    Science.gov (United States)

    Zenian, A J; Gillin, F D

    1987-02-01

    We have previously shown that nonimmune human milk kills Giardia lamblia trophozoites in vitro. Killing requires a bile salt and the activity of the milk bile salt-stimulated lipase. We now show that human small-intestinal mucus protects trophozoites from killing by milk. Parasite survival increased with mucus concentration, but protection was overcome during longer incubation times or with greater milk concentrations. Trophozoites preincubated with mucus and then washed were not protected. Protective activity was associated with non-mucin CsCl density gradient fractions. Moreover, it was heat-stable, non-dialyzable, and non-lipid. Whereas whole mucus inhibited milk lipolytic activity, protective mucus fractions did not inhibit the enzyme. Furthermore, mucus partially protected G. lamblia trophozoites against the toxicity of oleic acid, a fatty acid which is released from milk triglycerides by lipase. These studies show that mucus protects G. lamblia both by inhibiting lipase activity and by decreasing the toxicity of products of lipolysis. The ability of mucus to protect G. lamblia from toxic lipolytic products may help to promote intestinal colonization by this parasite.

  12. Role of nitric oxide and superoxide in Giardia lamblia killing

    Directory of Open Access Journals (Sweden)

    P.D. Fernandes

    1997-01-01

    Full Text Available Giardia lamblia trophozoites were incubated for 2 h with activated murine macrophages, nitric oxide (NO donors or a superoxide anion generator (20 mU/ml xanthine oxidase plus 1 mM xanthine. Activated macrophages were cytotoxic to Giardia trophozoites (~60% dead trophozoites. This effect was inhibited (>90% by an NO synthase inhibitor (200 µM and unaffected by superoxide dismutase (SOD, 300 U/ml. Giardia trophozoites were killed by the NO donors, S-nitroso-acetyl-penicillamine (SNAP and sodium nitroprusside (SNP in a dose-dependent manner (LD50 300 and 50 µM, respectively. A dual NO-superoxide anion donor, 3-morpholino-sydnonimine hydrochloride (SIN-1, did not have a killing effect in concentrations up to 1 mM. However, when SOD (300 U/ml was added simultaneously with SIN-1 to Giardia, a significant trophozoite-killing effect was observed (~35% dead trophozoites at 1 mM. The mixture of SNAP or SNP with superoxide anion, which yields peroxynitrite, abolished the trophozoite killing induced by NO donors. Authentic peroxynitrite only killed trophozoites at very high concentrations (3 mM. These results indicate that NO accounts for Giardia trophozoite killing and this effect is not mediated by peroxynitrite

  13. A real-time RT-PCR method to detect viable Giardia lamblia cysts in environmental waters.

    Science.gov (United States)

    Baque, Robert H; Gilliam, Amy O; Robles, Liza D; Jakubowski, Walter; Slifko, Theresa R

    2011-05-01

    Currently, USEPA Method 1623 is the standard assay used for simultaneous detection of Giardia cysts and Cryptosporidium oocysts in various water matrices. However, the method is unable to distinguish between species, genotype, or to assess viability. Therefore, the objective of the present study was to address the shortcomings of USEPA Method 1623 by developing a novel molecular-based method that can assess viability of Giardia cysts in environmental waters and identify genotypes that pose a human health threat (assemblage groups A and B). Primers and TaqMan(®) probes were designed to target the beta-giardin gene in order to discriminate among species and assemblages. Viability was determined by detection of de-novo mRNA synthesis after heat induction. The beta-giardin primer/probe sets were able to detect and differentiate between Giardia lamblia assemblages A and B, and did not detect Giardia muris (mouse species) or G. lamblia assemblages C, D, E and F (non-human), with the exception of Probe A which did detect G. lamblia assemblage F DNA. Additionally, DNA or cDNA of other waterborne organisms were not detected, suggesting that the method is specific to Giardia assemblages. Assay applicability was demonstrated by detection of viable G. lamblia cysts in spiked (assemblage B) and unspiked (assemblage A and B) reclaimed water samples. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Therapeutic enhancement of newly derived bacteriocins against Giardia lamblia.

    Science.gov (United States)

    Amer, Eglal I; Mossallam, Shereen F; Mahrous, Hoda

    2014-11-01

    Trials for identifying efficient anti-giardial agents are still ongoing. Nowadays, bacteriocins have attracted the attention as potential antimicrobial compounds. For the first time, the current study evaluated the therapeutic efficacy of bacteriocins derived from newly isolated Egyptian strains of probiotics Lactobacilli; L. acidophilus (P106) and L. plantarum (P164) against Giardia lamblia. Bacteriocins' efficacy was evaluated both in vitro; by growth inhibition and adherence assays, and in vivo; through estimation of parasite density, intestinal histopathological examination and ultrastructural analysis of Giardia trophozoites. In vivo bacteriocins' clinical safety was assessed. In vitro results proved that 50 µg of L. acidophilus bacteriocin induced reduction of the mean Giardia lamblia trophozoites by 58.3 ± 4.04%, while at lower concentrations of 10 and 20 µg of both L. acidophilus and L. plantarum, non significant reduction of the mean parasite density was achieved. In vitro trophozoites adherence was susceptible to the tested bacteriocins at all studied concentrations with variable degrees, while the highest adherence reduction was demonstrated using 50 µg of L acidophilus bacteriocin. In vivo, oral inoculation of 50 µg/mouse L. acidophilus bacteriocin for 5 successive days resulted in a noteworthy decline of the intestinal parasite density, along with amelioration of intestinal pathology of infected mice. Ultrastructural examination proved thatfive doses of L. acidophilus bacteriocin showed marked changes in cellular architecture of the trophozoites with evident disorganization of the cell membrane, adhesive disc and cytoplasmic components. This is the first reported study of the safe anti-giardial efficacy of L. acidophilus (P106) derived bacteriocin, hence highlighting its great promise as a potential therapeutic safe alternative to existing commercial drugs. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Ultrastructural observations on giardiasis in a mouse model. II. Endosymbiosis and organelle distribution in Giardia muris and Giardia lamblia.

    Science.gov (United States)

    Nemanic, P C; Owen, R L; Stevens, D P; Mueller, J C

    1979-08-01

    Ultrastructural observations of Giardia muris in a mouse model revealed endosymbiotic microbes not previously reported in Giardia. Endosymbionts 240--360 nm wide, 600--1,400 nm long, and with an internal structure similar to that of bacilli were not seen entering Giardia but were found and appeared to divide within Giardia. No evidence was found of digestion of the endosymbionts by the giardia host in either the trophozoite or the cyst form. Endosymbionts were concentrated centrally around the nuclear area and were uncommon in peripheral feeding regions. The same cellular organelles seen in G. muris were found in Giardia lamblia from human jejunal biopsy material, but no endosymbionts were identified in G. lamblia trophozoites from the seven patients examined. Endosymbionts within Giardia may be found to alter trophozoite pathogenicity, metabolism, range of infectivity, antigenic surface characteristics, and host specificity, as they do in other protozoa.

  16. Genotyping of Giardia lamblia isolates from humans in China and Korea using ribosomal DNA Sequences.

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    Yong, T S; Park, S J; Hwang, U W; Yang, H W; Lee, K W; Min, D Y; Rim, H J; Wang, Y; Zheng, F

    2000-08-01

    Genetic characterization of a total of 15 Giardia lamblia isolates, 8 from Anhui Province, China (all from purified cysts) and 7 from Seoul, Korea (2 from axenic cultures and 5 from purified cysts), was performed by polymerase chain reaction amplification and sequencing of a 295-bp region near the 5' end of the small subunit ribosomal DNA (eukaryotic 16S rDNA). Phylogenetic analyses were subsequently conducted using sequence data obtained in this study, as well as sequences published from other Giardia isolates. The maximum parsimony method revealed that G. lamblia isolates from humans in China and Korea are divided into 2 major lineages, assemblages A and B. All 7 Korean isolates were grouped into assemblage A, whereas 4 Chinese isolates were grouped into assemblage A and 4 into assemblage B. Two Giardia microti isolates and 2 dog-derived Giardia isolates also grouped into assemblage B, whereas Giardia ardeae and Giardia muris were unique.

  17. Detection and molecular characterisation of Giardia lamblia genotypes in Sharjah, United Arab Emirates.

    Science.gov (United States)

    ElBakri, Ali; Samie, Amidou; Bessong, Pascal; Potgieter, Natasha; Odeh, Ra'ed Abu

    2014-08-01

    No data are available on Giardia lamblia genotypes in the United Arab Emirates (UAE). This study aimed to identify G. lamblia from DNA extracted from human stool samples to gain information on its prevalence and to perform molecular analysis on isolates collected from expatriates from different localities residing in Sharjah, UAE. In total, 111 healthy expatriates residing in Sharjah were screened for G. lamblia using nested PCR amplification of the small subunit ribosomal RNA (ssu-rRNA) gene. Positive samples were genotyped using a nested PCR amplifying the triosephosphate isomerase (tpi) gene to differentiate between the two human assemblages (A and B). A subset of the PCR products (n=23) were sequenced and their phylogenetic relationships were determined. Of the 111 participants, 67 (60.4%) were identified as positive for the ssu-rRNA gene. When genotyped for the tpi gene, 18.9% (21/111) were of assemblage A, 17.1% (19/111) belonged to assemblage B and 5.4% (6/111) showed patterns compatible with mixed infections. A strong correlation between the presence of diarrhoea and assemblage B was observed (χ(2)=10.553; p=0.001). Moreover, an association was also observed between mixed infections (A+B) and diarrhoea (χ(2)=8.899; p=0.003). No correlation between age, gender and geographic origin of the infected individual was noted. Phylogenetic analysis showed three clusters for the tpi gene. No relationship between the clusters and the origin of samples was noted. This study is the first to determine the infection rate and genotypic composition of Giardia in Sharjah, UAE. © The Author 2014. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. T-cell-dependent control of acute Giardia lamblia infections in mice.

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    Singer, S M; Nash, T E

    2000-01-01

    We have studied immune mechanisms responsible for control of acute Giardia lamblia and Giardia muris infections in adult mice. Association of chronic G. lamblia infection with hypogammaglobulinemia and experimental infections of mice with G. muris have led to the hypothesis that antibodies are required to control these infections. We directly tested this hypothesis by infecting B-cell-deficient mice with either G. lamblia or G. muris. Both wild-type mice and B-cell-deficient mice eliminated the vast majority of parasites between 1 and 2 weeks postinfection with G. lamblia. G. muris was also eliminated in both wild-type and B-cell-deficient mice. In contrast, T-cell-deficient and scid mice failed to control G. lamblia infections, as has been shown previously for G. muris. Treatment of wild-type or B-cell-deficient mice with antibodies to CD4 also prevented elimination of G. lamblia, confirming a role for T cells in controlling infections. By infecting mice deficient in either alphabeta- or gammadelta-T-cell receptor (TCR)-expressing T cells, we show that the alphabeta-TCR-expressing T cells are required to control parasites but that the gammadelta-TCR-expressing T cells are not. Finally, infections in mice deficient in production of gamma interferon or interleukin 4 (IL-4) and mice deficient in responding to IL-4 and IL-13 revealed that neither the Th1 nor the Th2 subset is absolutely required for protection from G. lamblia. We conclude that a T-cell-dependent mechanism is essential for controlling acute Giardia infections and that this mechanism is independent of antibody and B cells.

  19. Detection of anti-Giardia lamblia serum antibody among children of day care centers

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    Guimarães Semíramis

    2002-01-01

    Full Text Available OBJETIVES: To detect anti-Giardia lamblia serum antibodies in healthy children attending public day care centers and to assess serological tests as tools for estimating the prevalence of G. lamblia in endemic areas. METHODS: Three separate stool specimens and filter paper blood samples were collected from 147 children ranging from 0 to 6 years old. Each stool sample was processed using spontaneous sedimentation and zinc sulfate flotation methods. Blood samples were tested by indirect immunofluorescence (IIF and enzyme-linked immunosorbent assay (ELISA for Giardia IgG. RESULTS AND CONCLUSIONS: Of 147 individuals tested, 93 (63.3% showed Giardia cysts in their feces. Using IIF and ELISA, serum antibodies were detected in 93 (63.3% and 100 (68% samples , respectively. Sensitivity of IIF and ELISA was 82% and 72%, respectively. However, ELISA revealed to be less specific (39% than IIF (70%. IIF also showed a higher concordance with microscopic examination than ELISA.

  20. An In Vitro Evaluation of Ozonized Organic Extra-Virgin Olive Oil on Giardia Lamblia Cysts.

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    Boland-Nazar, Najmeh Sadat; Eslamirad, Zahra; Sarmadian, Hossein; Ghasemikhah, Reza

    2016-11-01

    Giardia lamblia is a common intestinal parasite that has been reported all over the world. This study was conducted to evaluate the effect of ozonized organic extra-virgin olive oil on the cyst of G. lamblia . The olive oil was ozonized based on international standards and confirmed by the world health organization (WHO) at various times in a generator. The ozone concentration of olive oil was adjusted at 32, 64, 96, 128, 160 mg/g based on ozone absorption. Giardia lamblia cysts were isolated from heavily infected stool samples and the sucrose gradient flotation technique. Five groups of triple tubes containing Giardia cysts were exposed to olive oil with 32, 64, 96, 128, 160 ozone concentrations, and the sixth and seventh groups were exposed to non-ozonized olive oil and normal saline, respectively. The tubes were placed at room temperature, and every four hours, the mortality of the Giardia cysts was assessed. The results showed that the first five groups' mortality rate of Giardia cysts reached 100% in 100 hours. An increasing concentration of ozone in olive oil leads to an increase in the mortality rate of Giardia cysts. The results showed a significant difference in the mean time of the mortality in all the groups (P ≤ 0.05). Furthermore, the higher fatality effect of ozonized organic extra-virgin olive oil (Ozonized Olive Oil = OZO) was proved in comparison with metronidazole in vitro. We concluded that ozonized organic extra-virgin olive oil was a growth inhibitor of Giardia cysts, and concerning its compatibility with a biological system, it is recommended for further clinical trials.

  1. A comparison of the Giardia lamblia trophozoite and cyst transcriptome using microarrays

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    Widmer Giovanni

    2011-05-01

    Full Text Available Abstract Background Compared with many protists, Giardia lamblia has a simple life cycle alternating between cyst and trophozoite. Most research on the molecular biology of Giardia parasites has focused on trophozoites and the processes of excystation and encystation, whereas cysts have attracted less interest. The striking morphological differences between the dormant cyst and the rapidly dividing and motile trophozoite implies profound changes in the metabolism as the parasite encysts in the host's intestine and excysts upon ingestion by a new host. Results To investigate the magnitude of the transcriptional changes occurring during the G. lamblia life cycle we compared the transcriptome of G. lamblia trophozoites and cysts using single-color oligonucleotide microarrays. Cysts were found to possess a much smaller transcriptome, both in terms of mRNA diversity and abundance. Genes encoding proteins related to ribosomal functions are highly over-represented. The comparison of the transcriptome of cysts generated in culture or extracted from feces revealed little overlap, raising the possibility of significant biological differences between the two types of cysts. Conclusions The comparison of the G. lamblia cyst and trophozoite transcriptome showed that transcripts of most genes are present at a lower level in cysts. This global view of the cyst and trophozoite transcriptome complements studies focused on the expression of selected genes during trophozoite multiplication, encystation and excystation.

  2. (ELISA) kit for diagnosis copro-antigens of Giardia lamblia

    African Journals Online (AJOL)

    STORAGESEVER

    2010-08-02

    Aug 2, 2010 ... methods based on antigen scanning of parasites such as enzyme linked immunosorbent assay (ELISA), ... samples. To design this method, a pure antibody against parasite as well as an antibody conjugated to a ..... school children in Santiago, Chile by capture ELISA for the detection of fecal Giardia ...

  3. Development of a rapid HRM genotyping method for detection of dog-derived Giardia lamblia.

    Science.gov (United States)

    Tan, Liping; Yu, Xingang; Abdullahi, Auwalu Yusuf; Wu, Sheng; Zheng, Guochao; Hu, Wei; Song, Meiran; Wang, Zhen; Jiang, Biao; Li, Guoqing

    2015-11-01

    Giardia lamblia is a zoonotic flagellate protozoan in the intestine of human and many mammals including dogs. To assess a threat of dog-derived G. lamblia to humans, the common dog-derived G. lamblia assemblages A, C, and D were genotyped by high-resolution melting (HRM) technology. According to β-giardin gene sequence, the qPCR-HRM primers BG5 and BG7 were designed. A series of experiments on the stability, sensitivity, and accuracy of the HRM method were also tested. Results showed that the primers BG5 and BG7 could distinguish among three assemblages A, C, and D, which Tm value differences were about 1 °C to each other. The melting curves of intra-assay reproducibility were almost coincided, and those of inter-assay reproducibility were much the same shape. The lowest detection concentration was about 5 × 10(-6)-ng/μL sample. The genotyping results from 21 G. lamblia samples by the HRM method were in complete accordance with sequencing results. It is concluded that the HRM genotyping method is rapid, stable, specific, highly sensitive, and suitable for clinical detection and molecular epidemiological survey of dog-derived G. lamblia.

  4. Structure of the prolyl-tRNA synthetase from the eukaryotic pathogen Giardia lamblia

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    Larson, Eric T.; Kim, Jessica E.; Napuli, Alberto J.; Verlinde, Christophe L. M. J.; Fan, Erkang; Zucker, Frank H.; Van Voorhis, Wesley C.; Buckner, Frederick S.; Hol, Wim G. J.; Merritt, Ethan A., E-mail: merritt@u.washington.edu [Medical Structural Genomics of Pathogenic Protozoa, (United States); University of Washington, Seattle, WA 98195 (United States)

    2012-09-01

    The structure of Giardia prolyl-tRNA synthetase cocrystallized with proline and ATP shows evidence for half-of-the-sites activity, leading to a corresponding mixture of reaction substrates and product (prolyl-AMP) in the two active sites of the dimer. The genome of the human intestinal parasite Giardia lamblia contains only a single aminoacyl-tRNA synthetase gene for each amino acid. The Giardia prolyl-tRNA synthetase gene product was originally misidentified as a dual-specificity Pro/Cys enzyme, in part owing to its unexpectedly high off-target activation of cysteine, but is now believed to be a normal representative of the class of archaeal/eukaryotic prolyl-tRNA synthetases. The 2.2 Å resolution crystal structure of the G. lamblia enzyme presented here is thus the first structure determination of a prolyl-tRNA synthetase from a eukaryote. The relative occupancies of substrate (proline) and product (prolyl-AMP) in the active site are consistent with half-of-the-sites reactivity, as is the observed biphasic thermal denaturation curve for the protein in the presence of proline and MgATP. However, no corresponding induced asymmetry is evident in the structure of the protein. No thermal stabilization is observed in the presence of cysteine and ATP. The implied low affinity for the off-target activation product cysteinyl-AMP suggests that translational fidelity in Giardia is aided by the rapid release of misactivated cysteine.

  5. Dietary lipids containing gangliosides reduce Giardia muris infection in vivo and survival of Giardia lamblia trophozoites in vitro.

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    Suh, M; Belosevic, M; Clandinin, M T

    2004-06-01

    We examined whether a ganglioside supplemented diet affected the course of Giardia muris infection in mice and survival of Giardia lamblia trophozoites in vitro. Female CD-1 mice were fed 1 of 5 experimental diets: standard lab chow as a control diet; semi-synthetic diets containing 20% (w/w) triglyceride based on the fat composition of a conventional infant formula; triglyceride diet; triglyceride diet containing a low level of ganglioside (0.1% w/w); and triglyceride diet containing a high level of ganglioside (1.0% w/w of diet). After 2 weeks of feeding, mice were inoculated with G. muris by gastric intubation and fed the experimental diets during the course of the infection. Cysts released in the faeces and trophozoites present in the small intestine were enumerated at various times post-infection. The average cyst output and the number of trophozoites during the course of the infection in mice fed ganglioside-containing diet were found to be significantly lower (3-log10 reduction) compared to animals fed control diets. The results of in vitro growth studies indicated that gangliosides may be directly toxic to the parasites. Thus, gangliosides have a protective effect against G. muris infection in vivo and affect the survival of G. lamblia trophozoites in vitro.

  6. Genetic Variation of Giardia lamblia Isolates from Food-handlers in Kashan, Central Iran

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    Hossein HOOSHYAR

    2017-02-01

    Full Text Available Background: Based on genotyping study of human isolates of Giardia lamblia; humans are mainly infected by two assemblages A and B. The present study was carried out to determine the sub-assemblages of G. lamblia isolated from food handlers referred to Kashan health centers, central Iran, 2015.Methods: In this cross-sectional study, 3653 stool samples collected from food-handlers that annually refer to health center for getting a health certification and examined microscopically for G. lamblia cyst. Totally, 44 isolates were selected from 47 Giardia positive samples. Cysts were partially purified by the sucrose density gradient method. After freeze-thaw cycles, genomic DNA was extracted using QIAamp Stool Mini kit. A single step PCR-RFLP method was used to amplify a 458bp fragment at the glutamate dehydrogenase (gdh locus, restriction enzymes BspLI and RsaI were used for distinguish between genotypes A and B and their subgroups.Results: Of 44 isolates, 24(54.5% were sub-assemblage AII, 9(20.5% group B including 7(15.9% BIII and 2(4.6% BIV sub-assemblage and 11(25% isolates showed a mixed pattern of AII and B. Sub-assemblage AI was not detected in this study.Conclusion: The higher rate of sub-assemblage AII demonstrated an anthroponotic origin of the infection so infected food-handlers could directly transmit this protozoan to consumers via contaminated food and water. For finding of pattern of transmission and distribution of Giardia assemblages and sub-assemblage, more studies in human and animal population in different regions are necessary.

  7. Prevalence of Cryptosporidium and Giardia lamblia in Water Samples from Jeddah and Makkah Cities

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    Haytham Ahmed Zakai

    2014-01-01

    Full Text Available Water contamination by Giardia lamblia and Cryptosporidium is one of the causes of diarrhoea throughout the world.  A total of 161 and 84 samples were collected from Jeddah and Makkah cities, respectively.  Each sample was concentrated by double centrifugation and the sediment was examined as a wet smear and after staining with Trichrome and Kinyoun stains.  The results showed that 56 (35% and 1 (0.62 % samples of Jeddah were positive for the oocyst of Cryptosporidium and cyst of Giardia, whereas only 21 (25% and 2 (2.4 % samples of Makkah showed positivity for oocysts and cyst of these parasites. Overall Cryptosporidium contamination in bottled water and water from filling stations was 6.8% and 17.4%, respectively. Maximum contamination for Cryptosporidium was recorded in tap water which was 51% and 25% in Jeddah and Makkah, respectively.

  8. Curcumin alters the cytoskeleton and microtubule organization on trophozoites of Giardia lamblia.

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    Gutiérrez-Gutiérrez, Filiberto; Palomo-Ligas, Lissethe; Hernández-Hernández, José Manuel; Pérez-Rangel, Armando; Aguayo-Ortiz, Rodrigo; Hernández-Campos, Alicia; Castillo, Rafael; González-Pozos, Sirenia; Cortés-Zárate, Rafael; Ramírez-Herrera, Mario Alberto; Mendoza-Magaña, María Luisa; Castillo-Romero, Araceli

    2017-08-01

    Giardia lamblia is a worldwide protozoan responsible for a significant number of intestinal infections. There are several drugs for the treatment of giardiasis, but they often cause side effects. Curcumin, a component of turmeric, has antigiardial activity; however, the molecular target and mechanism of antiproliferative activity are not clear. The effects of curcumin on cellular microtubules have been widely investigated. Since tubulin is the most abundant protein in the cytoskeleton of Giardia, to elucidate whether curcumin has activity against the microtubules of this parasite, we treated trophozoites with curcumin and the cells were analyzed by scanning electron microscopy and confocal microscopy. Curcumin inhibited Giardia proliferation and adhesion in a time-concentration-dependent mode. The higher inhibitory concentrations of curcumin (3 and 15μM) disrupted the cytoskeletal structures of trophozoites; the damage was evident on the ventral disk, flagella and in the caudal region, also the membrane was affected. The immunofluorescence images showed altered distribution of tubulin staining on ventral disk and flagella. Additionally, we found that curcumin caused a clear reduction of tubulin expression. By docking analysis and molecular dynamics we showed that curcumin has a high probability to bind at the interface of the tubulin dimer close to the vinblastine binding site. All the data presented indicate that curcumin may inhibit Giardia proliferation by perturbing microtubules. Copyright © 2017. Published by Elsevier B.V.

  9. Crystal structures of carbamate kinase from Giardia lamblia bound with citric acid and AMP-PNP.

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    Kap Lim

    Full Text Available The parasite Giardia lamblia utilizes the L-arginine dihydrolase pathway to generate ATP from L-arginine. Carbamate kinase (CK catalyzes the last step in this pathway, converting ADP and carbamoyl phosphate to ATP and ammonium carbamate. Because the L-arginine pathway is essential for G. lamblia survival and absent in high eukaryotes including humans, the enzyme is a potential target for drug development. We have determined two crystal structures of G. lamblia CK (glCK with bound ligands. One structure, in complex with a nonhydrolyzable ATP analog, adenosine 5'-adenylyl-β,γ-imidodiphosphate (AMP-PNP, was determined at 2.6 Å resolution. The second structure, in complex with citric acid bound in the postulated carbamoyl phosphate binding site, was determined in two slightly different states at 2.1 and 2.4 Å resolution. These structures reveal conformational flexibility of an auxiliary domain (amino acid residues 123-170, which exhibits open or closed conformations or structural disorder, depending on the bound ligand. The structures also reveal a smaller conformational change in a region associated the AMP-PNP adenine binding site. The protein residues involved in binding, together with a model of the transition state, suggest that catalysis follows an in-line, predominantly dissociative, phosphotransfer reaction mechanism, and that closure of the flexible auxiliary domain is required to protect the transition state from bulk solvent.

  10. Detection and genotyping of Entamoeba histolytica, Entamoeba dispar, Giardia lamblia, and Cryptosporidium parvum by oligonucleotide microarray.

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    Wang, Zheng; Vora, Gary J; Stenger, David A

    2004-07-01

    Entamoeba histolytica, Giardia lamblia, and Cryptosporidium parvum are the most frequently identified protozoan parasites causing waterborne disease outbreaks. The morbidity and mortality associated with these intestinal parasitic infections warrant the development of rapid and accurate detection and genotyping methods to aid public health efforts aimed at preventing and controlling outbreaks. In this study, we describe the development of an oligonucleotide microarray capable of detecting and discriminating between E. histolytica, Entamoeba dispar, G. lamblia assemblages A and B, and C. parvum types 1 and 2 in a single assay. Unique hybridization patterns for each selected protozoan were generated by amplifying six to eight diagnostic sequences/organism by multiplex PCR; fluorescent labeling of the amplicons via primer extension; and subsequent hybridization to a set of genus-, species-, and subtype-specific covalently immobilized oligonucleotide probes. The profile-based specificity of this methodology not only permitted for the unequivocal identification of the six targeted species and subtypes, but also demonstrated its potential in identifying related species such as Cryptosporidium meleagridis and Cryptosporidium muris. In addition, sensitivity assays demonstrated lower detection limits of five trophozoites of G. lamblia. Taken together, the specificity and sensitivity of the microarray-based approach suggest that this methodology may provide a promising tool to detect and genotype protozoa from clinical and environmental samples.

  11. Giardia lamblia: identification of molecules that contribute to direct mast cell activation.

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    Muñoz-Cruz, Samira; Gomez-García, Argelia; Matadamas-Martínez, Félix; Alvarado-Torres, Juan A; Meza-Cervantez, Patricia; Arriaga-Pizano, Lourdes; Yépez-Mulia, Lilián

    2018-06-02

    Mast cells play a central role in the early clearance of the intestinal parasite Giardia lamblia. In a previous study, we reported that G. lamblia live trophozoites or trophozoite-derived total soluble extract induced direct activation (IgE-independent) of mast cells and release of IL-6 and TNF-α. To identify the Giardia molecules and the mast cell receptors involved in this activation, trophozoite-derived total soluble proteins separated into three fractions (F1-F3) were evaluated for its ability to activate mast cells in vitro. F2 activated mast cells in a greater extent than F1 and F3. Furthermore, F2 induced the release of IL-6 and TNF-α by mast cells. TLR2 and TLR4 expression increased slightly after mast cell stimulation with either F2 or total soluble extract; however, these receptors were not involved in F2 or total soluble extract-induced proinflammatory cytokine production. Proteins present in F2 as unique and high-intensity bands identified by liquid chromatography coupled with tandem mass spectrometry, include molecules with important biological activities such as enolase and arginine deiminase (ADI). Recombinant ADI and enolase were tested for their ability to activate mast cells, but only ADI induced a significant release of IL-6 and TNF-α. ADI product, citrulline but not ammonium, also induced mast cell release of TNF-α. Interestingly, recombinant ADI still stimulated the secretion of TNF-α by mast cells in a arginine-free medium, although in a lower extend that in the presence of arginine, indicating that either ADI itself can stimulate mast cells or through its metabolic product, citrulline.

  12. Bax function in the absence of mitochondria in the primitive protozoan Giardia lamblia.

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    Adrian B Hehl

    Full Text Available Bax-induced permeabilization of the mitochondrial outer membrane and release of cytochrome c are key events in apoptosis. Although Bax can compromise mitochondria in primitive unicellular organisms that lack a classical apoptotic machinery, it is still unclear if Bax alone is sufficient for this, or whether additional mitochondrial components are required. The protozoan parasite Giardia lamblia is one of the earliest branching eukaryotes and harbors highly degenerated mitochondrial remnant organelles (mitosomes that lack a genome. Here we tested whether human Bax expressed in Giardia can be used to ablate mitosomes. We demonstrate that these organelles are neither targeted, nor compromised, by Bax. However, specialized compartments of the regulated secretory pathway are completely ablated by Bax. As a consequence, maturing cyst wall proteins that are sorted into these organelles are released into the cytoplasm, causing a developmental arrest and cell death. Interestingly, this ectopic cargo release is dependent on the carboxy-terminal 22 amino acids of Bax, and can be prevented by the Bax-inhibiting peptide Ku70. A C-terminally truncated Bax variant still localizes to secretory organelles, but is unable to permeabilize these membranes, uncoupling membrane targeting and cargo release. Even though mitosomes are too diverged to be recognized by Bax, off-target membrane permeabilization appears to be conserved and leads to cell death completely independently of mitochondria.

  13. The effect of UV light on the inactivation of Giardia lamblia and Giardia muris cysts as determined by animal infectivity assay (P-2951-01).

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    Mofidi, Alexander A; Meyer, Ernest A; Wallis, Peter M; Chou, Connie I; Meyer, Barbara P; Ramalingam, Shivaji; Coffey, Bradley M

    2002-04-01

    This study measured the effect of germicidal ultraviolet (UV) light on Giardia lamblia and Giardia muris cysts, as determined by their infectivity in Mongolian gerbils and CD-1 mice, respectively. Reduction of cyst infectivity due to UV exposure was quantified by applying most probable number techniques. Controlled bench-scale, collimated-beam tests exposed cysts suspended in filtered natural water to light from a low-pressure UV lamp. Both G. lamblia and G. muris cysts showed similar sensitivity to UV light. At 3 mJ/cm2, a dose 10-fold lower than what large-scale UV reactors may be designed to provide, > 2-log10 (99 percent) inactivation was observed. These results, combined with previously published data showing other protozoa and bacteria have similar, high sensitivity to UV light, establish that UV disinfection of drinking water is controlled by viruses which may require over 10-fold more UV dose for the same level of control.

  14. Incidence of Giardia lamblia Subspecies by PCR-RFLP in Stool Specimens of Hospitalized Children at Urmia Mutahhari Hospital, West Azerbaijan Province, Iran.

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    Khosro Hazrati Tappeh

    2014-12-01

    Full Text Available Giardia lamblia is one of the most prevalent intestinal flagellate protozoa that infects a wide range of vertebrate hosts causing severe intestinal disorder in children.This study was performed to determine subspecies of G.lamblia by the PCR-RFLP method, targeting the glutamate dehydrogenase(gdhlocus, in hospitalized children at Urmia Mutahhari Hospital, West Azerbaijan Province,Iran and determining the infection transformational storages in this area.Overall, 720 stool specimens were collected from the hospitalized children, 34 samples were positive and Giardia cysts were detected under the microscope. Cysts were partially purified by the sucrose density gradient method and then washed with sterile distilled water to remove effectively the PCR inhibitors. Genomic DNA of G. lamblia isolates was extracted by freeze-thaw cycles followed by phenol/ chloroform/isoamyl alcohol method. The single step PCR-RFLP assay was used to differentiate the assemblages between A and B, which were found in humans. In this method, 432 bp expected size was amplified, and then for detection of subspecies, specific restriction RsaI and BspLI enzymes were used.Totally 34 samples were positive in terms of Giardia cyst out of 720 examined samples microscopically, so the parasite spread rate is reported 4.72%. Analysis PCR-RFLP on these samples revealed that 28 samples (93.3% have the genotype BIII and 2 samples (6.7% belong to the subgroup BIV.PCR-RFLP is a proper analytical method for determining the genotype among parasite types, using the glutamate dehydrogenizes zone's genes. Based on the results, an animal origin of infection cycle is suggested.

  15. An ancient spliceosomal intron in the ribosomal protein L7a gene (Rpl7a of Giardia lamblia

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    Gray Michael W

    2005-08-01

    Full Text Available Abstract Background Only one spliceosomal-type intron has previously been identified in the unicellular eukaryotic parasite, Giardia lamblia (a diplomonad. This intron is only 35 nucleotides in length and is unusual in possessing a non-canonical 5' intron boundary sequence, CT, instead of GT. Results We have identified a second spliceosomal-type intron in G. lamblia, in the ribosomal protein L7a gene (Rpl7a, that possesses a canonical GT 5' intron boundary sequence. A comparison of the two known Giardia intron sequences revealed extensive nucleotide identity at both the 5' and 3' intron boundaries, similar to the conserved sequence motifs recently identified at the boundaries of spliceosomal-type introns in Trichomonas vaginalis (a parabasalid. Based on these observations, we searched the partial G. lamblia genome sequence for these conserved features and identified a third spliceosomal intron, in an unassigned open reading frame. Our comprehensive analysis of the Rpl7a intron in other eukaryotic taxa demonstrates that it is evolutionarily conserved and is an ancient eukaryotic intron. Conclusion An analysis of the phylogenetic distribution and properties of the Rpl7a intron suggests its utility as a phylogenetic marker to evaluate particular eukaryotic groupings. Additionally, analysis of the G. lamblia introns has provided further insight into some of the conserved and unique features possessed by the recently identified spliceosomal introns in related organisms such as T. vaginalis and Carpediemonas membranifera.

  16. Giardia lamblia: a major parasitic cause of childhood diarrhoea in patients attending a district hospital in Ghana.

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    Nkrumah, Bernard; Nguah, Samuel Blay

    2011-08-22

    Acute childhood diarrhoea remains one of the leading causes of childhood morbidity and mortality in developing countries. The WHO has accordingly underlined the need for epidemiological surveys of infantile diarrhoea in all geographical areas. This study was conducted to determine the incidence of intestinal parasites among stool samples from children examined at a secondary health care facility in a rural area of Ghana. A retrospective study was conducted to investigate the incidence of intestinal parasites among children who had their stools examined at the Agogo Hospital laboratory. Stool microscopy results from January 2006 through May 2009 were obtained from archived records of the laboratory. Results for children less than 18 years were transcribed unto a standardized datasheet, entered into an electronic database designed using Microsoft® access 2007 and analyzed using Stata/SE11.1 statistical software. The incidences of the parasites were determined and presented with their Poisson exact 95% confidence intervals for the various ages. The median age of the 1080 children included in the study was 5 years (IQR: 2-12 years) with 51.9% being females. The overall incidence of all parasites was 114 per 1000 with Giardia lamblia being the most common (89.5%). Children aged less than a year had the lowest parasite incidence of 13 per 1000 with all being Giardia lamblia, while those aged 15-17 years had the highest of 169 per 1000. The incidence for Giardia lamblia only was lowest at 13 per 1000 for those under a year old, highest at 152 per 1000 for the 15-17 year group and 97 per 1000 for all ages combined. There was a significant rise in incidence of Giardia lamblia with age (Trend x2 = 18.6, p < 0.001). Five (4.3%) of the 118 positive stool samples had mixed parasites infection. Enterobius vermicularis, Taenia spp and Trichuris trichiura were not seen in any of the stool samples. Giardia lamblia is the most prevalent intestinal parasite in examined stool samples

  17. Identification and analysis of the RNA degrading complexes and machinery of Giardia lamblia using an in silico approach.

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    Williams, Christopher W; Elmendorf, Heidi G

    2011-11-29

    RNA degradation is critical to the survival of all cells. With increasing evidence for pervasive transcription in cells, RNA degradation has gained recognition as a means of regulating gene expression. Yet, RNA degradation machinery has been studied extensively in only a few eukaryotic organisms, including Saccharomyces cerevisiae and humans. Giardia lamblia is a parasitic protist with unusual genomic traits: it is binucleated and tetraploid, has a very compact genome, displays a theme of genomic minimalism with cellular machinery commonly comprised of a reduced number of protein components, and has a remarkably large population of long, stable, noncoding, antisense RNAs. Here we use in silico approaches to investigate the major RNA degradation machinery in Giardia lamblia and compare it to a broad array of other parasitic protists. We have found key constituents of the deadenylation and decapping machinery and of the 5'-3' RNA degradation pathway. We have similarly found that all of the major 3'-5' RNA degradation pathways are present in Giardia, including both exosome-dependent and exosome-independent machinery. However, we observe significant loss of RNA degradation machinery genes that will result in important differences in the protein composition, and potentially functionality, of the various RNA degradation pathways. This is most apparent in the exosome, the central mediator of 3'-5' degradation, which apparently contains an altered core configuration in both Giardia and Plasmodium, with only four, instead of the canonical six, distinct subunits. Additionally the exosome in Giardia is missing both the Rrp6, Nab3, and Nrd1 proteins, known to be key regulators of noncoding transcript stability in other cells. These findings suggest that although the full complement of the major RNA degradation mechanisms were present - and likely functional - early in eukaryotic evolution, the composition and function of the complexes is more variable than previously

  18. [Knowledge, perceptions and practice of dermatologists with respect to Giardia lamblia infection].

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    Iglesias Hernández, Tania; Almannoni, Saleh Ali; Rodríguez, Maria Elena; Sánchez Valdés, Lizet; Pupo, Deisy Martín; Manzur Katrib, Julián; Fonte Galindo, Luis

    2010-01-01

    to ascertain the level of knowledge, the perceptions and practice of dermatologists in the City of Havana with respect to Giardia lamblia infection. with prior informed consent given by the dermatologists from the City of Havana, 50 dermatologists- a number very close to the universe of these experts in the province- were administered a survey of their knowledge, perceptions and practice about this parasitosis. The survey was prepared in 4 phases; that is, interviews to physicians on diagnosis, treatment and control of giardiasis; drafting of a preliminary questionnaire based on the interview results; submission of this instruments to the experts, and finally its validation through its application to a small group of physicians. it was evinced that the dermatologists in the City of Havana had poor knowledge about giardiasis, particularly its cutaneous manifestations (out of 19 questions on cognitive aspects, the correct answer mean was 10,18), inadequate perceptions on this disease and practice was not good. with the aim of mitigating these difficulties, some academic intervention is needed to make emphasis on the formative aspects related to parasitic diseases in general and giardiasis in particular

  19. A Systematic Review and Meta-analysis of the Association Between Giardia lamblia and Endemic Pediatric Diarrhea in Developing Countries

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    Muhsen, Khitam; Levine, Myron M.

    2012-01-01

    We performed a systematic literature review and meta-analysis examining the association between diarrhea in young children in nonindustrialized settings and Giardia lamblia infection. Eligible were case/control and longitudinal studies that defined the outcome as acute or persistent (>14 days) diarrhea, adjusted for confounders and lasting for at least 1 year. Data on G. lamblia detection (mainly in stools) from diarrhea patients and controls without diarrhea were abstracted. Random effects model meta-analysis obtained pooled odds ratios (ORs) and 95% confidence intervals (CIs). Twelve nonindustrialized-setting acute pediatric diarrhea studies met the meta-analysis inclusion criteria. Random-effects model meta-analysis of combined results (9774 acute diarrhea cases and 8766 controls) yielded a pooled OR of 0.60 (95% CI, .38–.94; P = .03), indicating that G. lamblia was not associated with acute diarrhea. However, limited data suggest that initial Giardia infections in early infancy may be positively associated with diarrhea. Meta-analysis of 5 persistent diarrhea studies showed a pooled OR of 3.18 (95% CI, 1.50–6.76; P diarrhea in children in developing countries. PMID:23169940

  20. Modeling long-term host cell-Giardia lamblia interactions in an in vitro co-culture system.

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    Bridget S Fisher

    Full Text Available Globally, there are greater than 700,000 deaths per year associated with diarrheal disease. The flagellated intestinal parasite, Giardia lamblia, is one of the most common intestinal pathogens in both humans and animals throughout the world. While attached to the gastrointestinal epithelium, Giardia induces epithelial cell apoptosis, disrupts tight junctions, and increases intestinal permeability. The underlying cellular and molecular mechanisms of giardiasis, including the role lamina propria immune cells, such as macrophages, play in parasite control or clearance are poorly understood. Thus far, one of the major obstacles in ascertaining the mechanisms of Giardia pathology is the lack of a functionally relevant model for the long-term study of the parasite in vitro. Here we report on the development of an in vitro co-culture model which maintains the basolateral-apical architecture of the small intestine and allows for long-term survival of the parasite. Using transwell inserts, Caco-2 intestinal epithelial cells and IC-21 macrophages are co-cultured in the presence of Giardia trophozoites. Using the developed model, we show that Giardia trophozoites survive over 21 days and proliferate in a combination media of Caco-2 cell and Giardia medium. Giardia induces apoptosis of epithelial cells through caspase-3 activation and macrophages do not abrogate this response. Additionally, macrophages induce Caco-2 cells to secrete the pro-inflammatory cytokines, GRO and IL-8, a response abolished by Giardia indicating parasite induced suppression of the host immune response. The co-culture model provides additional complexity and information when compared to a single-cell model. This model will be a valuable tool for answering long-standing questions on host-parasite biology that may lead to discovery of new therapeutic interventions.

  1. Genome-wide computational identification of microRNAs and their targets in the deep-branching eukaryote Giardia lamblia.

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    Zhang, Yan-Qiong; Chen, Dong-Liang; Tian, Hai-Feng; Zhang, Bao-Hong; Wen, Jian-Fan

    2009-10-01

    Using a combined computational program, we identified 50 potential microRNAs (miRNAs) in Giardia lamblia, one of the most primitive unicellular eukaryotes. These miRNAs are unique to G. lamblia and no homologues have been found in other organisms; miRNAs, currently known in other species, were not found in G. lamblia. This suggests that miRNA biogenesis and miRNA-mediated gene regulation pathway may evolve independently, especially in evolutionarily distant lineages. A majority (43) of the predicted miRNAs are located at one single locus; however, some miRNAs have two or more copies in the genome. Among the 58 miRNA genes, 28 are located in the intergenic regions whereas 30 are present in the anti-sense strands of the protein-coding sequences. Five predicted miRNAs are expressed in G. lamblia trophozoite cells evidenced by expressed sequence tags or RT-PCR. Thirty-seven identified miRNAs may target 50 protein-coding genes, including seven variant-specific surface proteins (VSPs). Our findings provide a clue that miRNA-mediated gene regulation may exist in the early stage of eukaryotic evolution, suggesting that it is an important regulation system ubiquitous in eukaryotes.

  2. Human milk containing specific secretory IgA inhibits binding of Giardia lamblia to nylon and glass surfaces.

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    Samra, H K; Ganguly, N K; Mahajan, R C

    1991-06-01

    The effects of human milk, containing specific secretory IgA, on the adherence of Giardia lamblia trophozoites in the presence and in the absence of intestinal mucus in vitro were studied. It was found that the trophozoites treated with breast milk, containing specific secretory IgA to G. lamblia, showed a significant decrease (p less than 0.01) in adherence to nylon fibre columns and glass surfaces than did trophozoites treated with milk containing no SIgA antibodies. The adherence to glass surfaces was significantly more (p less than 0.01) in the presence of intestinal mucus than when the mucus was absent. Milk that did not contain specific secretory SIgA to G. lamblia did not decrease the adherence to glass surfaces either in the presence or in the absence of mucus. The fluorescence study revealed the binding of specific secretory IgA on the trophozoite surface. The results suggest that binding of SIgA antibodies in milk to G. lamblia trophozoites inhibits parasite adherence, thus protecting against this infection in breast-fed babies.

  3. A Multiplex PCR for Simultaneous Detection of Three Zoonotic Parasites Ancylostoma ceylanicum, A. caninum, and Giardia lamblia Assemblage A

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    Wei Hu

    2015-01-01

    Full Text Available Ancylostoma ceylanicum, A. caninum, and Giardia lamblia assemblage A are common intestinal parasites of dogs and cats; they can also infect humans, causing parasitic zoonoses. In this study, a multiplex PCR method was developed for simultaneous identification and detection of those three zoonotic parasites. Three pairs of specific primers were designed based on ITS sequence of A. ceylanicum and A. caninum and TPI gene of G. lamblia available in the GenBank. The multiplex PCR reaction system was established by optimizing the reaction condition, and a series of tests on the sensitivity, specificity, and clinical application were also conducted. Results showed that three target fragments were amplified specifically; the detection limit was 10 eggs for both A. ceylanicum and A. caninum, 72 pg DNA for G. lamblia. Of 112 clinical fecal samples, 34.8% and 17.8% samples were positive for A. caninum and A. ceylanicum, respectively, while only 2.7% samples were positive for G. lamblia assemblage A. It is concluded that the established multiplex PCR assay is a convenient, rapid, cost-effective, and high-efficiency method for molecular detection and epidemiological investigation of three zoonotic parasites.

  4. Localizing Proteins in Fixed Giardia lamblia and Live Cultured Mammalian Cells by Confocal Fluorescence Microscopy.

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    Nyindodo-Ogari, Lilian; Schwartzbach, Steven D; Skalli, Omar; Estraño, Carlos E

    2016-01-01

    Confocal fluorescence microscopy and electron microscopy (EM) are complementary methods for studying the intracellular localization of proteins. Confocal fluorescence microscopy provides a rapid and technically simple method to identify the organelle in which a protein localizes but only EM can identify the suborganellular compartment in which that protein is present. Confocal fluorescence microscopy, however, can provide information not obtainable by EM but required to understand the dynamics and interactions of specific proteins. In addition, confocal fluorescence microscopy of cells transfected with a construct encoding a protein of interest fused to a fluorescent protein tag allows live cell studies of the subcellular localization of that protein and the monitoring in real time of its trafficking. Immunostaining methods for confocal fluorescence microscopy are also faster and less involved than those for EM allowing rapid optimization of the antibody dilution needed and a determination of whether protein antigenicity is maintained under fixation conditions used for EM immunogold labeling. This chapter details a method to determine by confocal fluorescence microscopy the intracellular localization of a protein by transfecting the organism of interest, in this case Giardia lamblia, with the cDNA encoding the protein of interest and then processing these organisms for double label immunofluorescence staining after chemical fixation. Also presented is a method to identify the organelle targeting information in the presequence of a precursor protein, in this case the presequence of the precursor to the Euglena light harvesting chlorophyll a/b binding protein of photosystem II precursor (pLHCPII), using live cell imaging of mammalian COS7 cells transiently transfected with a plasmid encoding a pLHCPII presequence fluorescent protein fusion and stained with organelle-specific fluorescent dyes.

  5. Evaluation of four techniques for diagnosis of Giardia lamblia in children's stool from Belém city, Para State, Brazil

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    Machado, Ricardo Luiz Dantas; Figueredo, Maria Cristina; Frade, Amanda Farage; Kudó, Mônica Eriko; Silva Filho, Manoel Gomes; Póvoa, Marinete Marins

    2001-01-01

    Relatamos a comparação de quatro metodologias para o diagnóstico da Giardia lamblia em material fecal de crianças, Belém/PA. A Hematoxilina Férrica e o método direto apresentaram menor positividade, enquanto que o Método de Faust continua uma boa escolha para o diagnóstico e o Ensaio imunoenzimático melhora a qualidade da detecção deste parasito.We report the evaluation of four techniques for Giardia lamblia diagnosis in children's stool. The Iron haematoxilin staining and direct examination ...

  6. The detection of Giardia muris and Giardia lamblia cysts by immunofluorescence in animal tissues and fecal samples subjected to cycles of freezing and thawing.

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    Erlandsen, S L; Sherlock, L A; Bemrick, W J

    1990-04-01

    The effects of freezing and thawing on the detection of selected Giardia spp. cysts were investigated using immunofluorescence, bright field microscopy, and low voltage scanning electron microscopy (SEM). Giardia muris cysts were obtained from either animal carcasses, fecal pellets, or isolated cyst preparations, whereas Giardia lamblia cysts were isolated from fecal samples. These samples were stained using an immunofluorescence technique after 1-3 freezing (-16 C) and thawing (20 C) cycles. Cysts were detected successfully by immunofluorescence in all samples. However, in those samples subjected to freeze-thawing, the cyst walls often became distorted and then were not detectable by bright field microscopy. Low voltage SEM demonstrated that the filaments in the distorted cyst wall underwent rearrangements of interfilament spacing. Quantitation of cyst recovery after freezing and thawing demonstrated that a substantial loss occurred after 1 cycle of alternating temperature when low concentrations of cysts were used, but not with high concentrations of cysts. Cyst recovery, after 3 freezing and thawing cycles, was dramatically lowered irrespective of the initial cyst concentration. These results demonstrated that immunofluorescence was an effective technique for the detection of Giardia spp. cysts in frozen samples and would suggest that freezing and thawing of fecal samples could prevent the detection of cysts when only bright field microscopy was employed.

  7. Effect of olive leaf, Satureja khuzestanica, and Allium sativum extracts on Giardia lamblia cysts compared with metronidazole in vitro.

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    Fallahi, Sh; Rostami, A; Delfan, B; Pournia, Y; Rashidipour, M

    2016-12-01

    Giardia lamblia is one of the common causes of worldwide diarrhea in children. Appropriate medicinal treatment for giardiasis is available but there are some evidences of drug resistance, insufficient efficacy, and unpleasant side effects. In order to reach a more natural drug with suitable efficacy and the lowest side effects, the effects of the hydroalcoholic extracts of olive leaf, Satureja khuzestanica , and Allium sativum on G. lamblia cysts were evaluated in vitro, as well as antigiardial effect of the extracts was compared with metronidazole as the drug of choice. 2 and 5 mg of the plants extracts and powder of metronidazole 250 mg pills were added to 1 ml of G. lamblia cysts suspension (containing 5,000 cyst/ml normal saline), and the percentages of bioavailability of G. lamblia cysts were examined at the 2nd and 4th h after exposure and in 4 and 37 °C temperatures using eosin 0.1 % and a haemocytometer. The data were analyzed by multiway ANOVA test, Tukey's test, and the SPSS software, version 18. The examinations demonstrated that olive leaf extract had the most fatality rate on G. lamblia cysts in vitro (37.90 ± 7.01 %), followed by the extract of S. khuzestanica (32.52 ± 9.07 %). Metronidazole 250 mg pills had relatively effective fatality rate on G. lamblia cysts in vitro (28.75 ± 10.30 %), whereas A. sativum (garlic) had the lowest fatality effect on G. lamblia cysts in vitro (22.65 ± 10.47 %). With respect to higher fatality effect of olive leaf and S. khuzestanica extracts compared with metronidazole in vitro, these plants can be used as suitable candidates to make new antigiardial drugs with low side effects and without drug resistance in the treatment of giardiasis in children.

  8. Larrea tridentata: A novel source for anti-parasitic agents active against Entamoeba histolytica, Giardia lamblia and Naegleria fowleri.

    Directory of Open Access Journals (Sweden)

    Bharat Bashyal

    2017-08-01

    Full Text Available Protozoan parasites infect and kill millions of people worldwide every year, particularly in developing countries where access to clean fresh water is limited. Among the most common are intestinal parasites, including Giardia lamblia and Entamoeba histolytica. These parasites wreak havoc on the epithelium lining the small intestines (G. lamblia and colon (E. histolytica causing giardiasis and amebiasis, respectively. In addition, there are less common but far more deadly pathogens such as Naegleria fowleri that thrive in warm waters and infect the central nervous systems of their victims via the nasal passages. Despite their prevalence and associated high mortality rates, there remains an unmet need to identify more effective therapeutics for people infected with these opportunistic parasites. To address this unmet need, we have surveyed plants and traditional herbal medicines known throughout the world to identify novel antiparasitic agents with activity against G. lamblia, E. histolytica, and N. fowleri. Herein, we report Larrea tridentata, known as creosote bush, as a novel source for secondary metabolites that display antiparasitic activity against all three pathogens. This report also characterizes the lignan compound classes, nordihydroguairetic acid and demethoxyisoguaiacin, as novel antiparasitic lead agents to further develop more effective drug therapy options for millions of people worldwide.

  9. Larrea tridentata: A novel source for anti-parasitic agents active against Entamoeba histolytica, Giardia lamblia and Naegleria fowleri.

    Science.gov (United States)

    Bashyal, Bharat; Li, Linfeng; Bains, Trpta; Debnath, Anjan; LaBarbera, Daniel V

    2017-08-01

    Protozoan parasites infect and kill millions of people worldwide every year, particularly in developing countries where access to clean fresh water is limited. Among the most common are intestinal parasites, including Giardia lamblia and Entamoeba histolytica. These parasites wreak havoc on the epithelium lining the small intestines (G. lamblia) and colon (E. histolytica) causing giardiasis and amebiasis, respectively. In addition, there are less common but far more deadly pathogens such as Naegleria fowleri that thrive in warm waters and infect the central nervous systems of their victims via the nasal passages. Despite their prevalence and associated high mortality rates, there remains an unmet need to identify more effective therapeutics for people infected with these opportunistic parasites. To address this unmet need, we have surveyed plants and traditional herbal medicines known throughout the world to identify novel antiparasitic agents with activity against G. lamblia, E. histolytica, and N. fowleri. Herein, we report Larrea tridentata, known as creosote bush, as a novel source for secondary metabolites that display antiparasitic activity against all three pathogens. This report also characterizes the lignan compound classes, nordihydroguairetic acid and demethoxyisoguaiacin, as novel antiparasitic lead agents to further develop more effective drug therapy options for millions of people worldwide.

  10. Comparative characterisation of two nitroreductases from Giardia lamblia as potential activators of nitro compounds

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    Joachim Müller

    2015-08-01

    Full Text Available Giardia lamblia is a protozoan parasite that causes giardiasis, a diarrhoeal disease affecting humans and various animal species. Nitro drugs such as the nitroimidazole metronidazole and the nitrothiazolide nitazoxanide are used for treatment of giardiasis. Nitroreductases such as GlNR1 and GlNR2 may play a role in activation or inactivation of these drugs. The aim of this work is to characterise these two enyzmes using functional assays. For respective analyses recombinant analogues from GlNR1 and GlNR2 were produced in Escherichia coli. E. coli expressing GlNR1 and GlNR2 alone or together were grown in the presence of nitro compounds. Furthermore, pull-down assays were performed using HA-tagged GlNR1 and GlNR2 as baits. As expected, E. coli expressing GlNR1 were more susceptible to metronidazole under aerobic and semi-aerobic and to nitazoxanide under semi-aerobic growth conditions whereas E. coli expressing GlNR2 were susceptible to neither drug. Interestingly, expression of both nitroreductases gave the same results as expression of GlNR2 alone. In functional assays, both nitroreductases had their strongest activities on the quinone menadione (vitamin K3 and FAD, but reduction of nitro compounds including the nitro drugs metronidazole and nitazoxanide was clearly detected. Full reduction of 7-nitrocoumarin to 7-aminocoumarin was preferentially achieved with GlNR2. Pull-down assays revealed that GlNR1 and GlNR2 interacted in vivo forming a multienzyme complex. These findings suggest that both nitroreductases are multifunctional. Their main biological role may reside in the reduction of vitamin K analogues and FAD. Activation by GlNR1 or inactivation by GlNR2 of nitro drugs may be the consequence of a secondary enzymatic activity either yielding (GlNR1 or eliminating (GlNR2 toxic intermediates after reduction of these compounds.

  11. Clinical and microbiological features of dientamoebiasis in patients suspected of suffering from a parasitic gastrointestinal illness: a comparison of Dientamoeba fragilis and Giardia lamblia infections

    NARCIS (Netherlands)

    Vandenberg, Olivier; Peek, Ron; Souayah, Hichem; Dediste, Anne; Buset, Michel; Scheen, Robert; Retore, Patricia; Zissis, Georges; van Gool, Tom

    2006-01-01

    To describe the clinical and microbiological features of Dientamoeba fragilis and Giardia lamblia infected patients, and to analyze the genetic variation of D. fragilis strains. For a period of two years, all stool samples collected from patients suspected of having a parasitic gastrointestinal

  12. Click Chemistry-Facilitated Structural Diversification of Nitrothiazoles, Nitrofurans, and Nitropyrroles Enhances Antimicrobial Activity against Giardia lamblia

    Science.gov (United States)

    Kim, Wan Jung; Korthals, Keith A.; Li, Suhua; Le, Christine; Kalisiak, Jarosław; Sharpless, K. Barry; Fokin, Valery V.; Miyamoto, Yukiko

    2017-01-01

    ABSTRACT Giardia lamblia is an important and ubiquitous cause of diarrheal disease. The primary agents in the treatment of giardiasis are nitroheterocyclic drugs, particularly the imidazoles metronidazole and tinidazole and the thiazole nitazoxanide. Although these drugs are generally effective, treatment failures occur in up to 20% of cases, and resistance has been demonstrated in vivo and in vitro. Prior work had suggested that side chain modifications of the imidazole core can lead to new effective 5-nitroimidazole drugs that can combat nitro drug resistance, but the full potential of nitroheterocycles other than imidazole to yield effective new antigiardial agents has not been explored. Here, we generated derivatives of two clinically utilized nitroheterocycles, nitrothiazole and nitrofuran, as well as a third heterocycle, nitropyrrole, which is related to nitroimidazole but has not been systematically investigated as an antimicrobial drug scaffold. Click chemistry was employed to synthesize 442 novel nitroheterocyclic compounds with extensive side chain modifications. Screening of this library against representative G. lamblia strains showed a wide spectrum of in vitro activities, with many of the compounds exhibiting superior activity relative to reference drugs and several showing >100-fold increase in potency and the ability to overcome existing forms of metronidazole resistance. The majority of new compounds displayed no cytotoxicity against human cells, and several compounds were orally active against murine giardiasis in vivo. These findings provide additional impetus for the systematic development of nitroheterocyclic compounds with nonimidazole cores as alternative and improved agents for the treatment of giardiasis and potentially other infectious agents. PMID:28396548

  13. Hydrologic and Vegetative Removal of Cryptosporidium parvum, Giardia lamblia, and Toxoplasma gondii Surrogate Microspheres in Coastal Wetlands

    Science.gov (United States)

    Hogan, Jennifer N.; Daniels, Miles E.; Watson, Fred G.; Oates, Stori C.; Miller, Melissa A.; Conrad, Patricia A.; Shapiro, Karen; Hardin, Dane; Dominik, Clare; Melli, Ann; Jessup, David A.

    2013-01-01

    Constructed wetland systems are used to reduce pollutants and pathogens in wastewater effluent, but comparatively little is known about pathogen transport through natural wetland habitats. Fecal protozoans, including Cryptosporidium parvum, Giardia lamblia, and Toxoplasma gondii, are waterborne pathogens of humans and animals, which are carried by surface waters from land-based sources into coastal waters. This study evaluated key factors of coastal wetlands for the reduction of protozoal parasites in surface waters using settling column and recirculating mesocosm tank experiments. Settling column experiments evaluated the effects of salinity, temperature, and water type (“pure” versus “environmental”) on the vertical settling velocities of C. parvum, G. lamblia, and T. gondii surrogates, with salinity and water type found to significantly affect settling of the parasites. The mesocosm tank experiments evaluated the effects of salinity, flow rate, and vegetation parameters on parasite and surrogate counts, with increased salinity and the presence of vegetation found to be significant factors for removal of parasites in a unidirectional transport wetland system. Overall, this study highlights the importance of water type, salinity, and vegetation parameters for pathogen transport within wetland systems, with implications for wetland management, restoration efforts, and coastal water quality. PMID:23315738

  14. Mucosal delivery of a transmission-blocking DNA vaccine encoding Giardia lamblia CWP2 by Salmonella typhimurium bactofection vehicle.

    Science.gov (United States)

    Abdul-Wahid, Aws; Faubert, Gaétan

    2007-12-05

    In this study, we investigated the use of Salmonella typhimurium (STM1 strain) as a bactofection vehicle to deliver a transmission-blocking DNA vaccine (TBDV) plasmid to the intestinal immune system. The gene encoding the full length cyst wall protein-2 (CWP2) from Giardia lamblia was subcloned into the pCDNA3 mammalian expression vector and stably introduced into S. typhimurium STM1. Eight-week-old female BALB/c mice were orally immunized every 2 weeks, for a total of three immunizations. Vaccinated and control mice were sacrificed 1 week following the last injection. Administration of the DNA vaccine led to the production of CWP2-specific cellular immune responses characterized by a mixed Th1/Th2 response. Using ELISA, antigen-specific IgA and IgG antibodies were detected in intestinal secretions. Moreover, analysis of sera demonstrated that the DNA immunization also stimulated the production of CWP2-specific IgG antibodies that were mainly of the IgG2a isotype. Finally, challenge infection with live Giardia muris cysts revealed that mice receiving the CWP2-encoding DNA vaccine were able to reduce cyst shedding by approximately 60% compared to control mice. These results demonstrate, for the first time, the development of parasite transmission-blocking immunity at the intestinal level following the administration of a mucosal DNA vaccine delivered by S. typhimurium STM1.

  15. Association between Whipple's disease and Giardia lamblia infection Asociación de enfermedad de Whipple e infección por Giardia lamblia

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    J. A. Gil Ruiz

    2005-07-01

    Full Text Available Whipple'disease is mainly characterized by affecting the digestive system, although it can be a multisystemic process with different clinical symptoms. The bacillus causing the disease has been isolated and cultivated in 2000 and the genome sequence has been recently analyzed in 2003, which means new perspectives for its diagnosis and treatment. Giardiasis is an infestation caused by a protozoo and may cause a malabsorption syndrome or run in a subclinic way. The case of a middle-aged male is described, who after a three-year period of migratory arthralgias, showed weight loss, diarrheas and abdominal pain, being diagnosed of Giardiasis, and after the persistent symptoms and a number of studies, was diagnosed with Whipple disease. Nineteen cases of Giardia-Whipple coinfection have been described in the literature, but the reason of this association has not been found yet. The discussion on whether there is an alteration in the inmunitary system which facilitates infections or, the development of an infection lead to the other one, goes on.La enfermedad de Whipple se caracteriza por afectar principalmente al aparato digestivo, aunque puede ser un proceso multisistémico con variadas manifestaciones clínicas. En el año 2000 se ha conseguido aislar y cultivar el bacilo causante y recientemente, en el 2003, se ha analizado la secuencia completa del genoma, lo que supone nuevas perspectivas para el diagnóstico y el tratamiento. La giardiasis es una infección originada por un protozoo que puede evolucionar de forma subclínica o dar lugar a un síndrome de malabsorción. Describimos el caso de un paciente varón de mediana edad, que tras un periodo de tres años de artralgias migratorias en articulaciones periféricas, presentó un cuadro de pérdida de peso, con aumento del número de deposiciones y molestias abdominales siendo diagnosticado de Giardiasis y ante la persistencia de los síntomas y la posterior realización de diferentes estudios

  16. Prevalence of Cryptosporidium parvum/hominis, Entamoeba histolytica and Giardia lamblia among Young Children with and without Diarrhea in Dar es Salaam, Tanzania.

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    Marit G Tellevik

    Full Text Available Although enteroparasites are common causes of diarrheal illness, few studies have been performed among children in Tanzania. This study aimed to investigate the prevalence of Cryptosporidium parvum/hominis, Entamoeba histolytica and Giardia lamblia among young children in Dar es Salaam, Tanzania, and identify risk factors for infection.We performed an unmatched case-control study among children 12 months (P = 0.003; OR = 3.5; 95% CI: 1.5-7.8. Among children aged 7-12 months, those who were breastfed had lower prevalence of G. lamblia infection than those who had been weaned (P = 0.012.Cryptosporidium infection is common among young Tanzanian children with diarrhea, particularly those living with HIV, and infection is more frequent during the rainy season. G. lamblia is frequently implicated in asymptomatic infections, but rarely causes overt diarrheal illness, and its prevalence increases with age.

  17. Comparison between immunomagnetic separation, coupled with immunofluorescence, and the techniques of Faust et al. and of Lutz for the diagnosis of Giardia lamblia cysts in human feces

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    Souza Doris Sobral Marques

    2003-01-01

    Full Text Available In the present study, the performance of Immunomagnetic Separation technique, coupled with Immunofluorescence (IMS-IFA, was compared with the FAUST et al. and Lutz parasitological techniques for the detection of Giardia lamblia cysts in human feces. One hundred and twenty-seven samples were evaluated by the three techniques at the same time showing a rate of cyst detection of 27.5% by IMS-IFA and 15.7% by both Faust et al. and Lutz techniques. Data analysis showed a higher sensitivity of IMS-IFA for the detection of G. lamblia cysts in comparison with the techniques of FAUST et al. and Lutz. The use of this methodology as a routine procedure enables the processing of many samples simultaneously, in order to increase recovery rate of G. lamblia cysts and reduce the time of sample storage.

  18. Identification of Giardia lamblia, Entamoeba histolytica and Cryptosporidium sp. in Feces of Diarrheal Patient at Puskesmas Jatinangor, September–November 2012

    OpenAIRE

    Komathi Palani; Lia Faridah; Uun Sumardi

    2015-01-01

    Background: Diarrhea is one of the main public health problems occurring in West Java. One of the affected areas is Subdistrict Jatinangor. Inappropriate management of sanitation facilities around Jatinangor area causes contamination of water. Cikeruh River is one of the water sources in Jatinangor Area, from which people obtain water for daily activities. Water borne illness due to poor sanitation condition can lead to parasitic infection such as Giardia lamblia, Entamoeba histolytica and Cr...

  19. A systematic review of the effects of Iranian pharmaceutical plant extracts on Giardia lamblia

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    Hajar Ziaei Hezarjaribi

    2015-12-01

    Full Text Available This study aimed to provide a systematic review regarding anti-Giardia effect of different Iranian plant extracts used in vivo and in vitro on cysts and trophozoites. Many reports indicated that most of plant extracts used as anti-Giardia were obtained from Liliaceae, Apiaceae, Asteraceae, and Myrtaceae. These extracts included different fractions such as aqueous, alcoholic and chloroform extracts as well as Soxhlet extraction of juice or essence. The findings of this review showed that hydroalcoholic extract of asafoetida, Chenopodium botrys, and chloroformic extract of feverfew (Tanacetum parthenium have the maximum effect (100% efficacy on in vitro application against Giardia. However, the highest in vivo effect of 100% therapeutic significance was recorded for the extract of Allium sativum at 80 mg/mL concentration. Given the plant species richness of Iran in terms of herbal medicines with fewer side effects, it can be a good alternative to chemical drugs used to treat giardiasis.

  20. Cross-modulation of pathogen-specific pathways enhances malnutrition during enteric co-infection with Giardia lamblia and enteroaggregative Escherichia coli.

    Science.gov (United States)

    Bartelt, Luther A; Bolick, David T; Mayneris-Perxachs, Jordi; Kolling, Glynis L; Medlock, Gregory L; Zaenker, Edna I; Donowitz, Jeffery; Thomas-Beckett, Rose Viguna; Rogala, Allison; Carroll, Ian M; Singer, Steven M; Papin, Jason; Swann, Jonathan R; Guerrant, Richard L

    2017-07-01

    Diverse enteropathogen exposures associate with childhood malnutrition. To elucidate mechanistic pathways whereby enteric microbes interact during malnutrition, we used protein deficiency in mice to develop a new model of co-enteropathogen enteropathy. Focusing on common enteropathogens in malnourished children, Giardia lamblia and enteroaggregative Escherichia coli (EAEC), we provide new insights into intersecting pathogen-specific mechanisms that enhance malnutrition. We show for the first time that during protein malnutrition, the intestinal microbiota permits persistent Giardia colonization and simultaneously contributes to growth impairment. Despite signals of intestinal injury, such as IL1α, Giardia-infected mice lack pro-inflammatory intestinal responses, similar to endemic pediatric Giardia infections. Rather, Giardia perturbs microbial host co-metabolites of proteolysis during growth impairment, whereas host nicotinamide utilization adaptations that correspond with growth recovery increase. EAEC promotes intestinal inflammation and markers of myeloid cell activation. During co-infection, intestinal inflammatory signaling and cellular recruitment responses to EAEC are preserved together with a Giardia-mediated diminishment in myeloid cell activation. Conversely, EAEC extinguishes markers of host energy expenditure regulatory responses to Giardia, as host metabolic adaptations appear exhausted. Integrating immunologic and metabolic profiles during co-pathogen infection and malnutrition, we develop a working mechanistic model of how cumulative diet-induced and pathogen-triggered microbial perturbations result in an increasingly wasted host.

  1. Detection of a Giardia lamblia coproantigen by using a commercially available immunoenzymatic assay, in Belo Horizonte, Brazil Avaliação do ProSpeT Giardia ensaio em microplaca na detecção de coproantígenos de Giardia lamblia, em fezes de pacientes de Belo Horizonte, Brasil

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    Míriam Oliveira e ROCHA

    1999-05-01

    Full Text Available It is known that fecal examination to detect Giardia lamblia cysts or trophozoites produces a high percentage of false-negative results. A commercially available immunoenzymatic assay (ProSpecT Giardia Microplate Assay, Alexon, Inc., BIOBRÁS to detect G. lamblia specific coproantigen was evaluated for the first time in Brazil. A total of 90 specimens were tested. Each specimen was first tested as unpreserved stool, and then it was preserved in 10% Formalin to be tested 2 months later. The assay was able to identify all the 30 positive patients (sensitivity = 100.0% by visual or spectrophotometric examination in the unpreserved specimens and was negative in 57 of the 60 patients without G. lamblia (specificity = 95.0%. The assay identified 27 of the 30 positive patients (sensitivity = 90.0% and was negative in 59 of the 60 negatives (specificity = 98.3% in the preserved stools according to both readings. A marked difference was observed in the optical densities in both groups, preserved and unpreserved stools, when the G. lamblia-positive specimens were compared to the negative or positive for other intestinal parasites than G. lamblia. The assay seems a good alternative for giardiasis diagnosis, especially when the fecal examination was repeatedly negative and the patient presents giardiasislike symptoms.O diagnóstico da giardíase através da pesquisa de trofozoítos ou cistos do parasita nas fezes apresenta uma elevada percentagem de resultados falso-negativos. No presente trabalho foi feita, pela primeira vez no Brasil, uma avaliação do ProSpecT Giardia Ensaio em Microplaca (Alexon, Inc., BIOBRÁS, utilizando amostras fecais de pacientes de Belo Horizonte, Brasil. Um total de 90 amostras fecais foram testadas, primeiramente como fezes frescas e, então, preservadas em formalina 10%, para um novo teste 2 meses após. Com as amostras frescas, o ensaio imunoenzimático, através de leitura visual ou no espectrofotômetro, foi capaz de

  2. Click Chemistry-Facilitated Structural Diversification of Nitrothiazoles, Nitrofurans, and Nitropyrroles Enhances Antimicrobial Activity against Giardia lamblia.

    Science.gov (United States)

    Kim, Wan Jung; Korthals, Keith A; Li, Suhua; Le, Christine; Kalisiak, Jarosław; Sharpless, K Barry; Fokin, Valery V; Miyamoto, Yukiko; Eckmann, Lars

    2017-06-01

    Giardia lamblia is an important and ubiquitous cause of diarrheal disease. The primary agents in the treatment of giardiasis are nitroheterocyclic drugs, particularly the imidazoles metronidazole and tinidazole and the thiazole nitazoxanide. Although these drugs are generally effective, treatment failures occur in up to 20% of cases, and resistance has been demonstrated in vivo and in vitro Prior work had suggested that side chain modifications of the imidazole core can lead to new effective 5-nitroimidazole drugs that can combat nitro drug resistance, but the full potential of nitroheterocycles other than imidazole to yield effective new antigiardial agents has not been explored. Here, we generated derivatives of two clinically utilized nitroheterocycles, nitrothiazole and nitrofuran, as well as a third heterocycle, nitropyrrole, which is related to nitroimidazole but has not been systematically investigated as an antimicrobial drug scaffold. Click chemistry was employed to synthesize 442 novel nitroheterocyclic compounds with extensive side chain modifications. Screening of this library against representative G. lamblia strains showed a wide spectrum of in vitro activities, with many of the compounds exhibiting superior activity relative to reference drugs and several showing >100-fold increase in potency and the ability to overcome existing forms of metronidazole resistance. The majority of new compounds displayed no cytotoxicity against human cells, and several compounds were orally active against murine giardiasis in vivo These findings provide additional impetus for the systematic development of nitroheterocyclic compounds with nonimidazole cores as alternative and improved agents for the treatment of giardiasis and potentially other infectious agents. Copyright © 2017 American Society for Microbiology.

  3. Modellering van de verwijdering van Cryptosporidium parvum,Giardia lamblia en enterovirussen in spaarbekkens

    NARCIS (Netherlands)

    Ratsak CH; MGB

    1996-01-01

    De protozoa Cryptosporidium en Giardia hebben de laatste decennia in de Verenigde Staten en in Groot-Brittannie een aanzienlijk aantal grote en kleine epidemieen van maag-darminfecties via drinkwater veroorzaakt. Wiskundige modellen kunnen worden gebruikt om de verwijdering van pathogene

  4. [Experimental model of activated Lamblia (Giardia) muris infection in albino mice].

    Science.gov (United States)

    Irikov, O A; Kovalenko, F P

    2007-01-01

    Experimental L. muris infection was reproduced in 100% of the intact albino mice intragastrically given levomycin in an average total dose of 15.88-34.84 or 0.88-1.02 g/kg for 18-34 days. With levomycin administration, the intensity of giardiasis was 1121.6-8540.1 (mean 4830.9) thousand L. muris trophozoites per animal. The total number of trophozoites per animal decreased to 302.2-3481.4 (mean 1546.4) thousand and 28.1-324.0 (mean 109.4) thousand specimens 5-8 and 11-13 days after discontinuation of the antibiotic, respectively. The maximum number of L. muris trophozoites was observed in the proximal and middle portions of the murine small intestine during and after the administration oflevomycin. The highest isolation of cysts was seen 12-14 days after the initiation of administration of the antibiotic. Following 8-10 days of terminations of a course of levomycin therapy the native smear of animal feces showed no Lamblia cysts. In mice with activated infection, the isolation rate of Lamblia cysts was directly related to the intensity of intestinal infection with trophozoites of the parasite.

  5. Synthesis and Electrochemistry of 2-Ethenyl and 2-Ethanyl Derivatives of 5-Nitroimidazole and Antimicrobial Activity against Giardia lamblia

    Science.gov (United States)

    Valdez, Carlos A.; Tripp, Jonathan C.; Miyamoto, Yukiko; Kalisiak, Jaroslaw; Hruz, Petr; Andersen, Yolanda S.; Brown, Sabrina E.; Kangas, Karina; Arzu, Leo V.; Davids, Barbara J.; Gillin, Frances D.; Upcroft, Jacqueline A.; Upcroft, Peter; Fokin, Valery V.; Smith, Diane K.; Sharpless, K. Barry; Eckmann, Lars

    2009-01-01

    Infections with the diarrheagenic pathogen, Giardia lamblia, are commonly treated with the 5-nitroimidazole (5-NI) metronidazole (Mz), and yet treatment failures and Mz resistance occur. Using a panel of new 2-ethenyl and 2-ethanyl 5-NI derivatives, we found that compounds with a saturated bridge between the 5-NI core and a pendant ring system exhibited only modestly increased antigiardial activity and could not overcome Mz resistance. By contrast, olefins with a conjugated bridge connecting the core and a substituted phenyl or heterocyclic ring showed greatly increased antigiardial activity without toxicity, and several overcame Mz resistance and were more effective than Mz in a murine giardiasis model. Determination of the half-wave potential of the initial one-electron transfer by cyclic voltammetry revealed that easier redox activation correlated with greater antigiardial activity and capacity to overcome Mz resistance. These studies show the potential of combining systematic synthetic approaches with biological and electrochemical evaluations in developing improved 5-NI drugs. PMID:19480409

  6. Rapid Detection and Enumeration of Giardia lamblia Cysts in Water Samples by Immunomagnetic Separation and Flow Cytometric Analysis ▿ †

    Science.gov (United States)

    Keserue, Hans-Anton; Füchslin, Hans Peter; Egli, Thomas

    2011-01-01

    Giardia lamblia is an important waterborne pathogen and is among the most common intestinal parasites of humans worldwide. Its fecal-oral transmission leads to the presence of cysts of this pathogen in the environment, and so far, quantitative rapid screening methods are not available for various matrices, such as surface waters, wastewater, or food. Thus, it is necessary to establish methods that enable reliable rapid detection of a single cyst in 10 to 100 liters of drinking water. Conventional detection relies on cyst concentration, isolation, and confirmation by immunofluorescence microscopy (IFM), resulting in low recoveries and high detection limits. Many different immunomagnetic separation (IMS) procedures have been developed for separation and cyst purification, so far with variable but high losses of cysts. A method was developed that requires less than 100 min and consists of filtration, resuspension, IMS, and flow cytometric (FCM) detection. MACS MicroBeads were used for IMS, and a reliable flow cytometric detection approach was established employing 3 different parameters for discrimination from background signals, i.e., green and red fluorescence (resulting from the distinct pattern emitted by the fluorescein dye) and sideward scatter for size discrimination. With spiked samples, recoveries exceeding 90% were obtained, and false-positive results were never encountered for negative samples. Additionally, the method was applicable to naturally occurring cysts in wastewater and has the potential to be automated. PMID:21685159

  7. Comparative analysis of the 5S rRNA and its associated proteins reveals unique primitive rather than parasitic features in Giardia lamblia.

    Science.gov (United States)

    Feng, Jin-Mei; Sun, Jun; Xin, De-Dong; Wen, Jian-Fan

    2012-01-01

    5S rRNA is a highly conserved ribosomal component. Eukaryotic 5S rRNA and its associated proteins (5S rRNA system) have become very well understood. Giardia lamblia was thought by some researchers to be the most primitive extant eukaryote while others considered it a highly evolved parasite. Previous reports have indicated that some aspects of its 5S rRNA system are simpler than that of common eukaryotes. We here explore whether this is true to its entire system, and whether this simplicity is a primitive or parasitic feature. By collecting and confirming pre-existing data and identifying new data, we obtained almost complete datasets of the system of three isolates of G. lamblia, two other parasitic excavates (Trichomonas vaginalis, Trypanosoma cruzi), and one free-living one (Naegleria gruberi). After comprehensively comparing each aspect of the system among these excavates and also with those of archaea and common eukaryotes, we found all the three Giardia isolates to harbor a same simplified 5S rRNA system, which is not only much simpler than that of common eukaryotes but also the simplest one among those of these excavates, and is surprisingly very similar to that of archaea; we also found among these excavates the system in parasitic species is not necessarily simpler than that in free-living species, conversely, the system of free-living species is even simpler in some respects than those of parasitic ones. The simplicity of Giardia 5S rRNA system should be considered a primitive rather than parasitically-degenerated feature. Therefore, Giardia 5S rRNA system might be a primitive system that is intermediate between that of archaea and the common eukaryotic model system, and it may reflect the evolutionary history of the eukaryotic 5S rRNA system from the archaeal form. Our results also imply G. lamblia might be a primitive eukaryote with secondary parasitically-degenerated features.

  8. The role of free-ranging, captive, and domestic birds of Western Poland in environmental contamination with Cryptosporidium parvum oocysts and Giardia lamblia cysts.

    Science.gov (United States)

    Majewska, Anna C; Graczyk, Thaddeus K; Słodkowicz-Kowalska, Anna; Tamang, Leena; Jedrzejewski, Szymon; Zduniak, Piotr; Solarczyk, Piotr; Nowosad, Andrzej; Nowosad, Piotr

    2009-04-01

    As Cryptosporidium parvum and Giardia lamblia can be disseminated in the environment by avian hosts, a total of 499 fecal dropping from 308 free-ranging, 90 captive, and 101 domestic birds were tested by conventional, immunological, and molecular techniques for these human enteropathogens. Twenty-six (5.2%) tested positive for G. lamblia cysts and 19 (3.8%) for C. parvum oocysts. A bird total of 23 (7.5%) free-ranging, two (2.2%) captive, and one (0.1%) domestic tested positive for cysts, whereas 18 (5.8%) free-ranging, one (1.1%) captive, and zero livestock birds tested positive for oocysts. G. lamblia cysts and C. parvum oocysts were found significantly more frequently in fecal droppings of free-ranging aquatic birds than in birds not normally associated with water. No specimen tested positive for both pathogens simultaneously. Aquatic birds represent an important epidemiologic link in water-associated transmission cycles of Cryptosporidium and Giardia and play a significant role in environmental contamination of aquatic habitats with these anthropozoonotic pathogens.

  9. Multiplex PCR detection of Cryptosporidium sp, Giardia lamblia and Entamoeba histolytica directly from dried stool samples from Guinea-Bissauan children with diarrhoea.

    Science.gov (United States)

    Mero, Sointu; Kirveskari, Juha; Antikainen, Jenni; Ursing, Johan; Rombo, Lars; Kofoed, Poul-Erik; Kantele, Anu

    2017-09-01

    In developing countries, diarrhoea is the most common cause of death for children under five years of age, with Giardia lamblia, Cryptosporidium and Entamoeba histolytica as the most frequent pathogenic parasites. Traditional microscopy for stool parasites has poor sensitivity and specificity, while new molecular methods may provide more accurate diagnostics. In poor regions with sample storage hampered by uncertain electricity supply, research would benefit from a method capable of analysing dried stools. A real-time multiplex PCR method with internal inhibition control was developed for detecting Giardia lamblia, Cryptosporidium hominis/parvum and Entamoeba histolytica directly from stool specimens. Applicability to dried samples was checked by comparing with fresh ones in a small test material. Finally, the assay was applied to dried specimens collected from Guinea-Bissauan children with diarrhoea. The PCR's analytical sensitivity limit was 0.1 ng/ml for G. lamblia DNA, 0.01 ng/ml for E. histolytica DNA and 0.1 ng/ml for Cryptosporidium sp. In the test material, the assay performed similarly with fresh and dried stools. Of the 52 Guinea-Bissauan samples, local microscopy revealed a parasite in 15%, while PCR detected 62% positive for at least one parasite: 44% of the dried samples had Giardia, 23% Cryptosporidium and 0% E. histolytica. Our new multiplex real-time PCR for protozoa presents a sensitive method applicable to dried samples. As proof of concept, it worked well on stools collected from Guinea-Bissauan children with diarrhoea. It provides an epidemiological tool for analysing dried specimens from regions poor in resources.

  10. Ciclo zoonótico rural de Giardia lamblia en dos campos lecheros de General Mansilla, Buenos Aires

    OpenAIRE

    Molina, Nora Beatriz; Basualdo Farjat, Juan Ángel; Minvielle, Marta Cecilia

    2010-01-01

    Giardia lamblia es el protozoo productor de diarrea diagnosticado con más frecuencia en todo el mundo. La giardiosis es una infección cosmopolita de tipo zoonótico cuya prevalencia varía de 2% en países industrializados al 70% en países en desarrollo (Eligio-García y col. 2008). En Argentina, esta parasitosis muestra una prevalencia variable de 6% a 36% dependiendo de las condiciones sanitarias de cada región y de los hábitos de higiene personal (Minvielle y col. 2004; Basualdo y col. 2007; S...

  11. Comparação de quatro métodos laboratoriais para o diagnóstico da Giardia lamblia em fezes de crianças da região de Araraquara-SP

    OpenAIRE

    Garcia, José Gustavo Donato [UNESP

    2005-01-01

    O protozoário Giardia lamblia foi escolhido como tema de estudo, por ser um enteroparasita de prevalência significativa no mundo inteiro. Os objetivos desta pesquisa foram estudar a reprodutibilidade diagnóstica dos métodos Direto, Faust e cols., COPROTEST e Hematoxilina Férrica, bem como descrever a presença da Giardia lamblia, segundo a associação com algumas características da população de estudo como: grupo etário, gênero e distribuição dos casos segundo a variação sazonal nos meses em qu...

  12. Stem-Loop RT-qPCR as an Efficient Tool for the Detection and Quantification of Small RNAs in Giardia lamblia

    Science.gov (United States)

    Marcial-Quino, Jaime; Gómez-Manzo, Saúl; Fierro, Francisco; Vanoye-Carlo, America; Rufino-González, Yadira; Sierra-Palacios, Edgar; Castillo-Villanueva, Adriana; Castillo-Rodríguez, Rosa Angélica; Rodríguez-Bustamante, Eduardo; Arreguin-Espinosa, Roberto; Reyes-Vivas, Horacio

    2016-01-01

    Stem-loop quantitative reverse transcription PCR (RT-qPCR) is a molecular technique used for identification and quantification of individual small RNAs in cells. In this work, we used a Universal ProbeLibrary (UPL)-based design to detect—in a rapid, sensitive, specific, and reproducible way—the small nucleolar RNA (snoRNA) GlsR17 and its derived miRNA (miR2) of Giardia lamblia using a stem-loop RT-qPCR approach. Both small RNAs could be isolated from both total RNA and small RNA samples. Identification of the two small RNAs was carried out by sequencing the PCR-amplified small RNA products upon ligation into the pJET1.2/blunt vector. GlsR17 is constitutively expressed during the 72 h cultures of trophozoites, while the mature miR2 is present in 2-fold higher abundance during the first 48 h than at 72 h. Because it has been suggested that miRNAs in G. lamblia have an important role in the regulation of gene expression, the use of the stem-loop RT-qPCR method could be valuable for the study of miRNAs of G. lamblia. This methodology will be a powerful tool for studying gene regulation in G. lamblia, and will help to better understand the features and functions of these regulatory molecules and how they work within the RNA interference (RNAi) pathway in G. lamblia. PMID:27999395

  13. Stem-Loop RT-qPCR as an Efficient Tool for the Detection and Quantification of Small RNAs in Giardia lamblia

    Directory of Open Access Journals (Sweden)

    Jaime Marcial-Quino

    2016-12-01

    Full Text Available Stem-loop quantitative reverse transcription PCR (RT-qPCR is a molecular technique used for identification and quantification of individual small RNAs in cells. In this work, we used a Universal ProbeLibrary (UPL-based design to detect—in a rapid, sensitive, specific, and reproducible way—the small nucleolar RNA (snoRNA GlsR17 and its derived miRNA (miR2 of Giardia lamblia using a stem-loop RT-qPCR approach. Both small RNAs could be isolated from both total RNA and small RNA samples. Identification of the two small RNAs was carried out by sequencing the PCR-amplified small RNA products upon ligation into the pJET1.2/blunt vector. GlsR17 is constitutively expressed during the 72 h cultures of trophozoites, while the mature miR2 is present in 2-fold higher abundance during the first 48 h than at 72 h. Because it has been suggested that miRNAs in G. lamblia have an important role in the regulation of gene expression, the use of the stem-loop RT-qPCR method could be valuable for the study of miRNAs of G. lamblia. This methodology will be a powerful tool for studying gene regulation in G. lamblia, and will help to better understand the features and functions of these regulatory molecules and how they work within the RNA interference (RNAi pathway in G. lamblia.

  14. In vitro anti-Giardia lamblia activity of 2-aryl-3-hydroxymethyl imidazo[1,2-a]pyridines and -pyrimidines, individually and in combination with albendazole.

    Science.gov (United States)

    Velázquez-Olvera, Stephanía; Salgado-Zamora, Héctor; Jiménez-Cardoso, Enedina; Campos-Aldrete, Maria-Elena; Pérez-González, Cuauhtémoc; Ben Hadda, Taibi

    2016-03-01

    Giardiasis is a major diarrheal disease found throughout the world, the causative agent being the flagellate protozoan Giardia intestinalis. Infection is more common in children than in adults. The appearance of drug resistance has complicated the treatment of several parasitic diseases, including giardiasis. Thus, the aim of this investigation was to make an in vitro evaluation of the antigiardia response of synthetic derivatives 2-aryl-3-hydroxymethylimidazo[1,2-a]pyridines 1 and -pyrimidines 2 against trophozoites of Giardia lamblia WB, in comparison with the reference drug, albendazole. Additionally, the synergistic action of albendazole in combination with each of the most active 2-aryl-3-hydroxymethyl imidazo[1,2-a]pyridines and pyrimidines was also assessed. Based on the IC50 values obtained, the best anti-Giardia activity was provided by the 3-hydroxymethyl-4-fluorophenylimidazo[1,2-a]pyrimidine derivative 2c and the corresponding imidazo[1,2-a]pyrimidine with the p-tolyl substituent 2d, followed by 2a and 2b. These four compounds showed effectiveness at a concentration similar to that of albendazole. Regarding synergism, the IC50 of the combination of albendazole with 2a, 2b or 2c gave the best anti-Giardia action, showing greater efficacy than albendazole alone. Hence, G. lamblia WB showed high susceptibility to some 2-aryl-3-hydroxymethyl imidazo[1,2-a] pyrimidines, which acted synergistically when used in combination with albendazole. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Identification of Giardia lamblia, Entamoeba histolytica and Cryptosporidium sp. in Feces of Diarrheal Patient at Puskesmas Jatinangor, September–November 2012

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    Komathi Palani

    2015-06-01

    Full Text Available Background: Diarrhea is one of the main public health problems occurring in West Java. One of the affected areas is Subdistrict Jatinangor. Inappropriate management of sanitation facilities around Jatinangor area causes contamination of water. Cikeruh River is one of the water sources in Jatinangor Area, from which people obtain water for daily activities. Water borne illness due to poor sanitation condition can lead to parasitic infection such as Giardia lamblia, Entamoeba histolytica and Cryptosporidium parvum which can cause a prolonged diarrhea. There has not been any study done regarding the presence of parasitical infection causing diarrhea around Jatinangor. Methods: In order to identify the parasitic infection, a descriptive study was carried out on 16 fecal samples collected from diarrheal patient who visited Puskesmas Jatinangor from September–November 2012. The parasites were checked by using wet mount method Results: The parasites found were Entamoeba histolytica, Cryptosporidium parvum, but none of Giardia lamblia. There were also other findings such as Iodamoeba butschlii and Entamoeba coli. Conclusion: Positive findings of Entamoeba histolytica and Cryptosporidium parvum in diarrhea patients is most probably due to contaminated water and food. Measures need to be done to improve sanitary condition in Cikeruh River to prevent diarrhea.

  16. Molecular characterization of Giardia lamblia in children less than 5 years of age with diarrhoea attending the Bengo General Hospital, Angola

    Science.gov (United States)

    Gasparinho, Carolina; Ferreira, Filipa S; Mayer, António Carlos; Mirante, Maria Clara; Vaz Nery, Susana; Santos-Reis, Ana; Portugal-Calisto, Daniela; Brito, Miguel

    2017-01-01

    Abstract Background Giardia lamblia is a pathogenic intestinal protozoan with high prevalence in developing countries, especially among children. Molecular characterization has revealed the existence of eight assemblages, with A and B being more commonly described in human infections. Despite its importance, to our knowledge this is the first published molecular analysis of G. lamblia assemblages in Angola. Methods The present study aimed to identify the assemblages of G. lamblia in children with acute diarrhoea presenting at the Bengo General Hospital, Angola. A stool sample was collected and microscopy and immunochromatographic tests were used. DNA was extracted and assemblage determination was performed through amplification of the gene fragment ssu-rRNA (175 bp) and β-giardin (511 bp) through polymerase chain reaction and DNA sequencing. Results Of the 16 stool samples screened, 12 were successfully sequenced. Eleven isolates were assigned to assemblage B and one to assemblage A. Subassemblage determination was not possible for assemblage B, while the single isolate assigned to assemblage A was identified as belonging to subassemblage A3. Conclusion This study provides information about G. lamblia assemblages in Bengo Province, Angola and may contribute as a first step in understanding the molecular epidemiology of this protozoan in the country. GenBank accession numbers for the ssur-RNA gene: MF479750, MF479751, MF479752, MF479753, MF479754, MF479755, MF479756, MF479757, MF479758, MF479759, MF479760, MF479761. GenBank accession numbers for the β-giardin gene: MF565378, MF565379, MF565380, MF565381. PMID:29438541

  17. Identification and determination of the viability of Giardia lamblia cysts and Cryptosporidium parvum and Cryptosporidium hominis oocysts in human fecal and water supply samples by fluorescent in situ hybridization (FISH) and monoclonal antibodies.

    Science.gov (United States)

    Lemos, Vanessa; Graczyk, Thaddeus K; Alves, Margarida; Lobo, Maria Luísa; Sousa, Maria C; Antunes, Francisco; Matos, Olga

    2005-12-01

    In the present study, fluorescent in situ hybridization (FISH) and monoclonal antibodies (MAbs) were evaluated for species-specific detection and viability determination of Giardia lamblia, Cryptosporidium parvum, and Cryptosporidium hominis in human fecal and water supply samples. A total of 50 fecal human samples positive for G. lamblia cysts, 38 positive for C. parvum, and 23 positive for C. hominis were studied. Also, 18 water supply samples positive for Giardia spp. and Cryptosporidium spp. by the United States Environmental Protection Agency (USEPA) Method 1623 were studied by FISH and fluorescein isothiocyanate (FITC)-conjugated MAbs. Eighteen percent of the fecal samples parasitologically positive for G. lamblia presented viable and nonviable cysts, and 5% of those positive for Cryptosporidium spp. presented viable and nonviable oocysts. Of the 18 water supply samples analyzed, 6 (33%) presented Giardia spp. viable and nonviable cysts and 2 (11%) presented viable and nonviable Cryptosporidium spp. oocysts. G. lamblia identification was confirmed by polymerase chain reaction (PCR) and sequencing of the beta-giardin gene in the fecal and water samples found positive by FISH and FITC-conjugated MAbs. C. parvum and Cryptosporidium muris were identified, by PCR and sequencing of the small subunit of ribosomal RNA gene, in seven and one water samples, respectively. Our results confirm that this technique enables simultaneous visualization, species-specific identification, and viability determination of the organisms present in human fecal and water supply samples.

  18. Studies of Giardia lamblia

    Science.gov (United States)

    1994-10-05

    isoenzyme analysis of 19 axenic strains isolated from symptomatic and asymptomatic patients in Mexico . Trans. R. Soc. Trop. Med. Hyg. 83 : 644-646...antibody studies with agents of Varicella and Herpes Zoster propagated in vitro. Proe. Soc. Exptl. BioI. Med . 86 :7 89-794. Woo, P. and G.S. Panayi

  19. Host-Parasite Interactions in Individuals with Type 1 and 2 Diabetes Result in Higher Frequency of Ascaris lumbricoides and Giardia lamblia in Type 2 Diabetic Individuals

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    Eleuza Rodrigues Machado

    2018-01-01

    Full Text Available Host-parasite interactions in diabetic patients might influence diabetes complications and intestinal parasitosis. The aim was to investigate the occurrence of enteroparasites in individuals with diabetes types 1 and 2. A descriptive study was designed to estimate frequencies of parasites and to compare them in individuals with diabetes types 1 and 2 from two Health Centers and one hospital in the Federal District of Brazil. Patients were allocated to the study by convenience. Three fecal samples of 156 diabetic individuals (120 type 1 and 36 type 2 were analyzed using two parasitological methods. Enteroparasites or commensals frequency in diabetics was 64%. Diabetics infected with up to six species of intestinal parasites or commensals were found. Frequencies of Ascaris lumbricoides and Giardia lamblia were higher in individuals with type 2 diabetes. The lower frequency of A. lumbricoides found in type 1 diabetes may be related to a strong Th2 response to parasites. Autoimmune response developed in type 1 diabetic individuals characterized by the production of Th1 cytokines could explain low frequency of G. lamblia. High frequency of parasites found in type 2 diabetes emphasizes the importance of periodic parasitological examinations in these individuals.

  20. Developmental changes in the adhesive disk during Giardia differentiation.

    Science.gov (United States)

    Palm, Daniel; Weiland, Malin; McArthur, Andrew G; Winiecka-Krusnell, Jadwiga; Cipriano, Michael J; Birkeland, Shanda R; Pacocha, Sarah E; Davids, Barbara; Gillin, Frances; Linder, Ewert; Svärd, Staffan

    2005-06-01

    Giardia lamblia is a protozoan parasite infecting the upper mammalian small intestine. Infection relies upon the ability of the parasite to attach to the intestine via a unique cytoskeletal organelle, the ventral disk. We determined the composition and structure of the disk throughout the life cycle of the parasite and identified a new disk protein, SALP-1. SALP-1 is an immunodominant protein related to striated fiber-assemblin (SFA). The disk is disassembled during encystation and stored as four fragments in the immobile cyst. Serial Analysis of Gene Expression (SAGE) showed that the mRNA levels of the disk proteins decreased in encystation but two-dimensional protein gels showed that the protein levels were more constant. The parasite emerges without a functional disk but the four disk fragments are quickly reassembled into two new disks on the dividing, early excysting form. Thus, disk proteins are stored within the cyst, ready to be used in the rapid steps of excystation.

  1. The proteasome of the differently-diverged eukaryote Giardia lamblia and its role in remodeling of the microtubule-based cytoskeleton.

    Science.gov (United States)

    Ray, Atrayee; Sarkar, Srimonti

    2017-08-01

    Giardia lamblia is the causative agent of the diarrheal disease giardiasis, against which only a limited number of drugs are currently available. Increasing reports of resistance to these drugs makes it necessary to identify new cellular targets for designing the next generation of anti-giardial drugs. Towards this goal, therapeutic agents that target the parasitic cellular machinery involved in the functioning of the unique microtubule-based cytoskeleton of the Giardia trophozoites are likely to be effective as microtubule function is not only important for the survival of trophozoites within the host, but also their extensive remodeling is necessary during the transition from trophozoites to cysts. Thus, drugs that affect microtubule remodeling have the potential to not only kill the disease-causing trophozoites, but also inhibit transmission of cysts in the community. Recent studies in other model organisms have indicated that the proteasome plays an integral role in the formation and remodeling of the microtubule-based cytoskeleton. This review draws attention to the various processes by which the giardial proteasome may impact the functioning of its microtubule cytoskeleton and highlights the possible differences of the parasitic proteasome and some of other cellular machinery involved in microtubule remodeling, compared to that of the higher eukaryotic host.

  2. UTILIDAD TERAPÉUTICA DEL ALBENDAZOL EN EL TRATAMIENTO DE NIÑOS INFECTADOS CON Giardia lamblia I THERAPEUTIC USEFULNESS OF ALBENDAZOLE IN THE TREATMENT OF INFECTED CHILDREN WITH Giardia lambli

    Directory of Open Access Journals (Sweden)

    MAYRA RISCO

    2018-05-01

    Full Text Available A study was conducted with 22 parasitized school children with Giardia lamblia to verify the therapeutic usefulness of albendazole (400 mg single dose for 5 days. After treating the children post-treatment controls were made at 7, 15 and 21 days by clinical examination and parasitological methods (direct examination, Kato and spontaneous sedimentation. The overall rate of parasitological cure was 44.4% (8/18 consisting of 8 children in whom the parasite was eradicated after treatment. This analysis excluded 4 of the treated children because they had missed one or more post-treatment controls. Of these 18 children, 72.2% (13 children had clinical manifestations suggestive of infection with G. lamblia before receiving the drug; after completion of treatment only two school children (11.1% had clinical manifestations. However, the difference was not statistically significant (X 2 = 0.5098 d.f. = 1. Two (11.1% of the children who received albendazole had adverse effects (bitter taste and abdominal pain. In conclusion, the study group and due to its low parasitological cure rate, albendazole does not seem to be a drug of choice and use should be reserved in proven cases of resistance to metronidazole or when there is intolerance to this drug.

  3. Giardia y giardiasis Giardia and giardiasis

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    Hugo D. Luján

    2006-02-01

    Full Text Available Giardia lamblia es un protozoario parásito que habita el intestino delgado de los seres humanos y de muchos otros vertebrados y es una de las más comunes causas de diarrea en todo el mundo. Durante su ciclo de vida Giardia sufre significativos cambios bioquímicos y morfológicos que le permiten sobrevivir en ambientes y condiciones que de otro modo lo destruirían. Para sobrevivir fuera del intestino del hospedador, los trofozoítos de Giardia se diferencian a quistes, los que se caracterizan por poseer una rígida pared glicoproteica externa que les permiten sobrevivir inclusive frente a la acción de los desinfectantes más comunes. Otro de los mecanismos de adaptación de este parásito es la variación de los antígenos de superficie que le permite a los trofozoítos evadir la respuesta inmune del huésped y generar infecciones tanto agudas como crónicas o recurrentes en individuos infectados. Durante los últimos años se han producido importantes avances en el conocimiento de las bases moleculares de los procesos de enquistamiento y variación antigénica en Giardia que pronostican el pronto hallazgo de nuevos agentes quimioterapéuticos y/o inmunoprofilácticos contra este importante parásito intestinal.Giardia lamblia is a protozoan parasite that inhabits the upper small intestine of humans and several other vertebrates and one of the most frequent cause of intestinal disease worldwide. During its life cycle, G. lamblia undergoes significant biochemical and morphological changes that allow the parasite to survive under hostile environmental conditions. To survive outside the host’s intestine, Giardia differentiates into resistant cysts, which are characterized by a rigid extracellular cyst wall that protect the parasite even to the action of the most common chemical disinfectants. Another adaptive mechanism of Giardia is the switching of its surface antigens, a mechanism that allows the trophozoites to evade the host’s immune

  4. Comparação de quatro métodos laboratoriais para diagnóstico da Giardia lamblia em fezes de crianças residentes em Belém, Pará

    OpenAIRE

    Machado,Ricardo Luiz Dantas; Figueredo,Maria Cristina; Frade,Amanda Farage; Kudó,Mônica Eriko; Silva Filho,Manoel Gomes; Póvoa,Marinete Marins

    2001-01-01

    Relatamos a comparação de quatro metodologias para o diagnóstico da Giardia lamblia em material fecal de crianças, Belém/PA. A Hematoxilina Férrica e o método direto apresentaram menor positividade, enquanto que o Método de Faust continua uma boa escolha para o diagnóstico e o Ensaio imunoenzimático melhora a qualidade da detecção deste parasito.

  5. Enquistación in vitro de Giardia lamblia: análisis por electroforesis bidimensional de proteínas expresadas diferencialmente.

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    Paula C. Hernández

    2002-09-01

    Full Text Available La reconstrucción in vitro del ciclo de vida de Giardia lamblia es un excelente instrumento para el estudio de la biología molecular del parásito. El presente trabajo pretende contribuir al desarrollo de algunas técnicas por las cuales se puede definir mejor un modelo de diferenciación celular del parásito. El estudio presenta un protocolo de enquistación in vitro y establece un método para el aislamiento y la purificación de los quistes producidos, cuyas características morfológicas, por microscopía de luz, coinciden con las de los quistes obtenidos in vivo. Se estudió el mapa de las proteínas de G. lamblia por medio de electroforesis bidimensional de alta resolución y de electroforesis en una dimensión. Estos estudios mostraron que la mayoría de las proteínas del parásito son de carácter ácido. Se amplió, con base en ese resultado, la resolución de la región ácida por medio de un isoelectroenfoque de pH 4-7 en la primera dimensión. Se encontraron diferencias en la expresión de las proteínas durante el proceso de enquistación. Se obtuvieron, además, imágenes por microscopía de luz y electrónica de transmisión que permitieron observar morfológica y ultraestructuralmente las células producidas durante el proceso de la enquistación.

  6. Mecanismos específicos de patogenicidade de protozoários de mucosa: Entamoeba histolytica, Giardia lamblia e Trichomonas vaginalis

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    Patrícia de Brum Vieira

    2012-04-01

    Full Text Available Entamoeba histolytica e Giardia lamblia são protozoários que podem parasitar a mucosa intestinal, causando principalmente diarreia. Trichomonas vaginalis coloniza a mucosa vaginal causando tricomonose, a doença sexualmente transmissível não viral mais comum no mundo. Embora coletivamente estes parasitos infectem mais de um bilhão de pessoas a cada ano, seus mecanismos de patogenicidade ainda não estão totalmente esclarecidos. Assim, esta revisão reúne os principais mecanismos envolvidos na patogenicidade destes protozoários, bem como os fatores do microambiente que podem interferir no sucesso da colonização. A patogênese da E. histolytica envolve adesão, lise, fagocitose de células epiteliais e bactérias, invasão tecidual por ação de enzimas e evasão da resposta imune do hospedeiro. A lectina Gal/GalNAc, os amebaporos e as cisteína proteases são as principais moléculas envolvidas nesses processos. O estabelecimento da giardiose depende de diversos mecanismos patogênicos e de virulência desenvolvidos pela G. lamblia, tais como as moléculas envolvidas na adesão, encistamento e variação antigênica. Para o sucesso da colonização da mucosa vaginal, o T. vaginalis expressa moléculas como as adesinas de superfície, lipofosfoglicanos e galectina, envolvidas na adesão às células epiteliais vaginais e alteração da expressão gênica, tanto do parasito como do hospedeiro.

  7. Identification of Giardia lamblia and the human infectious-species of Cryptosporidium in drinking water resources in Western Saudi Arabia by nested-PCR assays.

    Science.gov (United States)

    Hawash, Y; Ghonaim, M; Hussein, Y; Alhazmi, A; Alturkistani, A

    2015-06-01

    The presence of Cryptosporidium and/or Giardia in drinking water represents a major public health problem. This study was the first report concerned with the occurrence of these protozoa in drinking water in Saudi Arabia. The study was undertaken in Al-Taif, a high altitude region, Western Saudi Arabia. Eight underground wells water, six desalinated water and five domestic brands of bottled water samples, 10 liter each, were monthly collected between May 2013 and April 2014. All samples (n = 228), were processed using an automated wash/elution station (IDEXX Laboratories, Inc.). Genomic DNA was directly isolated and purified from samples concentrates with QIAamp® Stool Mini Kit (Qiagen). The target protozoan DNA sequences were amplified using two previously published nested-PCR protocols. Of all the analyzed water, 31 samples (≈14%) were found contaminated with the target protozoa. Giardia lamblia was detected in ≈10% (7/72) of desalinated water and in ≈9% (9/96) of wells water. On the other hand, Cryptosporidium was identified in ≈8% (8/72) of desalinated water and in ≈7% (7/96) of wells water. All bottled water samples (n = 60) were (oo)cysts-free. Protozoan (oo)cysts were more frequently identified in water samples collected in the spring than in other seasons. The methodology established in our study proved sensitive, cost-effective and is amenable for future automation or semi-automation. For better understanding of the current situation that represent an important health threat to the local inhabitants, further studies concerned with (oo)cyst viability, infectivity, concentration and genotype identification are recommended.

  8. Antiparasitic activity of diallyl trisulfide (Dasuansu) on human and animal pathogenic protozoa (Trypanosoma sp., Entamoeba histolytica and Giardia lamblia) in vitro.

    Science.gov (United States)

    Lun, Z R; Burri, C; Menzinger, M; Kaminsky, R

    1994-03-01

    Garlic (Allium sativum L.) and one of its major components, allicin, have been known to have antibacterial and antifungal activity for a long time. Diallyl trisulfide is a chemically stable final transformation product of allicin which was synthesized in 1981 in China and used for treatment of bacterial, fungal and parasitic infections in man. The activity of diallyl trisulfide was investigated in several important protozoan parasites in vitro. The IC50 (concentration which inhibits metabolism or growth of parasites by 50%) for Trypanosoma brucei brucei, T.b. rhodesiense, T.b. gambiense, T. evansi, T. congolense and T. equiperdum was in the range of 0.8-5.5 micrograms/ml. IC50 values were 59 micrograms/ml for Entamoeba histolytica and 14 micrograms/ml for Giardia lamblia. The cytotoxicity of the compound was evaluated on two fibroblast cell lines (MASEF, Mastomys natalensis embryo fibroblast and HEFL-12, human embryo fibroblast) in vitro. The maximum tolerated concentration for both cell lines was 25 micrograms/ml. The results indicate that the compound has potential to be used for treatment of several human and animal parasitic diseases.

  9. Structure-activity studies of dicationically substituted bis-benzimidazoles against Giardia lamblia: correlation of antigiardial activity with DNA binding affinity and giardial topoisomerase II inhibition.

    Science.gov (United States)

    Bell, C A; Dykstra, C C; Naiman, N A; Cory, M; Fairley, T A; Tidwell, R R

    1993-01-01

    Nine dicationically substituted bis-benzimidazoles were examined for their in vitro activities against Giardia lamblia WB (ATCC 30957). The potential mechanisms of action of these compounds were evaluated by investigating the relationship among in vitro antigiardial activity and the affinity of the molecules for DNA and their ability to inhibit the activity of giardial topoisomerase II. Each compound demonstrated antigiardial activity, as measured by assessing the incorporation of [methyl-3H]thymidine by giardial trophozoites exposed to the test agents. Three compounds exhibited excellent in vitro antigiardial activities, with 50% inhibitory concentrations which compared very favorably with those of two currently used drugs, quinacrine HCl and metronidazole. Putative mechanisms of action for these compounds were suggested by the strong correlation observed among in vitro antigiardial activity and the affinity of the molecules for natural and synthetic DNA and their ability to inhibit the relaxation activity of giardial topoisomerase II. A strong correlation between the DNA binding affinity of these compounds and their inhibition of giardial topoisomerase II activity was also observed. Images PMID:8109934

  10. Comparison of the Triage Micro Parasite Panel and Microscopy for the Detection of Entamoeba histolytica/Entamoeba dispar, Giardia lamblia, and Cryptosporidium parvum in Stool Samples Collected in Kenya

    Directory of Open Access Journals (Sweden)

    Brett Swierczewski

    2012-01-01

    Full Text Available Entamoeba histolytica, Giardia lamblia, and Cryptosporidium parvum are three of the most important parasitic causes of acute diarrhea worldwide. Laboratory diagnosis of these parasites is usually done by ova and parasite examination (O&P examination via microscopy. The sensitivity and specificity of O&P examination varies among laboratories and can be labor intensive and time consuming. The Triage Micro Parasite Panel (BioSite, San Diego, California is an enzyme immunoassay kit that can detect E. histolytica/E. dispar, G. lamblia, and C. parvum simultaneously using fresh or frozen stool. The present study evaluated the Triage Micro Parasite Panel in detecting E. histolytica/E. dispar, G. lamblia, and C. parvum compared to O&P examination in 266 stool samples collected at medical facilities in Kenya. The sensitivity and specificity results for the Triage Micro Parasite Panel were: for E. histolytica/E. dispar: 100%, 100%, G. lamblia: 100%, 100% and C. parvum: 73%, 100%. There was no evidence of cross reactivity using the kit with other parasites identified in the stool specimens. These results indicate that the Triage Micro Parasite Panel is a highly sensitive kit that can be used for screening purposes in large scale studies or outbreak investigations or as a possible alternative to O&P examination.

  11. An Interactome-Centered Protein Discovery Approach Reveals Novel Components Involved in Mitosome Function and Homeostasis in Giardia lamblia.

    Directory of Open Access Journals (Sweden)

    Samuel Rout

    2016-12-01

    Full Text Available Protozoan parasites of the genus Giardia are highly prevalent globally, and infect a wide range of vertebrate hosts including humans, with proliferation and pathology restricted to the small intestine. This narrow ecological specialization entailed extensive structural and functional adaptations during host-parasite co-evolution. An example is the streamlined mitosomal proteome with iron-sulphur protein maturation as the only biochemical pathway clearly associated with this organelle. Here, we applied techniques in microscopy and protein biochemistry to investigate the mitosomal membrane proteome in association to mitosome homeostasis. Live cell imaging revealed a highly immobilized array of 30-40 physically distinct mitosome organelles in trophozoites. We provide direct evidence for the single giardial dynamin-related protein as a contributor to mitosomal morphogenesis and homeostasis. To overcome inherent limitations that have hitherto severely hampered the characterization of these unique organelles we applied a novel interaction-based proteome discovery strategy using forward and reverse protein co-immunoprecipitation. This allowed generation of organelle proteome data strictly in a protein-protein interaction context. We built an initial Tom40-centered outer membrane interactome by co-immunoprecipitation experiments, identifying small GTPases, factors with dual mitosome and endoplasmic reticulum (ER distribution, as well as novel matrix proteins. Through iterative expansion of this protein-protein interaction network, we were able to i significantly extend this interaction-based mitosomal proteome to include other membrane-associated proteins with possible roles in mitosome morphogenesis and connection to other subcellular compartments, and ii identify novel matrix proteins which may shed light on mitosome-associated metabolic functions other than Fe-S cluster biogenesis. Functional analysis also revealed conceptual conservation of protein

  12. Giardia: Illness & Symptoms

    Science.gov (United States)

    ... 683. Hill DR. Giardia lamblia . In: Gillespie SH, Pearson RD, eds. Principles and practice of clinical parasitology. ... 6348 Email CDC-INFO U.S. Department of Health & Human Services HHS/Open USA.gov Top

  13. PREVALENCE OF GIARDIA LAMBLIA AND OTHER INTESTINAL PARASITES IN PRESCHOOL CHILDREN AND ITS RELATION TO RESIDENCE PLACE, SEX AND BLOOD GROUP IN ILAM COUNTY OF IRAN

    Directory of Open Access Journals (Sweden)

    Pourbabak

    1996-06-01

    Full Text Available 1711' object of this study was to determine the prevalence oj asymptomatic infestation with Giardia lamblia lind other intestinal parasites in children of urban anti rural communities oj /lam county and its relation with dwelling place, sex and blood grollp!.. 77w study designed as (l five-month pUTasitoulgica! .m,..£!' oj fecal ami blood specimens from humans anti performed in 10 urban hcalih-trcatmcru clinics of llam city, two urban health treatment clinics of Eyvun city, two rural health-treatment clinics oj Chavar and Sartaf villages, llam province west of fran, 17,e examined population was preschool {, to 7 year-old children without any 'gastrointestinal compliarus. Prevalence oj infestation in subject grOllp W(l."' 32.54% (n=3100. Among intestinal parasites' G. lambliu with 85.43o/c (27.8% oj all, n=JO(JI prevalence rate was the most common. Infestation with 11. nnrm with 1'/.93% and E. coli with 3.07';, were in the second and third ranks, respectively, Infestation shows a distinct relationship with gender (P<0.05 and dwelling place, but it lacks a significant relation with blood groups. This study ."lIOWS that the prevalence of intestinal infestation in 6 to 7 year old child oj llam county hi equivalent to the top oj tile line oj the statistical percentage all over the world. 17,e relation between the severity oj infestation and residence place may arouse the suspicion oj sever contamination oj imbibing water.

  14. Factores de riesgo de la infección por Giardia lamblia en niños de guarderías infantiles de Ciudad de La Habana, Cuba Risk factors for Giardia lamblia in children in daycare centers in Havana, Cuba

    Directory of Open Access Journals (Sweden)

    Fidel Ángel Núñez

    2003-04-01

    Full Text Available En un estudio longitudinal sobre giardiasis desarrollado durante 18 meses en tres guarderías infantiles de Ciudad de La Habana, describimos un grupo de niños con tendencia o "predisposición" a la infección por Giardia lamblia; a los que se les encontró con síntomas clínicos más asociados a las diarreas. Este estudio de casos y controles se desarrolló para conocer si algunos factores socioeconómicos y hábitos higiénicos estaban asociados con este fenómeno. No se encontraron diferencias entre ambos grupos en las tasas de hacinamiento, el índice de personas por cama, en la carencia de determinados equipos eléctricos, en el nivel escolar de las madres, y en el promedio del ingreso familiar; sin embargo, predominó una frecuencia mayor de padres con nivel escolar menor de 12 grado en los casos que en los controles. No se encontraron diferencias entre ambos grupos en cuanto a la ausencia de lavado de manos antes de comer y después de defecar, pero se encontró un mayor porcentaje de lavado incorrecto de vegetales, y una menor frecuencia del hábito de hervir el agua de consumo en las familias de los casos. Estos resultados demuestran el papel del agua como vehículo de transmisión en la giardiasis y la importancia de algunos factores epidemiológicos.We conducted a longitudinal study on giardiasis in three daycare centers in Havana City for a period of 18 months and described a group of children with a "predisposition" or tendency towards re-infection with Giardia lamblia. This group was found to be more frequently associated with clinical symptoms such as diarrhea. A case-control study was designed to determine whether socioeconomic factors and hygiene were associated with this phenomenon. We found no differences between the groups with regard to overcrowding rates, number of persons per bed, absence of certain electric appliances, mother's schooling, or mean family income. However, there were proportionally more fathers with less

  15. Prevalence and associated risk factors for Giardia lamblia infection among children hospitalized for diarrhea in Goiânia, Goiás State, Brazil Prevalência e fatores de risco associados à infecção por Giardia lamblia em crianças hospitalizadas com diarréia em Goiânia, Goiás, Brasil

    Directory of Open Access Journals (Sweden)

    Maria das Graças Cabral Pereira

    2007-06-01

    Full Text Available The objective of this study was to determine the prevalence and to identify risk factors associated with Giardia lamblia infection in diarrheic children hospitalized for diarrhea in Goiânia, State of Goiás, Brazil. A cross-sectional study was conducted and a comprehensive questionnaire was administered to the child's primary custodian. Fixed effects logistic regression was used to determine the association between infection status for G. lamblia and host, sociodemographic, environmental and zoonotic risk factors. A total of 445 fecal samples were collected and processed by the DFA methodology, and G. lamblia cysts were present in the feces of 44 diarrheic children (9.9%. A variety of factors were found to be associated with giardiasis in these population: age of children (OR, 1.18; 90% CI, 1.0 - 1.36; p = 0.052, number of children in the household (OR 1.45; 90% CI, 1.13 - 1.86; p = 0.015, number of cats in the household (OR, 1.26; 90% CI, 1.03 -1.53; p = 0.059, food hygiene (OR, 2.9; 90% CI, 1.34 - 6.43; p = 0.024, day-care centers attendance (OR, 2.3; 90% CI, 1.20 - 4.36; p = 0.034, living on a rural farm within the past six months prior hospitalization (OR, 5.4; CI 90%, 1.5 - 20.1; p = 0.03 and the number of household adults (OR, 0.59; 90% CI, 0.42 - 0.83; p = 0.012. Such factors appropriately managed may help to reduce the annual incidence of this protozoal infection in the studied population.O objetivo desse estudo foi estimar a prevalência e identificar fatores de risco associados à infecção por Giardia lamblia em crianças hospitalizadas com diarréia no município de Goiânia, Estado de Goiás, Brasil. Foi realizado um estudo transversal e um questionário estruturado foi administrado ao responsável pela criança. Análise multivariada foi realizada por meio de regressão logística para se determinar a associação entre infecção por G. lamblia e as variáveis sociodemográficas, ambientais e zoonóticas relacionadas ao

  16. Presencia de Giardia lamblia y Cryptosporidium spp. en aguas residuales depuradas reutilizadas para riego agrícola en la isla de Tenerife, España. Efectos del transporte a larga distancia sobre la calidad del agua reutilizada

    Directory of Open Access Journals (Sweden)

    N. Abreu Acosta

    2002-06-01

    Full Text Available El empleo de aguas residuales depuradas para riego agrícola es la alternativa de reutilización con más relevancia hoy día, siempre y cuando se desarrolle con garantías sanitarias y medioambientales.Giardia lamblia y Cryptosporidium spp. son dos protozoos patógenos entéricos de amplia distribución ambiental, frecuentes en hábitats acuáticos. La investigación y detección de estos parásitos en aguas ha adquirido importancia en los últimos años debido a que poseen formas de dispersión resistentes a los tratamientos habituales, aplicados tanto en procesos de potabilización como de depuración, y a que han sido clasificados como patógenos emergentes causantes de importantes brotes de transmisión hídrica.En este trabajo se estudia la presencia de quistes de Giardia lamblia y ooquistes de Cryptosporidium spp. en el agua residual depurada de la ciudad de Santa Cruz de Tenerife que es transportada hasta el sur de la isla de Tenerife para su reutilización en agricultura. Asimismo se investiga el efecto del transporte, el almacenamiento y el tratamiento avanzado sobre la concentración de quistes y ooquistes a través del sistema, y la existencia de relaciones con otros parámetros bacteriológicos y físico-químicos.Los resultados obtenidos ponen de manifiesto comportamientos variables de los contenidos en quistes y ooquistes frente a los tratamientos aplicados, y el efecto depurador que el transporte a larga distancia, parece tener sobre el agua residual depurada.No se han encontrado relaciones entre las concentraciones de quistes y ooquistes en el agua residual depurada y el contenido de los indicadores tradicionales de contaminación fecal.

  17. Presencia de Giardia lamblia y Cryptosporidium spp. en aguas residuales depuradas reutilizadas para riego agrícola en la isla de Tenerife, España. Efectos del transporte a larga distancia sobre la calidad del agua reutilizada Giardia lamblia and Cryptosporidium spp. Presence in treated wastewater reutilised for irrigation in Tenerife island, Spain. Long-distance transport effects in the reutilised water quality

    Directory of Open Access Journals (Sweden)

    Escolástico Aguiar González

    2002-06-01

    Full Text Available El empleo de aguas residuales depuradas para riego agrícola es la alternativa de reutilización con más relevancia hoy día, siempre y cuando se desarrolle con garantías sanitarias y medioambientales.Giardia lamblia y Cryptosporidium spp. son dos protozoos patógenos entéricos de amplia distribución ambiental, frecuentes en hábitats acuáticos. La investigación y detección de estos parásitos en aguas ha adquirido importancia en los últimos años debido a que poseen formas de dispersión resistentes a los tratamientos habituales, aplicados tanto en procesos de potabilización como de depuración, y a que han sido clasificados como patógenos emergentes causantes de importantes brotes de transmisión hídrica.En este trabajo se estudia la presencia de quistes de Giardia lamblia y ooquistes de Cryptosporidium spp. en el agua residual depurada de la ciudad de Santa Cruz de Tenerife que es transportada hasta el sur de la isla de Tenerife para su reutilización en agricultura. Asimismo se investiga el efecto del transporte, el almacenamiento y el tratamiento avanzado sobre la concentración de quistes y ooquistes a través del sistema, y la existencia de relaciones con otros parámetros bacteriológicos y físico-químicos.Los resultados obtenidos ponen de manifiesto comportamientos variables de los contenidos en quistes y ooquistes frente a los tratamientos aplicados, y el efecto depurador que el transporte a larga distancia, parece tener sobre el agua residual depurada.No se han encontrado relaciones entre las concentraciones de quistes y ooquistes en el agua residual depurada y el contenido de los indicadores tradicionales de contaminación fecal.Treated wastewater use for irrigation is, nowadays, the more relevant reutilization alternative of wastewater, if it is developed with sanitary and environmental warranties.Giardia lamblia and Cryptosporidium spp. two wide distributed enteric pathogen protozoan, which are frequent in aquatic

  18. Giardia y giardiasis Giardia and giardiasis

    OpenAIRE

    Hugo D. Luján

    2006-01-01

    Giardia lamblia es un protozoario parásito que habita el intestino delgado de los seres humanos y de muchos otros vertebrados y es una de las más comunes causas de diarrea en todo el mundo. Durante su ciclo de vida Giardia sufre significativos cambios bioquímicos y morfológicos que le permiten sobrevivir en ambientes y condiciones que de otro modo lo destruirían. Para sobrevivir fuera del intestino del hospedador, los trofozoítos de Giardia se diferencian a quistes, los que se caracterizan po...

  19. Multiplex PCR detection of Cryptosporidium sp, Giardia lamblia and Entamoeba histolytica directly from dried stool samples from Guinea-Bissauan children with diarrhoea

    DEFF Research Database (Denmark)

    Mero, Sointu; Kirveskari, Juha; Antikainen, Jenni

    2017-01-01

    and specificity, while new molecular methods may provide more accurate diagnostics. In poor regions with sample storage hampered by uncertain electricity supply, research would benefit from a method capable of analysing dried stools. Methods: A real-time multiplex PCR method with internal inhibition control...... microscopy revealed a parasite in 15%, while PCR detected 62% positive for at least one parasite: 44% of the dried samples had Giardia, 23% Cryptosporidium and 0% E. histolytica. Conclusions: Our new multiplex real-time PCR for protozoa presents a sensitive method applicable to dried samples. As proof...

  20. Factores de riesgo de la infección por Giardia lamblia en niños de guarderías infantiles de Ciudad de La Habana, Cuba

    Directory of Open Access Journals (Sweden)

    Fidel Ángel Núñez

    Full Text Available En un estudio longitudinal sobre giardiasis desarrollado durante 18 meses en tres guarderías infantiles de Ciudad de La Habana, describimos un grupo de niños con tendencia o "predisposición" a la infección por Giardia lamblia; a los que se les encontró con síntomas clínicos más asociados a las diarreas. Este estudio de casos y controles se desarrolló para conocer si algunos factores socioeconómicos y hábitos higiénicos estaban asociados con este fenómeno. No se encontraron diferencias entre ambos grupos en las tasas de hacinamiento, el índice de personas por cama, en la carencia de determinados equipos eléctricos, en el nivel escolar de las madres, y en el promedio del ingreso familiar; sin embargo, predominó una frecuencia mayor de padres con nivel escolar menor de 12 grado en los casos que en los controles. No se encontraron diferencias entre ambos grupos en cuanto a la ausencia de lavado de manos antes de comer y después de defecar, pero se encontró un mayor porcentaje de lavado incorrecto de vegetales, y una menor frecuencia del hábito de hervir el agua de consumo en las familias de los casos. Estos resultados demuestran el papel del agua como vehículo de transmisión en la giardiasis y la importancia de algunos factores epidemiológicos.

  1. Factores de riesgo de la infección por Giardia lamblia en niños de guarderías infantiles de Ciudad de La Habana, Cuba

    Directory of Open Access Journals (Sweden)

    Núñez Fidel Ángel

    2003-01-01

    Full Text Available En un estudio longitudinal sobre giardiasis desarrollado durante 18 meses en tres guarderías infantiles de Ciudad de La Habana, describimos un grupo de niños con tendencia o "predisposición" a la infección por Giardia lamblia; a los que se les encontró con síntomas clínicos más asociados a las diarreas. Este estudio de casos y controles se desarrolló para conocer si algunos factores socioeconómicos y hábitos higiénicos estaban asociados con este fenómeno. No se encontraron diferencias entre ambos grupos en las tasas de hacinamiento, el índice de personas por cama, en la carencia de determinados equipos eléctricos, en el nivel escolar de las madres, y en el promedio del ingreso familiar; sin embargo, predominó una frecuencia mayor de padres con nivel escolar menor de 12 grado en los casos que en los controles. No se encontraron diferencias entre ambos grupos en cuanto a la ausencia de lavado de manos antes de comer y después de defecar, pero se encontró un mayor porcentaje de lavado incorrecto de vegetales, y una menor frecuencia del hábito de hervir el agua de consumo en las familias de los casos. Estos resultados demuestran el papel del agua como vehículo de transmisión en la giardiasis y la importancia de algunos factores epidemiológicos.

  2. Identification of variant-specific surface proteins in Giardia muris trophozoites.

    Science.gov (United States)

    Ropolo, Andrea S; Saura, Alicia; Carranza, Pedro G; Lujan, Hugo D

    2005-08-01

    Giardia lamblia undergoes antigenic variation, a process that might allow the parasite to evade the host's immune response and adapt to different environments. Here we show that Giardia muris, a related species that naturally infects rodents, possesses multiple variant-specific surface proteins (VSPs) and expresses VSPs on its surface, suggesting that it undergoes antigenic variation similar to that of G. lamblia.

  3. Identification of Variant-Specific Surface Proteins in Giardia muris Trophozoites

    OpenAIRE

    Ropolo, Andrea S.; Saura, Alicia; Carranza, Pedro G.; Lujan, Hugo D.

    2005-01-01

    Giardia lamblia undergoes antigenic variation, a process that might allow the parasite to evade the host's immune response and adapt to different environments. Here we show that Giardia muris, a related species that naturally infects rodents, possesses multiple variant-specific surface proteins (VSPs) and expresses VSPs on its surface, suggesting that it undergoes antigenic variation similar to that of G. lamblia.

  4. Giardia and Vilem Dusan Lambl

    Czech Academy of Sciences Publication Activity Database

    Lipoldová, Marie

    2014-01-01

    Roč. 8, č. 5 (2014), e2686 ISSN 1935-2735 R&D Projects: GA MŠk LH12049 Institutional support: RVO:68378050 Keywords : History of Science * Giardia lamblia * Infectious disease Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.446, year: 2014

  5. ESTIMATION OF GIARDIA CT VALUES AT HIGH PH FOR THE SURFACE WATER TREATMENT RULE

    Science.gov (United States)

    The U.S. Environmental Protection Agency currently recommends Ct (disinfectant concentration multiplied by the exposure time) values to achieve required levels of inactivation of Giardia lamblia cysts by different disinfectants including free chlorine. Current guidance covers ina...

  6. MALDI-MIS INVESTIGATIONS OF DRINKING WATER PATHOGENS--GIARDIA AND CRYPTOSPORIDIUM

    Science.gov (United States)

    The protozoan parasites, Cryptosporidium parvum and Giardia lamblia, have been responsible for numerous waterborne outbreaks of gastrointestinal illness in the United States. The 1993 cryptosporidiosis outbreak in Milwaukee affected approximately 400,000 people and resulted in o...

  7. Giardia muris infection in mice is associated with a protective interleukin 17A response and induction of peroxisome proliferator-activated receptor alpha

    NARCIS (Netherlands)

    L. Dreesen (Leentje); L. Bosscher (Lisette); K.J. Grit (Kor); B. Staels (Bart); E.W. Lubberts (Erik); E. Bauge (Eric); P. Geldhof (Peter)

    2014-01-01

    textabstractThe protozoan parasite Giardia duodenalis (Giardia lamblia) is one of the most commonly found intestinal pathogens in mammals, including humans. In the current study, a Giardia muris-mouse model was used to analyze cytokine transcription patterns and histological changes in intestinal

  8. Persistent G. lamblia impairs growth in a murine malnutrition model.

    Science.gov (United States)

    Bartelt, Luther A; Roche, James; Kolling, Glynis; Bolick, David; Noronha, Francisco; Naylor, Caitlin; Hoffman, Paul; Warren, Cirle; Singer, Steven; Guerrant, Richard

    2013-06-01

    Giardia lamblia infections are nearly universal among children in low-income countries and are syndemic with the triumvirate of malnutrition, diarrhea, and developmental growth delays. Amidst the morass of early childhood enteropathogen exposures in these populations, G. lamblia–specific associations with persistent diarrhea, cognitive deficits, stunting, and nutrient deficiencies have demonstrated conflicting results, placing endemic pediatric giardiasis in a state of equipoise. Many infections in endemic settings appear to be asymptomatic/ subclinical, further contributing to uncertainty regarding a causal link between G. lamblia infection and developmental delay. We used G. lamblia H3 cyst infection in a weaned mouse model of malnutrition to demonstrate that persistent giardiasis leads to epithelial cell apoptosis and crypt hyperplasia. Infection was associated with a Th2-biased inflammatory response and impaired growth. Malnutrition accentuated the severity of these growth decrements. Faltering malnourished mice exhibited impaired compensatory responses following infection and demonstrated an absence of crypt hyperplasia and subsequently blunted villus architecture. Concomitantly, severe malnutrition prevented increases in B220+ cells in the lamina propria as well as mucosal Il4 and Il5 mRNA in response to infection. These findings add insight into the potential role of G. lamblia as a "stunting" pathogen and suggest that, similarly, malnourished children may be at increased risk of G. lamblia– potentiated growth decrements.

  9. Giardia & Pets

    Science.gov (United States)

    ... Qual. 1999;28(6):1991-1996. DeRegnier DP, Cole L, Schupp DG, Erlandsen SL. Viability of Giardia ... updated: July 21, 2015 Content source: Centers for Disease Control and Prevention National Center for Emerging and ...

  10. A report on a case of Giardia duodenalis

    Directory of Open Access Journals (Sweden)

    Sujata Pudasaini

    2017-09-01

    Full Text Available ABSTRACTGiardia is caused by protozoa, Giardia lamblia. It is one of the most common causes of water born or food born diarrhea and it has a worldwide distribution. The prevalence is approximately 20-30% in developing countries. Giardia duodenalis is the most commonly reported intestinal protozoan in humans mainly affecting children. The infection is usually associated with malabsorption, weight loss and growth retardation.We report a case of four years old boy who presented with diarrhea and malabsorption for last 2 years. Its clinical presentation and histopathological diagnosis on duodenal biopsy is discussed.

  11. Inactivation of Giardia muris cysts by free chlorine.

    OpenAIRE

    Leahy, J G; Rubin, A J; Sproul, O J

    1987-01-01

    The chlorine resistance of cysts of the flagellate protozoan Giardia muris was examined. This organism, which is pathogenic to mice, is being considered as a model for the inactivation of the human pathogen Giardia lamblia. Excystation was used as the criterion for cyst viability. Experiments were performed at pH 5, 7, and 9 at 25 degrees C and pH 7 at 5 degrees C. Survival curves were "stepladder"-shaped, but concentration-time data generally conformed to Watson's Law. Chlorine was most effe...

  12. Evaluation of fenbendazole for treatment of Giardia infection in cats concurrently infected with Cryptosporidium parvum.

    Science.gov (United States)

    Keith, Carey L; Radecki, Steven V; Lappin, Michael R

    2003-08-01

    To determine whether fenbendazole effectively eliminates Giardia organisms from chronically infected cats that have a concurrent Cryptosporidium parvum infection. 16 clinically normal cats. Eight cats with chronic concurrent Giardia and C parvum infections received fenbendazole (50 mg/kg, PO, q 24 h) for 5 days (treatment-group cats). Feces from each cat were collected and processed 3 days weekly for 23 days after treatment. By use of an immunofluorescent assay for detection of Giardia lamblia cysts and C parvum oocysts, organism numbers were counted and scored. Fecal results from treatment-group cats were compared with those of 8 untreated cats with Giardia infection but no C parvum infection (control-group cats). Four of 8 treatment-group cats had consistently negative results for Giardia infection after treatment. These 4 cats had consistently positive results for C parvum oocysts prior to treatment and consistently negative results after treatment. One treatment-group cat had positive results for cysts on all fecal samples, and 3 treatment-group cats had 1 to 3 negative results and then resumed shedding large numbers of cysts; each of these cats had consistently positive results for C parvum oocysts. When compared with control-group cats, treatment-group cats shed less Giardia cysts during week 1 after treatment but not during week 2. Administration of fenbendazole decreases Giardia cyst shedding to less than detectable numbers in some cats. In our study, persistent C parvum infection may have been associated with failure of fenbendazole to eliminate Giardia infection.

  13. Development of species-specific rDNA probes for Giardia by multiple fluorescent in situ hybridization combined with immunocytochemical identification of cyst wall antigens.

    Science.gov (United States)

    Erlandsen, Stanley L; Jarroll, Edward; Wallis, Peter; van Keulen, Harry

    2005-08-01

    In this study, we describe the development of fluorescent oligonucleotide probes to variable regions in the small subunit of 16S rRNA in three distinct Giardia species. Sense and antisense probes (17-22 mer) to variable regions 1, 3, and 8 were labeled with digoxygenin or selected fluorochomes (FluorX, Cy3, or Cy5). Optimal results were obtained with fluorochome-labeled oligonucleotides for detection of rRNA in Giardia cysts. Specificity of fluorescent in situ hybridization (FISH) was shown using RNase digestion and high stringency to diminish the hybridization signal, and oligonucleotide probes for rRNA in Giardia lamblia, Giardia muris, and Giardia ardeae were shown to specifically stain rRNA only within cysts or trophozoites of those species. The fluorescent oligonucleotide specific for rRNA in human isolates of Giardia was positive for ten different strains. A method for simultaneous FISH detection of cysts using fluorescent antibody (genotype marker) and two oligonucleotide probes (species marker) permitted visualization of G. lamblia and G. muris cysts in the same preparation. Testing of an environmental water sample revealed the presence of FISH-positive G. lamblia cysts with a specific rDNA probe for rRNA, while negative cysts were presumed to be of animal or bird origin.

  14. Giardia Infection (Giardiasis)

    Science.gov (United States)

    ... one of the most common causes of waterborne disease in the United States. The parasites are found in backcountry streams and lakes but also in municipal water supplies, swimming pools, whirlpool spas and wells. Giardia infection can be transmitted through food and person-to-person contact. Giardia ...

  15. Immunological aspects of Giardia infections

    OpenAIRE

    Heyworth Martin F.

    2014-01-01

    Immunodeficiency, particularly antibody deficiency, predisposes to increased intensity and persistence of Giardia infections. Giardia-infected immunocompetent hosts produce serum and intestinal antibodies against Giardia trophozoites. The number of Giardia muris trophozoites, in mice with G. muris infection, is reduced by intra-duodenal administration of anti-G. muris antibody. Giardia intestinalis antigens that are recognised by human anti-trophozoite antibodies include variable (variant-spe...

  16. Occurrence and genotype characterization of Giardia duodenalis in goat kids from the Canary Islands, Spain.

    Science.gov (United States)

    Ruiz, Antonio; Foronda, Pilar; González, Jorge F; Guedes, Aránzazu; Abreu-Acosta, Néstor; Molina, José M; Valladares, Basilio

    2008-06-14

    Giardia duodenalis (syn. Giardia lamblia, Giardia intestinalis) is a wide-spread intestinal protozoa of both humans and animals. Although giardiosis in goat is commonly asymptomatic, young kids may bear an enteric disease associated with persistent diarrhoea and delayed weight gain. In the present study we have analysed the occurrence of Giardia in 315 young goat kids (2-6 months old) from Gran Canaria Island (Spain) through visualization of faecal cysts. The identification of genotypes of G. duodenalis among the farms was attained by nested PCR of the triophosphate isomerase (TPI) and single PCR of beta-giardin genes and subsequent sequencing. Positive samples were found in 42.2% of the animals and 95.5% of the farms. Goat faecal specimens were positive for only livestock-associated G. duodenalis assemblage E genotype for both TPI and beta-giardin genes. The genetic analysis of these two loci revealed the presence of different haplotypes among the farms included in the survey and high homology with homologous genes from cattle and sheep. Altogether, the data presented here provide additional information to the prevalence and genetic characterization of Giardia isolates. The absence of assemblages A and B in this study suggests that zoonotic transmission of Giardia from goats could be of low epidemiological significance, although these findings should be validated in studies including other geographical areas, age groups and larger number of samples.

  17. Giardia: General Information

    Science.gov (United States)

    ... lives in the intestines and is passed in feces (poop). Once outside the body, Giardia can sometimes survive ... changing tables, diaper pails, or toys) that contain feces (poop) from an infected person or animal Drinking ...

  18. Immunological aspects of Giardia infections.

    Science.gov (United States)

    Heyworth, Martin F

    2014-01-01

    Immunodeficiency, particularly antibody deficiency, predisposes to increased intensity and persistence of Giardia infections. Giardia-infected immunocompetent hosts produce serum and intestinal antibodies against Giardia trophozoites. The number of Giardia muris trophozoites, in mice with G. muris infection, is reduced by intra-duodenal administration of anti-G. muris antibody. Giardia intestinalis antigens that are recognised by human anti-trophozoite antibodies include variable (variant-specific) and invariant proteins. Nitric oxide (NO) appears to contribute to host clearance of Giardia trophozoites. Arginine is a precursor of NO and is metabolised by Giardia trophozoites, possibly reducing its availability for generation of NO by the host. Work with mice suggests that T lymphocytes and interleukin-6 (IL-6) contribute to clearance of Giardia infection via mechanisms independent of antibodies. © M.F. Heyworth, published by EDP Sciences, 2014.

  19. Immunological aspects of Giardia infections

    Directory of Open Access Journals (Sweden)

    Heyworth Martin F.

    2014-01-01

    Full Text Available Immunodeficiency, particularly antibody deficiency, predisposes to increased intensity and persistence of Giardia infections. Giardia-infected immunocompetent hosts produce serum and intestinal antibodies against Giardia trophozoites. The number of Giardia muris trophozoites, in mice with G. muris infection, is reduced by intra-duodenal administration of anti-G. muris antibody. Giardia intestinalis antigens that are recognised by human anti-trophozoite antibodies include variable (variant-specific and invariant proteins. Nitric oxide (NO appears to contribute to host clearance of Giardia trophozoites. Arginine is a precursor of NO and is metabolised by Giardia trophozoites, possibly reducing its availability for generation of NO by the host. Work with mice suggests that T lymphocytes and interleukin-6 (IL-6 contribute to clearance of Giardia infection via mechanisms independent of antibodies.

  20. Central importance of immunoglobulin A in host defense against Giardia spp.

    Science.gov (United States)

    Langford, T Dianne; Housley, Michael P; Boes, Marianne; Chen, Jianzhu; Kagnoff, Martin F; Gillin, Frances D; Eckmann, Lars

    2002-01-01

    The protozoan pathogen Giardia is an important cause of parasitic diarrheal disease worldwide. It colonizes the lumen of the small intestine, suggesting that effective host defenses must act luminally. Immunoglobulin A (IgA) antibodies are presumed to be important for controlling Giardia infection, but direct evidence for this function is lacking. B-cell-independent effector mechanisms also exist and may be equally important for antigiardial host defense. To determine the importance of the immunoglobulin isotypes that are transported into the intestinal lumen, IgA and IgM, for antigiardial host defense, we infected gene-targeted mice lacking IgA-expressing B-cells, IgM-secreting B-cells, or all B-cells as controls with Giardia muris or Giardia lamblia GS/M-83-H7. We found that IgA-deficient mice could not eradicate either G. muris or G. lamblia infection, demonstrating that IgA is required for their clearance. Furthermore, although neither B-cell-deficient nor IgA-deficient mice could clear G. muris infections, IgA-deficient mice controlled infection significantly better than B-cell-deficient mice, suggesting the existence of B-cell-dependent but IgA-independent antigiardial defenses. In contrast, mice deficient for secreted IgM antibodies cleared G. muris infection normally, indicating that they have no unique functions in antigiardial host defense. These data, together with the finding that B-cell-deficient mice have some, albeit limited, residual capacity to control G. muris infection, show that IgA-dependent host defenses are central for eradicating Giardia spp. Moreover, B-cell-dependent but IgA-independent and B-cell-independent antigiardial host defenses exist but are less important for controlling infection.

  1. [Investigation on contamination of Giardia and Cryptosporidium in drinking water in Jiangsu Province].

    Science.gov (United States)

    Bi-Xian, N I; Ming-Xue, S; Xiang-Zhen, X U; Xiao-Ting, W; Yang, D; Xiao-Lin, J

    2017-05-17

    Objective To know the contamination status of Giardia lamblia and Cryptosporidium in drinking water of Jiangsu Province, so as to provide the evidence for producing hygiene and safety drinking water. Methods A total of 28 water plants of 13 cities in Jiangsu Province were selected, and the source water (10 L), chlorinated water (100 L) and tap water (100 L) were collected separately in each site. The water samples were then treated by filtration, washing, centrifuging concentration, immune magnetic separation, and immunofluorescent assay, to detect the numbers of Giardia cysts and Cryptosporidium oocysts. Results Totally 84 samples from 13 cities were collected, including 28 source water, 28 chlorinated water and 28 tap water samples. Among the chlorinated water and tap water samples, no Giardia cysts and Cryptosporidium oocysts were found. However, Giardia cysts were detected in 3 (10.71%, 3/28) source water samples (Yancheng, Lianyungang, Changzhou cities), with the density of 1 cyst/10 L of all. Cryptosporidium oocysts were also detected in 3 (10.71%, 3/28) source water samples (Nanjing, Zhenjiang, Yangzhou cities), with the density of 1 oocyst/10 L of all. Conclusions The source water in partial areas of Jiangsu Province has been contaminated by Giardia and Cryptosporidium . To ensure the safety of drinking, the regulation of source water and surveillance of drinking water should be strengthened.

  2. Disruptions of Host Immunity and Inflammation by Giardia Duodenalis: Potential Consequences for Co-Infections in the Gastro-Intestinal Tract

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    James A. Cotton

    2015-11-01

    Full Text Available Giardia duodenalis (syn. G. intestinalis, or G. lamblia is a leading cause of waterborne diarrheal disease that infects hundreds of millions of people annually. Research on Giardia has greatly expanded within the last few years, and our understanding of the pathophysiology and immunology on this parasite is ever increasing. At peak infection, Giardia trophozoites induce pathophysiological responses that culminate in the development of diarrheal disease. However, human data has suggested that the intestinal mucosa of Giardia-infected individuals is devoid of signs of overt intestinal inflammation, an observation that is reproduced in animal models. Thus, our understanding of host inflammatory responses to the parasite remain incompletely understood and human studies and experimental data have produced conflicting results. It is now also apparent that certain Giardia infections contain mechanisms capable of modulating their host’s immune responses. As the oral route of Giardia infection is shared with many other gastrointestinal (GI pathogens, co-infections may often occur, especially in places with poor sanitation and/or improper treatment of drinking water. Moreover, Giardia infections may modulate host immune responses and have been found to protect against the development of diarrheal disease in developing countries. The following review summarizes our current understanding of the immunomodulatory mechanisms of Giardia infections and their consequences for the host, and highlights areas for future research. Potential implications of these immunomodulatory effects during GI co-infection are also discussed.

  3. Giardia duodenalis infection reduces granulocyte infiltration in an in vivo model of bacterial toxin-induced colitis and attenuates inflammation in human intestinal tissue.

    Directory of Open Access Journals (Sweden)

    James A Cotton

    Full Text Available Giardia duodenalis (syn. G. intestinalis, G. lamblia is a predominant cause of waterborne diarrheal disease that may lead to post-infectious functional gastrointestinal disorders. Although Giardia-infected individuals could carry as much as 106 trophozoites per centimetre of gut, their intestinal mucosa is devoid of overt signs of inflammation. Recent studies have shown that in endemic countries where bacterial infectious diseases are common, Giardia infections can protect against the development of diarrheal disease and fever. Conversely, separate observations have indicated Giardia infections may enhance the severity of diarrheal disease from a co-infecting pathogen. Polymorphonuclear leukocytes or neutrophils (PMNs are granulocytic, innate immune cells characteristic of acute intestinal inflammatory responses against bacterial pathogens that contribute to the development of diarrheal disease following recruitment into intestinal tissues. Giardia cathepsin B cysteine proteases have been shown to attenuate PMN chemotaxis towards IL-8/CXCL8, suggesting Giardia targets PMN accumulation. However, the ability of Giardia infections to attenuate PMN accumulation in vivo and how in turn this effect may alter the host inflammatory response in the intestine has yet to be demonstrated. Herein, we report that Giardia infection attenuates granulocyte tissue infiltration induced by intra-rectal instillation of Clostridium difficile toxin A and B in an isolate-dependent manner. This attenuation of granulocyte infiltration into colonic tissues paralled decreased expression of several cytokines associated with the recruitment of PMNs. Giardia trophozoite isolates that attenuated granulocyte infiltration in vivo also decreased protein expression of cytokines released from inflamed mucosal biopsy tissues collected from patients with active Crohn's disease, including several cytokines associated with PMN recruitment. These results demonstrate for the first time

  4. Batch solar disinfection inactivates oocysts of Cryptosporidium parvum and cysts of Giardia muris in drinking water.

    Science.gov (United States)

    McGuigan, K G; Méndez-Hermida, F; Castro-Hermida, J A; Ares-Mazás, E; Kehoe, S C; Boyle, M; Sichel, C; Fernández-Ibáñez, P; Meyer, B P; Ramalingham, S; Meyer, E A

    2006-08-01

    To determine whether batch solar disinfection (SODIS) can be used to inactivate oocysts of Cryptosporidium parvum and cysts of Giardia muris in experimentally contaminated water. Suspensions of oocysts and cysts were exposed to simulated global solar irradiation of 830 W m(-2) for different exposure times at a constant temperature of 40 degrees C. Infectivity tests were carried out using CD-1 suckling mice in the Cryptosporidium experiments and newly weaned CD-1 mice in the Giardia experiments. Exposure times of > or =10 h (total optical dose c. 30 kJ) rendered C. parvum oocysts noninfective. Giardia muris cysts were rendered completely noninfective within 4 h (total optical dose >12 kJ). Scanning electron microscopy and viability (4',6-diamidino-2-phenylindole/propidium iodide fluorogenic dyes and excystation) studies on oocysts of C. parvum suggest that inactivation is caused by damage to the oocyst wall. Results show that cysts of G. muris and oocysts of C. parvum are rendered completely noninfective after batch SODIS exposures of 4 and 10 h (respectively) and is also likely to be effective against waterborne cysts of Giardia lamblia. These results demonstrate that SODIS is an appropriate household water treatment technology for use as an emergency intervention in aftermath of natural or man-made disasters against not only bacterial but also protozoan pathogens.

  5. Detection of small number of Giardia in biological materials prepared from stray dogs.

    Science.gov (United States)

    Esmailikia, Leila; Ebrahimzade, Elahe; Shayan, Parviz; Amininia, Narges

    2017-12-20

    Giardia lamblia is an intestinal protozoa with intermittent and low shedding especially in dogs, and the detection of Giardia is accompanied with problems such as sampling and diagnostic method. The objective of this study was to detection of Giardia in biological materials with low number of parasite using parasitological and molecular methods, and also to determine whether the examined stray dogs harbor known zoonotic genotype of Giardia. For this aim 85 fecal and duodenal samples were studied from which 1 was positive by Trichrome staining of stool, 4 were positive by staining of duodenal samples. The nested PCR analysis with primers derived from 18 SrRNA showed that the specific PCR product could be amplified in 4 stool and 4 duodenal samples. All positive samples in staining analysis were also positive in nested PCR. No amplification could be observed by nested PCR with primers derived from β giardin gene due to the single copy of gene. Interestingly, the extracted DNA from old fixed stained Giardia positive smears could be also amplified with primers derived from 18SrRNA gene. The sequence analysis of nested PCR products showed that they belong to the genotype D. In conclusion, it is to denote that the Trichrome or Giemsa methods were not suitable for the detection of small number of this parasite in stool and the nested PCR with primers derived from 18S rRNA gene can replace the traditional methods successfully. For detection of Giardia in stool, primers derived from β giardin will not be recommended.

  6. Asociación de enfermedad de Whipple e infección por Giardia lamblia

    OpenAIRE

    Gil Ruiz, J. A.; Gil Simón, P.; Aparicio Duque, R.; Mayor Jerez, J. L.

    2005-01-01

    Whipple'disease is mainly characterized by affecting the digestive system, although it can be a multisystemic process with different clinical symptoms. The bacillus causing the disease has been isolated and cultivated in 2000 and the genome sequence has been recently analyzed in 2003, which means new perspectives for its diagnosis and treatment. Giardiasis is an infestation caused by a protozoo and may cause a malabsorption syndrome or run in a subclinic way. The case of a middle-aged male is...

  7. Cloning and restriction enzyme mapping of ribosomal DNA of Giardia duodenalis, Giardia ardeae and Giardia muris.

    Science.gov (United States)

    van Keulen, H; Campbell, S R; Erlandsen, S L; Jarroll, E L

    1991-06-01

    In an attempt to study Giardia at the DNA sequence level, the rRNA genes of three species, Giardia duodenalis, Giardia ardeae and Giardia muris were cloned and restriction enzyme maps were constructed. The rDNA repeats of these Giardia show completely different restriction enzyme recognition patterns. The size of the rDNA repeat ranges from approximately 5.6 kb in G. duodenalis to 7.6 kb in both G. muris and G. ardeae. These size differences are mainly attributable to the variation in length of the spacer. Minor differences exist among these Giardia in the sizes of their small subunit rRNA and the internal transcribed spacer between small and large subunit rRNA. The genetic maps were constructed by sequence analysis of the DNA around the 5' and 3' ends of the mature rRNA genes and between the rRNA covering the 5.8S rRNA gene and internal transcribed spacer. Comparison of the 5.8S rDNA and 3' end of large subunit rDNA from these three Giardia species showed considerable sequence variation, but the rDNA sequences of G. duodenalis and G. ardeae appear more closely related to each other than to G. muris.

  8. Polymeric immunoglobulin receptor in intestinal immune defense against the lumen-dwelling protozoan parasite Giardia.

    Science.gov (United States)

    Davids, Barbara J; Palm, J E Daniel; Housley, Michael P; Smith, Jennifer R; Andersen, Yolanda S; Martin, Martin G; Hendrickson, Barbara A; Johansen, Finn-Eirik; Svärd, Staffan G; Gillin, Frances D; Eckmann, Lars

    2006-11-01

    The polymeric Ig receptor (pIgR) is conserved in mammals and has an avian homologue, suggesting evolutionarily important functions in vertebrates. It transports multimeric IgA and IgM across polarized epithelia and is highly expressed in the intestine, yet little direct evidence exists for its importance in defense against common enteric pathogens. In this study, we demonstrate that pIgR can play a critical role in intestinal defense against the lumen-dwelling protozoan parasite Giardia, a leading cause of diarrheal disease. The receptor was essential for the eradication of Giardia when high luminal IgA levels were required. Clearance of Giardia muris, in which IgA plays a dominant role, was severely compromised in pIgR-deficient mice despite significant fecal IgA output at 10% of normal levels. In contrast, eradication of the human strain Giardia lamblia GS/M, for which adaptive immunity is less IgA dependent in mice, was unaffected by pIgR deficiency, indicating that pIgR had no physiologic role when lower luminal IgA levels were sufficient for parasite elimination. Immune IgA was greatly increased in the serum of pIgR-deficient mice, conferred passive protection against Giardia, and recognized several conserved giardial Ags, including ornithine carbamoyltransferase, arginine deiminase, alpha-enolase, and alpha- and beta-giardins, that are also detected in human giardiasis. Corroborative observations were made in mice lacking the J chain, which is required for pIgR-dependent transepithelial IgA transport. These results, together with prior data on pIgR-mediated immune neutralization of luminal cholera toxin, suggest that pIgR is essential in intestinal defense against pathogenic microbes with high-level and persistent luminal presence.

  9. Estudio de la expresión de calmodulina y detección de posibles cambios en transducción de señales durante los procesos de diferenciación del parásito Giardia intestinalis / Study of calmodulin expression and detection of changes in signal transduction pathways during the differentiation processes of parasite Giardia intestinalis

    OpenAIRE

    Alvarado Mora, Magda Elvira

    2009-01-01

    Giardia intestinalis es un parásito que infecta humanos. El proceso de exquistación es fundamental para que Giardia pueda infectar a un nuevo hospedero. Es un proceso biológico muy interesante, en donde la forma dormitante (quiste) detecta que las condiciones ambientales son las adecuadas para la reactivación celular. En este trabajo se estableció un método para la purificación de quistes del parásito, y se realizaron experimentos de exquistación. Se analizaron cambios en el patrón de fosfori...

  10. Giardia muris and Giardia duodenalis groups: ultrastructural differences between the trophozoites

    OpenAIRE

    Sogayar,Maria Inês L.; Gregório,Elisa Aparecida

    1989-01-01

    Trophozoites of the Giardia muris group from hamsters, domestic rats and mice and of the Giardia duodenalis group from hamsters and domestic rats were examined by transmission electron microscopy. The basic ultrastructure of the trophozoites was similar. Differences were shown in the morphology of the ventrolateral flange of the trophozoites of Giardia muris and Giardia duodenalis groups. Marginal plates are less developed in the species of the Giardia duodenalis group. In this group, the dis...

  11. Genome analysis and comparative genomics of a Giardia intestinalis assemblage E isolate

    Directory of Open Access Journals (Sweden)

    Andersson Jan O

    2010-10-01

    Full Text Available Abstract Background Giardia intestinalis is a protozoan parasite that causes diarrhea in a wide range of mammalian species. To further understand the genetic diversity between the Giardia intestinalis species, we have performed genome sequencing and analysis of a wild-type Giardia intestinalis sample from the assemblage E group, isolated from a pig. Results We identified 5012 protein coding genes, the majority of which are conserved compared to the previously sequenced genomes of the WB and GS strains in terms of microsynteny and sequence identity. Despite this, there is an unexpectedly large number of chromosomal rearrangements and several smaller structural changes that are present in all chromosomes. Novel members of the VSP, NEK Kinase and HCMP gene families were identified, which may reveal possible mechanisms for host specificity and new avenues for antigenic variation. We used comparative genomics of the three diverse Giardia intestinalis isolates P15, GS and WB to define a core proteome for this species complex and to identify lineage-specific genes. Extensive analyses of polymorphisms in the core proteome of Giardia revealed differential rates of divergence among cellular processes. Conclusions Our results indicate that despite a well conserved core of genes there is significant genome variation between Giardia isolates, both in terms of gene content, gene polymorphisms, structural chromosomal variations and surface molecule repertoires. This study improves the annotation of the Giardia genomes and enables the identification of functionally important variation.

  12. Unique phylogenetic position of Diplomonadida based on the complete small subunit ribosomal RNA sequence of Giardia ardeae, G. muris, G. duodenalis and Hexamita sp.

    Science.gov (United States)

    van Keulen, H; Gutell, R R; Gates, M A; Campbell, S R; Erlandsen, S L; Jarroll, E L; Kulda, J; Meyer, E A

    1993-01-01

    Complete small-subunit rRNA (SSU-rRNA) coding region sequences were determined for two species of the intestinal parasite Giardia: G. ardeae and G. muris, both belonging to the order Diplomonadida, and a free-living member of this order, Hexamita sp. These sequences were compared to published SSU-rDNA sequences from a third member of the genus Giardia, G. duodenalis (often called G. intestinalis or G. lamblia) and various representative organisms from other taxa. Of the three Giardia sequences analyzed, the SSU-rRNA from G. muris is the smallest (1432 bases as compared to 1435 and 1453 for G. ardeae and G. duodenalis, respectively) and has the lowest G+C content (58.9%). The Hexamita SSU-rRNA is the largest in this group, containing 1550 bases. Because the sizes of the SSU-rRNA are prokaryotic rather than typically eukaryotic, the secondary structures of the SSU-rRNAs were constructed. These structures show a number of typically eukaryotic signature sequences. Sequence alignments based on constraints imposed by secondary structure were used for construction of a phylogenetic tree for these four taxa. The results show that of the four diplomonads represented, the Giardia species form a distinct group. The other diplomonad Hexamita and the microsporidium Vairimorpha necatrix appear to be distinct from Giardia.

  13. Novel lineages of Giardia intestinalis identified by genetic analysis of organisms isolated from dogs in Australia.

    Science.gov (United States)

    Monis, P T; Andrews, R H; Mayrhofer, G; Mackrill, J; Kulda, J; Isaac-Renton, J L; Ey, P L

    1998-01-01

    Infection of suckling mice with Giardia trophozoites recovered from the intestines of 11 dogs autopsied in Central and Southern Australia in each case produced an established isolate. In contrast, only 1 isolate was obtained by inoculation of faecal cysts. The organisms grew poorly in comparison with isolates from humans or non-canine animal hosts. Light microscopy revealed that the trophozoites had median bodies with the 'claw hammer' appearance typical of G. intestinalis (syn. G. duodenalis, G. lamblia) but that they differed in shape and nuclear morphology from axenic isolates of human or canine origin. Allozymic analysis of electrophoretic data representing 26 loci and phylogenetic analysis of nucleotide sequences obtained from DNA amplified from the glutamate dehydrogenase locus showed that the 11 isolates examined from Australian dogs were genetically distinct from all isolates of G. intestinalis that have been established previously from humans and animals, and also from G. muris. Both analytical methods placed 10 of the Australian canine isolates into a unique genetic lineage (designated Assemblage C) and the eleventh into a deep-rooted second branch (designated Assemblage D), each well separated from the 2 lineages (Assemblages A and B) of G. intestinalis that encompass all the genotypes known to infect humans. In contrast, 4 axenic isolates derived from dogs in Canada and Europe (the only other isolates to have been established from dogs) have genotypes characteristic of genetic Assemblages A or B. The findings indicate that the novel Giardia identified in these rural Australian dogs have a restricted host range, possibly confined to canine species. The poor success rate in establishing Giardia from dogs in vitro suggests, further, that similar genotypes may predominate as canine parasites world-wide. The absence of such organisms among isolates of Giardia that have been established from humans by propagation in suckling mice indicates that they are

  14. Changes in intestinal fluid and mucosal immune responses to cholera toxin in Giardia muris infection and binding of cholera toxin to Giardia muris trophozoites.

    Science.gov (United States)

    Ljungström, I; Holmgren, J; Svennerholm, A M; Ferrante, A

    1985-10-01

    The effect of Giardia muris infection on the diarrheal response and gut mucosal antibody response to cholera toxin was examined in mice. The results obtained showed that the fluid accumulation in intestinal loops exposed to cholera toxin was increased in mice infected with a low number (5 X 10(4) ) of G. muris cysts compared with the response in noninfected mice. This effect was associated with a marked reduction in absorption of oral rehydration fluid from the intestine. In contrast, mice infected with a high dose (2 X 10(5) ) of cysts showed a marked decrease in fluid accumulation in response to the toxin. This decrease might be related to the finding that both G. muris and Giardia lamblia trophozoites can bind significant amounts of cholera toxin. Evidence is presented which suggests that the gut mucosal antibody response, mainly immunoglobulin A but also immunoglobulin G, to an immunization course with perorally administered cholera toxin was depressed in mice infected with G. muris. The reduction in antibody levels was particularly evident when the primary immunization was made very early after infection. The serum antitoxin antibodies to the oral immunization with cholera toxin were, however, not affected. Likewise, the delayed-type hypersensitivity response against sheep erythrocytes in animals primed subcutaneously with sheep erythrocytes was not modified during the course of G. muris infection.

  15. Division of Giardia isolates from humans into two genetically distinct assemblages by electrophoretic analysis of enzymes encoded at 27 loci and comparison with Giardia muris.

    Science.gov (United States)

    Mayrhofer, G; Andrews, R H; Ey, P L; Chilton, N B

    1995-07-01

    Giardia that infect humans are known to be heterogeneous but they are assigned currently to a single species, Giardia intestinalis (syn. G. lamblia). The genetic differences that exist within G. intestinalis have not yet been assessed quantitatively and neither have they been compared in magnitude with those that exist between G. intestinalis and species that are morphologically similar (G. duodenalis) or morphologically distinct (e.g. G. muris). In this study, 60 Australian isolates of G. intestinalis were analysed electrophoretically at 27 enzyme loci and compared with G. muris and a feline isolate of G. duodenalis. Isolates of G. intestinalis were distinct genetically from both G. muris (approximately 80% fixed allelic differences) and the feline G. duodenalis isolate (approximately 75% fixed allelic differences). The G. intestinalis isolates were extremely heterogeneous but they fell into 2 major genetic assemblages, separated by fixed allelic differences at approximately 60% of loci examined. The magnitude of the genetic differences between the G. intestinalis assemblages approached the level that distinguished the G. duodenalis isolate from the morphologically distinct G. muris. This raises important questions about the evolutionary relationships of the assemblages with Homo sapiens, the possibility of ancient or contemporary transmission from animal hosts to humans and the biogeographical origins of the two clusters.

  16. Ubiquitination dynamics in the early-branching eukaryote Giardia intestinalis

    Science.gov (United States)

    Niño, Carlos A; Chaparro, Jenny; Soffientini, Paolo; Polo, Simona; Wasserman, Moises

    2013-01-01

    Ubiquitination is a highly dynamic and versatile posttranslational modification that regulates protein function, stability, and interactions. To investigate the roles of ubiquitination in a primitive eukaryotic lineage, we utilized the early-branching eukaryote Giardia intestinalis. Using a combination of biochemical, immunofluorescence-based, and proteomics approaches, we assessed the ubiquitination status during the process of differentiation in Giardia. We observed that different types of ubiquitin modifications present specific cellular and temporal distribution throughout the Giardia life cycle from trophozoites to cyst maturation. Ubiquitin signal was detected in the wall of mature cysts, and enzymes implicated in cyst wall biogenesis were identified as substrates for ubiquitination. Interestingly, inhibition of proteasome activity did not affect trophozoite replication and differentiation, while it caused a decrease in cyst viability, arguing for proteasome involvement in cyst wall maturation. Using a proteomics approach, we identified around 200 high-confidence ubiquitinated candidates that vary their ubiquitination status during differentiation. Our results indicate that ubiquitination is critical for several cellular processes in this primitive eukaryote. PMID:23613346

  17. Epidemiology of equine Cryptosporidium and Giardia infections.

    Science.gov (United States)

    Xiao, L; Herd, R P

    1994-01-01

    Prevalence and infection patterns of Cryptosporidium and Giardia infections in horses were studied by a direct immunofluorescence staining method. Faecal examinations of 222 horses of different age groups revealed Cryptosporidium infection rates of 15-31% in 66 foals surveyed in central Ohio, southern Ohio and central Kentucky, USA. Only 1 of 39 weanlings, 0 of 46 yearlings, and 0 of 71 mares were positive. Giardia infection was found in all age groups, although the infection rates for foals were higher (17-35%). Chronological study of infection in 35 foals showed that foals started to excrete Cryptosporidium oocysts between 4 and 19 weeks and Giardia cysts between 2 and 22 weeks of age. The cumulative infection rates of Cryptosporidium and Giardia in foals were each 71%. Some foals were concurrently infected with both parasites and excretion of oocysts or cysts was intermittent and long-lasting. The longest duration of excretion was 14 weeks for Cryptosporidium and 16 weeks for Giardia. Excretion of Cryptosporidium oocysts stopped before weaning, while excretion of Giardia cysts continued thereafter. Infected foals were considered the major source of Cryptosporidium infection in foals, whereas infected mares were deemed the major source of Giardia infection in foals. The high infection rate of Giardia in nursing mares suggested a periparturient relaxation of immunity. The results indicated that Cryptosporidium and Giardia infections are common in horses.

  18. Giardia muris trophozoite antigenic targets for mouse intestinal IgA antibody.

    Science.gov (United States)

    Heyworth, M F; Vergara, J A

    1994-02-01

    The aim of this work was to characterize Giardia muris trophozoite proteins that are targets for intestinal anti-trophozoite IgA in G. muris-infected mice. Intestinal secretions were obtained from immunocompetent BALB/c mice that had been infected with G. muris cysts 4-5 weeks previously and from control uninfected BALB/c mice. Flow cytometry of G. muris trophozoites that had been incubated with intestinal secretions and with fluorescein isothiocyanate-conjugated anti-mouse IgA showed that anti-trophozoite IgA was present in intestinal secretions obtained from infected BALB/c mice. By immunoblotting on G. muris trophozoite proteins separated by one-dimensional gel electrophoresis, this IgA recognized at least one trophozoite protein of molecular mass of approximately 80 kDa. The 80-kDa G. muris protein(s) has a molecular mass similar to that described for cysteine-rich surface proteins of the human parasite Giardia lamblia.

  19. Giardia muris and Giardia duodenalis groups: ultrastructural differences between the trophozoites.

    Science.gov (United States)

    Sogayar, M I; Gregório, E A

    1989-01-01

    Trophozoites of the Giardia muris group from hamsters, domestic rats and mice and of the Giardia duodenalis group from hamsters and domestic rats were examined by transmission electron microscopy. The basic ultrastructure of the trophozoites was similar. Differences were shown in the morphology of the ventrolateral flange of the trophozoites of Giardia muris and Giardia duodenalis groups. Marginal plates are less developed in the species of the Giardia duodenalis group. In this group, the distal extremity of the lateral flange is short and thick and the marginal plate does not penetrate into the distal extremity of the flange. In the Giardia muris group, the ventro-lateral flange is well developed and narrow and the marginal plate penetrates the distal extremity of the flange. The osmiophilic lamella, which accompanies the dorsal surface of the marginal plate is seen only in the Giardia muris group.

  20. Giardia muris and Giardia duodenalis groups: ultrastructural differences between the trophozoites

    Directory of Open Access Journals (Sweden)

    Maria Inês L. Sogayar

    1989-08-01

    Full Text Available Trophozoites of the Giardia muris group from hamsters, domestic rats and mice and of the Giardia duodenalis group from hamsters and domestic rats were examined by transmission electron microscopy. The basic ultrastructure of the trophozoites was similar. Differences were shown in the morphology of the ventrolateral flange of the trophozoites of Giardia muris and Giardia duodenalis groups. Marginal plates are less developed in the species of the Giardia duodenalis group. In this group, the distal extremity of the lateral flange is short and thick and the marginal plate does not penetrate into the distal extremity of the flange. In the Giardia muris group, the ventro-lateral flange is well developed and narrow and the marginal plate penetrates the distal extremity of the flange. The osmiophilic lamella, which accompanies the dorsal surface of the marginal plate is seen only in the Giardia muris group.

  1. The efficacy of potassium ferrate as a chemical disinfectant on E. coli, Vibrio cholera, human adenovirus, and Giardia lamblia

    Science.gov (United States)

    Introduction: Drinking water and wastewater go through numerous treatments to remove microorganisms and other contaminants one of many processes along the treatment train is disinfection. There are different ways to disinfect these waters, however to date the most common disinf...

  2. The efficacy of potassium ferrate as a chemical disinfectant on E. coli, Vibrio cholera, human adenovirus, and Giardia lamblia - Abstract

    Science.gov (United States)

    Introduction: Drinking water and wastewater effluents go through numerous treatments to remove microorganisms and other contaminants in the United States. One of many processes along the treatment train is disinfection, and to date the most common disinfectants still remain chemi...

  3. IL-17A promotes protective IgA responses and expression of other potential effectors against the lumen-dwelling enteric parasite Giardia.

    Science.gov (United States)

    Dann, Sara M; Manthey, Carolin F; Le, Christine; Miyamoto, Yukiko; Gima, Lauren; Abrahim, Andrew; Cao, Anthony T; Hanson, Elaine M; Kolls, Jay K; Raz, Eyal; Cong, Yingzi; Eckmann, Lars

    2015-09-01

    Giardia lamblia is a leading protozoan cause of diarrheal disease worldwide. It colonizes the lumen and epithelial surface of the small intestine, but does not invade the mucosa. Acute infection causes only minimal mucosal inflammation. Effective immune defenses exist, yet their identity and mechanisms remain incompletely understood. Interleukin (IL)-17A has emerged as an important cytokine involved in inflammation and antimicrobial defense against bacterial pathogens at mucosal surfaces. In this study, we demonstrate that IL-17A has a crucial function in host defense against Giardia infection. Using murine infection models with G. muris and G. lamblia, we observed marked and selective induction of intestinal IL-17A with peak expression after 2 weeks. Th17 cells in the lamina propria and innate immune cells in the epithelial compartment of the small intestine were responsible for the IL-17A response. Experiments in gene-targeted mice revealed that the cytokine, and its cognate receptor IL-17RA, were required for eradication of the parasite. The actions of the cytokine were mediated by hematopoietic cells, and were required for the transport of IgA into the intestinal lumen, since IL-17A deficiency led to marked reduction of fecal IgA levels, as well as for increased intestinal expression of several other potential effectors, including β-defensin 1 and resistin-like molecule β. In contrast, intestinal hypermotility, another major antigiardial defense mechanism, was not impacted by IL-17A loss. Taken together, these findings demonstrate that IL-17A and IL-17 receptor signaling are essential for intestinal defense against the important lumen-dwelling intestinal parasite Giardia. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Prevalence of Irritable Bowel Syndrome and Chronic Fatigue 10 Years After Giardia Infection.

    Science.gov (United States)

    Litleskare, Sverre; Rortveit, Guri; Eide, Geir Egil; Hanevik, Kurt; Langeland, Nina; Wensaas, Knut-Arne

    2018-03-06

    Irritable bowel syndrome (IBS) is a complication that can follow gastrointestinal infection, but it is not clear if patients also develop chronic fatigue. We investigated the prevalence and odds ratio of IBS and chronic fatigue 10 years after an outbreak of Giardia lamblia, compared with a control cohort, and changes in prevalence over time. We performed a prospective follow-up study of 1252 laboratory-confirmed cases of giardiasis (exposed), which developed in Bergen, Norway in 2004. Statistics Norway provided us with information from 2504 unexposed individuals from Bergen, matched by age and sex (controls). Questionnaires were mailed to participants 3, 6, and 10 years after the outbreak. Results from the 3- and 6-year follow-up analyses have been published previously. We report the 10-year data and changes in prevalence among time points, determined by logistic regression using generalized estimating equations. The prevalence of IBS 10 years after the outbreak was 43% (n = 248) among 576 exposed individuals and 14% (n = 94) among 685 controls (adjusted odds ratio for development of IBS in exposed individuals, 4.74; 95% CI, 3.61-6.23). At this time point, the prevalence of chronic fatigue was 26% (n = 153) among 587 exposed individuals and 11% (n = 73) among 692 controls (adjusted odds ratio, 3.01; 95% CI, 2.22-4.08). The prevalence of IBS among exposed persons did not change significantly from 6 years after infection (40%) to 10 years after infection (43%; adjusted odds ratio for the change 1.03; 95% CI, 0.87-1.22). However, the prevalence of chronic fatigue decreased from 31% at 6 years after infection to 26% at 10 years after infection (adjusted odds ratio for the change 0.74; 95% CI, 0.61-0.90). The prevalence of IBS did not change significantly from 6 years after an outbreak of Giardia lamblia infection in Norway to 10 years after. However, the prevalence of chronic fatigue decreased significantly from 6 to 10 years afterward. IBS and chronic fatigue were

  5. Identification of Zoonotic Genotypes of Giardia duodenalis

    DEFF Research Database (Denmark)

    Sprong, H.; Cacciò, S.M.; van der Giessen, J.W.B

    2009-01-01

    Giardia duodenalis, originally regarded as a commensal organism, is the etiologic agent of giardiasis, a gastrointestinal disease of humans and animals. Giardiasis causes major public and veterinary health concerns worldwide. Transmission is either direct, through the faecal-oral route, or indirect......, through ingestion of contaminated water or food. Genetic characterization of G. duodenalis isolates has revealed the existence of seven groups (assemblages A to G) which differ in their host distribution. Assemblages A and B are found in humans and in many other mammals, but the role of animals......, mixtures of genotypes in individual isolates were repeatedly observed. Possible explanations are the uptake of genetically different Giardia cysts by a host, or subsequent infection of an already infected host, likely without overt symptoms, with a different Giardia species, which may cause disease. Other...

  6. Giardia muris infection in mice is associated with a protective interleukin 17A response and induction of peroxisome proliferator-activated receptor alpha.

    Science.gov (United States)

    Dreesen, Leentje; De Bosscher, Karolien; Grit, Grietje; Staels, Bart; Lubberts, Erik; Bauge, Eric; Geldhof, Peter

    2014-08-01

    The protozoan parasite Giardia duodenalis (Giardia lamblia) is one of the most commonly found intestinal pathogens in mammals, including humans. In the current study, a Giardia muris-mouse model was used to analyze cytokine transcription patterns and histological changes in intestinal tissue at different time points during infection in C57BL/6 mice. Since earlier work revealed the upregulation of peroxisome proliferator-activated receptors (PPARs) in Giardia-infected calves, a second aim was to investigate the potential activation of PPARs in the intestines of infected mice. The most important observation in all mice was a strong upregulation of il17a starting around 1 week postinfection. The significance of interleukin 17A (IL-17A) in orchestrating a protective immune response was further demonstrated in an infection trial or experiment using IL-17 receptor A (IL-17RA) knockout (KO) mice: whereas in wild-type (WT) mice, cyst secretion dropped significantly after 3 weeks of infection, the IL-17RA KO mice were unable to clear the infection. Analysis of the intestinal response further indicated peroxisome proliferator-activated receptor alpha (PPARα) induction soon after the initial contact with the parasite, as characterized by the transcriptional upregulation of ppara itself and several downstream target genes such as pltp and cpt1. Overall, PPARα did not seem to have any influence on the immune response against G. muris, since PPARα KO animals expressed il-17a and could clear the infection similar to WT controls. In conclusion, this study shows for the first time the importance of IL-17 production in the clearance of a G. muris infection together with an early induction of PPARα. The effect of the latter, however, is still unclear. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  7. Molecular characterization of Giardia duodenalis in Yemen.

    Science.gov (United States)

    Alyousefi, Naela A; Mahdy, Mohammed A K; Xiao, Lihua; Mahmud, Rohela; Lim, Yvonne A L

    2013-06-01

    Giardia duodenalis is an important intestinal protozoan in Yemen with infection rates ranging from 18% to 27%. To date, there has been no genotyping study to provide a better understanding of the transmission dynamic. This study was conducted to genotype and subtype G. duodenalis in Yemen. Stool samples were collected from 503 Yemeni outpatients between 1 and 80 years old, including 219 males and 284 females. Giardia cysts were detected via microscopy after the formal-ether concentration. Genotyping of Giardia was carried out using PCR and sequence analysis of the 16s rRNA and b-giardin genes. Of the 89 microscopy-positive Giardia samples, 65 were successfully sequenced, of which 66% (43 of 65) were identified as G. duodenalis assemblage A and 34% (22 of 65) as assemblage B. Further subtyping analysis based on b-giardin gene identified the presence of subtypes A2 and A3, which belong to the anthroponotic sub-assemblage AII. Data of the study suggest that anthroponotic transmission played a potential role in the transmission of giardiasis in the community. However, further genotyping and subtyping studies of specimens from humans and animals living in the same households are needed for a more definitive understanding of giardiasis transmission in Yemen. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Prevalence of Cryptosporidium species and Giardia intestinalis ...

    African Journals Online (AJOL)

    Cryptosporidium species and Giardia intestinalis cause diarrheal infections in humans and other vertebrate animals globally and are considered to be of great public health importance. The study was conducted to determine the prevalence Cryptosporidium species and G. intestinalis infections among patients attending ...

  9. Emissie van Cryptosporidium en Giardia door landbouwhuisdieren

    NARCIS (Netherlands)

    Schrijven JF; Bruin HAM de; Engels GB; Leenen EJTM; MGB

    1999-01-01

    In this study, the relative contributions of the pathogenic protozoa Cryptosporidium and Giardia by manure of farm animals in The Netherlands to the total yearly environmental load was studied. Manure of veal calves forms a very large source of Cryptosporidium (1.5 m 10 square 16 oocysts per year)

  10. Emissie van Cryptosporidium en Giardia door landbouwhuisdieren

    NARCIS (Netherlands)

    Schrijven JF; Bruin HAM de; Engels GB; Leenen EJTM; MGB

    1999-01-01

    Het hier gepresenteerde deelonderzoek richt zich op de relatieve bijdrage van verschillende populaties landbouwhuisdieren via mest en afvalwater aan de totale emissie van Cryptosporidium en Giardia in Nederland. Vleeskalveren vormen per jaar in Nederland via hun mest een grote emissiebron van

  11. Protection of mice against Giardia muris infection.

    Science.gov (United States)

    Roberts-Thomson, I C; Mitchell, G F

    1979-01-01

    Strains of mice showing relatively rapid (BALB/c) and defective (C3H/He) spontaneous elimination of Giardia muris displayed marked differences in the degree of resistance to infection induced by prior injection of trophozoites in Freund complete adjuvant. PMID:468385

  12. Regulation of carbohydrate metabolism during Giardia encystment

    NARCIS (Netherlands)

    Vliegenthart, J.F.G.; Jarroll, E.L.; Macechko, P.T.; Steimle, P.A.; Bulik, D.; Karr, C.D.; Keulen, Harry van; Paget, P.A.

    2001-01-01

    Giardia intestinalis trophozoites encyst when they are exposed to bile. During encystment, events related to the inducible synthesis of a novel N-acetyl-d-galactosamine (GalNAc) homopolymer, occur. Within the first 6 h of encystment, mRNA for glucosamine 6-P isomerase (GPI), the first inducible

  13. Current status and future trends in Cryptosporidium and Giardia epidemiology in Malaysia.

    Science.gov (United States)

    Lim, Y A L; Ahmad, R A; Smith, H V

    2008-06-01

    Cryptosporidium and Giardia are major causes of diarrhoeal diseases of humans worldwide, and are included in the World Health Organisation's 'Neglected Diseases Initiative'. Cryptosporidium and Giardia occur commonly in Malaysian human and non-human populations, but their impact on disease, morbidity and cost of illness is not known. The commonness of contributions from human (STW effluents, indiscriminate defaecation) and non-human (calving, lambing, muck spreading, slurry spraying, pasturing/grazing of domestic animals, infected wild animals) hosts indicate that many Malaysian environments, particularly water and soil, are sufficiently contaminated to act as potential vehicles for the transmission of disease. To gain insight into the morbidity and mortality caused by human cryptosporidiosis and giardiasis, they should be included into differential diagnoses, and routine laboratory testing should be performed and (as for many infectious diseases) reported to a centralised public health agency. To understand transmission routes and the significance of environmental contamination better will require further multidisciplinary approaches and shared resources, including raising national perceptions of the parasitological quality of drinking water. Here, the detection of Cryptosporidium and Giardia should be an integral part of the water quality requirement. A multidisciplinary approach among public health professionals in the water industry and other relevant health- and environment-associated agencies is also required in order to determine the significance of Cryptosporidium and Giardia contamination of Malaysian drinking water. Lastly, adoption of validated methods to determine the species, genotype and subgenotype of Cryptosporidium and Giardia present in Malaysia will assist in developing effective risk assessment, management and communication models.

  14. Molecular identification of Giardia and Cryptosporidium from dogs and cats

    Directory of Open Access Journals (Sweden)

    Sotiriadou Isaia

    2013-01-01

    Full Text Available The aim of the present study was to diagnose the presence of Giardia cysts and Cryptosporidium oocysts in household animals using nested polymerase chain reaction (PCR and sequence analysis. One hundred faecal samples obtained from 81 dogs and 19 cats were investigated. The Cryptosporidium genotypes were determined by sequencing a fragment of the small subunit (SSU rRNA gene, while the Giardia Assemblages were determined through analysis of the glutamate dehydrogenase (GDH locus. Isolates from five dogs and two cats were positive by PCR for the presence of Giardia, and their sequences matched the zoonotic Assemblage A of Giardia. Cryptosporidium spp. isolated from one dog and one cat were both found to be C. parvum. One dog isolate harboured a mixed infection of C. parvum and Giardia Assemblage A. These findings support the growing evidence that household animals are potential reservoirs of the zoonotic pathogens Giardia spp. and Cryptosporidium spp. for infections in humans.

  15. Chronic fatigue syndrome after Giardia enteritis: clinical characteristics, disability and long-term sickness absence

    Directory of Open Access Journals (Sweden)

    Naess Halvor

    2012-02-01

    Full Text Available Abstract Background A waterborne outbreak of Giardia lamblia gastroenteritis led to a high prevalance of long-lasting fatigue and abdominal symptoms. The aim was to describe the clinical characteristics, disability and employmentloss in a case series of patients with Chronic Fatigue Syndrome (CFS after the infection. Methods Patients who reported persistent fatigue, lowered functional capacity and sickness leave or delayed education after a large community outbreak of giardiasis enteritis in the city of Bergen, Norway were evaluated with the established Centers for Disease Control and Prevention criteria for CFS. Fatigue was self-rated by the Fatigue Severity Scale (FSS. Physical and mental health status and functional impairment was measured by the Medical Outcome Severity Scale-short Form-36 (SF-36. The Hospital Anxiety and Depression Scale (HADS was used to measure co-morbid anxiety and depression. Inability to work or study because of fatigue was determined by sickness absence certified by a doctor. Results A total of 58 (60% out of 96 patients with long-lasting post-infectious fatigue after laboratory confirmed giardiasis were diagnosed with CFS. In all, 1262 patients had laboratory confirmed giardiasis. At the time of referral (mean illness duration 2.7 years 16% reported improvement, 28% reported no change, and 57% reported progressive course with gradual worsening. Mean FSS score was 6.6. A distinctive pattern of impairment was documented with the SF-36. The physical functioning, vitality (energy/fatigue and social functioning were especially reduced. Long-term sickness absence from studies and work was noted in all patients. Conclusion After giardiasis enteritis at least 5% developed clinical characteristics and functional impairment comparable to previously described post-infectious fatigue syndrome.

  16. Identification of zoonotic genotypes of Giardia duodenalis.

    Directory of Open Access Journals (Sweden)

    Hein Sprong

    Full Text Available Giardia duodenalis, originally regarded as a commensal organism, is the etiologic agent of giardiasis, a gastrointestinal disease of humans and animals. Giardiasis causes major public and veterinary health concerns worldwide. Transmission is either direct, through the faecal-oral route, or indirect, through ingestion of contaminated water or food. Genetic characterization of G. duodenalis isolates has revealed the existence of seven groups (assemblages A to G which differ in their host distribution. Assemblages A and B are found in humans and in many other mammals, but the role of animals in the epidemiology of human infection is still unclear, despite the fact that the zoonotic potential of Giardia was recognised by the WHO some 30 years ago. Here, we performed an extensive genetic characterization of 978 human and 1440 animal isolates, which together comprise 3886 sequences from 4 genetic loci. The data were assembled into a molecular epidemiological database developed by a European network of public and veterinary health Institutions. Genotyping was performed at different levels of resolution (single and multiple loci on the same dataset. The zoonotic potential of both assemblages A and B is evident when studied at the level of assemblages, sub-assemblages, and even at each single locus. However, when genotypes are defined using a multi-locus sequence typing scheme, only 2 multi-locus genotypes (MLG of assemblage A and none of assemblage B appear to have a zoonotic potential. Surprisingly, mixtures of genotypes in individual isolates were repeatedly observed. Possible explanations are the uptake of genetically different Giardia cysts by a host, or subsequent infection of an already infected host, likely without overt symptoms, with a different Giardia species, which may cause disease. Other explanations for mixed genotypes, particularly for assemblage B, are substantial allelic sequence heterogeneity and/or genetic recombination. Although the

  17. Axenic isolation of viable Giardia muris trophozoites.

    Science.gov (United States)

    Tillotson, K D; Buret, A; Olson, M E

    1991-06-01

    Large numbers of viable Giardia muris trophozoites were isolated from the duodenum of experimentally infected mice 6 days after inoculation with 1,000 G. muris cysts. A series of shaking, incubation, and washing steps in the presence of the broad-spectrum antibiotic piperacillin readily provided 4.9 +/- 1.5 x 10(5) G. muris trophozoites per mouse, free of detectable contaminant organisms. Anaerobic and microaerophilic culturing and scanning electron microscopy demonstrated axenic status and high purity of the isolates. The viability of trophozoites was 98 +/- 2%. Application of this technique should permit novel immunological and epidemiological analyses of G. muris infection and biochemical investigations of this protozoan parasite.

  18. Cryptosporidium and Giardia removal by secondary and tertiary wastewater treatment.

    Science.gov (United States)

    Taran-Benshoshan, Marina; Ofer, Naomi; Dalit, Vaizel-Ohayon; Aharoni, Avi; Revhun, Menahem; Nitzan, Yeshayahu; Nasser, Abidelfatah M

    2015-01-01

    Wastewater disposal may be a source of environmental contamination by Cryptosporidium and Giardia. This study was conducted to evaluate the prevalence of Cryptosporidium oocysts and Giardia cysts in raw and treated wastewater effluents. A prevalence of 100% was demonstrated for Giardia cysts in raw wastewater, at a concentration range of 10 to 12,225 cysts L(-1), whereas the concentration of Cryptosporidium oocysts in raw wastewater was 4 to 125 oocysts L(-1). The removal of Giardia cysts by secondary and tertiary treatment processes was greater than those observed for Cryptosporidium oocysts and turbidity. Cryptosporidium and Giardia were present in 68.5% and 76% of the tertiary effluent samples, respectively, at an average concentration of 0.93 cysts L(-1) and 9.94 oocysts L(-1). A higher detection limit of Cryptosporidium oocysts in wastewater was observed for nested PCR as compared to immune fluorescent assay (IFA). C. hominis was found to be the dominant genotype in wastewater effluents followed by C. parvum and C. andersoni or C. muris. Giardia was more prevalent than Cryptosporidium in the studied community and treatment processes were more efficient for the removal of Giardia than Cryptosporidium. Zoonotic genotypes of Cryptosporidium were also present in the human community. To assess the public health significance of Cryptosporidium oocysts present in tertiary effluent, viability (infectivity) needs to be assessed.

  19. Comparison of the levels of intra-specific genetic variation within Giardia muris and Giardia intestinalis.

    Science.gov (United States)

    Andrews, R H; Monis, P T; Ey, P L; Mayrhofer, G

    1998-08-01

    The extent of intra-specific genetic variation between isolates of Giardia muris was assessed by allozyme electrophoresis. Additionally, the levels of allozymic variation detected within G. muris were compared with those observed between members of the two major assemblages of the morphologically distinct species Giardia intestinalis. Four isolates of G. muris were analysed. Three (Ad-120, -150, -151) were isolated from mice in Australia, while the fourth (R-T) was isolated from a golden hamster in North America. The 11 isolates of G. intestinalis (Ad-1, -12, -2, -62, representing genetic Groups I and II of Assemblage A and BAH-12, BRIS/87/HEPU/694, Ad-19, -22, -28, -45, -52, representing genetic Groups III and IV of Assemblage B) were from humans in Australia. Intra-specific genetic variation was detected between G. muris isolates at four of the 23 enzyme loci examined. Similar levels of variation were found within the genetic groups that comprise Assemblages A and B of G. intestinalis. These levels of intra-specific variation are similar to those observed within other morphologically-distinct species of protozoan parasites. We suggest that the magnitude of the genetic differences detected within G. muris provides an indication of the range of genetic variation within other species of Giardia and that this can be used as a model to delineate morphologically similar but genetically distinct (cryptic) species within this genus.

  20. Intravascular detection of Giardia trophozoites in naturally infected mice

    Directory of Open Access Journals (Sweden)

    El-Shewy K.A.

    2003-06-01

    Full Text Available During routine transmission electron microscopic (TEM examination of mice naturally infected with Giardia muris, an intense infection with Giardia trophozoites was demonstrated within intestinal and renal tissues. Examination of randomly taken sections from these heavily infected tissues revealed marked deep affection with mixed pathology. Duodenal sections were found loaded with Giardia trophozoites in intimate contact with necrotic gut cells. Some of these trophozoites were detected within central lacteal of damaged villi and nearby blood vessels. Interestingly, and for the first time to be demonstrated, morphologically identical G. muris trophozoite was detected in a renal blood vessel. An intense cellular immune reaction was obviously demonstrated with remarkable interaction between giant macrophages and the trophozoites particulates. Involvement of deep tissues by Giardia trophozoites and their presence within vascular channels could open up questions about the possible invasive and disseminative behavior of G. muris, particularly in heavily and naturally infected hosts.

  1. Molecular characterization of Giardia psittaci by multilocus sequence analysis.

    Science.gov (United States)

    Abe, Niichiro; Makino, Ikuko; Kojima, Atsushi

    2012-12-01

    Multilocus sequence analyses targeting small subunit ribosomal DNA (SSU rDNA), elongation factor 1 alpha (ef1α), glutamate dehydrogenase (gdh), and beta giardin (β-giardin) were performed on Giardia psittaci isolates from three Budgerigars (Melopsittacus undulates) and four Barred parakeets (Bolborhynchus lineola) kept in individual households or imported from overseas. Nucleotide differences and phylogenetic analyses at four loci indicate the distinction of G. psittaci from the other known Giardia species: Giardia muris, Giardia microti, Giardia ardeae, and Giardia duodenalis assemblages. Furthermore, G. psittaci was related more closely to G. duodenalis than to the other known Giardia species, except for G. microti. Conflicting signals regarded as "double peaks" were found at the same nucleotide positions of the ef1α in all isolates. However, the sequences of the other three loci, including gdh and β-giardin, which are known to be highly variable, from all isolates were also mutually identical at every locus. They showed no double peaks. These results suggest that double peaks found in the ef1α sequences are caused not by mixed infection with genetically different G. psittaci isolates but by allelic sequence heterogeneity (ASH), which is observed in diplomonad lineages including G. duodenalis. No sequence difference was found in any G. psittaci isolates at the gdh and β-giardin, suggesting that G. psittaci is indeed not more diverse genetically than other Giardia species. This report is the first to provide evidence related to the genetic characteristics of G. psittaci obtained using multilocus sequence analysis. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. High-resolution electron microscopic evidence for the filamentous structure of the cyst wall in Giardia muris and Giardia duodenalis.

    Science.gov (United States)

    Erlandsen, S L; Bemrick, W J; Pawley, J

    1989-10-01

    High-resolution morphological studies of the cyst wall of Giardia spp. were performed using low-voltage scanning electron microscopy (LVSEM) and transmission electron microscopy (TEM). The cyst wall was composed of membranous and filamentous layers. The membranous layer consisted of an inner and an outer cyst membrane separated by a thin layer of cytoplasm. The filamentous layer contained individual filaments that ranged from 7 to 20 nm in diameter when measured by LVSEM, formed a dense meshwork with branches or interconnections, and were occasionally arranged on the surface in whorled patterns. Cysts of Giardia muris from mice, Giardia duodenalis from dogs, pigs, voles, beavers, muskrats, and humans, and Giardia psittaci from a bird (parakeet), possessed an essentially identical wall composed of filaments. Inducement of excystation in viable Giardia cysts produced a dramatic increase in the interfilament spacing over an entire cyst, but none was observed in heat-killed or chemically fixed control cysts. These results demonstrated that the cyst wall of Giardia spp. was composed of a complex arrangement of filaments, presumably formed during the process of encystment.

  3. STRUCTURAL INSIGHTS INTO SUBSTRATE BINDING AND STEREOSELECTIVITY OF GIARDIA FRUCTOSE-1,6-BISPHOSPHATE ALDOLASE*

    Science.gov (United States)

    Galkin, Andrey; Li, Zhimin; Li, Ling; Kulakova, Liudmila; Pal, Lipika R.; Dunaway-Mariano, Debra; Herzberg, Osnat

    2009-01-01

    Giardia lamblia fructose-1,6-bisphosphate aldolase (FBPA)1 is a member of the Class II zinc-dependent aldolase family that catalyzes the cleavage of D-fructose-1,6-bisphosphate (FBP) into dihydroxyacetone phosphate (DHAP) and D-glyceraldehyde-3-phosphate (G3P). In addition to the active site zinc, the catalytic apparatus of FBPA employs an aspartic acid, Asp83 in the G. lamblia enzyme, which when replaced by an alanine residue renders the enzyme inactive. A comparison of the crystal structures of the D83A FBPA in complex with FBP and of the wild-type FBPA in the unbound state revealed a substrate induced conformational transition of loops in the vicinity of the active site and a shift in the location of Zn2+. Upon FBP binding, the Zn2+ shifts up to 4.6 Å towards the catalytic Asp83, which brings the metal within coordination distance to the Asp83 carboxylate group. In addition, the structure of wild-type FBPA was determined in complex with the competitive inhibitor D-tagatose 1,6-bisphosphate (TBP), a FBP stereoisomer. In this structure, the zinc binds in a site close to that previously seen in the structure of FBPA in complex with phosphoglycolohydroxamate, an analog of the postulated DHAP ene-diolate intermediate. Together, the ensemble of structures suggests that the zinc mobility is necessary to orient the Asp83 side chain and to polarize the substrate for proton transfer from the FBP C(4) hydroxyl group to the Asp83 carboxyl group. In the absence of FBP, the alternative zinc position is too remote for coordinating the Asp83. We propose a modification of the catalytic mechanism that incorporates the novel features observed in the FBPA/FBP structure. The mechanism invokes coordination and co-planarity of the Zn2+ with the FBP’s O-C(3)-C(4)-O concomitant with coordination of Asp83 carboxylic group. Catalysis is accompanied by movement of Zn2+ to a site co-planar with the O-C(2)-C(3)-O of the DHAP. glFBPA exhibit strict substrate specificity towards FBP and

  4. Giardia and Cryptosporidium species and genotypes in coyotes (Canis latrans).

    Science.gov (United States)

    Trout, James M; Santín, Mónica; Fayer, Ronald

    2006-06-01

    Feces and duodenal scrapings were collected from 22 coyotes (Canis latrans) killed in managed hunts in northeastern Pennsylvania. Polymerase chain reaction (PCR) methods were used to detect Giardia and Cryptosporidium spp. PCR-amplified fragments of Giardia and Cryptosporidium spp. SSU-rRNA genes were subjected to DNA sequence analysis for species/genotype determination. Seven coyotes (32%) were positive for G. duodenalis: three assemblage C, three assemblage D, and one assemblage B. Six coyotes (27%) were positive for Cryptosporidium spp. One isolate shared 99.7% homology with C. muris, whereas five others (23%) shared 100% homology with C. canis, coyote genotype. This is the first report on multiple genotypes of Giardia spp. in coyotes and on the prevalence of Cryptosporidium spp. genotypes in coyotes.

  5. Interleukin-17 receptor A (IL-17RA) as a central regulator of the protective immune response against Giardia.

    Science.gov (United States)

    Paerewijck, Oonagh; Maertens, Brecht; Dreesen, Leentje; Van Meulder, Frederik; Peelaers, Iris; Ratman, Dariusz; Li, Robert W; Lubberts, Erik; De Bosscher, Karolien; Geldhof, Peter

    2017-08-17

    The protozoan parasite Giardia is a highly prevalent intestinal pathogen with a wide host range. Data obtained in mice, cattle and humans revealed the importance of IL-17A in the development of a protective immune response against Giardia. The aim of this study was to further unravel the protective effector mechanisms triggered by IL-17A following G. muris infection in mice, by an RNA-sequencing approach. C57BL/6 WT and C57BL/6 IL-17RA KO mice were orally infected with G. muris cysts. Three weeks post infection, intestinal tissue samples were collected for RNA-sequencing, with samples from uninfected C57BL/6 WT and C57BL/6 IL-17RA KO animals serving as negative controls. Differential expression analysis showed that G. muris infection evoked the transcriptional upregulation of a wide array of genes, mainly in animals with competent IL-17RA signaling. IL-17RA signaling induced the production of various antimicrobial peptides, such as angiogenin 4 and α- and β-defensins and regulated complement activation through mannose-binding lectin 2. The expression of the receptor that regulates the secretion of IgA into the intestinal lumen, the polymeric immunoglobulin receptor, was also dependent on IL-17RA signaling. Interestingly, the transcriptome data showed for the first time the involvement of the circadian clock in the host response following Giardia infection.

  6. Prevalence of Giardia intestinalis and Hymenolepis nana in Afghan ...

    African Journals Online (AJOL)

    Background: Present study aimed to investigate prevalence of Giardia intestinalis and Hymenolepis nana in Afghan refugees visiting Central Health Unit (CHU), Kot ... are common among Afghan refugees and serious preventive measures should be implemented to promote the safety and healthy lifestyle of these people.

  7. Effect of Piper betle on Giardia intestinalis infection in vivo

    Czech Academy of Sciences Publication Activity Database

    Pecková, R.; Doležal, Karel; Sak, Bohumil; Květoňová, Dana; Kváč, Martin; Nurcahyo, W.; Foitová, I.

    2018-01-01

    Roč. 184, JAN (2018), s. 39-45 ISSN 0014-4894 R&D Projects: GA ČR(CZ) GAP505/11/1163 Institutional support: RVO:61389030 ; RVO:60077344 Keywords : Antigiardial activity * Drug of choice * Giardia intestinalis * Natural antiparasitics * Parasites * Piper betle Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany Impact factor: 1.724, year: 2016

  8. Cryptosporidium and Giardia: new challenges to the water industry

    NARCIS (Netherlands)

    Medema, Gerriet Jan

    1999-01-01

    The protozoan parasites Cryptosporidium parvum and Giardia intestinalis have emerged as significant waterborne pathogens over the past decades. Many outbreaks of waterborne cryptosporidiosis and giardiasis have been recorded,primarily in the United States and the United Kingdom.Chapter 1 gives an

  9. Eliminatie van virussen, Cryptosporidium en Giardia door drinkwaterzuiveringsprocessen

    NARCIS (Netherlands)

    Medema GJ; Theunissen J; MGB

    1996-01-01

    A study on the removal efficiency of drinking water treatment processes for viruses and protozoa (Cryptosporidium/Giardia). The description is based on the best available Dutch and, if data on the Dutch situation are absent, international research data. The approach is valid for well-designed and

  10. LOW PRESSURE ULTRAVIOLET STUDIES FOR INACTIVIATION OF GIARDIA MURIS CYSTS

    Science.gov (United States)

    This research was initiated to confirm and expand the current database for the inactiviation of Giardia spp. using ultraviolet (UV) radiation. The path taken was to confirm earlier UV research that used excystation as the indication of viability. In this study, an in vitro excyst...

  11. LOW PRESSURE ULTRAVIOLET STUDIES FOR INACTIVATION OF GIARDIA MURIS CYSTS

    Science.gov (United States)

    This research was initiated to confirm and expand the current database for the inactivation of Giardia spp. using ultraviolet (UV) radiation. Initially, previous research that used in vitro excystation as the indicator for UV effectiveness was confirmed. Later, the in vitro excys...

  12. LOW PRESSURE ULTRAVEIOLET STUDIES FOR INACTIVATION OF GIARDIA MURIS CYSTS

    Science.gov (United States)

    Cysts of Giardia muris were inactivated using a low pressure ultravolet (UV) light source. Cyst viability was detemined by both in vitro excystation and animal infectivity. Cyst doeses were counted using a flow cytometer for the animal infectivity experiments. Using in vitro excy...

  13. First record of Giardia in cattle in Denmark

    DEFF Research Database (Denmark)

    Iburg, T.; Gasser, R.B.; Henriksen, S.A.

    1996-01-01

    Faecal samples from asymptomatic dairy cows and calves from a farm on the Island Falster, Denmark, were examined by a sucrose gradient flotation technique. Giardia cysts were found in 7.6% of the 92 samples, and estimated cyst excretion rates ranged from 50-200 cysts per gram faeces. Given that G...

  14. The Superoxide Reductase from the Early Diverging Eukaryote Giardia Intestinalis

    International Nuclear Information System (INIS)

    Cabelli, D.E.; Testa, F.; Mastronicola, D.; Bordi, E.; Pucillo, L.P.; Sarti, P.; Saraiva, L.M.; Giuffre, A.; Teixeira, M.

    2011-01-01

    Unlike superoxide dismutases (SODs), superoxidereductases (SORs) eliminate superoxide anion (O 2 # sm b ullet# - ) not through its dismutation, but via reduction to hydrogen peroxide (H 2 O 2 ) in the presence of an electron donor. The microaerobic protist Giardia intestinalis, responsible for a common intestinal disease in humans, though lacking SOD and other canonical reactive oxygen species-detoxifying systems, is among the very few eukaryotes encoding a SOR yet identified. In this study, the recombinant SOR from Giardia (SOR Gi ) was purified and characterized by pulse radiolysis and stopped-flow spectrophotometry. The protein, isolated in the reduced state, after oxidation by superoxide or hexachloroiridate(IV), yields a resting species (T final ) with Fe 3+ ligated to glutamate or hydroxide depending on pH (apparent pK a = 8.7). Although showing negligible SOD activity, reduced SOR Gi reacts with O 2 # sm b ullet# - with a pH-independent second-order rate constant k 1 = 1.0 x 10 9 M -1 s -1 and yields the ferric-(hydro)peroxo intermediate T 1 ; this in turn rapidly decays to the T final state with pH-dependent rates, without populating other detectable intermediates. Immunoblotting assays show that SOR Gi is expressed in the disease-causing trophozoite of Giardia. We propose that the superoxide-scavenging activity of SOR in Giardia may promote the survival of this air-sensitive parasite in the fairly aerobic proximal human small intestine during infection.

  15. Molecular characterization of Giardia intestinalis assemblage E from goat kids in Bangladesh

    OpenAIRE

    Mohammad Alamgir Hossain; Sohana Akter Mina; Lolo Wal Marzan; Mohammad Asif Imran Khan Emon; Rasel Das; AMAM Zonaed Siddiki

    2015-01-01

    Objective: To molecularly characterize Giardia in goat kids to elucidate the possible zoonotic hazards in Bangladesh and find out the role of Giardia protozoan parasite as a source of human infection. Methods: Fecal samples of 100 goat kids were genotyped by nested PCR amplification of β-giardin gene fragment followed by sequencing and analysis. Results: The total prevalence of Giardia in goat kids was 3% (3/100) and the infection is more widespread in younger (P = 0.36), Bl...

  16. Giardia assemblage A: human genotype in muskoxen in the Canadian Arctic

    Directory of Open Access Journals (Sweden)

    Nagy John

    2008-09-01

    Full Text Available Abstract As part of an ongoing program assessing the biodiversity and impacts of parasites in Arctic ungulates we examined 72 fecal samples from muskoxen on Banks Island, Northwest Territories, Canada for Giardia and Cryptosporidium. Cryptosporidium spp. were not detected, but 21% of the samples were positive for Giardia. Sequencing of four isolates of Giardia demonstrated G. duodenalis, Assemblage A, a zoonotic genotype.

  17. Cryptosporidium and Giardia in Swimming Pools, Atlanta, Georgia

    Centers for Disease Control (CDC) Podcasts

    In this podcast, Dan Rutz speaks with Dr. Joan Shields, a guest researcher with the Healthy Swimming Program at CDC, about an article in June 2008 issue of Emerging Infectious Diseases reporting on the results of a test of swimming pools in the greater Atlanta, Georgia area. Dr. Shields tested 160 pools in metro Atlanta last year for Cryptosporidium and Giardia. These germs cause most recreational water associated outbreaks.

  18. Purification of Giardia muris cysts by velocity sedimentation.

    OpenAIRE

    Sauch, J F

    1984-01-01

    Giardia muris cysts were separated from fecal contaminants in primary isolates by unit gravity velocity sedimentation. Crude isolates obtained by centrifugation over 1.0 M sucrose were overlaid onto a Percoll density gradient, 1.01 to 1.03 g/ml. G. muris cysts were well separated from faster-sedimenting fecal debris and slower-sedimenting Spironucleus muris and bacteria in 1.5 h.

  19. Purification of Giardia muris cysts by velocity sedimentation.

    Science.gov (United States)

    Sauch, J F

    1984-01-01

    Giardia muris cysts were separated from fecal contaminants in primary isolates by unit gravity velocity sedimentation. Crude isolates obtained by centrifugation over 1.0 M sucrose were overlaid onto a Percoll density gradient, 1.01 to 1.03 g/ml. G. muris cysts were well separated from faster-sedimenting fecal debris and slower-sedimenting Spironucleus muris and bacteria in 1.5 h. PMID:6486790

  20. Giardia in a selected population of dogs and cats in Germany - diagnostics, coinfections and assemblages.

    Science.gov (United States)

    Sommer, M F; Rupp, P; Pietsch, M; Kaspar, A; Beelitz, P

    2018-01-15

    Infections with the zoonotic endoparasite Giardia duodenalis are widely spread among dogs and cats worldwide. Since the question whether the infection might be transmitted from domestic animals to their owners is still an important topic, a reliable detection of patent Giardia infections and the determination of the associated Giardia assemblages is of major concern. The objectives of the present study were to determine the prevalence of Giardia infections in dogs and cats living in Germany using different diagnostic tests and to identify the Giardia assemblages of infected animals. Furthermore, a possible correlation of coinfections with other endoparasites was analysed. All samples were investigated by enzyme-linked immunosorbent assay (ELISA), merthiolate-iodine-formalin concentration technique (MIFC) and zinc chloride flotation. ELISA-positive samples were additionally screened with a direct immunofluorescence assay (IFA). Faecal DNA was extracted from all Giardia cyst-positive samples and used for multilocus sequence typing with nested PCRs targeting the following gene loci: SSU rRNA (SSU), glutamate dehydrogenase (gdh) and triosephosphate isomerase (tpi). Samples from dogs and cats tested positive for Giardia coproantigen (ELISA) in 30.6% and 17.9%, respectively. The MIFC technique revealed Giardia cysts in 33.9% of canine and in 34.6% of feline ELISA-positive samples, while using IFA, cysts were present in 90.4% of canine and in 76.9% of feline ELISA-positive samples. Coinfections with other endoparasites besides Giardia were found in both dogs and cats, yet a statistically significant correlation could solely be drawn for the canine samples. The success rate of the different PCR protocols varied between 23.1% (tpi) and 91.3% (SSU) for dogs and between 25.0% (gdh) and 90.0% (SSU) for cats. Dog-specific Giardia assemblages C and D were detected in 42 and 55 canine isolates, respectively. The cat-specific Giardia assemblage F was detected in 14 feline isolates

  1. DETECTION OF GIARDIA IN ENVIRONMENTAL WATERS BY IMMUNO-PCR AMPLIFICATION METHODS

    Science.gov (United States)

    Genomic DNA was extracted either directly from Giardia muris cysts seeded into environmental surface waters or from cysts isolated by immunomagnetic beads (IMB}. A 0.171-kbp segment of the giardin gene was PCR-amplified following "direct extraction" of Giardia DNA from seeded Cah...

  2. Studies on the prevalence of giardia cysts and cryptosporidium oocysts in South-African water

    CSIR Research Space (South Africa)

    Kfir, R

    1995-01-01

    Full Text Available per sample and the number of positive samples. Almost 50% of sewage samples studied contained Giardia cysts and 30% contained both Giardia cysts and Cryptosporium oocysts. Treatment of sewage resulted in a reduction in the percentage of samples...

  3. First record of Giardia assemblage D infection in farmed raccoon dogs (Nyctereutes procyonoides

    Directory of Open Access Journals (Sweden)

    Piotr Solarczyk

    2016-09-01

    Full Text Available The presence of Giardia genotypes was investigated in 18 raccoon dogs ( Nyctereutes procyonoides and 80 red foxes ( Vulpes vulpes on one farm. To demonstrate Giardia cysts, fresh and trichrome stained smears were microscopically screened. Two molecular markers were used for Giardia genotyping: a fragment of the beta-giardin gene and a fragment of the glutamate dehydrogenase gene. All faecal samples obtained from red foxes were negative. Giardia cysts were identified only in 2 of the 18 raccoon dogs. The result of genotyping and phylogenetic analysis showed that the G. duodenalis from both raccoon dogs belonged to the D assemblage. This finding of a new animal reservoir of G. duodenalis canids-specific genotypes is important in order to eliminate the risk of infecting other animals bred for fur. Further molecular analyses of Giardia isolates in raccoon dogs are required. The present study represents the first contribution to knowledge of G. duodenalis genotypes in raccoon dogs.

  4. Occurrence of Cryptosporidium oocysts and Giardia cysts in water supplies of San Pedro Sula, Honduras

    Directory of Open Access Journals (Sweden)

    Solo-Gabriele Helena María

    1998-01-01

    Full Text Available During June 1996, water supplies of the city of San Pedro Sula, Honduras, were sampled to obtain an assessment of Cryptosporidium oocyst and Giardia cyst concentrations. Each sample was concentrated and stained with an indirect immunofluorescent antibody, and parasites were counted through microscopic analysis. In three surface water supplies, Cryptosporidium oocyst concentrations ranged from 58 to 260 oocysts per 100 L, and Giardia cysts were present in concentrations ranging from 380 to 2100 cysts per 100 L. Unlike the surface water samples, groundwater had a higher concentration of Cryptosporidium oocysts (26/100 L than Giardia cysts (6/100 L, suggesting that the groundwater aquifer protects the water supply more effectively from larger Giardia cysts. Cryptosporidium oocyst concentrations are within the typical range for surface water supplies in North America whereas Giardia cyst concentrations are elevated. Efforts should be made to protect raw water from sources of contamination.

  5. Molecular systematics of the parasitic protozoan Giardia intestinalis.

    Science.gov (United States)

    Monis, P T; Andrews, R H; Mayrhofer, G; Ey, P L

    1999-09-01

    The long-standing controversy regarding whether Giardia intestinalis is a single species prevalent in both human and animal hosts or a species complex consisting of morphologically similar organisms that differ in host range and other biotypic characteristics is an issue with important medical, veterinary, and environmental management implications. In the past decade, highly distinct genotypes (some apparently confined to particular host groups) have been identified by genetic analysis of samples isolated from different host species. The aim of this study was to undertake a phylogenetic analysis of G. intestinalis that were representative of all known major genetic groups and compare them with other Giardia species, viz. G. ardeae, G. muris, and G. microti. Segments from four "housekeeping" genes (specifying glutamate dehydrogenase, triose phosphate isomerase, elongation factor 1 alpha, and 18S ribosomal RNA) were examined by analysis of 0.48-0.69-kb nucleotide sequences determined from DNA amplified in polymerase chain reactions from each locus. In addition, isolates were compared by allozymic analysis of electrophoretic data obtained for 21 enzymes representing 23 gene loci. The results obtained from these independent techniques and different loci were essentially congruous. Analyses using G. ardeae and/or G. muris as outgroups supported the monophyly of G. intestinalis and also showed that this species includes genotypes that represent at least seven deeply rooted lineages, herein designated assemblages A-G. Inclusion of G. microti in the analysis of 18S rRNA sequence data demonstrated the monophyly of Giardia with the same median body morphology but did not support the monophyly of G. intestinalis, instead placing G. microti within G. intestinalis. The findings support the hypothesis that G. intestinalis is a species complex and suggest that G. microti is a member of this complex.

  6. Monitoring of Cryptosporidium and Giardia in Czech drinking water sources.

    Science.gov (United States)

    Dolejs, P; Ditrich, O; Machula, T; Kalousková, N; Puzová, G

    2000-01-01

    In Czech raw water sources for drinking water supply, Cryptosporidium was found in numbers from 0 to 7400 per 100 liters and Giardia from 0 to 485 per 100 liters. The summer floods of 1997 probably brought the highest numbers of Cryptosporidium oocysts into one of the reservoirs sampled; since then these numbers decreased steadily. A relatively high number of Cryptosporidium oocysts was found in one sample of treated water. Repeated sampling demonstrated that this was a sporadic event. The reason for the presence of Cryptosporidium in a sample of treated drinking-water is unclear and requires further study.

  7. Cryptosporidium and Giardia in Swimming Pools, Atlanta, Georgia

    Centers for Disease Control (CDC) Podcasts

    2008-05-29

    In this podcast, Dan Rutz speaks with Dr. Joan Shields, a guest researcher with the Healthy Swimming Program at CDC, about an article in June 2008 issue of Emerging Infectious Diseases reporting on the results of a test of swimming pools in the greater Atlanta, Georgia area. Dr. Shields tested 160 pools in metro Atlanta last year for Cryptosporidium and Giardia. These germs cause most recreational water associated outbreaks.  Created: 5/29/2008 by Emerging Infectious Diseases.   Date Released: 5/29/2008.

  8. Performance of microscopy and ELISA for diagnosing Giardia duodenalis infection in different pediatric groups.

    Science.gov (United States)

    Silva, Renata K N R; Pacheco, Flávia T F; Martins, Adson S; Menezes, Joelma F; Costa-Ribeiro, Hugo; Ribeiro, Tereza C M; Mattos, Ângela P; Oliveira, Ricardo R; Soares, Neci M; Teixeira, Márcia C A

    2016-12-01

    Techniques for Giardia diagnosis based on microscopy are usually applied as routine laboratory testing; however, they typically exhibit low sensitivity. This study aimed to evaluate Giardia duodenalis and other intestinal parasitic infections in different pediatric groups, with an emphasis on the comparison of Giardia diagnostic techniques. Feces from 824 children from different groups (diarrheic, malnourished, with cancer and from day care) were examined by microscopy and ELISA for Giardia, Cryptosporidium sp. and Entamoeba histolytica coproantigen detection. Giardia-positive samples from day-care children, identified by either microscopy or ELISA, were further tested by PCR targeting of the β-giardin and Gdh genes. Statistically significant differences (Psp. in diarrheic and malnourished groups; infections by Entamoeba histolytica were found only in children with diarrhea. Considering positivity for Giardia by at least one method, ELISA was found to be more sensitive than microscopy (97% versus 55%). To examine discrepancies among the diagnostic methods, 71 Giardia-positive stool samples from day-care children were tested by PCR; of these, DNA was amplified from 51 samples (77.4%). Concordance of positivity between microscopy and ELISA was found for 48 samples, with 43 confirmed by PCR. Parasite DNA was amplified from eleven of the 20 Giardia samples (55%) identified only by ELISA. This study shows the higher sensitivity of ELISA over microscopy for Giardia diagnosis when a single sample is analyzed and emphasizes the need for methods based on coproantigen detection to identify this parasite in diarrheic fecal samples. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  9. Giardia-specific cellular immune responses in post-giardiasis chronic fatigue syndrome.

    Science.gov (United States)

    Hanevik, Kurt; Kristoffersen, Einar; Mørch, Kristine; Rye, Kristin Paulsen; Sørnes, Steinar; Svärd, Staffan; Bruserud, Øystein; Langeland, Nina

    2017-01-28

    The role of pathogen specific cellular immune responses against the eliciting pathogen in development of post-infectious chronic fatigue syndrome (PI-CFS) is not known and such studies are difficult to perform. The aim of this study was to evaluate specific anti-Giardia cellular immunity in cases that developed CFS after Giardia infection compared to cases that recovered well. Patients reporting chronic fatigue in a questionnaire study three years after a Giardia outbreak were clinically evaluated five years after the outbreak and grouped according to Fukuda criteria for CFS and idiopathic chronic fatigue. Giardia specific immune responses were evaluated in 39 of these patients by proliferation assay, T cell activation and cytokine release analysis. 20 Giardia exposed non-fatigued individuals and 10 healthy unexposed individuals were recruited as controls. Patients were clinically classified into CFS (n = 15), idiopathic chronic fatigue (n = 5), fatigue from other causes (n = 9) and recovered from fatigue (n = 10). There were statistically significant antigen specific differences between these Giardia exposed groups and unexposed controls. However, we did not find differences between the Giardia exposed fatigue classification groups with regard to CD4 T cell activation, proliferation or cytokine levels in 6 days cultured PBMCs. Interestingly, sCD40L was increased in patients with PI-CFS and other persons with fatigue after Giardia infection compared to the non-fatigued group, and correlated well with fatigue levels at the time of sampling. Our data show antigen specific cellular immune responses in the groups previously exposed to Giardia and increased sCD40L in fatigued patients.

  10. [Experimental infection of the gerbil (Meriones unguiculatus) by Colombian isolates of Giardia duodenalis].

    Science.gov (United States)

    Arévalo, Adriana; Duque, Sofía; Nicholls, Rubén Santiago

    2005-09-01

    Natural and experimental Giardia infections have been reported from bovines, equines, goats, canines, felines and rodents such as mice, rats and gerbils. The latter have provided successful animal models for Giardia duodenalis and Giardia muris experimental infections. The gerbil model was used to establish the pattern of infection of Colombian Giardia human isolates. Giardia cysts were obtained from stool specimens of symptomatic giardiasis patients by means of sucrose-percoll gradients. Animal inoculation was performed by gastric intubation and injection with 5 x 10(3) Giardia cysts. The course of infection was established by counting cysts every day and trophozoites weekly throughout a period of 30 days. The pattern of cyst excretion was found to be intermittent. Cysts were released during the second and third weeks of infection but not during the first or fourth weeks. The mean minimal number of cysts released per 2-hr collection period was 79 and the mean maximum number was 17,943. Colonization of the small intestine by trophozoites was observed with a mean number ranging from 15,000 to 6,577,778 trophozoites/ml. Gerbils inoculated with G. duodenalis isolates obtained from geographical areas outside Colombia resolved the infection between 86 and 114 days after infection, whereas gerbils infected with Colombian G. duodenalis isolates resolved the infection at 30 days. The gerbil proved to be a good animal model for experimental infection with Colombian isolates of G. duodenalis. Experimental Giardia infection of gerbils permit a sufficient yield of cysts and trophozoites to be used as antigens for the immunization of other animals and to obtain Giardia antibodies that could be used for Giardia antigen detection assays in stool specimens.

  11. Antibody response to Giardia muris trophozoites in mouse intestine.

    Science.gov (United States)

    Heyworth, M F

    1986-05-01

    The protozoan parasite Giardia muris colonizes the mouse small intestinal lumen. This parasite is cleared immunologically from the intestine of normal mice. In contrast, T-lymphocyte-deficient (nude) mice have an impaired immunological response to G. muris and become chronically infected. In the present study, trophozoites were harvested from the intestinal lumen of immunocompetent BALB/c mice and nude mice and examined for surface-bound mouse immunoglobulins by immunofluorescence microscopy. Immunoglobulin A (IgA) and IgG, but not IgM, were detected on trophozoites obtained from BALB/c mice, from day 10 of the infection onwards. Trophozoites from nude mice showed very little evidence of surface-bound mouse immunoglobulin at any time during the 5-week period immediately following infection of these animals with G. muris cysts. Intestinal G. muris infection was cleared by the BALB/c mice but not by the nude animals. The data suggest that parasite-specific IgA and IgG bind to G. muris trophozoites in the intestinal lumen of immunocompetent BALB/c mice. Intestinal antibodies that bind to trophozoite surfaces are likely to play an important part in the clearance of G. muris infection by immunocompetent mice. The inability of nude mice to clear this infection at a normal rate is likely to be due to impairment of Giardia-specific intestinal antibody production.

  12. Performance and Health Risk Assessment of Commercial Off-the-Shelf Individual Water Purifiers

    Science.gov (United States)

    2006-05-26

    G.T., 1983. Effect of Resin Disinfectants-I3 and –I5 on Giardia muris and Giardia lamblia. Applied and Environmental Microbiology, 46(5), 965-969...UV doses. The EPA collected UV inactivation research data conducted over the past 50 years for adenovirus, Giardia lamblia, Giardia muris , and... Giardia cysts. One study showed CTs ranging from 1.7-17.6 mg-min/L necessary for 2-log Giardia muris cyst inactivation (reference 23). The SWTR

  13. Differences in staining intensities affect reported occurrences and concentrations of Giardia spp. in surface drinking water sources.

    Science.gov (United States)

    Alderisio, K A; Villegas, L F; Ware, M W; McDonald, L A; Xiao, L; Villegas, E N

    2017-12-01

    USEPA Method 1623, or its equivalent, is currently used to monitor for protozoan contamination of surface drinking water sources worldwide. At least three approved staining kits used for detecting Cryptosporidium and Giardia are commercially available. This study focuses on understanding the differences among staining kits used for Method 1623. Merifluor and EasyStain labelling kits were used to monitor Cryptosporidium oocyst and Giardia cyst densities in New York City's raw surface water sources. In the year following a change to the approved staining kits for use with Method 1623, an anomaly was noted in the occurrence of Giardia cysts in New York City's raw surface water. Specifically, Merifluor-stained samples had higher Giardia cyst densities as compared with those stained with EasyStain. Side by side comparison revealed significantly lower fluorescence intensities of Giardia muris as compared with Giardia duodenalis cysts when labelled with EasyStain. This study showed very poor fluorescence intensity signals by EasyStain on G. muris cysts resulting in lower cyst counts, while Merifluor, with its broader Giardia cyst staining specificity, resulted in higher cyst counts, when using Methods 1623. These results suggest that detected Giardia cyst concentrations are dependent on the staining kits used, which can result in a more or less conservative estimation of occurrences and densities of zoonotic Giardia cysts by detecting a broader range of Giardia species/Assemblages. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  14. Post-translational glutamylation and tyrosination in tubulin of tritrichomonads and the diplomonad Giardia intestinalis.

    Science.gov (United States)

    Boggild, A K; Sundermann, C A; Estridge, B H

    2002-01-01

    Glutamylated and tyrosinated tubulin were localized in Giardia intestinalis and selected trichomonads of the Tritrichomonadinae subfamily, using specific monoclonal antibodies directed at each of the post-translational modifications. Analysis was carried out using indirect immunofluorescence microscopy. Although trichomonad tubulins remained unlabeled by anti-tyrosine tubulin (TUB-1A2), the presence of the glutamylation motif (GT 335) was confirmed and found to differ in distribution among tritrichomonads. Tritrichomonas muris was most heavily labeled with GT 335, while T. foetus was the least so. Like trichomonads, Giardia was unreactive to anti-tyrosine tubulin; however, the GT 335 antibody produced marked fluorescence in Giardia trophozoites. This study is the first to report immunofluorescent localization of tubulin glutamylation in Giardia and confirms previously reported mass spectrometry data.

  15. Intravascular detection of Giardia trophozoites in naturally infected mice. An electron microscopic study.

    Science.gov (United States)

    el-Shewy, K A; Eid, R A

    2003-06-01

    During routine transmission electron microscopic (TEM) examination of mice naturally infected with Giardia muris, an intense infection with Giardia trophozoites was demonstrated within intestinal and renal tissues. Examination of randomly taken sections from these heavily infected tissues revealed marked deep affection with mixed pathology. Duodenal sections were found loaded with Giardia trophozoites in intimate contact with necrotic gut cells. Some of these trophozoites were detected within central lacteal of damaged villi and nearby blood vessels. Interestingly, and for the first time to be demonstrated, morphologically identical G. muris trophozoite was detected in a renal blood vessel. An intense cellular immune reaction was obviously demonstrated with remarkable interaction between giant macrophages and the trophozoites particulates. Involvement of deep tissues by Giardia trophozoites and their presence within vascular channels could open up questions about the possible invasive and disseminative behavior of G. muris, particularly in heavily and naturally infected hosts.

  16. Characterization of telomeres and telomerase from the single-celled eukaryote Giardia intestinalis

    Czech Academy of Sciences Publication Activity Database

    Uzlíková, M.; Fulnečková, Jana; Weisz, F.; Sýkorová, Eva; Nohýnková, E.; Tůmová, P.

    2017-01-01

    Roč. 211, JAN 2017 (2017), s. 31-38 ISSN 0166-6851 Grant - others:Grantová agentura ČR - GA ČR(CZ) GAP305/12/1248 Institutional support: RVO:68081707 Keywords : trypanosoma-brucei * parasitic protozoa * 2 nuclei * lamblia * evolution * rna * organization Subject RIV: BO - Biophysics Impact factor: 2.536, year: 2016

  17. Serum antibody responses by male and female C57Bl/6 mice infected with Giardia muris.

    Science.gov (United States)

    Daniels, C W; Belosevic, M

    1994-09-01

    We compared the levels of serum antibodies in male and female C57Bl/6 mice during the primary and after challenge infection with Giardia muris. Male mice began passing cysts in their faeces earlier than females, and were shedding cysts for over 60 days, while females stopped shedding cysts by day 20 after infection. In both males and females there were significant increases in parasite-specific IgM 10 and 20 days after infection. No differences in parasite-specific serum IgA were observed until 40 days after infection. Parasite-specific IgG (whole) levels were elevated on days 20 and 40 in females, while males showed no significant increases. In addition, females had a much stronger IgG2b and IgG3 response than males. After challenge with either cysts or soluble parasite protein only the females had significant increases in specific anti-parasite IgG2b. Our data show differential ability of males and females to control the infection with G. muris is paralleled by a difference in the anti-parasite serum IgG response of the mice.

  18. A new species of Giardia Künstler, 1882 (Sarcomastigophora: Hexamitidae) in hamsters.

    Science.gov (United States)

    Lyu, Zhangxia; Shao, Jingru; Xue, Min; Ye, Qingqing; Chen, Bing; Qin, Yan; Wen, Jianfan

    2018-03-20

    Giardia spp. are flagellated protozoan parasites that infect humans and many other vertebrates worldwide. Currently seven species of Giardia are considered valid. Here, we report a new species, Giardia cricetidarum n. sp. in hamsters. Trophozoites of G. cricetidarum n. sp. are pear-shaped with four pairs of flagella and measure on average 14 μm (range 12-18 μm) in length and 10 μm (range 8-12 μm) in width. The trophozoites of the new species are generally larger and stouter than those of most of the other Giardia spp. and exhibit the lowest length/width ratio (c.1.40) of all recognized Giardia species. Cysts of G. cricetidarum n. sp. are ovoid and measure on average 11 μm (range 9-12 μm) in length and 10 μm (range 8-10 μm) in width and are indistinguishable from the cysts of other Giardia species. Molecular phylogenetic analyses based on beta-giardin, small subunit rRNA, and elongation factor-1 alpha loci all demonstrated that G. cricetidarum n. sp. is genetically distinct from all currently accepted Giardia spp. Investigation of the host range indicated that the new species was only found in hamsters (including Phodopus sungorus, P. campbelli and Mesocricetus auratus), while all the other described mammal-parasitizing species (G. muris, G. microti and G. intestinalis) each infect multiple hosts. Cross-transmission studies further demonstrated the apparent host specificity of G. cricetidarum n. sp. as it only infected hamsters. Trophozoites were found in high numbers in hamster intestines (5 × 10 5 - 5 × 10 6 ) and was rarely detected co-infecting with other Giardia spp. in the common hamster, suggesting it has some advantages in parasitizing hamsters. This study has identified a new species of Giardia, which appears to be specific to hamsters, and together with the three other mammal-parasitizing Giardia species with different host ranges, may be able to be used as a model system for the study of evolutionary divergence of host parasitism strategies in

  19. Molecular characterization of Cryptosporidium and Giardia from the Tasmanian devil (Sarcophilus harrisii).

    Science.gov (United States)

    Wait, Liana F; Fox, Samantha; Peck, Sarah; Power, Michelle L

    2017-01-01

    The Tasmanian devil (Sarcophilus harrisii) is a carnivorous marsupial found only in the wild in Tasmania, Australia. Tasmanian devils are classified as endangered and are currently threatened by devil facial tumour disease, a lethal transmissible cancer that has decimated the wild population in Tasmania. To prevent extinction of Tasmanian devils, conservation management was implemented in 2003 under the Save the Tasmanian Devil Program. This study aimed to assess if conservation management was altering the interactions between Tasmanian devils and their parasites. Molecular tools were used to investigate the prevalence and diversity of two protozoan parasites, Cryptosporidium and Giardia, in Tasmanian devils. A comparison of parasite prevalence between wild and captive Tasmanian devils showed that both Cryptosporidium and Giardia were significantly more prevalent in wild devils (p Giardia was identified in 24.1% of wild devils but only 0.82% of captive devils. Molecular analysis identified the presence of novel genotypes of both Cryptosporidium and Giardia. The novel Cryptosporidium genotype was 98.1% similar at the 18S rDNA to Cryptosporidium varanii (syn. C. saurophilum) with additional samples identified as C. fayeri, C. muris, and C. galli. Two novel Giardia genotypes, TD genotype 1 and TD genotype 2, were similar to G. duodenalis from dogs (94.4%) and a Giardia assemblage A isolate from humans (86.9%). Giardia duodenalis BIV, a zoonotic genotype of Giardia, was also identified in a single captive Tasmanian devil. These findings suggest that conservation management may be altering host-parasite interactions in the Tasmanian devil, and the presence of G. duodenalis BIV in a captive devil points to possible human-devil parasite transmission.

  20. Occurrence and distribution of Giardia species in wild rodents in Germany.

    Science.gov (United States)

    Helmy, Yosra A; Spierling, Nastasja G; Schmidt, Sabrina; Rosenfeld, Ulrike M; Reil, Daniela; Imholt, Christian; Jacob, Jens; Ulrich, Rainer G; Aebischer, Toni; Klotz, Christian

    2018-03-27

    Giardiasis is an important gastrointestinal parasitic disease in humans and other mammals caused by the protozoan Giardia duodenalis. This species complex is represented by genetically distinct groups (assemblages A-H) with varying zoonotic potential and host preferences. Wild rodents can harbor potentially zoonotic assemblages A and B, and the rodent-specific assemblage G. Other Giardia spp. found in these animals are Giardia muris and Giardia microti. For the latter, only limited information on genetic typing is available. It has been speculated that wild rodents might represent an important reservoir for parasites causing human giardiasis. The aim of this study was to investigate the occurrence and distribution of Giardia spp. and assemblage types in wild rodents from different study sites in Germany. Screening of 577 wild rodents of the genera Apodemus, Microtus and Myodes, sampled at eleven study sites in Germany, revealed a high overall Giardia prevalence. Giardia species determination at the SSU rDNA gene locus revealed that Apodemus mice, depending on species, were predominantly infected with one of two distinct G. muris sequence types. Giardia microti was the predominant parasite species found in voles of the genera Microtus and Myodes. Only a few animals were positive for potentially zoonotic G. duodenalis. Subtyping at the beta-giardin (bg) and glutamine dehydrogenase (gdh) genes strongly supported the existence of different phylogenetic subgroups of G. microti that are preferentially harbored by distinct host species. The present study highlights the preference of G. muris for Apodemus, and G. microti for Microtus and Myodes hosts and argues for a very low prevalence of zoonotic G. duodenalis assemblages in wild rodents in Germany. It also provides evidence that G. muris and G. microti subdivide into several phylogenetically distinguishable subgroups, each of which appears to be preferentially harbored by species of a particular rodent host genus

  1. Method to enumerate oocysts of cryptosporidium and cysts of Giardia in water

    International Nuclear Information System (INIS)

    Briancesco, R.; Bonadonna, L.

    2000-01-01

    Cryptosporidium and Giardia have been recognized as etiological agents of gastrointestinal illness in humans with severe consequences on children and immunocompromised individuals. Water seems to be vehicle of infection. In last years many efforts have been done to evaluate a method to enumerate oocysts of Cryptosporidium and cysts of Giardia in waters. Throughout filtration and concentration steps, the two procedures proposed allow to enumerate oocysts and cysts belonging to the two genera of protozoa [it

  2. Diagnosis of Giardia infections by PCR-based methods in children of an endemic area

    Directory of Open Access Journals (Sweden)

    EB David

    2011-01-01

    Full Text Available The present study was designed to estimate the prevalence of Giardia infection in preschool- and school-aged children living in an endemic area. Fecal samples from 573 children were processed by zinc sulfate centrifugal flotation, centrifugal sedimentation (using a commercial device for fecal concentration - TF-Test kit® and polymerase chain reaction (PCR-based methods. Of the stool samples assessed, 277 (48.3% were positive for intestinal parasites and/or commensal protozoa. Centrifugal flotation presented the highest diagnostic sensitivity for Giardia infections. The kappa index revealed that both coproparasitological techniques closely agreed on the Giardia diagnosis (86% versus satisfactory (72% and poor (35% concordances for commensal protozoan and helminth infections, respectively. Concerning Giardia molecular diagnosis, from the 71 microscopy-positive samples, specific amplification of gdh and tpi fragments was noted in 68 (95.7% and 64 (90% samples, respectively. Amplification of gdh and tpi genes was observed, respectively, in 95.7% and 90% of microscopy-positive Giardia samples. For 144 microscopy-negative samples, gdh and tpi gene amplification products were obtained from 8.3% and 35.9% samples, respectively. The agreement between these genes was about 40%. The centrifuge-flotation based method was the most suitable means of Giardia diagnosis assessed in the present study by combining accuracy and low cost.

  3. Detection of Giardia duodenalis antigen in human fecal eluates by enzyme-linked immunosorbent assay using polyclonal antibodies

    Directory of Open Access Journals (Sweden)

    Sofía Duque-Beltrán

    2002-12-01

    Full Text Available The present study developed and standardized an enzime-linked immunosorbent assay (ELISA to detect Giardia antigen in feces using rabbit polyclonal antibodies. Giardia cysts were purified from human fecal samples by sucrose and percoll gradients. Gerbils (Meriones unguiculatus were infected to obtain trophozoites. Rabbits were inoculated with either cyst or trophozoite antigens of 14 Colombian Giardia isolates to develop antibodies against the respective stages. The IgG anti-Giardia were purified by sequential caprylic acid and ammonium sulfate precipitation. A portion of these polyclonal antibodies was linked to alkaline phosphatase (conjugate. One hundred and ninety six samples of human feces, from different patients, were tested by parasitologic diagnosis: 69 were positive for Giardia cysts, 56 had no Giardia parasites, and 71 revealed parasites other than Giardia. The optimal concentration of polyclonal antibodies for antigen capture was 40 µg/ml and the optimal conjugate dilution was 1:100. The absorbance cut-off value was 0.24. The parameters of the ELISA test for Giardia antigen detection were: sensitivity, 100% (95% CI: 93.4-100%; specificity, 95% (95% CI: 88.6-97.6%; positive predictive value, 91% (95% CI: 81.4-95.9%; and negative predictive value, 100% (95% CI: 96.1-100%. This ELISA will improve the diagnosis of Giardia infections in Colombia and will be useful in following patients after treatment.

  4. Detection of Giardia intestinalis infections in Polish soldiers deployed to Afghanistan.

    Science.gov (United States)

    Korzeniewski, Krzysztof; Konior, Monika; Augustynowicz, Alina; Lass, Anna; Kowalska, Ewa

    2016-01-01

    Members of the Polish Military Contingent (PMC) have been stationed in Afghanistan since 2002. They typically serve in areas characterised by low standards of sanitation which often leads to the development of food- and waterborne diseases. The aim of the study was to evaluate the prevalence of Giardia intestinalis infections among Polish soldiers deployed to Afghanistan. The research study was conducted as part of a programme for prevention of parasitic diseases of the gastrointestinal tract run by the Polish Armed Forces. The study was carried out in August 2011; it involved 630 asymptomatic Polish soldiers serving in the Forward Operational Base (FOB) Ghazni in eastern Afghanistan. Stool specimens obtained from members of the PMC were first tested in FOB Ghazni (detection of Giardia intestinalis by Rida Quick Giardia immunochromatographic tests and Ridascreen Giardia immunoenzymatic tests - single samples). Next, the same biological material and two other faecal specimens fixed in 10% formalin were transported to the Military Institute of Medicine in Poland, where they were tested for Giardia intestinalis under light microscopy (direct smear, decantation in distilled water). Parasitological tests performed under light microscopy showed that 2.7% (17/630) of the study group were infected with Giardia intestinalis. Some of these results were confirmed by immunochromatographic tests (6/630). In contrast, immunoenzymatic tests (ELISA) demonstrated a significantly higher detection rate reaching 18.1% (114/630). Immunoenzymatic tests confirmed all the positive results given by light microscopy and by immunochromatographic tests. The prevalence rate of Giardia intestinalis infections in Polish soldiers deployed to Afghanistan was found to be high. Microscopic methods exhibit low sensitivity and therefore may result in the underestimation of the true parasite prevalence. Immunoenzymatic tests (ELISA) showing a much higher sensitivity in comparison to light microscopy

  5. Molecular characterisation of Cryptosporidium and Giardia in cats (Felis catus) in Western Australia.

    Science.gov (United States)

    Yang, Rongchang; Ying, Joyce Lau Jie; Monis, Paul; Ryan, Una

    2015-08-01

    Little is known of the prevalence of Cryptosporidium and Giardia in domestic cats in Western Australia and their potential role as zoonotic reservoirs for human infection. In the present study, a total of 345 faecal samples from four different sources were screened for the presence of Cryptosporidium and Giardia by PCR and genotyped by sequence analysis. Oocyst numbers and cyst numbers for Cryptosporidium and Giardia respectively were also determined using quantitative PCR assays. Cryptosporidium and Giardia were detected in 9.9% (95% CI 6.7-13.0) and 10.1% (95% CI 7.0-13.3) of cats in Western Australia respectively. Sequence analysis at the 18S rRNA locus identified five Cryptosporidium species/genotypes; C. felis (n = 8), C. muris (n = 1), C. ryanae (n = 1), Cryptosporidium rat genotype III (n = 5) and a novel genotype most closely related to Cryptosporidium rat genotype III in one isolate. This is the first report of C. ryanae and Cryptosporidium rat genotype III in cats. For Giardia, assemblage F the most commonly identified species, while only 1 assemblage sequence was detected. Since most human cases of cryptosporidiosis are caused by C. parvum and C. hominis and human cases of giardiasis are caused by G. duodenalis assemblage A and B, the domestic cats in the present study are likely to be of low zoonotic risk to pet owners in Perth. Risk analyses identified that elderly cats (more than 6 years) were more prone to Cryptosporidium and Giardia infections than kittens (less than 6 months) (P = 0.009). Clinical symptoms were not associated with the prevalence of Cryptosporidium and Giardia infections in cats. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Ethanol and Isopropanol in Concentrations Present in Hand Sanitizers Sharply Reduce Excystation of Giardia and Entamoeba and Eliminate Oral Infectivity of Giardia Cysts in Gerbils

    Science.gov (United States)

    Chatterjee, Aparajita; Bandini, Giulia; Motari, Edwin

    2015-01-01

    Enteric protozoan parasites, which are spread by the fecal-oral route, are important causes of diarrhea (Giardia duodenalis) and amebic dysentery (Entamoeba histolytica). Cyst walls of Giardia and Entamoeba have a single layer composed of fibrils of β-1,3-linked GalNAc and β-1,4-linked GlcNAc (chitin), respectively. The goal here was to determine whether hand sanitizers that contain ethanol or isopropanol as the active microbicide might reduce transmission of these parasites. We found that treatment with these alcohols with or without drying in a rotary evaporator (to model rapid evaporation of sanitizers on hands) kills 85 to 100% of cysts of G. duodenalis and 90 to 100% of cysts of Entamoeba invadens (a nonpathogenic model for E. histolytica), as shown by nuclear labeling with propidium iodide and failure to excyst in vitro. Alcohols with or without drying collapsed the cyst walls of Giardia but did not collapse the cyst walls of Entamoeba. To validate the in vitro results, we showed that treatment with alcohols eliminated oral infection of gerbils by 1,000 G. duodenalis cysts, while a commercial hand sanitizer (Purell) killed E. invadens cysts that were directly applied to the hands. These results suggest that expanded use of alcohol-based hand sanitizers might reduce the transmission of Giardia and Entamoeba. PMID:26282413

  7. Recognition of a 30,000 MW antigen of Giardia muris trophozoites by intestinal IgA from Giardia-infected mice.

    Science.gov (United States)

    Heyworth, M F; Pappo, J

    1990-08-01

    The principal aims of this work were (i) to identify the molecular weight (MW) of Giardia muris trophozoite antigens that are recognized by IgA in small intestinal secretions from G. muris-infected mice, and (ii) to determine whether mouse intestinal Giardia-specific IgA is directed against trophozoite surfaces. BALB/c mice were infected with G. muris cysts, and intestinal secretions were harvested from these mice at various times after the start of Giardia infection, and from uninfected mice. Flow cytometry showed that intestinal IgA from G. muris-infected mice, but not from uninfected mice, became bound to trophozoite surfaces in vitro. Western blotting of trophozoite proteins with mouse intestinal secretions showed that IgA from Giardia-infected mice reacted specifically with a broad protein band of approximately 30,000 MW. This finding suggests that one or more trophozoite proteins of approximately 30,000 MW are targets for intestinal antibody in mice infected with G. muris.

  8. Control of Giardia infections with ronidazole and intensive hygiene management in a dog kennel.

    Science.gov (United States)

    Fiechter, Ruth; Deplazes, Peter; Schnyder, Manuela

    2012-06-08

    Infections with the intestinal protozoan parasite Giardia in dogs and cats are common. Clinical signs vary from asymptomatic to small bowel diarrhea and associated discomfort. The control of infections in dogs is frequently a frustrating issue for animal owners and veterinarians. Drugs with antiprotozoal activity such as fenbendazole and metronidazole are recommended, however, they do not show 100% efficacy and superinfections occur regularly. Ronidazole is currently the drug of choice for the treatment of Tritrichomonas foetus in cats and there is now limited information available about its efficacy against Giardia spp. In the kennel investigated, dogs regularly showed loose feces and the presence of Giardia (assemblage C, renamed as G. canis) cysts. An elimination strategy of this parasite involving strict hygiene management and disinfection of the enclosures with 4-chlorine-M-cresol, oral treatment with ronidazole (30-50mg/kg BW bid for 7 days) and two shampooings (containing chlorhexidine) at the beginning and the end of the treatments was implemented for a group of 6 dogs. As a control another group of 7 dogs was transferred to the disinfected enclosures and shampooed, but left untreated. Dog feces were tested for the presence of Giardia cysts (SAF concentration technique) or Giardia antigen with a commercial ELISA (NOVITEC(®)) and a quick immunochromatography-based test (SensPERT(®)) before and between 5 and 40 days after the last treatment. All ronidazole-treated dogs were negative for Giardia cysts and antigen up to 26 days after the last treatment, while between 1 and 5 of the control animals tested positive in each of the test series. At this point, also dogs of the control group were again moved into clean enclosures, shampooed twice and treated with ronidazole. Five, 12 and 19 days after the last treatment, the dogs in the control group tested negative for Giardia cysts and antigen. However, all animals had again positive results at later time points

  9. Drinking Water Quality and Occurrence of Giardia in Finnish Small Groundwater Supplies

    Directory of Open Access Journals (Sweden)

    Tarja Pitkänen

    2015-08-01

    Full Text Available The microbiological and chemical drinking water quality of 20 vulnerable Finnish small groundwater supplies was studied in relation to environmental risk factors associated with potential sources of contamination. The microbiological parameters analyzed included the following enteric pathogens: Giardia and Cryptosporidium, Campylobacter species, noroviruses, as well as indicator microbes (Escherichia coli, intestinal enterococci, coliform bacteria, Clostridium perfringens, Aeromonas spp. and heterotrophic bacteria. Chemical analyses included the determination of pH, conductivity, TOC, color, turbidity, and phosphorus, nitrate and nitrite nitrogen, iron, and manganese concentrations. Giardia intestinalis was detected from four of the water supplies, all of which had wastewater treatment activities in the neighborhood. Mesophilic Aeromonas salmonicida, coliform bacteria and E. coli were also detected. None of the samples were positive for both coliforms and Giardia. Low pH and high iron and manganese concentrations in some samples compromised the water quality. Giardia intestinalis was isolated for the first time in Finland in groundwater wells of public water works. In Europe, small water supplies are of great importance since they serve a significant sector of the population. In our study, the presence of fecal indicator bacteria, Aeromonas and Giardia revealed surface water access to the wells and health risks associated with small water supplies.

  10. Effect of Giardia infection on growth and psychomotor development of children aged 0-5 years.

    Science.gov (United States)

    Simsek, Z; Zeyrek, F Yildiz; Kurcer, M A

    2004-04-01

    Giardiasis, an intestinal protozoan infection caused by Giardia intestinalis, is common in southeastern Anatolia, Turkey. In this cross-sectional survey, to investigate the role of giardiasis on growth and psychomotor development, we studied 160 children aged 0-5 years. Data were collected using a structured questionnaire, anthropometry, Ankara Developmental Screening Inventory, and laboratory analysis of fecal samples. The results showed that 50 per cent of the subjects were infected with at least one pathogen of intestinal parasitic infections. Giardia intestinalis was the most frequent pathogenic parasite. Giardia-infected children had a risk for stunted (OR = 7.67, 95 per cent CI = 2.25-26.16; p = 0.001) and poor psychomotor development (OR = 2.68, 95 per cent CI = 1.09-6.58; p = 0.030). The data indicate that Giardia intestinalis infection has an adverse impact on child linear growth and psychomotor development. In the primary healthcare centers, during the programme of the monitoring growth and developmental status of children, following children in terms of Giardia, diagnosis and treatment will have a positive effect on child health.

  11. Genotyping and subtyping of Giardia and Cryptosporidium isolates from commensal rodents in China.

    Science.gov (United States)

    Zhao, Z; Wang, R; Zhao, W; Qi, M; Zhao, J; Zhang, L; Li, J; Liu, A

    2015-05-01

    Cryptosporidium and Giardia are two important zoonotic intestinal parasites responsible for diarrhoea in humans and other animals worldwide. Rodents, as reservoirs or carriers of Cryptosporidium and Giardia, are abundant and globally widespread. In the present study, we collected 232 fecal specimens from commensal rodents captured in animal farms and farm neighbourhoods in China. We collected 33 Asian house rats, 168 brown rats and 31 house mice. 6.0% (14/232) and 8.2% (19/232) of these rodents were microscopy-positive for Giardia cysts and Cryptosporidium oocysts, respectively. All 14 Giardia isolates were identified as Giardia duodenalis assemblage G at a minimum of one or maximum of three gene loci (tpi, gdh and bg). By small subunit rRNA (SSU rRNA) gene sequencing, Cryptosporidium parvum (n = 12) and Cryptosporidium muris (n = 7) were identified. The gp60 gene encoding the 60-kDa glycoprotein was successfully amplified and sequenced in nine C. parvum isolates, all of which belonged to the IIdA15G1 subtype. Observation of the same IIdA15G1 subtype in humans (previously) and in rodents (here) suggests that rodents infected with Cryptosporidium have the potential to transmit cryptosporidiosis to humans.

  12. Molecular identification of Giardia duodenalis isolates from domestic dogs and cats in Wroclaw, Poland.

    Science.gov (United States)

    Piekarska, Jolanta; Bajzert, Joanna; Gorczykowski, Michał; Kantyka, Magdalena; Podkowik, Magdalena

    2016-09-01

    Giardia duodenalis (G. intestinalis) is a common protozoan causing gastrointestinal disorders in many species of mammals. The genus of Giardia has high molecular diversity. Dogs and cats, in addition to their typical infection with assemblages C, D and F, may be a reservoir of zoonotic assemblages (A and B). The aim of this study was a genetic characteristic of Giardia isolates of dogs and cats from the area of Wroclaw (Poland). A total of 128 and 33 faecal samples from dogs and cats, respectively, were analyzed by routine coprological methods. The animals were diagnosed on the presence of G. duodenalis antigens in faeces soluble with the use of SNAP Giardia (IDEXX Laboratories) immunosorbent assay. 27 DNA isolates of Giardia were subjected to molecular identification (PCR-RFLP). The prevalence of G. duodenalis was 21.1% (27/128) in dogs and 15.1% (5/33) in cats. In dogs, C assemblage was present in 18 (81%) positive stool samples, D assemblage in 2 (9%) samples, B assemblage present in one (4.5%), and mixed assemblages (C and D) occurred in one (4.5%) sample. F assemblage was found in 4 (80%) cats' positive stool samples and A assemblage occurred in one case (20%). Confirmation of the presence of A and B zoonotic assemblages suggests that infected pets can be a threat to human health. This study describes for the first time the presence of mixed infections within host-specific C and D assemblages in dogs in Poland.

  13. Low risk for transmission of zoonotic Giardia duodenalis from dogs to humans in rural Cambodia

    DEFF Research Database (Denmark)

    Inpankaew, Tawin; Schär, Fabian; Odermatt, Peter

    2014-01-01

    BACKGROUND: A number of epidemiological studies have demonstrated Giardia as prevalent in both humans and dogs worldwide and have postulated the occurrence of anthroponotic, zoonotic and animal-specific cycles of transmission, which may be geographically and regionally unique in its epidemiology.......: Overall, just over 2% of dogs harboured potentially zoonotic assemblages of G. duodenalis in the studied communities and hence pose a minimal zoonotic risk for the transmission of Giardia to humans.......BACKGROUND: A number of epidemiological studies have demonstrated Giardia as prevalent in both humans and dogs worldwide and have postulated the occurrence of anthroponotic, zoonotic and animal-specific cycles of transmission, which may be geographically and regionally unique in its epidemiology....... The aim of this study was to utilise molecular tools to determine the prevalence and compare genotypes of Giardia duodenalis infecting humans and dogs living in a previously identified Giardia-endemic village in rural Cambodia in order to ascertain zoonotic transmission risk. FINDINGS: The prevalence of G...

  14. Interleukin-17 receptor A (IL-17RA) as a central regulator of the protective immune response against Giardia

    NARCIS (Netherlands)

    Paerewijck, O. (Oonagh); Maertens, B. (Brecht); L. Dreesen (Leentje); Van Meulder, F. (Frederik); Peelaers, I. (Iris); Ratman, D. (Dariusz); Li, R.W. (Robert W.); E.W. Lubberts (Erik); K. De Bosscher; P. Geldhof (Peter)

    2017-01-01

    textabstractThe protozoan parasite Giardia is a highly prevalent intestinal pathogen with a wide host range. Data obtained in mice, cattle and humans revealed the importance of IL-17A in the development of a protective immune response against Giardia. The aim of this study was to further unravel the

  15. Factors promoting in vitro excystation of Giardia muris cysts.

    Science.gov (United States)

    Schaefer, F W; Rice, E W; Hoff, J C

    1984-01-01

    Giardia muris cysts, isolated from mouse faeces, excysted routinely at levels greater than 90%, when induced in 1X Hanks' supplemented with 17 mM glutathione, 29 mM L-cysteine-HCl, and 50 mM NaHCO3 for 30 minutes at 35 degrees C, followed by washing and suspension in trypsin-Tyrode's solution at pH 8.0. Although trypsin was not required in this final step, it enhanced the escape of the trophozoites from their cysts. G. muris excystation was dependent upon the length of the induction period, pH, oxidation-reduction potential and temperature. Optimal induction conditions for excystation were: an induction period of 5 to 30 min; pH of 2; 120 mV oxidation-reduction potential; and a temperature around 35 degrees C. A gradual decline in excystation occurred as pH and oxidation-reduction potential were changed to 7 and 57 mV, respectively. There was a pronounced increase in excystation percentages with increasing temperatures between 0 and 37 degrees C. At 40 degrees C and above, the G. muris cysts showed signs of inactivation. The thermal death point of G. muris cysts was determined to be about 54 degrees C. G. muris cysts showed no polarity; however, the tail or posterior trophozoite portion always emerged through one end of the cyst first. Cytokinensis began within the first hour after excystation. This method always produced extremely active, normal-looking G. muris trophozoites.

  16. Generation and characterization of monoclonal antibodies against Giardia muris trophozoites.

    Science.gov (United States)

    Heyworth, M F; Ho, K E; Pappo, J

    1989-11-01

    Mouse monoclonal antibodies (mAb) were produced against Giardia muris trophozoite surface antigens. To generate B-cell hybridomas, P3/NS1/1-Ag4-1 myeloma cells were fused with splenic lymphocytes from BALB/c mice that had been immunized parenterally with G. muris trophozoites. Hybridoma culture supernatants were screened for mAb by flow cytometry of G. muris trophozoites incubated with culture supernatant followed by fluorescein-conjugated anti-mouse IgG and IgM. Flow cytometry showed three types of trophozoite staining by mAb: (i) bright staining of greater than 90% of trophozoites, with aggregation of the organisms; (ii) bright staining of approximately 90% of trophozoites, with little or no aggregation; (iii) dull staining of approximately 20% of trophozoites, without aggregation. Western blotting of mAb on G. muris trophozoite antigens separated by polyacrylamide gel electrophoresis showed that a mAb exhibiting the third of these flow cytometry staining patterns recognized trophozoite antigens of MW approximately 31,000 and 35,000. Immunoprecipitation studies indicated that the same mAb specifically precipitated two 125I-labelled trophozoite surface antigens of MW approximately 30,000. Monoclonal antibodies generated in this study may facilitate the purification and biochemical characterization of trophozoite antigens that are targets for protective intestinal antibody in G. muris-infected mice.

  17. Giardia agilis: Ultrastructure of the Trophozoites in the Frog Intestine

    Directory of Open Access Journals (Sweden)

    Maria Inês L Sogayar

    1998-05-01

    Full Text Available Intestine samples of Bufo sp. tadpoles with parasitism confirmed for Giardia agilis were studied by transmission electron microscopy. The G. agilis trophozoites were long and thin. The plasma membrane was sometimes undulated and the cytoplasm, adjacent to the dorsal and ventral regions, showed numerous vacuoles. The two nuclei presented prominent nucleoli. The cytoplasm was electron-dense with free ribosomes, glycogen and rough endoplasmic reticulum-like structures. Polyhedral inclusions were observed in the cytoplasm and outside the protozoan; some of these inclusions exhibited membrane disruption. The flagella ultrastructure is typical, with the caudal pair accompanied by the funis. Next to the anterior pair, osmiophilic material was noticed. The ventro-lateral flange was short and thick, supported by the marginal plates that penetrated into its distal extremity; only its distal portion had adjacent osmiophilic filament. The G. agilis trophozoites showed the general subcellular feature of the genus. However, the ventro-lateral flange ultrastructure was an intermediate type between G. muris and G. duodenalis.

  18. Evaluation of Military Field-Water Quality. Volume 5. Infectious Organisms of Military Concern Associated with Consumption: Assessment of Health Risks, and Recommendations for Establishing Related Standards

    Science.gov (United States)

    1986-02-01

    influence duration, incidence, and severity of giardiasis.44 Acquired resistance in mice to Giardia muris has been demonstrated. 4 2 ’ 4 5 Human milk...ntaamoeba histoletica ........ ....................... 65 Giardia lamblia ............. ......................... 66 Summary- Ri•k-Assessment Results...Concentration in the Environment ......... .................. .. 227 References ................. ............................ .. 228 2. Giardia lamblia

  19. Administration of kefir-fermented milk protects mice against Giardia intestinalis infection.

    Science.gov (United States)

    Franco, Mariana Correa; Golowczyc, Marina A; De Antoni, Graciela L; Pérez, Pablo F; Humen, Martín; Serradell, María de los Angeles

    2013-12-01

    Giardiasis, caused by the protozoan Giardia intestinalis, is one of the most common intestinal diseases worldwide and constitutes an important problem for the public health systems of various countries. Kefir is a probiotic drink obtained by fermenting milk with 'kefir grains', which consist mainly of bacteria and yeasts that coexist in a complex symbiotic association. In this work, we studied the ability of kefir to protect mice from G. intestinalis infection, and characterized the host immune response to this probiotic in the context of the intestinal infection. Six- to 8-week-old C75BL/6 mice were separated into four groups: controls, kefir mice (receiving 1 : 100 dilution of kefir in drinking water for 14 days), Giardia mice (infected orally with 4×10(7) trophozoites of G. intestinalis at day 7) and Giardia-kefir mice (kefir-treated G. intestinalis-infected mice), and killed at 2 or 7 days post-infection. Kefir administration was able to significantly reduce the intensity of Giardia infection at 7 days post-infection. An increase in the percentage of CD4(+) T cells at 2 days post-infection was observed in the Peyer's patches (PP) of mice belonging to the Giardia group compared with the control and kefir groups, while the percentage of CD4(+) T cells in PP in the Giardia-kefir group was similar to that of controls. At 2 days post-infection, a reduction in the percentage of B220-positive major histocompatibility complex class II medium cells in PP was observed in infected mice compared with the other groups. At 7 days post-infection, Giardia-infected mice showed a reduction in RcFcε-positive cells compared with the control group, suggesting a downregulation of the inflammatory response. However, the percentages of RcFcε-positive cells did not differ from controls in the kefir and Giardia-kefir groups. An increase in IgA-positive cells was observed in the lamina propria of the kefir group compared with controls at 2 days post-infection. Interestingly, the

  20. Giardia spp. and Cryptosporidium spp. In the Ivaí Indigenous Land, Brazil.

    Science.gov (United States)

    Nishi, Letícia; Bergamasco, Rosângela; Toledo, Max Jean de Ornelas; Falavigna, Dina Lúcia Morais; Gomes, Mônica Lúcia; Mota, Lúcio Tadeu; Falavigna-Guilherme, Ana Lúcia

    2009-10-01

    The objective of this study was to investigate the occurrence of cysts of Giardia spp. and oocysts of Cryptosporidium spp. in waters of the Ivaí Indigenous Land, Brazil. Samples of river and spring water and of treated water were filtered and analyzed by direct immunofluorescence (Merifluor kit, Meridian Bioscience, Cincinnati, Ohio). Of 21 samples, 7 from each locality, 3 (3/7, 42.8%) from a river were positive for Giardia (mean concentration 2.57 cysts/L), and 1 (1/7, 14.3%) was positive for Cryptosporidium (6 oocysts/L). From springs, 1 sample (1/7, 14.3%) was positive for Cryptosporidium (6 oocysts/L). One sample (1/7, 14.3%) from treated water was positive for both, with 4 oocysts/L and 2 cysts/L. Giardia was the more frequent protozoan present.

  1. Risk assessment of Giardia in rivers of southern China based on continuous monitoring

    Institute of Scientific and Technical Information of China (English)

    Wei An; Dongqing Zhang; Shumin Xiao; Jianwei Yu; Min Yang

    2012-01-01

    The occurrence and risks of Giardia in China have been unclear to date,which has made it difficult to properly manage source water as well as to create reasonable drinking water standards.The levels of Giardia in river networks of several cities in Zhejiang Province,China were found to be in the range of 0-5 oocysts/10 L in the rainy season in 2008.The mortality due to Giardia infection for people in this region was calculated to be from 0 to 1.95 × 10-s persons using a conditional probability equation.Based on multiple unboiled water intake routes,the disability-adjusted life years (DALYs) due to Giardia infection for people who consumed conventionally treated water was 0.625 (95% CI:0.137-2.05) per 105 persons,with the symptom of hospitalization making the highest contribution to total DALYs (0.56 per 105 persons; 95% CI:0.122-1.84).The DALYs decreased to 0.425 (95% CI:0.137-2.05) per 105 persons per year for those consuming water treated with advanced technology.These values were lower than the acceptable risk (1.97 × 10-5 DALYs per year).This study revealed the risk of Giardia infection to the people in river networks of Zhejiang Province for the first time,and provides a method to evaluate the risk of Giardia infection.The results are useful for the modification of drinking water quality standards based on cost-benefit analysis.

  2. Common coinfections of Giardia intestinalis and Helicobacter pylori in non-symptomatic Ugandan children.

    Directory of Open Access Journals (Sweden)

    Johan Ankarklev

    Full Text Available BACKGROUND: The protozoan parasite Giardia intestinalis and the pathogenic bacterium Helicobacter pylori are well known for their high prevalences in human hosts worldwide. The prevalence of both organisms is known to peak in densely populated, low resource settings and children are infected early in life. Different Giardia genotypes/assemblages have been associated with different symptoms and H. pylori with induction of cancer. Despite this, not much data are available from sub-Saharan Africa with regards to the prevalence of different G. intestinalis assemblages and their potential association with H. pylori infections. METHODOLOGY/PRINCIPAL FINDINGS: Fecal samples from 427 apparently healthy children, 0-12 years of age, living in urban Kampala, Uganda were analyzed for the presence of H. pylori and G. intestinalis. G. intestinalis was found in 86 (20.1% out of the children and children age 1<5 years had the highest rates of colonization. H. pylori was found in 189 (44.3% out of the 427 children and there was a 3-fold higher risk of concomitant G. intestinalis and H. pylori infections compared to non-concomitant G. intestinalis infection, OR = 2.9 (1.7-4.8. No significant association was found in the studied population with regard to the presence of Giardia and gender, type of toilet, source of drinking water or type of housing. A panel of 45 G. intestinalis positive samples was further analyzed using multi-locus genotyping (MLG on three loci, combined with assemblage-specific analyses. Giardia MLG analysis yielded a total of five assemblage AII, 25 assemblage B, and four mixed assemblage infections. The assemblage B isolates were highly genetically variable but no significant association was found between Giardia assemblage type and H. pylori infection. CONCLUSIONS/SIGNIFICANCE: This study shows that Giardia assemblage B dominates in children in Kampala, Uganda and that the presence of H. pylori is an associated risk factor for G

  3. Occurrence of Cryptosporidium and Giardia genotypes and subtypes in raw and treated water in Portugal.

    Science.gov (United States)

    Lobo, M L; Xiao, L; Antunes, F; Matos, O

    2009-06-01

    Waterborne outbreaks of diarrhoeal illness reported worldwide are mostly associated with Cryptosporidium spp. and Giardia spp. Their presence in aquatic systems makes it essential to develop preventive strategies for water and food safety. This study was undertaken to monitor the presence of Cryptosporidium and Giardia in a total of 175 water samples, including raw and treated water from both surface and ground sources in Portugal. The samples were processed according to USEPA Method 1623 for immunomagnetic separation (IMS) of Cryptosporidium oocysts and Giardia cysts, followed by detection of oocysts/cysts by immunofluorecence (IFA) microscopy, PCR-based techniques were done on all water samples collected. Out of 175 samples, 81 (46.3%) were positive for Cryptosporidium and 67 (38.3%) for Giardia by IFA. Cryptosporidium spp. and G. duodenalis genotypes were identified by PCR in 37 (21.7%) and 9 (5.1%) water samples, respectively. C. parvum was the most common species (78.9%), followed by C. hominis (13.2%), C. andersoni (5.3%), and C. muris (2.6%). Subtype IdA15 was identified in all C. hominis-positive water samples. Subtyping revealed the presence of C. parvum subtypes IIaA15G2R1, IIaA16G2R1 and IIdA17G1. Giardia duodenalis subtype A1 was identified. The results of the present study suggest that Cryptosporidium spp. and Giardia spp. were widely distributed in source water and treated water in Portugal. Moreover, the results obtained indicate a high occurrence of human-pathogenic Cryptosporidium genotypes and subtypes in raw and treated water samples. Thus, water can be a potential vehicle in the transmission of cryptosporidiosis, and giardiasis of humans and animals in Portugal.

  4. Cryptosporidium spp. and Giardia sp. in aquatic mammals in northern and northeastern Brazil.

    Science.gov (United States)

    Borges, João Carlos; Lima, Danielle Dos; da Silva, Edson Moura; Moreira, André Lucas de Oliveira; Marmontel, Miriam; Carvalho, Vitor Luz; Amaral, Rodrigo de; Lazzarini, Stella Maris; Alves, Leucio Câmara

    2017-09-20

    Cryptosporidium and Giardia are protozoans that can infect humans and wild and domestic animals. Due to the growing importance of diseases caused by protozoan parasites in aquatic species, we aimed to evaluate the frequency of infection by Cryptosporidium spp. and Giardia sp. in aquatic and marine mammals in the northern and northeastern regions of Brazil. We collected 553 fecal samples from 15 species of wild-ranging and captive aquatic mammals in northern and northeastern Brazil. All samples were analyzed by the Kinyoun technique for identification of Cryptosporidium spp. oocysts. Giardia sp. cysts were identified by means of the centrifugal-flotation technique in zinc sulfate solution. Subsequently, all samples were submitted for direct immunofluorescence testing. The overall frequency of infection was 15.55% (86/553) for Cryptosporidium spp. and 9.04% (50/553) for Giardia sp. The presence of Cryptosporidium spp. was detected in samples from 5 species: neotropical river otter Lontra longicaudis (15.28%), giant otter Pteronura brasiliensis (41.66%), Guiana dolphin Sotalia guianensis (9.67%), Amazonian manatee Trichechus inunguis (16.03%), and Antillean manatee T. manatus (13.79%). Giardia sp. was identified in L. longicaudis (9.23%), P. brasiliensis (29.16%), pygmy sperm whale Kogia breviceps (100%), dwarf sperm whale K. sima (25%), S. guianensis (9.67%), T. inunguis (3.81%), and T. manatus (10.34%). This is the first report of Cryptosporidium spp. in L. longicaudis, P. brasiliensis, and S. guianensis, while the occurrence of Giardia sp., in addition to the 2 otter species, was also identified in manatees, thus extending the number of hosts susceptible to these parasitic agents.

  5. A comparison of Giardia microti and Spironucleus muris cysts in the vole: an immunocytochemical, light, and electron microscopic study.

    Science.gov (United States)

    Januschka, M M; Erlandsen, S L; Bemrick, W J; Schupp, D G; Feely, D E

    1988-06-01

    We have shown that cysts of the genus Spironucleus share many common morphological features with Giardia cysts including: 2-4 nuclei, flagellar axonemes, a distinct cyst wall, and they even display the same immunostaining as Giardia cysts when labeled with antibodies specific for Giardia cyst wall. A direct comparison of Spironucleus muris and Giardia microti cysts have revealed that cysts of S. muris are significantly smaller than cysts of G. miroti. At the ultrastructural level, the cyst walls are similar in fibrillar appearance, but the width of the S. muris cyst wall is significantly less than that of G. microti. The cysts of S. muris also differ from G. microti in that they contain a striated rootlet fiber, flagellar sheath, and numerous glycogen rosettes. Characteristic features of Giardia include the adhesive disc and median body. Although the cysts of Spironucleus and Giardia are similar in appearance, these unique morphological features can be used to distinguish between the 2 protozoa and should be employed in the detection of Giardia cysts in water samples.

  6. Efficacy of drugs against Giardia muris in mice Mus musculus naturally infected/ Eficácia de drogas contra Giardia muris em camundongos Mus musculus naturalmente infectados

    Directory of Open Access Journals (Sweden)

    Silvia Gonzalez Monteiro

    2008-08-01

    Full Text Available This study aimed to evaluate the efficacy of metronidazole, fenbendazole and secnidazole against Giardia muris in mice naturally infected. Forty mice of the species Mus musculus were divided in four groups of ten each, being group A non treated, the control group and groups B, C and D treated with 4mg/ml of metronidazole, fenbendazole and secnidazole, respectively. Two feces collection, on day 0 and on day 10 after treatment, were done in order to evaluate the efficacy of the drugs. Samples were analyzed by the centrifugal-flotation method with zinc sulfate. Efficacy of 97,05% for metronidazole, 98,30% for fenbendazole and 100% for secnidazole were observed in the study. According to the results it was concluded that the tested drugs were effective for the treatment of mice parasitized by Giardia muris.Este estudo visou avaliar a eficácia do metronidazol, fenbendazole e secnidazol contra Giardia muris em camundongos naturalmente infectados. Foram utilizados 40 camundongos da espécie Mus musculus divididos em quatro grupos de 10 animais cada, sendo grupo A, grupo controle, não tratados, e grupos B, C e D tratados com 4mg/ml de metronidazol, fenbendazole e secnidazol, respectivamente. Para avaliar a eficácia dos medicamentos foram realizadas duas coletas de fezes uma no dia zero e outra 10 dias após tratamento. As amostras foram processadas e analisadas a partir do método de centrífugo-flutuação com sulfato de zinco. No estudo observou-se eficácia de 97,05% para metronidazol, 98,30% para fenbendazole e 100% para secnidazol no tratamento de giardiase murina. Com base nos resultados concluí-se que as drogas testadas apresentaram eficácia no tratamento de camundongos parasitados por Giardia muris.

  7. Identification of Giardia species and Giardia duodenalis assemblages by sequence analysis of the 5.8S rDNA gene and internal transcribed spacers.

    Science.gov (United States)

    Cacciò, Simone M; Beck, Relja; Almeida, Andre; Bajer, Anna; Pozio, Edoardo

    2010-05-01

    PCR assays have been developed mainly to assist investigations into the epidemiology of Giardia duodenalis, the only species in the Giardia genus having zoonotic potential. However, a reliable identification of all species is of practical importance, particularly when water samples and samples from wild animals are investigated. The aim of the present work was to genotype Giardia species and G. duodenalis assemblages using as a target the region spanning the 5.8S gene and the 2 flanking internal transcribed spacers (ITS1 and ITS2) of the ribosomal gene. Primers were designed to match strongly conserved regions in the 3' end of the small subunit and in the 5' end of the large subunit ribosomal genes. The corresponding region (about 310 bp) was amplified from 49 isolates of both human and animal origin, representing all G. duodenalis assemblages as well as G. muris and G. microti. Sequence comparison and phylogenetic analysis showed that G. ardeae, G. muris, G. microti as well as the 7 G. duodenalis assemblages can be easily distinguished. Since the major subgroups within the zoonotic assemblages A and B can be identified by sequence analysis, this assay is also informative for molecular epidemiological studies.

  8. Prevalence and Associated Risk Factors of Giardia Infection among Indigenous Communities in Rural Malaysia

    Science.gov (United States)

    Choy, Seow Huey; Al-Mekhlafi, Hesham M.; Mahdy, Mohammed A. K.; Nasr, Nabil N.; Sulaiman, Maria; Lim, Yvonne A. L.; Surin, Johari

    2014-01-01

    This study was carried out to investigate the prevalence and risk factors of Giardia infection among indigenous people in rural Malaysia. Faecal samples were collected from 1,330 participants from seven states of Malaysia and examined by wet mount and formalin-ether sedimentation methods while demographic, socioeconomic and environmental information was collected using a pre-tested questionnaire. The overall prevalence of Giardia infection was 11.6% and was significantly higher among those aged ≤ 12 years compared to their older counterparts. Multivariate logistic regression identified age of ≤12 years, lacking of toilet at household, not washing hands before eating, not washing hands after playing with animals, not boiling water before consumption, bathing in the river, and not wearing shoes when outside as the significant risk factors of Giardia infection among these communities. Based on a multilocus genotyping approach (including tpi, gdh and bg gene sequences), 69 isolates were identified as assemblage A, and 69 as assemblage B. No association between the assemblages and presence of symptoms was found. Providing proper sanitation, as well as provision of clean drinking water and proper health education regarding good personal hygiene practices will help significantly in reducing the prevalence and burden of Giardia infection in these communities. PMID:25366301

  9. Saliva and sera IgA and IgG in Egyptian Giardia-infected children.

    Science.gov (United States)

    El-Gebaly, Naglaa Saad M; Halawa, Eman Fawzy; Moussa, Hanaa M Ezzat; Rabia, Ibrahim; Abu-Zekry, Maha

    2012-08-01

    Giardiasis is a gastrointestinal infection of wide distribution that is more prevalent in childhood. Easy and rapid diagnosis of giardiasis is essential for reduction of this infection. This cross-sectional study included 62 children in which collection of saliva, stool and serum samples was performed. An enzyme-linked immunosorbent assay (ELISA) technique was evaluated to detect IgA and IgG responses in both saliva and serum samples. Twenty-two children were positive for Giardia duodenalis infection by direct examination of faecal specimens, 20 non-infected and 20 infected with other parasites. Salivary and serum IgA and IgG responses against G. duodenalis infection were significantly higher in Giardia parasitized than non-Giardia parasitized children (p < 0.001). This concludes that specific salivary IgA may serve as a diagnostic tool and specific salivary IgG as a screening tool in monitoring the exposure of various populations to Giardia duodenalis. The advantage of salivary assays over serum immunoglobulin assay is being easy and non-invasive in sampling technique which is important especially for young children.

  10. Het rendement van de detectiemethode voor Cryptosporidium en Giardia in water

    NARCIS (Netherlands)

    Schets FM; Medema GJ; Schijven JF; MGB

    2004-01-01

    Nederlandse waterleidingbedrijven zijn verplicht om te berekenen of als gevolg van consumptie van drinkwater infectie met Cryptosporidium of Giardia kan optreden. De kans hierop moet kleiner dan een infectie per 10000 personen per jaar zijn. De berekening (risicoanalyse) wordt gebaseerd op de

  11. Consistency of direct microscopic examination and ELISA in detection of Giardia in stool specimen among children

    Directory of Open Access Journals (Sweden)

    Zohreh Torabi

    2014-09-01

    Full Text Available Objective: To investigate the consistency of direct microscopic examination and ELISA for determination of Giadia in stool specimen. Method: Study population consisted of children with any clinical symptoms of Giardia infestation since last two weeks. Fresh stool specimen was collected from each child. The stools specimens were assessed by two methods of direct microscopic examination and ELISA.The degree of agreement between direct stool exam and ELISA was calculated by Cohen's kappa coefficient. Results: In this study, 124 children with age range 2-12 years were investigated. A total of 64 (61.7% and 79 (65.7% of children had Giardia by direct stool exam and ELISA test respectively. There was association between frequency of constipation and Giardia infection (P=0.036. The Cohen's kappa coefficient calculated for degree of agreement between direct stool exam and ELISA showed κ=0.756 (P<0.001. Conclusions: The frequency of Giardia infection in symptomatic children was high and there was high agreement rate between ELISA and direct stool smear.

  12. Exogenous cytokines released by spleen and Peyer's patch cells removed from mice infected with Giardia muris.

    Science.gov (United States)

    Djamiatun, K; Faubert, G M

    1998-01-01

    The role that T and B lymphocytes play in the clearance of Giardia muris in the mouse model is well known, but the cytokines produced by CD4+ T cells in response to Giardia antigenic stimulation are unknown. In this study, we have determined how Giardia trophozoite antigenic crude extract and T cell mitogens can trigger the production of cytokines by Peyer's patch and spleen cells removed from infected animals. When Giardia trophozoite proteins were used to challenge the cells in vitro, IL-4, IL-5 and IFN-gamma were not detected in the culture supernatant. When the cells were challenged with Con-A, all three cytokines were released in vitro. However, the level of each cytokine released by the spleen or Peyer's patch cells varied with the latent, acute and elimination phases of the infection. The high levels of IL-4 and IL-5 released by Peyer's patch cells confirm the importance of IgA in the control of the infection. However, we propose that the relative success of G. muris in completing its life cycle in a primary infection might be due, in part, to the stimulation of a Th2-type response (IL-4, IL-5). A stronger Th1 response (IFN-gamma) may lead to a better control of the primary infection.

  13. Lymphocyte proliferation in Peyer's patches of Giardia muris-infected mice.

    OpenAIRE

    Hill, D R

    1990-01-01

    Gastrointestinal immune events in giardiasis are important in controlling infection. In this study, Peyer's patch lymphocytes from mice infected with Giardia muris developed specific, proliferative responses to G. muris antigen. This proliferation correlated with clearance of infection. Further understanding of the gut immune response will be helpful in developing immunoprophylactic strategies in the control of giardiasis.

  14. Clearance of Giardia muris infection in mice deficient in natural killer cells.

    OpenAIRE

    Heyworth, M F; Kung, J E; Eriksson, E C

    1986-01-01

    Immunocompetent C57BL/6J mice and beige mice (which are deficient in natural killer cells) were infected with Giardia muris. Both types of mice cleared G. muris infection at similar rates. This observation suggests that clearance of G. muris parasites from the mouse intestine is not mediated by natural killer cells.

  15. Prevalence and Multilocus Genotyping Analysis of Cryptosporidium and Giardia Isolates from Dogs in Chiang Mai, Thailand

    Directory of Open Access Journals (Sweden)

    Sahatchai Tangtrongsup

    2017-05-01

    Full Text Available The occurrence and zoonotic potential of Cryptosporidium spp. and Giardia duodenalis isolated from dogs in Chiang Mai, Thailand were determined. Fecal samples were collected from 109 dogs between July and August 2008. Cryptosporidium spp. infection was determined by immunofluorescent assay (IFA, PCR assays that amplify Cryptosporidium heat-shock protein 70 kDa (hsp70, and two PCR assays that amplify a small subunit-ribosomal RNA (SSU-rRNA. Giardia duodenalis infection was identified using zinc sulfate centrifugal flotation, IFA, and four PCR assays that amplify the Giardia glutamate dehydrogenase (gdh, beta-giardin (bg, and generic and dog-specific assays of triosephosphate isomerase (tpi genes. Overall prevalence of Cryptosporidium spp. and G. duodenalis was 31.2% and 45.9%, respectively. Sequence analysis of 22 Cryptosporidium-positive samples and 21 Giardia-positive samples revealed the presence of C. canis in 15, and C. parvum in 7, G. duodenalis Assemblage C in 8, D in 11, and mixed of C and D in 2 dogs. Dogs in Chiang Mai were commonly exposed to Cryptosporidium spp. and G. duodenalis. Cryptosporidium parvum can be isolated from the feces of dogs, and all G. duodenalis assemblages were dog-specific. Dogs could be a reservoir for a zoonotic Cryptosporidium infection in humans, but further studies will be required to determine the clinical and zoonotic importance.

  16. Molecular identification of Enterocytozoon bieneusi, Cryptosporidium, and Giardia in Brazilian captive birds.

    Science.gov (United States)

    da Cunha, Maria Júlia Rodrigues; Cury, Márcia Cristina; Santín, Mónica

    2017-02-01

    A total of 85 fecal samples from captive birds collected from October 2013 to September 2014 in Uberlândia and Belo Horizonte in the state of Minas Gerais (Brazil) were evaluated for the presence of Enterocytozoon bieneusi, Cryptosporidium, and Giardia by PCR. Of these, three birds were found positive for E. bieneusi (3.5%), two for Cryptosporidium (2.3%), and one for Giardia (1.2%). Two genotypes of E. bieneusi were detected by nucleotide sequence analysis of the ITS region, genotypes D and Peru 6 in a swan goose and in two rock pigeons, respectively. For Cryptosporidium and Giardia, nucleotide sequence analysis of the SSU rRNA identified Cryptosporidium baileyi and Duck genotype in a swan goose and a mandarin duck, respectively, and Giardia duodenalis assemblage A in a toco toucon. Our results demonstrate that human-pathogenic E. bieneusi genotypes D and Peru6 and G. duodenalis assemblage A are present in captive birds in Brazil, corroborating their potential role as a source of human infection and environmental contamination.

  17. Prevalence and Multilocus Genotyping Analysis of Cryptosporidium and Giardia Isolates from Dogs in Chiang Mai, Thailand.

    Science.gov (United States)

    Tangtrongsup, Sahatchai; Scorza, A Valeria; Reif, John S; Ballweber, Lora R; Lappin, Michael R; Salman, Mo D

    2017-05-10

    The occurrence and zoonotic potential of Cryptosporidium spp. and Giardia duodenalis isolated from dogs in Chiang Mai, Thailand were determined. Fecal samples were collected from 109 dogs between July and August 2008. Cryptosporidium spp. infection was determined by immunofluorescent assay (IFA), PCR assays that amplify Cryptosporidium heat-shock protein 70 kDa (hsp70), and two PCR assays that amplify a small subunit-ribosomal RNA (SSU-rRNA). Giardia duodenalis infection was identified using zinc sulfate centrifugal flotation, IFA, and four PCR assays that amplify the Giardia glutamate dehydrogenase (gdh), beta-giardin (bg), and generic and dog-specific assays of triosephosphate isomerase (tpi) genes. Overall prevalence of Cryptosporidium spp. and G. duodenalis was 31.2% and 45.9%, respectively. Sequence analysis of 22 Cryptosporidium -positive samples and 21 Giardia -positive samples revealed the presence of C. canis in 15, and C. parvum in 7, G. duodenalis Assemblage C in 8, D in 11, and mixed of C and D in 2 dogs. Dogs in Chiang Mai were commonly exposed to Cryptosporidium spp. and G. duodenalis . Cryptosporidium parvum can be isolated from the feces of dogs, and all G. duodenalis assemblages were dog-specific. Dogs could be a reservoir for a zoonotic Cryptosporidium infection in humans, but further studies will be required to determine the clinical and zoonotic importance.

  18. Prevalence and associated risk factors of Giardia infection among indigenous communities in rural Malaysia.

    Science.gov (United States)

    Choy, Seow Huey; Al-Mekhlafi, Hesham M; Mahdy, Mohammed A K; Nasr, Nabil N; Sulaiman, Maria; Lim, Yvonne A L; Surin, Johari

    2014-11-04

    This study was carried out to investigate the prevalence and risk factors of Giardia infection among indigenous people in rural Malaysia. Faecal samples were collected from 1,330 participants from seven states of Malaysia and examined by wet mount and formalin-ether sedimentation methods while demographic, socioeconomic and environmental information was collected using a pre-tested questionnaire. The overall prevalence of Giardia infection was 11.6% and was significantly higher among those aged ≤ 12 years compared to their older counterparts. Multivariate logistic regression identified age of ≤ 12 years, lacking of toilet at household, not washing hands before eating, not washing hands after playing with animals, not boiling water before consumption, bathing in the river, and not wearing shoes when outside as the significant risk factors of Giardia infection among these communities. Based on a multilocus genotyping approach (including tpi, gdh and bg gene sequences), 69 isolates were identified as assemblage A, and 69 as assemblage B. No association between the assemblages and presence of symptoms was found. Providing proper sanitation, as well as provision of clean drinking water and proper health education regarding good personal hygiene practices will help significantly in reducing the prevalence and burden of Giardia infection in these communities.

  19. Evaluation of immunofluorescence microscopy and enzyme-linked immunosorbent assay in detection of Cryptosporidium and Giardia infections in asymptomatic dogs

    DEFF Research Database (Denmark)

    Rimhanen-Finne, R.; Enemark, Heidi L.; Kolehmainen, J.

    2007-01-01

    The performance of immunofluorescence microscopy (IF) and enzyme-linked immunosorbent assay (ELISA) in canine feces was evaluated. IF and Cryptosporidium ELISA detected 10(5) oocysts/g, while the detection limit for Giardia ELISA was 10(4) cysts/g. The Cryptosporidium ELISA showed 94% specificity...... zoonotic character of Cryptosporidium and Giardia infections in 150 asymptomatic Finnish dogs from the Helsinki area were studied. The overall proportion of dogs positive for Cryptosporidium was 5% (7/150) and that for Giardia 5% (8/150). In dogs...

  20. Irritable bowel syndrome and chronic fatigue 6 years after giardia infection: a controlled prospective cohort study.

    Science.gov (United States)

    Hanevik, Kurt; Wensaas, Knut-Arne; Rortveit, Guri; Eide, Geir Egil; Mørch, Kristine; Langeland, Nina

    2014-11-15

    Functional gastrointestinal disorders and fatigue may follow acute infections. This study aimed to estimate the persistence, prevalence, and risk of irritable bowel syndrome and chronic fatigue 6 years after Giardia infection. We performed a controlled prospective study of a cohort of 1252 individuals who had laboratory-confirmed Giardia infection during a waterborne outbreak in 2004. In total, 748 cohort cases (exposed) and 878 matched controls responded to a postal questionnaire 6 years later (in 2010). Responses were compared to data from the same cohort 3 years before (in 2007). The prevalences of irritable bowel syndrome (39.4%) by Rome III criteria and chronic fatigue (30.8%) in the exposed group 6 years after giardiasis were significantly elevated compared with controls, with adjusted relative risks (RRs) of 3.4 (95% confidence interval [CI], 2.9-3.9) and 2.9 (95% CI, 2.3-3.4), respectively. In the exposed group, the prevalence of irritable bowel syndrome decreased by 6.7% (RR, 0.85 [95% CI, .77-.93]), whereas the prevalence of chronic fatigue decreased by 15.3% from 3 to 6 years after Giardia infection (RR, 0.69 [95% CI, .62-.77]). Giardia exposure was a significant risk factor for persistence of both conditions, and increasing age was a risk factor for persisting chronic fatigue. Giardia infection in a nonendemic setting is associated with an increased risk for irritable bowel syndrome and chronic fatigue 6 years later. The prevalences of both conditions decrease over time, indicating that this intestinal protozoan parasite may elicit very long-term, but slowly self-limiting, complications. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America.

  1. An audit of Cryptosporidium and Giardia detection in Scottish National Health Service Diagnostic Microbiology Laboratories.

    Science.gov (United States)

    Alexander, C L; Currie, S; Pollock, K; Smith-Palmer, A; Jones, B L

    2017-06-01

    Giardia duodenalis and Cryptosporidium species are protozoan parasites capable of causing gastrointestinal disease in humans and animals through the ingestion of infective faeces. Whereas Cryptosporidium species can be acquired locally or through foreign travel, there is the mis-conception that giardiasis is considered to be largely travel-associated, which results in differences in laboratory testing algorithms. In order to determine the level of variation in testing criteria and detection methods between diagnostic laboratories for both pathogens across Scotland, an audit was performed. Twenty Scottish diagnostic microbiology laboratories were invited to participate with questions on sample acceptance criteria, testing methods, testing rates and future plans for pathogen detection. Reponses were received from 19 of the 20 laboratories representing each of the 14 territorial Health Boards. Detection methods varied between laboratories with the majority performing microscopy, one using a lateral flow immunochromatographic antigen assay, another using a manually washed plate-based enzyme immunoassay (EIA) and one laboratory trialling a plate-based EIA automated with an EIA plate washer. Whereas all laboratories except one screened every stool for Cryptosporidium species, an important finding was that significant variation in the testing algorithm for detecting Giardia was noted with only four laboratories testing all diagnostic stools. The most common criteria were 'travel history' (11 laboratories) and/or 'when requested' (14 laboratories). Despite only a small proportion of stools being examined in 15 laboratories for Giardia (2%-18% of the total number of stools submitted), of interest is the finding that a higher positivity rate was observed for Giardia than Cryptosporidium in 10 of these 15 laboratories. These findings highlight that the underreporting of Giardia in Scotland is likely based on current selection and testing algorithms.

  2. 42 CFR 493.917 - Parasitology.

    Science.gov (United States)

    2010-10-01

    ... vermicularis Entamoeba histolytica Entamoeba coli Giardia lamblia Endolimax nana Dientamoeba fragilis Iodamoeba... Diphyllobothrium latum Cryptosporidium sp. Plasmodium falciparum (3) For laboratories specified in paragraph (a)(1...

  3. Occurrence of Cryptosporidium and Giardia in domestic animals in peri-urban communities of Kafue district, Zambia

    DEFF Research Database (Denmark)

    Siwila, J.; Phiri, I. G. K.; Enemark, Heidi L.

    2013-01-01

    /148), goats (5.9%; 1/17), dogs (25.0%; 5/20) and ducks (6.7%; 2/30). Diarrhoea was not associated with either infection. Age was also not associated with either infection except in dogs where Giardia infection was only detected in animals aged less than six months (p=0.009). It is concluded from this study......Cryptosporidium spp. and Giardia duodenalis are important parasites infecting a wide range of domestic animals worldwide. The aim of the present study was to determine the occurrence of Cryptosporidium spp. and Giardia parasites in different domestic animals living in close contact with humans...... within rural/semiurban communities in Kafue district in Zambia. A single faecal sample per animal was collected from pigs, goats, dogs, ducks, chickens and pigeons and analysed by Merifluor Cryptosporidium/Giardia immunofluorescence antibody assay for the simultaneous detection of these parasites...

  4. Occurrence of Cryptosporidium and Giardia in domestic animals in peri-urban communities of Kafue district, Zambia

    DEFF Research Database (Denmark)

    Siwila, J.; Phiri, I. G. K.; Enemark, Heidi L.

    2013-01-01

    Cryptosporidium spp. and Giardia duodenalis are important parasites infecting a wide range of domestic animals worldwide. The aim of the present study was to determine the occurrence of Cryptosporidium spp. and Giardia parasites in different domestic animals living in close contact with humans...... within rural/semiurban communities in Kafue district in Zambia. A single faecal sample per animal was collected from pigs, goats, dogs, ducks, chickens and pigeons and analysed by Merifluor Cryptosporidium/Giardia immunofluorescence antibody assay for the simultaneous detection of these parasites....... The faecal consistency was noted and scored as non-diarrhoeic or diarrhoeic. A total of 236 samples were collected. Cryptosporidium spp. oocysts were detected in pigs (11.5%, 17/148), goats (5.9%; 1/17), ducks (10.0%; 3/30) and chickens (14.3%; 2/14) while Giardia cysts were detected in pigs (8.1%; 12...

  5. Comparison of antibody and cytokine responses to primary Giardia muris infection in H-2 congenic strains of mice.

    Science.gov (United States)

    Venkatesan, P; Finch, R G; Wakelin, D

    1996-11-01

    The course of primary infections with Giardia muris differs between BALB and B10 H-2 congenic strains of mice. In the first 3 weeks of infection, there is a more rapid decline in intestinal trophozoite and fecal cyst counts in B10 strains than in BALB strains. To determine whether this difference could be explained by variation in specific antibody responses, both secretory immunoglobulin A (IgA) and serum antibody responses were compared between these strains. No significant differences in the timing, titer, or specificity of secretory or serum antibodies were found. However, on comparing specific anti-G. muris serum IgG subclass responses, we found that B10 strains produced IgG2a while BALB strains produced IgG1, suggesting differential involvement of T helper 1 and 2 subsets of lymphocytes. When cells harvested from mesenteric lymph nodes were stimulated with concanavalin A in vitro, both gamma interferon and interleukin-5 were secreted by cells from B10 mice, but only interleukin-5 was secreted by cells from BALB/c mice. Specific blockade of gamma interferon by monoclonal antibody administered to B10 mice resulted in an enhanced intensity of infection.

  6. Incidence of and risks associated with Giardia infections in herds on dairy farms in the New York City Watershed

    Directory of Open Access Journals (Sweden)

    Schaaf Stephanie

    2010-06-01

    Full Text Available Abstract Background The primary aims of this study were to determine the incidence of Giardia infections in dairy herds on farms in the New York City Watershed region and to evaluate risk factors associated with infections. Because co-infections of Giardia and Cryptosporidium spp. are common in this population, we also evaluated the effect of herd infection status on Giardia infections. Methods Farms were grouped into three cohorts based on their prior infection status with Giardia and/or Cryptosporidium spp. The sampling plan included collecting fecal samples from all calves below 30 days of age and proportional sampling of calves, young stock, and adults. A total of 10,672 fecal samples were collected and analyzed for the presence of Giardia cysts using zinc sulfate flotation. Herds enrolled in the study were sampled seasonally for a study period of two years. The probability of shedding cysts past a certain age and the factors that influenced the likelihood of shedding were evaluated using survival analysis. Linear regression was used to evaluate factors that were associated with the intensity of shedding. Results The majority of Giardia infections occurred in calves within their first 180 days of age, with the most number of calves shedding Giardia cysts between 11 and 20 days of age. The incidence of shedding of Giardia cysts ranged from 0.0004 per animal day for cattle in the low risk cohort to 0.0011 per animal day for cattle in the high risk cohort. The likelihood of shedding was influenced by the prior infection status of the herd and the season of collection. Infected animals shed on average 9,658 cysts/gram and the intensity of shedding Giardia cysts varied significantly with the age (p Conclusion Giardia infections are common in dairy herds in the New York City watershed, particularly in calves less than 6 months of age. Seasonality may be an important factor in the perpetuation of infections based on changes in management practices

  7. [Occurrence of Giardia species and genotypes in humans and animals in Wielkopolska region, Poland].

    Science.gov (United States)

    Solarczyk, Piotr

    2009-01-01

    Giardia is the most common intestinal protozoan parasite found in humans and animals worldwide. Although it has been known for three hundred years, the nomenclature, taxonomy, host specificity, and pathogenicity of Giardia still arouse numerous controversies and ambiguities. Giardia is classified into six species, that are characterised by various ranges of hosts. The most dubious species is G. intestinalis, which includes a dozen or so genotypes, and only two of them (genotype A and B) have wide ranges of hosts, including humans. Moreover, in some genotype assemblages of G. intestinalis certain subgenotypes were distinguished and it was proven that in the same host species various subgenotypes of this parasite may occur. Bearing in mind the significant genetic heterogeneity of G. intestinalis and the fact that various genotypes and subgenotypes of this parasite are characterised by the broad or narrow host specificity, the data concerning the frequency of giardiosis occurrence are insufficient. It is necessary to use molecular biology techniques in order to define the genotype and/or the subgenotype of G. intestinalis that are found in humans and in certain animal species. Furthermore, since more and more pieces of evidence connected with a possibility of the sexual recombination of Giardia are gathered, it is unknown if genotypes and subgenotypes of this parasite are stable in time. The aim of this thesis was to define the frequency of Giardia occurrence in humans and animals in Wielkopolska region, to identify species and genotypes of Giardia that occur in humans and animals, as well as to obtain an axenic culture of the chosen isolates of Giardia from animals and to compare the sequence of the beta-giardin gene fragment obtained from the DNA isolated from cysts and trophozoites in order to check if the axenisation of G. intestinalis leads to the selection of genotypes or if Giardia genotypes are stable in time. Altogether, 2183 faecal samples were examined for

  8. Determination of the level of parasitic infection (Cryptosporidium and Giardia of the vegetables marketed in Ilam city

    Directory of Open Access Journals (Sweden)

    Moyad Avazpoor

    2015-01-01

    Full Text Available Background: Infected with intestinal parasites is one of the most important health and economical problems, which could have different effects, such as diarrheal diseases or death associated. The purpose of this study was to determine the level of prevalence of Cryptosporidium and Giardia parasites in the vegetable marketed in Ilam city. Methods: This study was performed on 280 samples of fresh vegetables and lettuce in Ilam. The samples were taken at the level of 500 grams from the places where vegetables and lettuce are sold. Micro liters of each sample was placed on the slide using automatic micropipette, and Logel and Zyl-Nelson stainings were performed in order to identify Cryptosporidium and Giardia. Results: From 200 samples, 54 samples were contaminated to Cryptosporidium oocyte and 13 samples to Giardia cysts. From 80 lettuce samples also 32 samples were contaminated to Cryptosporidium oocyte, and 6 samples contaminated to Giardia cysts. The results showed that the overall infection was 37%. Infection with Giardia cysts was 6.8% and infection with Cryptosporidium oocyte was 30.7%, and Cryptosporidium infection rates in vegetables and lettuce were different. This difference was statistically significant (P<0.05. Conclusion: As a result of this research it is determined that the prevalence of Giardia and Cryptosporidium in Ilam vegetables is significantly higher, and the contamination of lettuce is far greater. Therefore, authorities should be more attentive to the field of education and the control of parasitic diseases.

  9. Giardia in mountain gorillas (Gorilla beringei beringei), forest buffalo (Syncerus caffer), and domestic cattle in Volcanoes National Park, Rwanda.

    Science.gov (United States)

    Hogan, Jennifer N; Miller, Woutrina A; Cranfield, Michael R; Ramer, Jan; Hassell, James; Noheri, Jean Bosco; Conrad, Patricia A; Gilardi, Kirsten V K

    2014-01-01

    Mountain gorillas (Gorilla beringei beringei) are critically endangered primates surviving in two isolated populations in protected areas within the Virunga Massif of Rwanda, Uganda, the Democratic Republic of Congo, and in Bwindi Impenetrable National Park in Uganda. Mountain gorillas face intense ecologic pressures due to their proximity to humans. Human communities outside the national parks, and numerous human activities within the national parks (including research, tourism, illegal hunting, and anti-poaching patrols), lead to a high degree of contact between mountain gorillas and wildlife, domestic animals, and humans. To assess the pathogen transmission potential between wildlife and livestock, feces of mountain gorillas, forest buffalo (Syncerus caffer nanus), and domestic cattle (Bos taurus) in Rwanda were examined for the parasites Giardia and Cryptosporidium. Giardia was found in 9% of mountain gorillas, 6% of cattle, and 2% of forest buffalo. Our study represents the first report of Giardia prevalence in forest buffalo. Cryptosporidium-like particles were also observed in all three species. Molecular characterization of Giardia isolates identified zoonotic genotype assemblage B in the gorilla samples and assemblage E in the cattle samples. Significant spatial clustering of Giardia-positive samples was observed in one sector of the park. Although we did not find evidence for transmission of protozoa from forest buffalo to mountain gorillas, the genotypes of Giardia samples isolated from gorillas have been reported in humans, suggesting that the importance of humans in this ecosystem should be more closely evaluated.

  10. Molecular Characterization of Cryptosporidium Species and Giardia duodenalis from Symptomatic Cambodian Children

    Science.gov (United States)

    Moore, Catrin E.; Elwin, Kristin; Phot, Nget; Seng, Chanthou; Mao, Saroeun; Suy, Kuong; Kumar, Varun; Nader, Johanna; Bousfield, Rachel; Perera, Sanuki; Bailey, J. Wendi; Beeching, Nicholas J.; Day, Nicholas P. J.; Parry, Christopher M.; Chalmers, Rachel M.

    2016-01-01

    Background In a prospective study, 498 single faecal samples from children aged under 16 years attending an outpatient clinic in the Angkor Hospital for Children, northwest Cambodia, were examined for Cryptosporidium oocysts and Giardia cysts using microscopy and molecular assays. Methodology/Principal Findings Cryptosporidium oocysts were detected in 2.2% (11/498) of samples using microscopy and in 7.7% (38/498) with molecular tests. Giardia duodenalis cysts were detected in 18.9% (94/498) by microscopy and 27.7% (138/498) by molecular tests; 82% of the positive samples (by either method) were from children aged 1–10 years. Cryptosporidium hominis was the most common species of Cryptosporidium, detected in 13 (34.2%) samples, followed by Cryptosporidium meleagridis in 9 (23.7%), Cryptosporidium parvum in 8 (21.1%), Cryptosporidium canis in 5 (13.2%), and Cryptosporidium suis and Cryptosporidium ubiquitum in one sample each. Cryptosporidium hominis and C. parvum positive samples were subtyped by sequencing the GP60 gene: C. hominis IaA16R6 and C. parvum IIeA7G1 were the most abundant subtypes. Giardia duodenalis was typed using a multiplex real-time PCR targeting assemblages A and B. Assemblage B (106; 76.8% of all Giardia positive samples) was most common followed by A (12.3%) and mixed infections (5.1%). Risk factors associated with Cryptosporidium were malnutrition (AOR 9.63, 95% CI 1.67–55.46), chronic medical diagnoses (AOR 4.51, 95% CI 1.79–11.34) and the presence of birds in the household (AOR 2.99, 95% CI 1.16–7.73); specifically C. hominis (p = 0.03) and C. meleagridis (p<0.001) were associated with the presence of birds. The use of soap was protective against Giardia infection (OR 0.74, 95% CI 0.58–0.95). Conclusions/Significance This is the first report to describe the different Cryptosporidium species and subtypes and Giardia duodenalis assemblages in Cambodian children. The variety of Cryptosporidium species detected indicates both

  11. Efficacy of drugs against Giardia muris in mice Mus musculus naturally infected/
    Eficácia de drogas contra Giardia muris em camundongos Mus musculus naturalmente infectados

    OpenAIRE

    Silvia Gonzalez Monteiro; Régis Adriel Zanette; Camila Belmonte Oliveira; Marcos Kipper da Silva; Aleksandro Schafer da Silva

    2008-01-01

    This study aimed to evaluate the efficacy of metronidazole, fenbendazole and secnidazole against Giardia muris in mice naturally infected. Forty mice of the species Mus musculus were divided in four groups of ten each, being group A non treated, the control group and groups B, C and D treated with 4mg/ml of metronidazole, fenbendazole and secnidazole, respectively. Two feces collection, on day 0 and on day 10 after treatment, were done in order to evaluate the efficacy of the drugs. Samples w...

  12. Evidence from bioinformatics, expression and inhibition studies of phosphoinositide-3 kinase signalling in Giardia intestinalis

    Directory of Open Access Journals (Sweden)

    Crompton Mark R

    2006-05-01

    Full Text Available Abstract Background Giardia intestinalis is a parasitic protozoan and major cause of diarrhoeal disease. Disease transmission is dependent on the ability of the parasite to differentiate back and forth between an intestine-colonising trophozoite and an environmentally-resistant infective cyst. Our current understanding of the intracellular signalling mechanisms that regulate parasite replication and differentiation is limited, yet such information could suggest new methods of disease control. Phosphoinositide-3 kinase (PI3K signalling pathways have a central involvement in many vital eukaryotic processes, such as regulation of cell growth, intracellular membrane trafficking and cell motility. Here we present evidence for the existence of functional PI3K intracellular signalling pathways in G. intestinalis. Results We have identified and characterised two genes, Gipi3k1 and Gipi3k2, which encode putative PI3Ks. Both genes are expressed in trophozoites and encysting cells, suggesting a possible role of GiPI3K1 and GiPI3K2 in regulating giardial growth and differentiation. Extensive nucleotide and amino acid sequence characterisation predicts that both encoded PI3Ks are functional as indicated by the presence of highly conserved structural domains and essential catalytic residues. The inhibitory effect of the PI3K inhibitor LY294002 on trophozoite proliferation also supports their functionality. Phylogenetic analysis supports the identity of GiPI3K1 as a Class I isoform and GiPI3K2 as a Class III isoform. In addition, giardial genes encoding putative homologues of phosphoinositide-metabolising enzymes such as PTEN, MTM, PIPkin and PI 5-phosphatase as well as downstream effectors with phosphoinositide-binding domains have been identified, placing GiPI3K1 and GiPI3K2 in a broader signalling context. Compared with twenty-six PI3Ks from other organisms, GiPI3K1 and GiPI3K2 are unique in that they contain large insertions within their highly conserved

  13. High occurrence of Blastocystis sp. subtypes 1-3 and Giardia intestinalis assemblage B among patients in Zanzibar, Tanzania.

    Science.gov (United States)

    Forsell, Joakim; Granlund, Margareta; Samuelsson, Linn; Koskiniemi, Satu; Edebro, Helén; Evengård, Birgitta

    2016-06-29

    Blastocystis is a common intestinal parasite with worldwide distribution but the distribution of Blastocystis and its subtypes in East Africa is largely unknown. In this study, we investigate the distribution of Blastocystis subtypes in Zanzibar, Tanzania and report the prevalence of intestinal parasites using both molecular methods and microscopy. Stool samples were collected from both diarrhoeic and non-diarrhoeic outpatients in Zanzibar. In addition to microscopy, real-time PCR for Blastocystis, Entamoeba histolytica and E. dispar, Giardia intestinalis, Cryptosporidium spp., and Dientamoeba fragilis was used. Blastocystis subtypes were determined by a conventional PCR followed by partial sequencing of the SSU-rRNA gene. Genetic assemblages of Giardia were determined by PCR with assemblage specific primers. Intestinal parasites were detected in 85 % of the 174 participants, with two or more parasites present in 56 %. Blastocystis sp. and Giardia intestinalis were the most common parasites, identified by PCR in 61 and 53 % of the stool samples respectively, but no correlation between carriage of Blastocystis and Giardia was found. The Blastocystis subtype distribution was ST1 34.0 %, ST2 26.4 %, ST3 25.5 %, ST7 0.9 %, and 13.2 % were positive only by qPCR (non-typable). The Giardia genetic assemblages identified were A 6.5 %, B 85 %, A + B 4.3 %, and non-typable 4.3 %. The detection rate with microscopy was substantially lower than with PCR, 20 % for Blastocystis and 13.8 % for Giardia. The prevalence of Blastocystis increased significantly with age while Giardia was most prevalent in children two to five years old. No correlation between diarrhoea and the identification of Giardia, Blastocystis, or their respective genetic subtypes could be shown and, as a possible indication of parasite load, the mean cycle threshold values in the qPCR for Giardia were equal in diarrhoeic and non-diarrhoeic patients. Carriage of intestinal parasites was very

  14. New system for higher recovery rate of water borne Cryptosporidium oocysts and Giardia cysts

    DEFF Research Database (Denmark)

    Al-Sabi, Mohammad Nafi Solaiman; Gad, Jens; Klinting, Mette

    2012-01-01

    Background: The two most common water borne pathogenic protozoa, Cryptosporidium and Giardia, cause diarrhea worldwide. Detecting these parasites in water samples depends on effective parasite recovery from the water matrix. The reported low recovery rates of the currently used filter methods...... motivate the development of systems with higher recovery rates. Materials and methods: Five replicates of IMS purified Cryptosporidium oocysts and Giardia cysts (N=2x103) were injected into a specially coated filter unit with a carefully chosen pore size. Following filtration, sonication was performed...... were 85% were recorded when the filter was sonicated. Sonication usually affects parasite viability but could be tuned into a useful tool for enhanced backwash collection of parasites using a specially constructed filter unit and a sonication protocol. The filtration...

  15. Review of cryptosporidium and giardia in the eastern part of Europe, 2016

    DEFF Research Database (Denmark)

    Plutzer, Judit; Lassen, Brian; Jokelainen, Pikka

    2018-01-01

    Introduction: This paper reviews the current knowledge and understanding of Cryptosporidium spp. an d Giardia spp. in humans, animals and the environment in 10 countries in the eastern part of Europe: Bosnia and Herzegovina, Croatia, Czech Republic, Estonia, Hungary, Latvia, Poland, Romania, Serbia...... and Slovenia. Methods: Published scientific papers and conference proceedings from the international and local literature, official national health service reports, national databases and doctoral theses in local languages were reviewed to provide an extensive overview on the epidemiology, diagnostics...... and research on these pathogens, as well as analyse knowledge gaps and areas for further research. Results: Cryptosporidium spp. and Giardia spp. were found to be common in eastern Europe, but the results from different countries are difficult to compare because of variations in reporting practices...

  16. Terminalia ferdinandiana extracts as inhibitors of Giardia duodenalis proliferation: a new treatment for giardiasis.

    Science.gov (United States)

    Rayan, P; Matthews, B; McDonnell, P A; Cock, I E

    2015-07-01

    Giardisis is a debilitating disease caused by gastrointestinal parasites of the genus Giardia. High-antioxidant T. ferdinandiana fruit extracts were investigated for the ability to block Giardia duodenalis growth. Methanolic and aqueous extracts had the most potent growth inhibitory activity (IC50 values of approximately 700 and 140 μg/ml, respectively). Ethyl acetate and chloroform extracts also inhibited G. duodenalis growth, albeit with lower potency. The hexane extract was completely devoid of G. duodenalis growth inhibitory activity. All extracts were nontoxic in the Artemia fransiscana bioassay. Nontargeted HPLC-quadrupole time-of-flight (QTOF) mass spectroscopy (with screening against three compound databases) putatively identified 17 compounds in all of the inhibitory extracts but not in the inactive hexane extract. The low toxicity of the Terminalia ferdinandiana fruit extracts and their potent G. duodenalis growth inhibitory bioactivity indicate their potential as medicinal agents in the treatment and prevention of this disease.

  17. Cryptosporidium, Giardia and Enterocytozoon bieneusi in cats from Bogota (Colombia) and genotyping of isolates.

    Science.gov (United States)

    Santín, Mónica; Trout, James M; Vecino, Jesús A Cortés; Dubey, J P; Fayer, Ronald

    2006-11-05

    The prevalence of Cryptosporidium, Giardia, and Enterocytozoon bieneusi in cats from Bogota (Colombia) was determined from fecal specimens and scrapings of duodenal and ileal mucosa screened by PCR. All PCR-positive specimens were sequenced to determine the genotype(s) present. Of 46 cats, 6 (13%) were positive for Cryptosporidium, 5 (11%) were infected with C. felis and one (2%) with C. muris. Three (6.5%) cats were infected with Giardia duodenalis Assemblage F. Eight (17%) cats were infected with four genotypes of E. bieneusi: genotype D-like (9%), K (4%), Peru 10 (2%), and Peru 5 (2%). This is the first report on the presence of zoonotic species/genotypes of Cryptosporidium and E. bieneusi in cats in Colombia.

  18. Detection of giardine gene in local isolates of Giardia duodenalis by polymerase chain reaction (PCR).

    Science.gov (United States)

    Latifah, I; Teoh, K Y; Wan, K L; Rahmah, M; Normaznah, Y; Rohani, A

    2005-12-01

    Giardia duodenalis is an intestinal parasite that causes diarrhoea and malabsorption in children. The parasite also infects AIDS patients with a weak immune system. A study was carried out on six local isolates of Giardia duodenalis (110, 7304, 6304, M007, 2002 and 6307) from faeces of Orang Asli patients admitted to the Gombak Hospital. WB, a reference pathogenic strain from human and G. muris from a wild mouse, were commercially obtained from the American Type Culture Collection (ATCC). All the isolates were cultured axenically in TYI-S-33 medium. Two sets of primers were used for the techniques: primers LP1 and RP1 and primers LP2 and RP2. The sets of primers amplified giardine gene of 171 bp and 218 bp in sizes respectively. The study showed that the two sets of primers could detect G. duodenalis to the genus and species level specifically.

  19. Genome and transcriptome studies of the protozoan parasites Trypanosoma cruzi and Giardia intestinalis

    OpenAIRE

    Franzén, Oscar

    2012-01-01

    Trypanosoma cruzi and Giardia intestinalis are two human pathogens and protozoan parasites responsible for the diseases Chagas disease and giardiasis, respectively. Both diseases cause su ering and illness in several million individuals. The former disease occurs primarily in South America and Central America, and the latter disease occurs worldwide. Current therapeutics are toxic and lack e cacy, and potential vaccines are far from the market. Increased knowledge about the bio...

  20. Evaluation of faecal sampling methods for the analysis of Giardia sp. in companion animals

    OpenAIRE

    Santos, Ana Rita Ruas dos

    2016-01-01

    Dissertação de Mestrado Integrado em Medicina Veterinária Giardiosis is a zoonosis with a worldwide distribution, responsible for gastrointestinal disease in both humans and animals. Transmitted by contaminated water and food, Giardia represents a risk to veterinary and public health. Because of its prevalence in companion animals, veterinarians and animal owners awareness of the importance of its identification and treatment in infected animals, made it an important part of th...

  1. Comparison of animal infectivity and excystation as measures of Giardia muris cyst inactivation by chlorine.

    OpenAIRE

    Hoff, J C; Rice, E W; Schaefer, F W

    1985-01-01

    In this study, in vitro excystation and mouse infectivity were compared as methods for quantitatively determining the viability of Giardia muris cysts before and after exposure to free residual chlorine. The mouse infectivity results show that very few cysts (1 to 15) constitute an infectious dose. The results of the inactivation studies indicate that in vitro excystation is an adequate indication of G. muris cyst infectivity for the host and can be used to determine the effects of disinfecta...

  2. Phagocytosis of Giardia muris by macrophages in Peyer's patch epithelium in mice.

    OpenAIRE

    Owen, R L; Allen, C L; Stevens, D P

    1981-01-01

    No mechanism for the initiation of immunological clearance of Giardia from the mammalian intestinal tract has been identified. In normal and nude mice experimentally infected with G. muris, we examined antigen-sampling epithelium over Peyer's patch follicles by electron microscopy for evidence of interaction between G. muris and lymphoid cells. Invading G. muris were found in the epithelium near dying or desquamating columnar cells. Macrophages beneath the basal lamina extended pseudopods int...

  3. Cytokines, antibodies and histopathological profiles during Giardia infection and VSP-based vaccination.

    Science.gov (United States)

    Serradell, Marianela C; Gargantini, Pablo R; Saura, Alicia; Oms, Sergio R; Rupil, Lucía L; Berod, Luciana; Sparwasser, Tim; Luján, Hugo D

    2018-03-19

    Giardiasis is one of the most common human intestinal diseases worldwide. Several experimental animals have been used to evaluate Giardia infections, with gerbils ( Meriones unguiculatus ) being the most valuable model due to their high susceptibility to Giardia infection, abundant shedding of cysts, and pathophysiological alterations and signs of disease similar to those observed in humans. Here we report cytokine and antibody profiles both during the course of Giardia infection in gerbils and after immunization with a novel oral vaccine comprising a mixture of purified Variant-specific Surface Proteins (VSPs). Transcript levels of representative cytokines of different immune profiles as well as macro- and micro-tissue alterations were assessed in Peyer's patches, mesenteric lymph nodes and spleens. During infection, cytokine responses showed a biphasic profile: an early induction of Th1 (IFN-γ, IL-1β, IL-6 and TNF), Th17 (IL-17) and Th2 (IL-4) cytokines, together with intestinal alterations typical of inflammation, followed by a shift toward a predominant Th2 (IL-5) response, likely associated with a counter-regulatory mechanism. Conversely, immunization with an oral vaccine comprising the entire repertoire of VSPs specifically showed high levels of IL-17, IL-6, IL-4 and IL-5, without obvious signs of inflammation. Both immunized and infected animals developed local (intestinal S-IgA) and systemic (serum IgG) humoral immune responses against VSPs; however, only infected animals showed evident signs of giardiasis. This is the first comprehensive report of cytokine expression and anti- Giardia antibody production during infection and VSP vaccination in gerbils, a reliable model of the human disease. Copyright © 2018 American Society for Microbiology.

  4. Characterization of RNase MRP RNA and novel snoRNAs from Giardia intestinalis and Trichomonas vaginalis

    Science.gov (United States)

    2011-01-01

    Background Eukaryotic cells possess a complex network of RNA machineries which function in RNA-processing and cellular regulation which includes transcription, translation, silencing, editing and epigenetic control. Studies of model organisms have shown that many ncRNAs of the RNA-infrastructure are highly conserved, but little is known from non-model protists. In this study we have conducted a genome-scale survey of medium-length ncRNAs from the protozoan parasites Giardia intestinalis and Trichomonas vaginalis. Results We have identified the previously 'missing' Giardia RNase MRP RNA, which is a key ribozyme involved in pre-rRNA processing. We have also uncovered 18 new H/ACA box snoRNAs, expanding our knowledge of the H/ACA family of snoRNAs. Conclusions Results indicate that Giardia intestinalis and Trichomonas vaginalis, like their distant multicellular relatives, contain a rich infrastructure of RNA-based processing. From here we can investigate the evolution of RNA processing networks in eukaryotes. PMID:22053856

  5. Molecular characterization of Giardia intestinalis assemblage E from goat kids in Bangladesh

    Directory of Open Access Journals (Sweden)

    Mohammad Alamgir Hossain

    2015-05-01

    Full Text Available Objective: To molecularly characterize Giardia in goat kids to elucidate the possible zoonotic hazards in Bangladesh and find out the role of Giardia protozoan parasite as a source of human infection. Methods: Fecal samples of 100 goat kids were genotyped by nested PCR amplification of β-giardin gene fragment followed by sequencing and analysis. Results: The total prevalence of Giardia in goat kids was 3% (3/100 and the infection is more widespread in younger (P = 0.36, Black Bengal breed (P = 0.81 and female goat kids (P = 0.58. Further analysis ofβ-giardin gene locus has shown that the gene clustered in assemblage E rather than assemblages A and B. Conclusions: The present study suggests the low zoonotic transmission frequency from the goat kids and and giardiasis has least epidemiological significance to humans. Further study on this field is prerequisite in terms of broad geographical areas, age groups, sex and evaluation of zoonotic significance along with genetic diversity in other host species as well.

  6. A study on protozoan infections (Giardia, Entamoeba, Isoapora and Cryptosporidium in stray dogs in Ilam province

    Directory of Open Access Journals (Sweden)

    S Kakekhani

    2011-11-01

    Full Text Available Giardia, Entamoeba, Isospora and Cryptosporidium are important protozoan parastites that caused diarrhea in human and animals. In the present study, fecal samples were collected fresh, directly from the rectum of 112 stray dogs in Ilam province. Giardia and Entamoeba were concentrated by using the formalin ether sedimentation method followed by the trichrome and iodine staining technique andCryptosporidium  oocysts  were  concentrated  by  using  the  formalin  ether  sedimentation  method  followed by the modified Ziehl-Neelsen staining technique. Of 112 stray dogs, protozoan infections were detected from feces of 46 dogs (41.07% that Giardia infection was detected from feces of 21 dogs (18.75%, Isospora 17 (15.17%, Cryptosporidium 8 (7.14% and synchronization infection to 2 protozoan in 9 dogs (8.03% and to 3 protozoan in 3 (2.67%. In the present study not observed to Entamoeba. No statistically significant differences in prevalence of protozoan parasites occurred between female (34.21 % and male (55.5 % stray dogs (p>0/05. But statistically significant differences in prevalence occurred between 1≥0 and 0 ≥1 stray dogs (p>0/05. So that stray dogs of Ilam province can cause infection of human water and food sources.

  7. Characterization of RNase MRP RNA and novel snoRNAs from Giardia intestinalis and Trichomonas vaginalis

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    Chen Xiaowei S

    2011-11-01

    Full Text Available Abstract Background Eukaryotic cells possess a complex network of RNA machineries which function in RNA-processing and cellular regulation which includes transcription, translation, silencing, editing and epigenetic control. Studies of model organisms have shown that many ncRNAs of the RNA-infrastructure are highly conserved, but little is known from non-model protists. In this study we have conducted a genome-scale survey of medium-length ncRNAs from the protozoan parasites Giardia intestinalis and Trichomonas vaginalis. Results We have identified the previously 'missing' Giardia RNase MRP RNA, which is a key ribozyme involved in pre-rRNA processing. We have also uncovered 18 new H/ACA box snoRNAs, expanding our knowledge of the H/ACA family of snoRNAs. Conclusions Results indicate that Giardia intestinalis and Trichomonas vaginalis, like their distant multicellular relatives, contain a rich infrastructure of RNA-based processing. From here we can investigate the evolution of RNA processing networks in eukaryotes.

  8. Molecular characterization of Cryptosporidium and Giardia in farmers and their ruminant livestock from the Coastal Savannah zone of Ghana.

    Science.gov (United States)

    Squire, Sylvia Afriyie; Yang, Rongchang; Robertson, Ian; Ayi, Irene; Ryan, Una

    2017-11-01

    Cryptosporidium and Giardia are major causes of diarrhoea in developing countries including Ghana, however, nothing is known about the species and subtypes of Cryptosporidium and Giardia in farmers and their ruminant livestock in this country. A total of 925 faecal samples from humans (n=95), cattle (n=328), sheep (n=217) and goats (n=285), were screened for Cryptosporidium and Giardia by quantitative PCR (qPCR) at the 18S rRNA and glutamate dehydrogenase (gdh) loci respectively. Cryptosporidium positives were typed by sequence analysis of 18S and 60kDa glycoprotein (gp60) loci amplicons. Giardia positives were typed at the triose phosphate isomerase (tpi), beta-giardin (bg) and gdh loci. The prevalence of Cryptosporidium and Giardia by qPCR was 8.4% and 10.5% in humans, 26.5% and 8.5% in cattle, 34.1% and 12.9% in sheep, and 33.3% and 12.3% in goat faecal samples, respectively. G. duodenalis assemblages A and B were detected in humans and assemblage E was detected in livestock. Cryptosporidium parvum was the only species identified in humans; C. andersoni, C. bovis, C. ryanae and C. ubiquitum were identified in cattle; C. xiaoi, C. ubiquitum and C. bovis in sheep; and C. xiaoi, C. baileyi and C. parvum in goats. This is the first molecular study of Cryptosporidium and Giardia in livestock in Ghana. The identification of zoonotic species and the identification of C. parvum subtype IIcA5G3q in livestock, which has previously been identified in children in Ghana, suggests potential zoonotic transmission. Further studies on larger numbers of human and animal samples, and on younger livestock are required to better understand the epidemiology and transmission of Cryptosporidium and Giardia in Ghana. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Occurrence of Cryptosporidium spp. and Giardia spp. in a public water-treatment system, Paraná, Southern Brazil

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    Jonatas Campos Almeida

    Full Text Available The purpose of this study was to investigate the occurrence of Cryptosporidium spp. and Giardia spp. in a public water-treatment system. Samples of raw and treated water were collected and concentrated using the membrane filtration technique. Direct Immunofluorescence Test was performed on the samples. DNA extraction using a commercial kit was performed and the DNA extracted was submitted to a nested-PCR reaction (n-PCR and sequencing. In the immunofluorescence, 2/24 (8.33% samples of raw water were positive for Giardia spp.. In n-PCR and sequencing, 2/24 (8.33% samples of raw water were positive for Giardia spp., and 2/24 (8.33% samples were positive for Cryptosporidium spp.. The sequencing showed Cryptosporidium parvum and Giardia duodenalis DNA. In raw water, there was moderate correlation among turbidity, color and Cryptosporidium spp. and between turbidity and Giardia spp.. The presence of these protozoans in the water indicates the need for monitoring for water-treatment companies.

  10. Intestinal infection with Giardia spp. reduces epithelial barrier function in a myosin light chain kinase-dependent fashion.

    Science.gov (United States)

    Scott, Kevin G-E; Meddings, Jonathon B; Kirk, David R; Lees-Miller, Susan P; Buret, André G

    2002-10-01

    Giardiasis causes malabsorptive diarrhea, and symptoms can be present in the absence of any significant morphologic injury to the intestinal mucosa. The effects of giardiasis on epithelial permeability in vivo remain unknown, and the role of T cells and myosin light chain kinase (MLCK) in altered intestinal barrier function is unclear. This study was conducted to determine whether Giardia spp. alters intestinal permeability in vivo, to assess whether these abnormalities are dependent on T cells, and to assess the role of MLCK in altered epithelial barrier function. Immunocompetent and isogenic athymic mice were inoculated with axenic Giardia muris trophozoites or sterile vehicle (control), then assessed for trophozoite colonization and gastrointestinal permeability. Mechanistic studies using nontransformed human duodenal epithelial monolayers (SCBN) determined the effects of Giardia on myosin light chain (MLC) phosphorylation, transepithelial fluorescein isothiocyanate-dextran fluxes, cytoskeletal F-actin, tight junctional zonula occludens-1 (ZO-1), and MLCK. Giardia infection caused a significant increase in small intestinal, but not gastric or colonic, permeability that correlated with trophozoite colonization in both immunocompetent and athymic mice. In vitro, Giardia increased permeability and phosphorylation of MLC and reorganized F-actin and ZO-1. These alterations were abolished with an MLCK inhibitor. Disruption of small intestinal barrier function is T cell independent, disappears on parasite clearance, and correlates with reorganization of cytoskeletal F-actin and tight junctional ZO-1 in an MLCK-dependent fashion.

  11. Prevalence of Giardia and Cryptosporidium in beef cows in southern Ontario and in beef calves in southern British Columbia.

    Science.gov (United States)

    McAllister, Tim A; Olson, Merle E; Fletch, Andy; Wetzstein, Merv; Entz, Toby

    2005-01-01

    In 1998 and 1999, fecal samples were collected from 669 beef cows on 39 farms located within 10 counties of Ontario. Overall prevalences of Giardia, Cryptosporidium muris, and Cryptosporidium parvum in cows were 8.7%, 10.6%, and 18.4%, respectively. Of the 39 farms sampled, Giardia was detected on 64%, Cr. muris on 72%, and Cr. parvum on 90%. Cryptosporidium parvum was detected in 28% of the cows in 1998 and in 5.2% in 1999. Differences between the 2 y were attributed to sampling during calving in 1998 and during gestation in 1999. In 1998, Giardia, Cr. muris, and Cr. parvum were detected in herds provided with municipal water. In 1998, 193 calves were sampled from 10 farms, representing 4 watersheds, in British Columbia. Thirty-six percent of the calves exhibited signs of diarrhea. Overall prevalences of Giardia and Cryptosporidium spp. in calves were 36% and 13%, respectively. There was evidence that calves with Giardia were more likely to develop scours. Restricting cattle from surface water during periods of high shedding may reduce watershed contamination.

  12. Prevalence and molecular characterization of Cryptosporidum spp. and Giardia spp. in environmental samples in Hanam province, Vietnam

    DEFF Research Database (Denmark)

    Nguyen, Tram Thuy; Traub, Rebecca J.; Pham, Phuc Duc

    2016-01-01

    Cryptosporidium and Giardia are protozoan parasites that cause human diarrheal disease worldwide. This study was done to evaluate the prevalence and concentrations of these protozoa in environmental samples in Hanam, Vietnam and to assess potential contamination sources using molecular...... Giardia and Cryptosporidium were detected in 25.4% and 35.0% of samples analyzed, respectively. In water, a higher percentage of Cryptosporidium spp. (41.7%; 43/103) contamination was observed compared to that of Giardia spp. 28.2% (29/103). Both Giardia spp. and Cryptosporidium spp. were found...... contaminating vegetables at the same level, at 15.4% (4/26) each. Concentrations of Cryptosporidium in samples ranged from 10 to 1900 oocysts per 100 ml water or 100 g vegetable/composted waste sample with a median number of 100 oocysts per 100 ml/g. The concentration of Giardia cysts ranged from 10 to 1836 per...

  13. Debaryomyces hansenii: A Model System for Marine Molecular Biology

    Science.gov (United States)

    1991-12-31

    bisexualts and Ochromonas danica (Gunderson et al. 1987), Prorocerarum micans (Herzog and Maroteaux, 1986), Crypthecodinium cohnii and Saccocystis muris ...Dicdyostelium discoideum(McCaroll et al. 1983), Physarum polycephatun (Johansen et al. 1988), Giardia lamblia (Sogin et al. 1989), Suijflobus...Physanum polycephalum , Giardia lamblia , and .ulfolobu soljbnicus used as outgroups). The relationships of the ciliates, the apicomplexans, and the

  14. Giardia duodenalis and Cryptosporidium occurrence in Australian sea lions (Neophoca cinerea) exposed to varied levels of human interaction.

    Science.gov (United States)

    Delport, Tiffany C; Asher, Amy J; Beaumont, Linda J; Webster, Koa N; Harcourt, Robert G; Power, Michelle L

    2014-12-01

    Giardia and Cryptosporidium are amongst the most common protozoan parasites identified as causing enteric disease in pinnipeds. A number of Giardia assemblages and Cryptosporidium species and genotypes are common in humans and terrestrial mammals and have also been identified in marine mammals. To investigate the occurrence of these parasites in an endangered marine mammal, the Australian sea lion (Neophoca cinerea), genomic DNA was extracted from faecal samples collected from wild populations (n = 271) in Southern and Western Australia and three Australian captive populations (n = 19). These were screened using PCR targeting the 18S rRNA of Giardia and Cryptosporidium. Giardia duodenalis was detected in 28 wild sea lions and in seven captive individuals. Successful sequencing of the 18S rRNA gene assigned 27 Giardia isolates to assemblage B and one to assemblage A, both assemblages commonly found in humans. Subsequent screening at the gdh and β-giardin loci resulted in amplification of only one of the 35 18S rRNA positive samples at the β-giardin locus. Sequencing at the β-giardin locus assigned the assemblage B 18S rRNA confirmed isolate to assemblage AI. The geographic distribution of sea lion populations sampled in relation to human settlements indicated that Giardia presence in sea lions was highest in populations less than 25 km from humans. Cryptosporidium was not detected by PCR screening in either wild colonies or captive sea lion populations. These data suggest that the presence of G. duodenalis in the endangered Australian sea lion is likely the result of dispersal from human sources. Multilocus molecular analyses are essential for the determination of G. duodenalis assemblages and subsequent inferences on transmission routes to endangered marine mammal populations.

  15. Estimating Cryptosporidium and Giardia disease burdens for children drinking untreated groundwater in a rural population in India.

    Science.gov (United States)

    Daniels, Miles E; Smith, Woutrina A; Jenkins, Marion W

    2018-01-01

    In many low-income settings, despite improvements in sanitation and hygiene, groundwater sources used for drinking may be contaminated with enteric pathogens such as Cryptosporidium and Giardia, which remain important causes of childhood morbidity. In this study, we examined the contribution of diarrhea caused by Cryptosporidium and Giardia found in groundwater sources used for drinking to the total burden of diarrheal disease among children cause (i.e., all fecal-oral enteric pathogens and exposure pathways) child diarrhea prevalence rates observed in the study population during two monsoon seasons (2012 and 2013). We used site specific and regional studies to inform assumptions about the human pathogenicity of the Cryptosporidium and Giardia species present in local groundwater. In all three human pathogenicity scenarios evaluated, the mean daily risk of Cryptosporidium or Giardia infection (0.06-1.53%), far exceeded the tolerable daily risk of infection from drinking water in the US (water was as high as 6.5% or as low as cause diarrhea disease burden measured in children causing diarrhea than did Giardia. Diarrhea prevalence estimates for waterborne Cryptosporidium infection appeared to be most sensitive to assumptions about the probability of infection from ingesting a single parasite (i.e. the rate parameter in dose-response model), while Giardia infection was most sensitive to assumptions about the viability of parasites detected in groundwater samples. Protozoa in groundwater drinking sources in rural India, even at low concentrations, especially for Cryptosporidium, may account for a significant portion of child diarrhea morbidity in settings were tubewells are used for drinking water and should be more systematically monitored. Preventing diarrheal disease burdens in Puri District and similar settings will benefit from ensuring water is microbiologically safe for consumption and consistent and effective household water treatment is practiced.

  16. Giardia duodenalis and Cryptosporidium occurrence in Australian sea lions (Neophoca cinerea exposed to varied levels of human interaction

    Directory of Open Access Journals (Sweden)

    Tiffany C. Delport

    2014-12-01

    Full Text Available Giardia and Cryptosporidium are amongst the most common protozoan parasites identified as causing enteric disease in pinnipeds. A number of Giardia assemblages and Cryptosporidium species and genotypes are common in humans and terrestrial mammals and have also been identified in marine mammals. To investigate the occurrence of these parasites in an endangered marine mammal, the Australian sea lion (Neophoca cinerea, genomic DNA was extracted from faecal samples collected from wild populations (n = 271 in Southern and Western Australia and three Australian captive populations (n = 19. These were screened using PCR targeting the 18S rRNA of Giardia and Cryptosporidium. Giardia duodenalis was detected in 28 wild sea lions and in seven captive individuals. Successful sequencing of the 18S rRNA gene assigned 27 Giardia isolates to assemblage B and one to assemblage A, both assemblages commonly found in humans. Subsequent screening at the gdh and β-giardin loci resulted in amplification of only one of the 35 18S rRNA positive samples at the β-giardin locus. Sequencing at the β-giardin locus assigned the assemblage B 18S rRNA confirmed isolate to assemblage AI. The geographic distribution of sea lion populations sampled in relation to human settlements indicated that Giardia presence in sea lions was highest in populations less than 25 km from humans. Cryptosporidium was not detected by PCR screening in either wild colonies or captive sea lion populations. These data suggest that the presence of G. duodenalis in the endangered Australian sea lion is likely the result of dispersal from human sources. Multilocus molecular analyses are essential for the determination of G. duodenalis assemblages and subsequent inferences on transmission routes to endangered marine mammal populations.

  17. Estimating Cryptosporidium and Giardia disease burdens for children drinking untreated groundwater in a rural population in India.

    Directory of Open Access Journals (Sweden)

    Miles E Daniels

    2018-01-01

    Full Text Available In many low-income settings, despite improvements in sanitation and hygiene, groundwater sources used for drinking may be contaminated with enteric pathogens such as Cryptosporidium and Giardia, which remain important causes of childhood morbidity. In this study, we examined the contribution of diarrhea caused by Cryptosporidium and Giardia found in groundwater sources used for drinking to the total burden of diarrheal disease among children < 5 in rural India.We studied a population of 3,385 children < 5 years of age in 100 communities of Puri District, Odisha, India. We developed a coupled quantitative microbial risk assessment (QMRA and susceptible-infected-recovered (SIR population model based on observed levels of Cryptosporidium and Giardia in improved groundwater sources used for drinking and compared the QMRA-SIR estimates with independently measured all-cause (i.e., all fecal-oral enteric pathogens and exposure pathways child diarrhea prevalence rates observed in the study population during two monsoon seasons (2012 and 2013. We used site specific and regional studies to inform assumptions about the human pathogenicity of the Cryptosporidium and Giardia species present in local groundwater. In all three human pathogenicity scenarios evaluated, the mean daily risk of Cryptosporidium or Giardia infection (0.06-1.53%, far exceeded the tolerable daily risk of infection from drinking water in the US (< 0.0001%. Depending on which protozoa species were present, median estimates of daily child diarrhea prevalence due to either Cryptosporidium or Giardia infection from drinking water was as high as 6.5% or as low as < 1% and accounted for at least 2.9% and as much as 65.8% of the all-cause diarrhea disease burden measured in children < 5 during the study period. Cryptosporidium tended to account for a greater share of estimated waterborne protozoa infections causing diarrhea than did Giardia. Diarrhea prevalence estimates for waterborne

  18. Molecular characterization of Giardia duodenalis cysts in the Oreto River (Sicily, Southern Italy

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    Maria Antonella Di Benedetto

    2010-03-01

    Full Text Available

    Background: The presence of Giardia was investigated along the Oreto river between January 2008 and May 2009 with the aim of understanding the source of contamination by molecular typing of cysts.

    Methods: A total of 38 water samples (10 collected from the river mouth, 24 from the whole Oreto basin and 4 sewage samples from the Monreale treatment plant were processed. In addition, 22 faecal samples of livestock living close to the Oreto area, were analyzed. The presence of Giardia was determined by immunofluorescence assay and their genetic characterization was achieved by a nested PCR assay targeting the triosephosphate isomerase gene.

    Results: All water samples from the river mouth were positive for Giardia, even if the concentration of cysts fluctuated considerably among sampling occasions. Our investigation showed that the Vadduneddu and Altofonte torrents, two influents of the river, were the principal sources of contamination. Moreover, the genotypes of Vadduneddu torrent were the same as those detected in human wastewater taken from the activated sludge plant of Monreale city. Assemblages A and B were found in water samples with a predominance of Assemblage A, subtype AII. Assemblage E was only found in a single calf isolate.

    Conclusions: The data show that the high cyst counts regularly detected in the Oreto river are due to contamination with wastewater of human origin. This finding is relevant for public health, particularly because river water is used for agricultural purposes.

  19. Severity of Giardia infection associated with post-infectious fatigue and abdominal symptoms two years after

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    Rortveit Guri

    2009-12-01

    Full Text Available Abstract Background A high rate of post-infectious fatigue and abdominal symptoms two years after a waterborne outbreak of giardiasis in Bergen, Norway in 2004 has previously been reported. The aim of this report was to identify risk factors associated with such manifestations. Methods All laboratory confirmed cases of giardiasis (n = 1262 during the outbreak in Bergen in 2004 received a postal questionnaire two years after. Degree of post-infectious abdominal symptoms and fatigue, as well as previous abdominal problems, was recorded. In the statistical analyses number of treatment courses, treatment refractory infection, delayed education and sick leave were used as indices of protracted and severe Giardia infection. Age, gender, previous abdominal problems and symptoms during infection were also analysed as possible risk factors. Simple and multiple ordinal logistic regression models were used for the analyses. Results The response rate was 81% (1017/1262, 64% were women and median age was 31 years (range 3-93, compared to 61% women and 30 years (range 2-93 among all 1262 cases. Factors in multiple regression analysis significantly associated with abdominal symptoms two years after infection were: More than one treatment course, treatment refractory infection, delayed education, bloating and female gender. Abdominal problems prior to Giardia infection were not associated with post-infectious abdominal symptoms. More than one treatment course, delayed education, sick leave more than 2 weeks, and malaise at the time of infection, were significantly associated with fatigue in the multiple regression analysis, as were increasing age and previous abdominal problems. Conclusion Protracted and severe giardiasis seemed to be a risk factor for post-infectious fatigue and abdominal symptoms two years after clearing the Giardia infection.

  20. A PCR procedure for the detection of Giardia intestinalis cysts and Escherichia coli in lettuce.

    Science.gov (United States)

    Ramirez-Martinez, M L; Olmos-Ortiz, L M; Barajas-Mendiola, M A; Giono Cerezo, S; Avila, E E; Cuellar-Mata, P

    2015-06-01

    Giardia intestinalis is a pathogen associated with foodborne outbreaks and Escherichia coli is commonly used as a marker of faecal contamination. Implementation of routine identification methods of G. intestinalis is difficult for the analysis of vegetables and the microbiological detection of E. coli requires several days. This study proposes a PCR-based assay for the detection of E. coli and G. intestinalis cysts using crude DNA isolated from artificially contaminated lettuce. The G. intestinalis and E. coli PCR assays targeted the β-giardin and uidA genes, respectively, and were 100% specific. Forty lettuces from local markets were analysed by both PCR and light microscopy and no cysts were detected, the calculated detection limit was 20 cysts per gram of lettuce; however, by PCR, E. coli was detected in eight of ten randomly selected samples of lettuce. These data highlight the need to validate procedures for routine quality assurance. These PCR-based assays can be employed as alternative methods for the detection of G. intestinalis and E. coli and have the potential to allow for the automation and simultaneous detection of protozoa and bacterial pathogens in multiple samples. Significance and impact of the study: There are few studies for Giardia intestinalis detection in food because methods for its identification are difficult for routine implementation. Here, we developed a PCR-based method as an alternative to the direct observation of cysts in lettuce by light microscopy. Additionally, Escherichia coli was detected by PCR and the sanitary quality of lettuce was evaluated using molecular and standard microbiological methods. Using PCR, the detection probability of Giardia cysts inoculated onto samples of lettuce was improved compared to light microscopy, with the advantage of easy automation. These methods may be employed to perform timely and affordable detection of foodborne pathogens. © 2015 The Society for Applied Microbiology.

  1. Novel structural components of the ventral disc and lateral crest in Giardia intestinalis.

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    Kari D Hagen

    2011-12-01

    Full Text Available Giardia intestinalis is a ubiquitous parasitic protist that is the causative agent of giardiasis, one of the most common protozoan diarrheal diseases in the world. Giardia trophozoites attach to the intestinal epithelium using a specialized and elaborate microtubule structure, the ventral disc. Surrounding the ventral disc is a less characterized putatively contractile structure, the lateral crest, which forms a continuous perimeter seal with the substrate. A better understanding of ventral disc and lateral crest structure, conformational dynamics, and biogenesis is critical for understanding the mechanism of giardial attachment to the host. To determine the components comprising the ventral disc and lateral crest, we used shotgun proteomics to identify proteins in a preparation of isolated ventral discs. Candidate disc-associated proteins, or DAPs, were GFP-tagged using a ligation-independent high-throughput cloning method. Based on disc localization, we identified eighteen novel DAPs, which more than doubles the number of known disc-associated proteins. Ten of the novel DAPs are associated with the lateral crest or outer edge of the disc, and are the first confirmed components of this structure. Using Fluorescence Recovery After Photobleaching (FRAP with representative novel DAP::GFP strains we found that the newly identified DAPs tested did not recover after photobleaching and are therefore structural components of the ventral disc or lateral crest. Functional analyses of the novel DAPs will be central toward understanding the mechanism of ventral disc-mediated attachment and the mechanism of disc biogenesis during cell division. Since attachment of Giardia to the intestine via the ventral disc is essential for pathogenesis, it is possible that some proteins comprising the disc could be potential drug targets if their loss or disruption interfered with disc biogenesis or function, preventing attachment.

  2. Occurrence of Giardia cysts and Cryptosporidium oocysts in activated sludge samples in Campinas, SP, Brazil.

    Science.gov (United States)

    Santos, Luciana Urbano; Bonatti, Taís Rondello; Cantusio Neto, Romeu; Franco, Regina Maura Bueno

    2004-01-01

    Giardia and Cryptosporidium have caused several outbreaks of gastroenteritis in humans associated with drinking water. Contaminated sewage effluents are recognized as a potential source of waterborne protozoa. Due to the lack of studies about the occurrence of these parasites in sewage samples in Brazil, we compared the efficiency of two procedures for concentrating cysts and oocysts in activated sludge samples of one sewage treatment plant. For this, the samples were submitted to i) concentration by the ether clarification procedure (ECP) and to ii) purification by sucrose flotation method (SFM) and aliquots of the pellets were examined by immunofluorescence. Giardia cysts were present in all samples (100.0%; n = 8) when using ECP and kit 1 reagents, while kit 2 resulted in six positive samples (85.7%; n = 7). As for SFM, cysts were detected in 75.0% and 100.0% of these samples (for kit 1 and 2, respectively). Regarding Cryptosporidium, two samples (25.0%; kit 1 and 28.5% for kit 2) were detected positive by using ECP, while for SFM, only one sample (examined by kit 1) was positive (12.5%). The results of the control trial revealed Giardia and Cryptosporidium recovery efficiency rates for ECP of 54.5% and 9.6%, while SFM was 10.5% and 3.2%, respectively. Considering the high concentration detected, a previous evaluation of the activated sludge before its application in agriculture is recommended and with some improvement, ECP would be an appropriate simple technique for protozoa detection in sewage samples.

  3. Evidence of heterozygosity and recombinant alleles in single cysts of Giardia duodenalis

    OpenAIRE

    Aguiar, Juliana Martins; Silva, Sheila Oliveira; Santos, Valdir Azevedo dos; Taniwaki, Sueli Akemi; Oliveira, Tricia Maria Ferreira de Sousa; Ferreira, Helena Lage; Keid, Lara Borges; Gregori, Fábio; Soares, Rodrigo Martins

    2016-01-01

    Abstract Giardia duodenalis is divided into eight assemblages (named A to H). Isolates of assemblage A are divided into four sub-assemblages (AI, AII, AIII and AIV). While isolates of sub-assemblage AII are almost exclusively detected in human hosts, isolates of assemblage B are encountered in a multitude of animal hosts and humans. Here, we isolated single cysts of G. duodenalis from a human stool sample and found that one of them had overlaps of assemblage AII and B alleles and an unexpecte...

  4. Potential role of beavers (Castor fiber in contamination of water in the Masurian Lake District (north-eastern Poland with protozoan parasites Cryptosporidium spp. and Giardia duodenalis

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    Sroka Jacek

    2015-06-01

    Full Text Available The purpose of this study was to assess the possible influence of beavers on the contamination of lake water with zoonotic parasites Giardia duodenalis and Cryptosporidium spp., with respect to the risk to human health. A total of 79 water samples were taken around the habitats of beavers from 14 localities situated in the recreational Masurian Lake District (north-eastern Poland. Water was sampled in the spring and autumn seasons, at different distances from beavers’ lodges (0-2, 10, 30, and 50 m. The samples were examined for the presence of (oocysts of zoonotic protozoa Giardia duodenalis and Cryptosporidium spp. by direct fluorescence assay (DFA and by nested and real time PCR. By DFA, the presence of Giardia cysts was found in 36 samples (45.6% and the presence of Cryptosporidium oocysts in 26 samples (32.9%. Numbers of Giardia cysts, Cryptosporidium oocysts, and summarised (oocysts of both parasites showed a significant variation depending on locality. The numbers of Giardia cysts significantly decreased with the distance from beavers’ lodges while the numbers of Cryptosporidium oocysts did not show such dependence. The amount of Giardia cysts in samples collected in spring was approximately 3 times higher than in autumn. Conversely, a larger number of Cryptosporidium oocysts were detected in samples collected in autumn than in spring. By PCR, Giardia DNA was found in 38 samples (48.1% whereas DNA of Cryptosporidium was found in only 7 samples (8.9%. Eleven Giardia isolates were subjected to phylogenetic analysis by restriction fragment length polymorphism PCR or sequencing which evidenced their belonging to zoonotic assemblages: A (3 isolates and B (8 isolates. In conclusion, water in the vicinity of beavers’ lodges in the tested region was markedly contaminated with (oocysts of Giardia duodenalis and Cryptosporidium spp., which confirms the potential role of beavers as a reservoir of these parasites and indicates a need for

  5. Identification and molecular characterization of Cryptosporidium and Giardia in children and cattle populations from the province of Alava, North of Spain

    Energy Technology Data Exchange (ETDEWEB)

    Cardona, Guillermo A. [Livestock Laboratory, Regional Government of Alava, Ctra. de Azua 4, 01520 Vitoria-Gasteiz (Spain); Carabin, Helene [Department of Biostatistics and Epidemiology, College of Public Health, Oklahoma University Health Sciences Center, 801 Northeast 13th Street, Room 309, Oklahoma City, OK 73104 (United States); Goni, Pilar [Department of Microbiology, Preventive Medicine and Public Health, Faculty of Medicine, University of Zaragoza, Domingo Miral s/n, 50009 Zaragoza (Spain); Arriola, Larraitz [Epidemiology Unit, Public Health Division of Guipuzcoa, Basque Government, Av. Navarra 4, 2013 San Sebastian (Spain); Robinson, Guy [UK Cryptosporidium Reference Unit, Public Health Wales, Microbiology ABM, Swansea, Singleton Hospital, Swansea SA2 8QA (United Kingdom); Fernandez-Crespo, Juan C. [Sub-direction of Public Health of Alava, Department of Health, Basque Government, Avda. Santiago 11, 01002 Vitoria-Gasteiz (Spain); Clavel, Antonio [Department of Microbiology, Preventive Medicine and Public Health, Faculty of Medicine, University of Zaragoza, Domingo Miral s/n, 50009 Zaragoza (Spain); Chalmers, Rachel M. [UK Cryptosporidium Reference Unit, Public Health Wales, Microbiology ABM, Swansea, Singleton Hospital, Swansea SA2 8QA (United Kingdom); Carmena, David, E-mail: d.carmena@imperial.ac.uk [MRC Clinical Sciences Centre, Faculty of Medicine, Imperial College, Hammersmith Hospital Campus, Du Cane Road, London W12 0NN (United Kingdom)

    2011-12-15

    The prevalence of and factors associated with the protozoan enteropathogens Cryptosporidium and Giardia have been investigated in selected children and cattle populations from the province of Alava (Northern Spain). The presence of these organisms was detected in fecal samples using commercially available coproantigen-ELISA (CpAg-ELISA) and immunochromatographic (ICT) assays. A total of 327 caregivers of children participants were asked to answer questions on risk factors potentially associated to the prevalence of Cryptosporidium and Giardia, including water-use practices, water sports and contact with domestic or pet animals. Molecular analyses were conducted using a nested-PCR technique to amplify the small-subunit (SSU) rRNA gene of Cryptosporidium and the triosephosphate isomerase (tpi) gene of Giardia. Cryptosporidium oocysts and Giardia cysts were found in 3 and 16 samples using the CpAg-ELISA, and in 5 and 9 samples using the ICT test, respectively. Cryptosporidium and Giardia were also found in 7 and 17 samples by CpAg-ELISA, and 4 and 14 samples by ICT, respectively, of 227 cattle fecal samples. The overall Cryptosporidium and Giardia infection prevalences, based on a Bayesian approach accounting for the imperfect sensitivities and specificities of both diagnostic tests, were estimated to 1.0% (95% BCI: 0.2%-2.8%) and 3.1% (1.5%-5.3%) in children and 3.0% (0.5%-9.2%) and 1.4% (0.0%-6.4%) in cattle, respectively. In humans, a single Cryptosporidium isolate was characterized as C. hominis. Of seven Giardia isolates, four were identified as assemblage B, two as assemblage A-II and one was a mixed assemblage B + A-II infection. No Cryptosporidium or Giardia isolates could be obtained from cattle samples. Although limited, these results seem to suggest that cattle are unlikely to be an important reservoir of zoonotic Cryptosporidium and/or Giardia in the province of Alava.

  6. Giardia co-infection promotes the secretion of antimicrobial peptides beta-defensin 2 and trefoil factor 3 and attenuates attaching and effacing bacteria-induced intestinal disease.

    Science.gov (United States)

    Manko, Anna; Motta, Jean-Paul; Cotton, James A; Feener, Troy; Oyeyemi, Ayodele; Vallance, Bruce A; Wallace, John L; Buret, Andre G

    2017-01-01

    Our understanding of polymicrobial gastrointestinal infections and their effects on host biology remains incompletely understood. Giardia duodenalis is an ubiquitous intestinal protozoan parasite infecting animals and humans. Concomitant infections with Giardia and other gastrointestinal pathogens commonly occur. In countries with poor sanitation, Giardia infection has been associated with decreased incidence of diarrheal disease and fever, and reduced serum inflammatory markers release, via mechanisms that remain obscure. This study analyzed Giardia spp. co-infections with attaching and effacing (A/E) pathogens, and assessed whether and how the presence of Giardia modulates host responses to A/E enteropathogens, and alters intestinal disease outcome. In mice infected with the A/E pathogen Citrobacter rodentium, co-infection with Giardia muris significantly attenuated weight loss, macro- and microscopic signs of colitis, bacterial colonization and translocation, while concurrently enhancing the production and secretion of antimicrobial peptides (AMPs) mouse β-defensin 3 and trefoil factor 3 (TFF3). Co-infection of human intestinal epithelial cells (Caco-2) monolayers with G. duodenalis trophozoites and enteropathogenic Escherichia coli (EPEC) enhanced the production of the AMPs human β-defensin 2 (HBD-2) and TFF3; this effect was inhibited with treatment of G. duodenalis with cysteine protease inhibitors. Collectively, these results suggest that Giardia infections are capable of reducing enteropathogen-induced colitis while increasing production of host AMPs. Additional studies also demonstrated that Giardia was able to directly inhibit the growth of pathogenic bacteria. These results reveal novel mechanisms whereby Giardia may protect against gastrointestinal disease induced by a co-infecting A/E enteropathogen. Our findings shed new light on how microbial-microbial interactions in the gut may protect a host during concomitant infections.

  7. The presence of Giardia intestinalis in donkeys, Equus asinus, in China.

    Science.gov (United States)

    Zhang, Xiao-Xuan; Zhang, Fu-Kai; Li, Fa-Cai; Hou, Jun-Ling; Zheng, Wen-Bin; Du, Shuai-Zhi; Zhao, Quan; Zhu, Xing-Quan

    2017-01-03

    Giardia intestinalis is one of the most important zoonotic enteric parasites. As no information regarding prevalence and genotype of G. intestinalis in donkeys (Equus asinus) in China is available, 181 faecal samples from 48 donkeys from Jilin Province, from 104 from Shandong Province and from 29 from Liaoning Province were examined between May and December 2015. Twenty-eight (15.47%) out of 181 donkey samples were tested G. intestinalis-positive by nested amplification of the triosephosphate isomerase (tpi) gene. The prevalence in different regional groups varied from 10.42 to 18.27%. The prevalence in adult and young donkeys was 14.29 and 22.92%, respectively. Otherwise, the prevalence was 11.69% in summer and 18.27% in winter. However, no statistically significant differences were found in relation to region or age group. Sequence analysis of the tpi, glutamate dehydrogenase (gdh) and beta giardin (bg) loci identified 4, 1 and 3 subtypes of assemblage B, respectively. Moreover, four novel multilocus genotypes (MLGs novel-1 to novel-4) were identified in assemblage B. This first report of G. intestinalis in donkeys in China indicates that further studies of nation-wide molecular epidemiology and geographical distribution of Giardia in donkeys are warranted. Effective strategies should be implemented to control G. intestinalis infection in donkeys, other animals and humans.

  8. Reduction of Cryptosporidium, Giardia, and Fecal Indicators by Bardenpho Wastewater Treatment.

    Science.gov (United States)

    Schmitz, Bradley W; Moriyama, Hitoha; Haramoto, Eiji; Kitajima, Masaaki; Sherchan, Samendra; Gerba, Charles P; Pepper, Ian L

    2018-06-19

    Increased demand for water reuse and reclamation accentuates the importance for optimal wastewater treatment to limit protozoa in effluents. Two wastewater treatment plants utilizing advanced Bardenpho were investigated over a 12-month period to determine the incidence and reduction of Cryptosporidium, Giardia, Cyclospora, and fecal indicators. Results were compared to facilities that previously operated in the same geographical area. Protozoa (oo)cysts were concentrated using an electronegative filter and subsequently detected by fluorescent microscopy and/or PCR methods. Cryptosporidium and Giardia were frequently detected in raw sewage, but Cyclospora was not detected in any wastewater samples. Facilities with Bardenpho treatment exhibited higher removals of (oo)cysts than facilities utilizing activated sludge or trickling filters. This was likely due to Bardenpho systems having increased solid wasting rates; however, this mechanism cannot be confirmed as sludge samples were not analyzed. Use of dissolved-air-flotation instead of sedimentation tanks did not result in more efficient removal of (oo)cysts. Concentrations of protozoa were compared with each other, Escherichia coli, somatic coliphage, and viruses (pepper mild mottle virus, Aichi virus 1, adenovirus, and polyomaviruses JC and BK). Although significant correlations were rare, somatic coliphage showed the highest potential as an indicator for the abundance of protozoa in wastewaters.

  9. Plant species used in giardiasis treatment: ethnopharmacology and in vitro evaluation of anti-Giardia activity

    Directory of Open Access Journals (Sweden)

    Vanessa do A. Neiva

    Full Text Available The aim of this study was to compile the traditional knowledge about plants used for the treatment of giardiasis, and also to carry out experimental research to evaluate the anti-Giardia activity of five species.To reach this objective, 398 interviews were performed using a previously prepared questionnaire, followed by an in vitro evaluation of giardicidal potential of hydroalcoholic leaf extracts of Anacardium occidentale L., Chenopodium ambrosioides L., Passiflora edulis Sims, Psidium guajava L., and Stachytarpheta cayennensis(Rich. Vahl. Among the interviewed people, 55.53% reported the use of plants to treat diarrhea, the most severe symptom of giardiasis. The results indicated 36 species used by this population for these problems. The use of leaves (72.50% of a single plant (64.25% collected from backyards and gardens (44.34% and prepared by decoction were predominant. The majority of the interviewees (85.52% attributed their cure to the use of plants. In the experimental tests, all extracts inhibited the growth of Giardia lambliatrophozoites in different intensities: A. occidentale and P. guajava extracts elicited a moderate activity (250 ≤ IC50 ≤ 500 μg/ml, C. ambrosioides and S. cayennensis extracts evoked a high activity (100 ≤ IC50 ≤ 250 μg/ml, and P. edulis extract showed very high activity (IC50≤ 100 μg/ml. This study shows that an ethnopharmacological approach is useful in the selection of plant materials with potential giardicidal activity.

  10. Relative susceptibility of Giardia muris trophozoites to killing by mouse antibodies of different isotypes.

    Science.gov (United States)

    Heyworth, M F

    1992-02-01

    The aim of this work was to examine the ability of mouse IgA, IgG, and IgM anti-Giardia antibodies to kill Giardia muris trophozoites in the presence and absence of complement. Using a 2-color flow cytometry assay, binding of antibody to trophozoites was assessed with fluorescein-conjugated anti-mouse immunoglobulin, and percentages of killed trophozoites were quantified by staining with propidium iodide. Trophozoites were killed in the presence of complement by IgG3 and IgM anti-trophozoite monoclonal antibodies. Anti-trophozoite IgA, obtained from the intestinal lumen of G. muris-infected BALB/c mice, became bound to trophozoites in vitro but did not kill these organisms in the presence or absence of complement. The results suggest that clearance of G. muris infection by intestinal IgA directed against G. muris trophozoites does not involve antibody-dependent killing of trophozoites in the intestinal lumen.

  11. Reduction in fecal excretion of Giardia cysts: effect of cholestasis and diet.

    Science.gov (United States)

    Erlandsen, Stanley

    2005-12-01

    Bile is a major growth factor for the proliferation of Giardia spp. trophozoites in the small intestine and, at high concentrations, stimulates encystment of trophozoites. This report demonstrates that surgical cholestasis to interrupt the flow of bile from liver to intestine or the use of bile-binding resins in the diet can both dramatically decrease the fecal excretion of Giardia muris cysts. Cholestasis produced a 3 log reduction in excretion of G. muris cysts within 24 hr of surgery and a 4 log reduction after 3 days. Sham controls showed no difference in cyst excretion from presurgical control values. Two isocaloric diets were studied: a control diet (N) of Purina mouse chow containing 5% celufil and an experimental diet (CR) containing 5% cholestyramine, a resin that binds bile. Compared with the N diet, the CR diet was associated with reductions in cyst excretion of 3 logs within 1 day. Despite lowered excretion of G. muris cysts in mice fed the cholestyramine diet, the trophozoite recovery from the duodenum was similar with both diets. Cyclic feeding of the CR diet and the N diet at 3-day intervals produced significant oscillations (changes of 3-4 logs) in fecal cyst shedding. The significant reductions in fecal excretion of cysts observed with agents that bind bile suggests that diets capable of binding bile might be a therapeutic means to minimize the fecal excretion of cysts and thereby may help to reduce the risk of spreading giardiasis through fecal-oral contamination.

  12. Genetic diversity within the morphological species Giardia intestinalis and its relationship to host origin.

    Science.gov (United States)

    Monis, Paul T; Andrews, Ross H; Mayrhofer, Graham; Ey, Peter L

    2003-05-01

    A genetic analysis of Giardia intestinalis, a parasitic protozoan species that is ubiquitous in mammals worldwide, was undertaken using organisms derived from a variety of mammalian hosts in different geographical locations. The test panel of 53 Giardia isolates comprised 48 samples of G. intestinalis, including representatives of all known genetic subgroups, plus an isolate of G. ardeae and four isolates of G. muris. The isolates were compared by allozymic analysis of electrophoretic data obtained for 21 cytosolic enzymes, representing 23 gene loci. Neighbour Joining analysis of the allelic profiles supported the monophyly of G. intestinalis but showed that the species encompasses a rich population substructure. Seven major clusters were evident within G. intestinalis, corresponding to lineages designated previously as genetic assemblages A-G. Some genotypes, e.g. those defining assemblage A, are found in divergent host species and may be zoonotic. However other genotypes, e.g. those defining assemblages C-G, appear to be confined to particular hosts or host groups. The findings reinforce other evidence that G. intestinalis, which was defined on the basis of morphological criteria only, is a species complex.

  13. Nucleic acid stains as indicators of Giardia muris viability following cyst inactivation.

    Science.gov (United States)

    Taghi-Kilani, R; Gyürék, L L; Millard, P J; Finch, G R; Belosevic, M

    1996-06-01

    A reliable viability assay for Giardia is required for the development of disinfection process design criteria and pathogen monitoring by water treatment utilities. Surveys of single-staining nucleic acid dyes (stain dead parasites only), and double-staining vital dye kits from Molecular Probes (stain live and dead parasites) were conducted to assess the viability of untreated, heat-killed, and chemically inactivated Giardia muris cysts. Nucleic acid staining results were compared to those of in vitro excystation and animal infectivity. Nucleic acid stain, designated as SYTO-9, was considered the best among the single-staining dyes for its ability to stain dead cysts brightly and its relatively slow decay rate of visible light emission following DNA binding. SYTO-9 staining was correlated to animal infectivity. A Live/Dead BacLight was found to be the better of 2 double-staining viability kits tested. Logarithmic survival ratios based on SYTO-9 and Live/Dead BacLight were compared to excystation and infectivity results for G. muris cysts exposed to ozone or free chlorine. The results indicate that SYTO-9 and Live/Dead BacLight staining is stable following treatment of cysts with chemical disinfectants.

  14. Effect of initial microbial density on inactivation of Giardia muris by ozone.

    Science.gov (United States)

    Haas, Charles N; Kaymak, Baris

    2003-07-01

    Inactivation of microorganisms by disinfectants frequently shows non-linear behavior on a semilogarithmic plot of log survival ratio versus time. A number of models have been developed to depict these deviations from Chick's Law. Some of the models predict that the log survival ratio (at a particular disinfectant dose and contact time, even in absence of demand) would be a function of the initial concentration of microorganisms (N(0)), while other models do not predict such an effect. The effect of N(0) on the survival ratio has not been deliberately tested. This work examined the inactivation of Giardia muris by ozone in batch systems, deliberately varying the disinfectant dose and N(0). It was found that the models predicting a dependency of survival on N(0) gave a better description to the data than models that did not predict such a dependency. Hence there is an apparent decrease in disinfection efficiency of ozone against Giardia muris (at pH 8 and 15 degrees C) as the initial microorganism concentration decreases. This phenomena should be taken into account by both disinfection researchers and by process design engineers.

  15. Cryptosporidium,Giardia, Cryptococcus, Pneumocystis genetic variability: cryptic biological species or clonal near-clades?

    Directory of Open Access Journals (Sweden)

    Michel Tibayrenc

    2014-04-01

    Full Text Available An abundant literature dealing with the population genetics and taxonomy of Giardia duodenalis, Cryptosporidium spp., Pneumocystis spp., and Cryptococcus spp., pathogens of high medical and veterinary relevance, has been produced in recent years. We have analyzed these data in the light of new population genetic concepts dealing with predominant clonal evolution (PCE recently proposed by us. In spite of the considerable phylogenetic diversity that exists among these pathogens, we have found striking similarities among them. The two main PCE features described by us, namely highly significant linkage disequilibrium and near-clading (stable phylogenetic clustering clouded by occasional recombination, are clearly observed in Cryptococcus and Giardia, and more limited indication of them is also present in Cryptosporidium and Pneumocystis. Moreover, in several cases, these features still obtain when the near-clades that subdivide the species are analyzed separately ("Russian doll pattern". Lastly, several sets of data undermine the notion that certain microbes form clonal lineages simply owing to a lack of opportunity to outcross due to low transmission rates leading to lack of multiclonal infections ("starving sex hypothesis". We propose that the divergent taxonomic and population genetic inferences advanced by various authors about these pathogens may not correspond to true evolutionary differences and could be, rather, the reflection of idiosyncratic practices among compartmentalized scientific communities. The PCE model provides an opportunity to revise the taxonomy and applied research dealing with these pathogens and others, such as viruses, bacteria, parasitic protozoa, and fungi.

  16. Molecular identification of Giardia duodenalis in Ecuador by polymerase chain reaction-restriction fragment length polymorphism

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    Richard Atherton

    2013-06-01

    Full Text Available The aim of this study was to determine the genetic diversity of Giardia duodenalis present in a human population living in a northern Ecuadorian rain forest. All Giardia positive samples (based on an ELISA assay were analysed using a semi-nested polymerase chain reaction-restriction fragment length polymorphism assay that targets the glutamate dehydrogenase (gdh gene; those amplified were subsequently genotyped using NlaIV and RsaI enzymes. The gdh gene was successfully amplified in 74 of 154 ELISA positive samples; 69 of the 74 samples were subsequently genotyped. Of these 69 samples, 42 (61% were classified as assemblage B (26 as BIII and 16 as BIV, 22 (32% as assemblage A (3 as AI and 19 as AII and five (7% as mixed AII and BIII types. In this study site we observe similar diversity in genotypes to other regions in Latin America, though in contrast to some previous studies, we found similar levels of diarrheal symptoms in those individuals infected with assemblage B compared with those infected with assemblage A.

  17. Protection against diarrhea associated with Giardia intestinalis is lost with Multi-Nutrient Supplementation: A Study in Tanzanian Children

    NARCIS (Netherlands)

    Veenemans, J.; Mank, T.; Ottenhof, M.; Baidjoe, A.Y.; Mbugi, E.V.; Demir, A.Y.; Wielders, J.P.M.; Savelkoul, H.F.J.; Verhoef, J.C.M.

    2011-01-01

    Background - Asymptomatic carriage of Giardia intestinalis is highly prevalent among children in developing countries, and evidence regarding its role as a diarrhea-causing agent in these settings is controversial. Impaired linear growth and cognition have been associated with giardiasis, presumably

  18. Investigation into Cryptosporidium and Giardia in bivalve mollusks farmed in Sardinia region and destined for human consumption

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    Tiziana Tedde

    2013-06-01

    Full Text Available Cryptosporidium and Giardia are protozoan parasites transmitted by fecal-oral ingestion of (oocysts, and are responsible for enteritis in several animal species and humans worldwide. These (oocysts can survive for over a year in aquatic environments and can accumulate in bivalve mollusks, which filter large volumes of water. The aim of this study is to evaluate the natural occurrence of Cryptosporidium and Giardia contamination in different specimens of edible bivalves mollusks from farming sites of the western and north-eastern coasts of Sardinia. From April 2011 to February 2012, 1095 specimens of Mytilus galloprovincialis and 240 of Crassostrea gigas were sampled from Olbia and Oristano gulf and San Teodoro pond. Hepatopancreas and gills, including the labial palp, were examined for oocysts and cysts after pooling and homogenisation using different techniques: i staining for light and fluorescence microscopy; ii direct immunofluorescence (IF Merifluor® test Cryptosporidium/ Giardia (Meridian Bioscience Inc., Cincinnati, OH, USA; and iii molecular procedures. However, in the context under study, all mollusks examined with the three main diagnostic techniques were negative for both parasites pointing out the hypothetically low zoonotic risk related to Cryptosporidium and Giardia in bivalves, especially Mytilus galloprovincialis and Crassostrea gigas.

  19. Comparative analysis of enzyme-linked immunosorbent assay and direct microscopy for the diagnosis of Giardia intestinalis in fecal samples

    Directory of Open Access Journals (Sweden)

    Shipra Singhal

    2015-01-01

    Full Text Available Context: Giardiasis is one of the most common nonviral infections causing diarrheal illness worldwide. In this prospective cross-sectional study, we evaluated the RIDASCREEN ® Giardia kit for detection of Giardia intestinalis in stool samples and compared the results with direct microscopy. Materials and methods: A total of 360 fecal samples were collected. They were then processed by wet film, iodine preparation and an enzyme-linked immunosorbent assay (ELISA kit to determine the presence of Giardia trophozoites and cysts. Statistical analysis was performed by sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy. Results and Conclusion: Of the 360 cases, 17.2% samples were positive for Giardia by direct microscopy and 23.6% were found to be positive by ELISA (sensitivity ~97%, but specificity was ~92% only. Because of less specificity, we need to perform ELISA in congruence with direct microscopy, etc. Further studies need to be performed on a larger sample size using other molecular tests in order to get more accurate estimations.

  20. Draft genome sequencing of giardia intestinalis assemblage B isolate GS: is human giardiasis caused by two different species?

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    Oscar Franzén

    2009-08-01

    Full Text Available Giardia intestinalis is a major cause of diarrheal disease worldwide and two major Giardia genotypes, assemblages A and B, infect humans. The genome of assemblage A parasite WB was recently sequenced, and the structurally compact 11.7 Mbp genome contains simplified basic cellular machineries and metabolism. We here performed 454 sequencing to 16x coverage of the assemblage B isolate GS, the only Giardia isolate successfully used to experimentally infect animals and humans. The two genomes show 77% nucleotide and 78% amino-acid identity in protein coding regions. Comparative analysis identified 28 unique GS and 3 unique WB protein coding genes, and the variable surface protein (VSP repertoires of the two isolates are completely different. The promoters of several enzymes involved in the synthesis of the cyst-wall lack binding sites for encystation-specific transcription factors in GS. Several synteny-breaks were detected and verified. The tetraploid GS genome shows higher levels of overall allelic sequence polymorphism (0.5 versus <0.01% in WB. The genomic differences between WB and GS may explain some of the observed biological and clinical differences between the two isolates, and it suggests that assemblage A and B Giardia can be two different species.

  1. Biological and genetic characterization of Cryptosporidium spp. and Giardia duodenalis isolates from five hydrographical basins in northern Portugal.

    Science.gov (United States)

    Almeida, André; Moreira, Maria João; Soares, Sónia; de Lurdes Delgado, Maria; Figueiredo, João; Magalhães, Elisabete Silva; Castro, António; Viana Da Costa, Alexandra; Correia da Costa, José Manuel

    2010-06-01

    To understand the situation of water contamination with Cryptosporidium spp. and Giardia spp. in the northern region of Portugal, we have established a long-term program aimed at pinpointing the sources of surface water and environmental contamination, working with the water-supply industry. Here, we describe the results obtained with raw water samples collected in rivers of the 5 hydrographical basins. A total of 283 samples were analyzed using the Method 1623 EPA, USA. Genetic characterization was performed by PCR and sequencing of genes 18S rRNA of Cryptosporidium spp. and beta-giardin of Giardia spp. Infectious stages of the protozoa were detected in 72.8% (206 of 283) of the water samples, with 15.2% (43 of 283) positive for Giardia duodenalis cysts, 9.5% (27 of 283) positive for Cryptosporidium spp. oocysts, and 48.1% (136 of 283) samples positive for both parasites. The most common zoonotic species found were G. duodenalis assemblages A-I, A-II, B, and E genotypes, and Cryptosporidium parvum, Cryptosporidium andersoni, Cryptosporidium hominis, and Cryptosporidium muris. These results suggest that cryptosporidiosis and giardiasis are important public health issues in northern Portugal. To the authors' knowledge, this is the first report evaluating the concentration of environmental stages of Cryptosporidium and Giardia in raw water samples in the northern region of Portugal.

  2. Intestinal IgA responses to Giardia muris in mice depleted of helper T lymphocytes and in immunocompetent mice.

    Science.gov (United States)

    Heyworth, M F

    1989-04-01

    Immunocompetent mice infected with Giardia muris generate an intestinal antibody response to this parasite and clear G. muris infection. Previous work has shown that G. muris infection is prolonged in mice that have been depleted of helper (CD4+) T lymphocytes by treatment with a monoclonal antibody (mAb) directed against the murine CD4 antigen. The aim of the present study was to compare the intestinal anti-Giardia antibody response in immunocompetent mice and in mice depleted of helper T (Th) lymphocytes by treatment with anti-CD4 mAb. Immunocompetent mice generated an IgA response to G. muris, as judged by the presence of IgA on Giardia trophozoites harvested from the intestine of these animals more than 10 days after the start of the infection. The anti-Giardia IgA response was impaired in mice depleted of Th lymphocytes, as judged by virtual absence of immunofluorescent staining of trophozoites from these animals for surface-bound IgA. Clearance of G. muris infection was impaired by treatment of mice with anti-CD4 mAb. The results suggest that Th (CD4+) lymphocytes are important for the generation of a local IgA response against G. muris trophozoites in the mouse intestine and that IgA anti-trophozoite antibody may contribute to the clearance of G. muris from the intestine of immunocompetent mice.

  3. Relationships between the occurrence of Giardia and Cryptosporidium and physicochemical properties of marine waters of the Pacific Coast of Mexico.

    Science.gov (United States)

    Magana-Ordorica, Dalia; Mena, Kristina; Valdez-Torres, Jose B; Soto-Beltran, Marcela; Leon-Felix, Josefina; Chaidez, Cristobal

    2010-12-01

    Untreated sewage has adversely affected the quality of marine recreational waters worldwide. Exposure to marine recreational water with poor microbial quality may pose a threat to bathers. The objectives of this study were to assess the effect of physicochemical parameters on Cryptosporidium and Giardia presence in marine recreational water of Sinaloa, Mexico, by Logistic Regression Analyses. Thirty-two 10-litre water samples were collected from two tourist beaches, Altata and Mazatlan, between November 2006 and May 2007. Water samples were processed by the EPA 1623 method and pH, temperature, salinity and turbidity were also determined. Cryptosporidium and Giardia were present in 71 and 57% of the samples collected from Altata, respectively. In Mazatlan, Cryptosporidium and Giardia were found in 83 and 72% of the samples, respectively. The overall concentration of Cryptosporidium ranged from 150 to 2,050 oocysts/10 L with an average of 581 oocysts/10 L and Giardia ranged from 10 to 300 cysts/10 L with an average of 73 cysts/10 L. The occurrence of both parasites increased in water with decreasing temperatures and increasing turbidity of the water.

  4. Comparison of ELISA, nested PCR and sequencing and a novel qPCR for detection of Giardia isolates from Jordan.

    Science.gov (United States)

    Hijjawi, Nawal; Yang, Rongchang; Hatmal, Ma'mon; Yassin, Yasmeen; Mharib, Taghrid; Mukbel, Rami; Mahmoud, Sameer Alhaj; Al-Shudifat, Abdel-Ellah; Ryan, Una

    2018-02-01

    Little is known about the prevalence of Giardia duodenalis in human patients in Jordan and all previous studies have used direct microscopy, which lacks sensitivity. The present study developed a novel quantitative PCR (qPCR) assay at the β-giardin (bg) locus and evaluated its use as a frontline test for the diagnosis of giardiasis in comparison with a commercially available ELISA using nested PCR and sequencing of the glutamate dehydrogenase (gdh) locus (gdh nPCR) as the gold standard. A total of 96 human faecal samples were collected from 96 patients suffering from diarrhoea from 5 regions of Jordan and were screened using the ELISA and qPCR. The analytical specificity of the bg qPCR assay revealed no cross-reactions with other genera and detected all the Giardia isolates tested. Analytical sensitivity was 1 Giardia cyst per μl of DNA extract. The overall prevalence of Giardia was 64.6%. The clinical sensitivity and specificity of the bg qPCR was 89.9% and 82.9% respectively compared to 76.5 and 68.0% for the ELISA. This study is the first to compare three different methods (ELISA, bg qPCR, nested PCR and sequencing at the gdh locus) to diagnose Jordanian patients suffering from giardiasis and to analyze their demographic data. Copyright © 2018 Elsevier Inc. All rights reserved.

  5. Molecular epidemiology and multilocus sequence analysis of potentially zoonotic Giardia spp. from humans and dogs in Jamaica.

    Science.gov (United States)

    Lee, Mellesia F; Cadogan, Paul; Eytle, Sarah; Copeland, Sonia; Walochnik, Julia; Lindo, John F

    2017-01-01

    Giardia spp. are the causative agents of intestinal infections in a wide variety of mammals including humans and companion animals. Dogs may be reservoirs of zoonotic Giardia spp.; however, the potential for transmission between dogs and humans in Jamaica has not been studied. Conventional PCR was used to screen 285 human and 225 dog stool samples for Giardia targeting the SSU rDNA gene followed by multilocus sequencing of the triosephosphate isomerase (tpi), glutamate dehydrogenase (gdh), and β-giardin (bg) genes. Prevalence of human infections based on PCR was 6.7 % (19/285) and canine infections 19.6 % (44/225). Nested PCR conducted on all 63 positive samples revealed the exclusive presence of assemblage A in both humans and dogs. Sub-assemblage A-II was responsible for 79.0 % (15/19) and 70.5 % (31/44) of the infections in humans and dogs, respectively, while sub-assemblage A-I was identified at a rate of 15.8 % (3/19) and 29.5 % (13/44) in humans and dogs, respectively. The predominance of a single circulating assemblage among both humans and dogs in Jamaica suggests possible zoonotic transmission of Giardia infections.

  6. Prevalence of Giardia duodenalis and Cryptosporidium species infections among children and cattle in North Shewa Zone, Ethiopia.

    Science.gov (United States)

    Wegayehu, Teklu; Adamu, Haileeyesus; Petros, Beyene

    2013-09-08

    Giardia and Cryptosporidium are the most common causes of protozoan diarrhea that lead to significant morbidity and mortality worldwide. The purpose of this study was to determine the prevalence of Giardia duodenalis and Cryptosporidium species infections among children and cattle, and to assess the potential risk of zoonotic transmission. This cross-sectional study was conducted between January and April 2009 in Girar Jarso and Dera Districts of North Shewa Zone, Oromia Region, Ethiopia. A total of 768 stool specimens were collected and examined for intestinal parasites using direct wet mount with saline and formalin ether concentration methods. The modified Ziehl-Neelsen staining method was used for the detection of Cryptosporidium species. Statistical analysis was performed using SPSS software version 15. Out of 384 children examined, 53 (13.8%) and 28 (7.3%) were positive for Giardia and Cryptosporidium infections, respectively. Similarly, of the total 384 cattle examined, 9 (2.3%) were positive for Giardia duodenalis and 30 (7.8%) were positive for Cryptosporidium infection. The prevalence of giardiasis was significantly higher among children who had close contact with cattle 33 (18.7%) compared to children who had no contact with cattle 20 (9.6%) (P < 0.05). Higher number of Cryptosporidium infection was also recorded in children who had close contact with cattle 15 (8.5%). Difference in prevalence of giardiasis and cryptosporidiosis among children was not statistically significant between males and females. On the other hand, difference in the prevalence of giardiasis among children was statistically significant between age groups. Higher prevalence of Giardia duodenalis infection detected among children was significantly associated with contact with cattle and manure that the children had. Further analysis using molecular techniques is needed to explain the existence of zoonotic transmission in the study area.

  7. Risk assessment of Giardia from a full scale MBR sewage treatment plant caused by membrane integrity failure.

    Science.gov (United States)

    Zhang, Yu; Chen, Zhimin; An, Wei; Xiao, Shumin; Yuan, Hongying; Zhang, Dongqing; Yang, Min

    2015-04-01

    Membrane bioreactors (MBR) are highly efficient at intercepting particles and microbes and have become an important technology for wastewater reclamation. However, many pathogens can accumulate in activated sludge due to the long residence time usually adopted in MBR, and thus may pose health risks when membrane integrity problems occur. This study presents data from a survey on the occurrence of water-borne Giardia pathogens in reclaimed water from a full-scale wastewater treatment plant with MBR experiencing membrane integrity failure, and assessed the associated risk for green space irrigation. Due to membrane integrity failure, the MBR effluent turbidity varied between 0.23 and 1.90 NTU over a period of eight months. Though this turbidity level still met reclaimed water quality standards (≤5 NTU), Giardia were detected at concentrations of 0.3 to 95 cysts/10 L, with a close correlation between effluent turbidity and Giardia concentration. All β-giardin gene sequences of Giardia in the WWTP influents were genotyped as Assemblages A and B, both of which are known to infect humans. An exponential dose-response model was applied to assess the risk of infection by Giardia. The risk in the MBR effluent with chlorination was 9.83×10(-3), higher than the acceptable annual risk of 1.0×10(-4). This study suggested that membrane integrity is very important for keeping a low pathogen level, and multiple barriers are needed to ensure the biological safety of MBR effluent. Copyright © 2015. Published by Elsevier B.V.

  8. A Modified EPA Method 1623 that Uses Tangential Flow Hollow-Fiber Ultrafiltration and Heat Dissociation Steps to Detect Waterborne Cryptosporidum and Giardia spp.

    Science.gov (United States)

    This protocol describes the use of a tangential flow hollow-fiber ultrafiltration sample concentration system and a heat dissociation as alternative steps for the detection of waterborne Cryptosporidium and Giardia species using EPA Method 1623.

  9. Multilocus typing of Cryptosporidium spp. and Giardia duodenalis from non-human primates in China.

    Science.gov (United States)

    Karim, Md Robiul; Zhang, Sumei; Jian, Fuchun; Li, Jiacheng; Zhou, Chunxiang; Zhang, Longxian; Sun, Mingfei; Yang, Guangyou; Zou, Fengcai; Dong, Haiju; Li, Jian; Rume, Farzana Islam; Qi, Meng; Wang, Rongjun; Ning, Changshen; Xiao, Lihua

    2014-11-01

    Non-human primates (NHPs) are commonly infected with Cryptosporidium spp. and Giardia duodenalis. However, molecular characterisation of these pathogens from NHPs remains scarce. In this study, 2,660 specimens from 26 NHP species in China were examined and characterised by PCR amplification of 18S rRNA, 70kDa heat shock protein (hsp70) and 60kDa glycoprotein (gp60) gene loci for Cryptosporidium; and 1,386 of the specimens by ssrRNA, triosephosphate isomerase (tpi) and glutamate dehydrogenase (gdh) gene loci for Giardia. Cryptosporidium was detected in 0.7% (19/2660) specimens of four NHP species including rhesus macaques (0.7%), cynomolgus monkeys (1.0%), slow lorises (10.0%) and Francois' leaf monkeys (6.7%), belonging to Cryptosporidium hominis (14/19) and Cryptosporidium muris (5/19). Two C. hominis gp60 subtypes, IbA12G3 and IiA17 were observed. Based on the tpi locus, G. duodenalis was identified in 2.2% (30/1,386) of specimens including 2.1% in rhesus macaques, 33.3% in Japanese macaques, 16.7% in Assam macaques, 0.7% in white-headed langurs, 1.6% in cynomolgus monkeys and 16.7% in olive baboons. Sequence analysis of the three targets indicated that all of the Giardia-positive specimens belonged to the zoonotic assemblage B. Highest sequence polymorphism was observed at the tpi locus, including 11 subtypes: three known and eight new ones. Phylogenetic analysis of the subtypes showed that most of them were close to the so-called subtype BIV. Intragenotypic variations at the gdh locus revealed six types of sequences (three known and three new), all of which belonged to so-called subtype BIV. Three specimens had co-infection with C. hominis (IbA12G3) and G. duodenalis (BIV). The presence of zoonotic genotypes and subtypes of Cryptosporidium spp. and G. duodenalis in NHPs suggests that these animals can potentially contribute to the transmission of human cryptosporidiosis and giardiasis. Copyright © 2014 Australian Society for Parasitology Inc. All rights

  10. The crystal structure of Giardia duodenalis 14-3-3 in the apo form: when protein post-translational modifications make the difference.

    KAUST Repository

    Fiorillo, Annarita

    2014-03-21

    The 14-3-3s are a family of dimeric evolutionary conserved pSer/pThr binding proteins that play a key role in multiple biological processes by interacting with a plethora of client proteins. Giardia duodenalis is a flagellated protozoan that affects millions of people worldwide causing an acute and chronic diarrheal disease. The single giardial 14-3-3 isoform (g14-3-3), unique in the 14-3-3 family, needs the constitutive phosphorylation of Thr214 and the polyglycylation of its C-terminus to be fully functional in vivo. Alteration of the phosphorylation and polyglycylation status affects the parasite differentiation into the cyst stage. To further investigate the role of these post-translational modifications, the crystal structure of the g14-3-3 was solved in the unmodified apo form. Oligomers of g14-3-3 were observed due to domain swapping events at the protein C-terminus. The formation of filaments was supported by TEM. Mutational analysis, in combination with native PAGE and chemical cross-linking, proved that polyglycylation prevents oligomerization. In silico phosphorylation and molecular dynamics simulations supported a structural role for the phosphorylation of Thr214 in promoting target binding. Our findings highlight unique structural features of g14-3-3 opening novel perspectives on the evolutionary history of this protein family and envisaging the possibility to develop anti-giardial drugs targeting g14-3-3.

  11. The crystal structure of Giardia duodenalis 14-3-3 in the apo form: when protein post-translational modifications make the difference.

    Directory of Open Access Journals (Sweden)

    Annarita Fiorillo

    Full Text Available The 14-3-3s are a family of dimeric evolutionary conserved pSer/pThr binding proteins that play a key role in multiple biological processes by interacting with a plethora of client proteins. Giardia duodenalis is a flagellated protozoan that affects millions of people worldwide causing an acute and chronic diarrheal disease. The single giardial 14-3-3 isoform (g14-3-3, unique in the 14-3-3 family, needs the constitutive phosphorylation of Thr214 and the polyglycylation of its C-terminus to be fully functional in vivo. Alteration of the phosphorylation and polyglycylation status affects the parasite differentiation into the cyst stage. To further investigate the role of these post-translational modifications, the crystal structure of the g14-3-3 was solved in the unmodified apo form. Oligomers of g14-3-3 were observed due to domain swapping events at the protein C-terminus. The formation of filaments was supported by TEM. Mutational analysis, in combination with native PAGE and chemical cross-linking, proved that polyglycylation prevents oligomerization. In silico phosphorylation and molecular dynamics simulations supported a structural role for the phosphorylation of Thr214 in promoting target binding. Our findings highlight unique structural features of g14-3-3 opening novel perspectives on the evolutionary history of this protein family and envisaging the possibility to develop anti-giardial drugs targeting g14-3-3.

  12. The crystal structure of Giardia duodenalis 14-3-3 in the apo form: when protein post-translational modifications make the difference.

    KAUST Repository

    Fiorillo, Annarita; di Marino, Daniele; Bertuccini, Lucia; Via, Allegra; Pozio, Edoardo; Camerini, Serena; Ilari, Andrea; Lalle, Marco

    2014-01-01

    The 14-3-3s are a family of dimeric evolutionary conserved pSer/pThr binding proteins that play a key role in multiple biological processes by interacting with a plethora of client proteins. Giardia duodenalis is a flagellated protozoan that affects millions of people worldwide causing an acute and chronic diarrheal disease. The single giardial 14-3-3 isoform (g14-3-3), unique in the 14-3-3 family, needs the constitutive phosphorylation of Thr214 and the polyglycylation of its C-terminus to be fully functional in vivo. Alteration of the phosphorylation and polyglycylation status affects the parasite differentiation into the cyst stage. To further investigate the role of these post-translational modifications, the crystal structure of the g14-3-3 was solved in the unmodified apo form. Oligomers of g14-3-3 were observed due to domain swapping events at the protein C-terminus. The formation of filaments was supported by TEM. Mutational analysis, in combination with native PAGE and chemical cross-linking, proved that polyglycylation prevents oligomerization. In silico phosphorylation and molecular dynamics simulations supported a structural role for the phosphorylation of Thr214 in promoting target binding. Our findings highlight unique structural features of g14-3-3 opening novel perspectives on the evolutionary history of this protein family and envisaging the possibility to develop anti-giardial drugs targeting g14-3-3.

  13. Occurrence of Giardia and Cryptosporidium in captive chimpanzees (Pan troglodytes), mandrills (Mandrillus sphinx) and wild Zanzibar red colobus monkeys (Procolobus kirkii).

    Science.gov (United States)

    Debenham, John J; Atencia, Rebeca; Midtgaard, Fred; Robertson, Lucy J

    2015-04-01

    The aim of this study was to investigate the occurrence of Giardia duodenalis and Cryptosporidium spp. in primates and determine their zoonotic or anthropozoonotic potential. Direct immunofluorescence was used to identify Giardia and Cryptosporidium from faecal samples. PCR and DNA sequencing was performed on positive results. Giardia cysts were identified from 5.5% (5/90) of captive chimpanzees and 0% (0/11) of captive mandrills in the Republic of Congo; 0% (0/10) of captive chimpanzees in Norway; and 0% of faecal samples (n = 49) from wild Zanzibar red colobus monkeys. Two Giardia positive samples were also positive on PCR, and sequencing revealed identical isolates of Assemblage B. Cryptosporidium oocysts were not detected in any of the samples. In these primate groups, in which interactions with humans and human environments are quite substantial, Giardia and Cryptosporidium are rare pathogens. In chimpanzees, Giardia may have a zoonotic or anthropozoonotic potential. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Giardia SP y su participación en las alteraciones nutricionales

    OpenAIRE

    Abril Garrido, Paola

    2016-01-01

    La Giardia es un protozoo flagelado y binucleado que infecta al hombre y a otros mamíferos. La transmisión se produce por la ingesta de quistes presentes en agua o alimentos. En el huésped el parásito reside normalmente en la parte proximal del intestino delgado donde absorbe alimentos. La infección puede producir irritación progresiva de la mucosa intestinal que desemboca en una enteropatía con malabsorción y diarrea crónica. Los síntomas más característicos son dolor epigástrico, flatulenci...

  15. Molecular and phylogenetic characterization of Cryptosporidium and Giardia from pigs and cattle in Denmark

    DEFF Research Database (Denmark)

    Langkjær, Rikke Breinhold; Vigre, Håkan; Enemark, Heidi L.

    2007-01-01

    The genetic diversity of Cryptosporidium spp. and Giardia duodenalis from dairy cattle and pigs in Denmark was determined in the present study. Faecal samples from 1237 pigs and 1150 cattle originating from 50 sow herds and 50 dairy herds, respectively, were analysed for the presence of the two...... parasites by immunofluorescence microscopy. A large proportion of the (oo)cyst containing samples were selected for molecular characterization. Sequencing and phylogenetic analysis of the 18S rDNA locus and/or the HSP70 gene of 183 pig and 154 cattle isolates of Cryptosporidium revealed the presence of C....... suis, pig genotype II, C. parvum (cattle genotype), C. bovis, Cryptosporidium deer-like genotype and a novel C. suis-like genotype. For both cattle and pigs, a host age-related change in distribution of species/genotypes was observed. The zoonotic C. parvum (cattle genotype) was most prevalent in young...

  16. New filtration system for efficient recovery of waterborne Cryptosporidium oocysts and Giardia cysts

    DEFF Research Database (Denmark)

    Al-Sabi, Mohammad Nafi Solaiman; Gad, J. A.; Riber, Ulla

    2015-01-01

    -)cysts (1x10(2); 10 replicates) was successfully amplified using real-time PCR.ConclusionsThe use of a metallic filter, sonication and air backwash' were key factors for creating a highly efficient system for recovery of apparently undamaged protozoa.Significance and Impact of the StudyThis reagent......AimsTo develop a filtration unit for efficient recovery of waterborne Cryptosporidium oocysts and Giardia cysts ((oo-)cysts) in drinking water.Methods and ResultsThis unit utilizes a metallic filter and an ultrasound transducer for eluting (oo-)cysts, with a fixed retentate backwash volume; approx....... 400l. Changes in the viability was evaluated by seeding wild type (oo-)cysts (1x10(4)) followed by sonication for 5, 10, 20 or 40s (five replicates for each period). Flow cytometry analysis showed negligible increase in the mortality of (oo-)cysts exposed to 5-10s of sonication. Recovery rate...

  17. Effects of Ultrasound on the Survival and Characteristics of Cryptosporidium Oocysts and Giardia Cysts

    DEFF Research Database (Denmark)

    Al-Sabi, Mohammad Nafi Solaiman; Gad, J.; Klinting, M.

    2011-01-01

    determine the effects of ultrasound on the parasite, including the sonication power of ultrasound as well as substrate temperature. Conclusions: Ultrasound is harmful for waterborne protozoa even when momentarily applied. However, a mode of operation may exist in which ultrasound can be used for collection......-. Additionally ultrasound has been used for cleaning filters used for water sampling and purification. Other studies have shown that backwash sampling of filtrates, and thereby collection of microorganisms, can be facilitated by sonication. Methods: We studied the effects of ultrasound with different sonication...... power and time durations on two of the most common waterborne protozoa Cryptosporidium and Giardia, and examined its effects on parasite characteristics and survival rate using immunofluorescence dyes; DAPI (4’,6-diamidino-2-phenylindol) staining/PI (propidium iodide), and analyzed by flow cytometry...

  18. Comparison of the course of infection with Giardia muris in male and female mice.

    Science.gov (United States)

    Daniels, C W; Belosevic, M

    1995-01-01

    The infection with Giardia muris in male and female C57BL/6 mice was characterized by enumerating cyst release in the feces and trophozoite burden in the small intestine. Cyst release differed between males and females during the course of the primary and challenge infections. Males and females released similar numbers of cysts in the feces during the acute phase of the infection. However, the trophozoite burden was significantly higher in males during the same period. Males released cysts in their feces longer than females and trophozoites present in their intestines for a longer period than females. From day 18 of infection the females did not release cysts in their feces, while males continued to do so for at least 60 days. Thus, distinct differences exist between male and female mice in their ability to harbor and eliminate this intestinal parasite.

  19. Minimal infectious doses and prepatent periods in Giardia muris, Spironucleus muris and Tritrichomonas muris.

    Science.gov (United States)

    Stachan, R; Kunstýr, I

    1983-12-01

    The minimal infectious doses (MID) of Giardia muris cysts, Spironucleus muris cysts and Tritrichomonas muris pseudocysts for athymic mice were determined. A novel micromanipulator-aided technique was developed for selecting small exact numbers of specified fresh or old cysts/pseudocysts from a faecal homogenate. This technique can also be of value in manipulating protozoan parasites of any particular species. Only fresh cysts/pseudocysts, which appeared bright under phase contrast optics, were infectious. Older cysts and pseudocysts which appeared dark in phase contrast were not infectious. The MID for three murine intestinal flagellates addressed above were: 10 (between 5 and 20), 1 and 5 cysts/pseudocysts respectively. Corresponding prepatent periods (PP) were 8, 5 and 10 days. A relation was evident between the infectious dose and the PP: The prepatent period shortened with an increased infectious dose.

  20. Activities of several benzimidazoles and tubulin inhibitors against Giardia spp. in vitro.

    Science.gov (United States)

    Morgan, U M; Reynoldson, J A; Thompson, R C

    1993-01-01

    Previous studies in our laboratory have shown that albendazole is effective against Giardia spp. in vitro and in vivo, prompting an investigation of the effects of several related benzimidazoles (BZs) on the viability of this protozoan parasite. A range of BZs was tested, and their effects were compared with those of a number of microtubule inhibitors. The effects produced by the two types of drugs were markedly similar, namely, trophozoite detachment and distortion of morphology and general structure, indicating a potential antimicrotubule mode of action for BZs. Mebendazole, albendazole, and fenbendazole proved to be among the most effective BZs tested, exhibiting apparent irreversibility. Nocodazole, oxfendazole, and albendazole sulfoxide, among others, produced transient inhibitions only. Further studies are required to evaluate all available BZs and other antigiardial agents to ensure the development of the most effective and safest antigiardial agent possible. PMID:8452365

  1. Giardia duodenalis infection: risk factors for children living in sub-standard settlements in Brazil

    Directory of Open Access Journals (Sweden)

    Júlio César Teixeira

    2007-06-01

    Full Text Available The objective of the present study was to characterize Giardia duodenalis infection among children living in sub-standard settlement areas in the municipality of Juiz de Fora, Minas Gerais State, Brazil. The cross-sectional epidemiological study included 590 children from 1 to 5 years of age. Data were collected from one child per selected family through home interviews with the parent or guardian and parasitological examination of stool samples. Thirty-one putative risk factors concerning family structure, socioeconomic status, and environmental factors were analyzed by multivariate logistic regression. Prevalence of G. duodenalis infection was 18% (106 children. Four potential risk factors were heavily associated with G. duodenalis infection: number of under-five children in the same household, index child's birth order, existence of a bathroom in the home, and drinking water source.

  2. Prevalence and molecular characterization of Cryptosporidium spp. and Giardia duodenalis in diarrhoeic patients in the Qikiqtani Region, Nunavut, Canada

    Directory of Open Access Journals (Sweden)

    Asma Iqbal

    2015-06-01

    Full Text Available Background: Although the prevalences of infection with the protozoan parasites Cryptosporidium spp. and Giardia duodenalis in humans appear to be relatively high in the Canadian North, their transmission patterns are poorly understood. Objective: To determine the detection rate and the molecular characteristics of Cryptosporidium spp. and Giardia duodenalis in diarrhoeic patients in the Qikiqtani (Baffin Island Region of Nunavut, Canada, in order to better understand the burden of illness and the potential mechanisms of transmission. Study design/methods: Diarrhoeal stool specimens (n=108 submitted to the Qikiqtani General Hospital for clinical testing were also tested for the presence of Cryptosporidium spp. and Giardia duodenalis using epifluorescence microscopy and polymerase chain reaction (PCR. DNA sequencing and restriction fragment length polymorphism (RFLP analyses were performed on PCR-positive specimens to determine the species, genotypes and sub-genotypes of the parasites. Results: Cryptosporidium was detected in 15.7% of the diarrhoeic patients, while Giardia was detected in 4.6%. DNA sequencing of a fragment of the small subunit rRNA gene indicated that all of the Cryptosporidium amplicons had a 100% homology to C. parvum, and a gp60 assay showed that all aligned with C. parvum sub-genotype IIa. Microsatellite analysis revealed 3 cases of sub-genotype IIaA15G2R1, 2 of IIaA15G1R and 1 case each of sub-genotypes IIaA16G1R1 and IIaA15R1. For Giardia, results based on the amplification of both the 16S rRNA gene and the gdh gene were generally in agreement, and both DNA sequencing and RFLP demonstrated the presence of the G. duodenalis Assemblage B genotype. Conclusions: Both C. parvum and G. duodenalis Assemblage B were present in human diarrhoeal stool specimens from Nunavut, which was suggestive of zoonotic transmission, although human-to-human transmission cannot be ruled out. To fully understand the public health significance of the

  3. Prevalence of Cryptosporidium spp. and Giardia duodenalis in pigs in Lusaka, Zambia

    Directory of Open Access Journals (Sweden)

    Joyce Siwila

    2012-02-01

    Full Text Available This study was aimed at determining the prevalence of Cryptosporidium spp. and Giardia duodenalis in pigs which were being raised in intensive management systems. Faecal samples were collected from pigs of all age groups from three different piggery units. Samples were collected directly from the rectum for piglets and weaners and from the floor within 2 min – 5 min of excretion for sows and boars. At the time of collection, faecal consistency was noted as being normal, pasty or diarrhoeic. Samples were analysed further using the Merifluor® Cryptosporidium/Giardia immunofluorescence assay. All piggeries had at least one pig infected with either parasite. From a total 217 samples collected, 96 (44.2%; confidence interval [CI] = 37.6% – 50.9% were positive for Cryptosporidium spp., whilst 26 (12%; CI = 7.6% – 16.3% had G. duodenalis parasites. Of all the pigs, 6.9% (15/217 harboured both parasites. With regard to Cryptosporidium spp. infection, statistically significant differences were observed amongst the three units (p = 0.001, whereas no significant differences were observed for G. duodenalis infection (p = 0.13. Prevalence was higher in weaners as compared to other pig classes for both parasites, with significant differences being observed for G. duodenalis infection (p = 0.013. There was, however, no difference in infection between male and female pigs for both parasites. Furthermore, most infections were asymptomatic. From the study results it was clear that Cryptosporidium spp. and G. duodenalis infections were prevalent amongst pigs in the piggeries evaluated and, as such, may act as a source of infection for persons who come into contact with them.

  4. Bile Salt Hydrolase Activities: A Novel Target to Screen Anti-Giardia Lactobacilli?

    Directory of Open Access Journals (Sweden)

    Thibault Allain

    2018-02-01

    Full Text Available Giardia duodenalis is a protozoan parasite responsible for giardiasis, a disease characterized by intestinal malabsorption, diarrhea and abdominal pain in a large number of mammal species. Giardiasis is one of the most common intestinal parasitic diseases in the world and thus a high veterinary, and public health concern. It is well-established that some probiotic bacteria may confer protection against this parasite in vitro and in vivo and we recently documented the implication of bile-salt hydrolase (BSH-like activities from strain La1 of Lactobacillus johnsonii as mediators of these effects in vitro. We showed that these activities were able to generate deconjugated bile salts that were toxic to the parasite. In the present study, a wide collection of lactobacilli strains from different ecological origins was screened to assay their anti-giardial effects. Our results revealed that the anti-parasitic effects of some of the strains tested were well-correlated with the expression of BSH-like activities. The two most active strains in vitro, La1 and Lactobacillus gasseri CNCM I-4884, were then tested for their capacity to influence G. duodenalis infection in a suckling mice model. Strikingly, only L. gasseri CNCM I-4884 strain was able to significantly antagonize parasite growth with a dramatic reduction of the trophozoites load in the small intestine. Moreover, this strain also significantly reduced the fecal excretion of Giardia cysts after 5 days of treatment, which could contribute to blocking the transmission of the parasite, in contrast of La1 where no effect was observed. This study represents a step toward the development of new prophylactic strategies to combat G. duodenalis infection in both humans and animals.

  5. Occurrence of Giardia cysts and Cryptosporidium oocysts in activated sludge samples in Campinas, SP, Brazil Ocorrência de cistos de Giardia e oocistos de Cryptosporidium em amostras de lodo ativado em Campinas, SP, Brasil

    Directory of Open Access Journals (Sweden)

    Luciana Urbano Santos

    2004-04-01

    Full Text Available Giardia and Cryptosporidium have caused several outbreaks of gastroenteritis in humans associated with drinking water. Contaminated sewage effluents are recognized as a potential source of waterborne protozoa. Due to the lack of studies about the occurrence of these parasites in sewage samples in Brazil, we compared the efficiency of two procedures for concentrating cysts and oocysts in activated sludge samples of one sewage treatment plant. For this, the samples were submitted to i concentration by the ether clarification procedure (ECP and to ii purification by sucrose flotation method (SFM and aliquots of the pellets were examined by immunofluorescence. Giardia cysts were present in all samples (100.0%; n = 8 when using ECP and kit 1 reagents, while kit 2 resulted in six positive samples (85.7%; n = 7. As for SFM, cysts were detected in 75.0% and 100.0% of these samples (for kit 1 and 2, respectively. Regarding Cryptosporidium, two samples (25.0%; kit 1 and 28.5% for kit 2 were detected positive by using ECP, while for SFM, only one sample (examined by kit 1 was positive (12.5%. The results of the control trial revealed Giardia and Cryptosporidium recovery efficiency rates for ECP of 54.5% and 9.6%, while SFM was 10.5% and 3.2%, respectively. Considering the high concentration detected, a previous evaluation of the activated sludge before its application in agriculture is recommended and with some improvement, ECP would be an appropriate simple technique for protozoa detection in sewage samples.Giardia e Cryptosporidium causaram vários surtos epidêmicos de gastroenterite, associados à água potável. Efluentes de esgoto contaminados foram incriminados como uma fonte potencial de cistos e oocistos. Uma investigação foi conduzida para verificar a presença de cistos de Giardia e oocistos de Cryptosporidium em amostras de lodo ativado de uma Estação de Tratamento de Esgoto. Para isto as amostras foram submetidas: i a concentração pelo

  6. Giardia infection

    Science.gov (United States)

    ... eds. Goldman-Cecil Medicine . 25th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 283. Haines CF, Sears CL. ... Gastrointestinal and Liver Disease . 10th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 110. Nash TE, Hill DR. ...

  7. Age-dependent decline and association with stunting of Giardia duodenalis infection among schoolchildren in rural Huye district, Rwanda.

    Science.gov (United States)

    Heimer, Jakob; Staudacher, Olga; Steiner, Florian; Kayonga, Yvette; Havugimana, Jean Marie; Musemakweri, Andre; Harms, Gundel; Gahutu, Jean-Bosco; Mockenhaupt, Frank P

    2015-05-01

    Giardia duodenalis infection is highly prevalent and a cause of underweight in pre-school children in rural Rwanda. The present study aimed at assessing the age-pattern of Giardia infection and its manifestation in older children, i.e., during school age. Stool samples were collected from 622 schoolchildren at two schools in the Huye district of southern Rwanda (rural, 301; urban, 321) and subjected to G. duodenalis specific PCR assays. Clinical and anthropometric data, socio-economic status and factors potentially associated with G. duodenalis infection were assessed. Of the 622 children (mean age, 10.4 years), 35.7% were infected with G. duodenalis (rural, 43.9%; urban, 28.0%; PRwanda, G. duodenalis prevalence among children declined throughout school-age. The data suggest that while lacking overt clinical manifestation at high endemicity, G. duodenalis infection is a common cause of stunting in schoolchildren. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Prevalence of Giardia duodenalis assemblages in weaned cattle on cow-calf operations in the United States.

    Science.gov (United States)

    Santin, Monica; Dargatz, David; Fayer, Ronald

    2012-02-10

    To determine the prevalence of Giardia duodenalis in weaned beef calves on cow-calf operations in the United States, fecal specimens were collected from 819 calves (6-18 months of age) from 49 operations. After cleaning and concentration procedures to maximize recovery of cysts from feces, DNA was extracted from each of the 819 specimens. The presence of G. duodenalis was determined by nested PCR of a fragment of the SSU rRNA gene. All positive PCR products were subjected to sequence analysis. The overall sample level prevalence of Giardia was 33.5% with prevalence ranging from 0 to 100% among operations. The highest within herd prevalence of infected beef calves was found in one cow-calf operation from the South region (100%), followed by a cow-calf operation from the West region (90%), and three cow-calf operations from the Midwest region (87.5, 85, and 85%). Giardia was not detected in samples from 7 operations including 5 cow-calf operations from the South region, and 1 cow-calf operation each from the Midwest and West regions. Molecular analysis of the Giardia-positive samples identified assemblage E (or E-like) in 31.7% of all samples (260/819) and assemblage A in 1.2% (10/819). A mixed infection with assemblages A and E was observed in four calves from an operation in Midwest region. The potentially zoonotic assemblage A was detected in specimens from four operations in Midwest region. These findings indicate that most G. duodenalis found in weaned beef calves was assemblage E which represents no known zoonotic threat. However, the presence of assemblage A in a small number of animals poses a potential risk of infection to humans. Published by Elsevier B.V.

  9. Prokaryotic and eukaryotic features observed on the secondary structures of Giardia SSU rRNAs and its phylogenetic implications.

    Science.gov (United States)

    Hwang, Ui Wook

    2007-04-01

    Phylogenetic position of a diplomonad protist Giardia, a principle cause of diarrhea, among eukaryotes has been vigorously debated so far. Through the comparisons of primary and secondary structures of SSU rRNAs of G. intestinalis, G. microti, G. ardeae, and G. muris, I found two major indel regions (a 6-nt indel and a 22-26-nt indel), which correspond to the helix 10 of the V2 region and helices E23-8 to E23-9 of the V4 region, respectively. As generally shown in eukaryotes, G. intestinalis and G. microti have commonly a relatively longer helix 10 (a 7-bp stem and a 4-nt loop), and also the eukaryote-specific helices E23-6 to E23-9. On the other hand, G. muris and G. ardeae have a shorter helix 10: a 2-bp stem and a 6-nt loop in G. ardeae and a 3-bp stem and a 6-nt loop in G. muris. In the V4, they have a single long helix (like the P23-1 helix in prokaryotes) instead of the helices E23-6 to E23-9. Among the four Giardia species, co-appearance of prokaryote- and eukaryote-typical features might be significant evidence to suggest that Giardia (Archezoa) is a living fossil showing an "intermediate stage" during the evolution from prokaryotes to eukaryotes.

  10. Quantitative microbial risk assessment of Cryptosporidium and Giardia in well water from a native community of Mexico.

    Science.gov (United States)

    Balderrama-Carmona, Ana Paola; Gortáres-Moroyoqui, Pablo; Álvarez-Valencia, Luis Humberto; Castro-Espinoza, Luciano; Balderas-Cortés, José de Jesús; Mondaca-Fernández, Iram; Chaidez-Quiroz, Cristóbal; Meza-Montenegro, María Mercedes

    2015-01-01

    Cryptosporidium and Giardia are gastrointestinal disease-causing organisms transmitted by the fecal-oral route, zoonotic and prevalent in all socioeconomic segments with greater emphasis in rural communities. The goal of this study was to assess the risk of cryptosporidiosis and giardiasis of Potam dwellers consuming drinking water from communal well water. To achieve the goal, quantitative microbial risk assessment (QMRA) was carried out as follows: (a) identification of Cryptosporidium oocysts and Giardia cysts in well water samples by information collection rule method, (b) assessment of exposure to healthy Potam residents, (c) dose-response modelling, and (d) risk characterization using an exponential model. All well water samples tested were positive for Cryptosporidium and Giardia. The QMRA results indicate a mean of annual risks of 99:100 (0.99) for cryptosporidiosis and 1:1 (1.0) for giardiasis. The outcome of the present study may drive decision-makers to establish an educational and treatment program to reduce the incidence of parasite-borne intestinal infection in the Potam community, and to conduct risk analysis programs in other similar rural communities in Mexico.

  11. Field testing of a fenbendazole treatment combined with hygienic and management measures against a natural Giardia infection in calves.

    Science.gov (United States)

    Geurden, Thomas; Vercruysse, Jozef; Claerebout, Edwin

    2006-12-20

    The need of a combination of animal treatment and environmental measures against a natural Giardia infection in calves between the age of 1 and 6 months was emphasized and evaluated. Ten commercial farms with a total of 94 calves suffering from chronic diarrhea, ill thriving and impaired growth, were included in two subsequent studies. The first study indicated that treatment of all animals with fenbendazole at 15 mg/kg during 3 consecutive days combined with environmental measures on the final day of treatment, which were either removal of bedding, thorough cleaning and ammonia 10% disinfection or relocation of the treated animals to a Giardia free environment, resulted in a total reduction in cyst excretion for at least 2 weeks. In the second study, the immunofluorescence assay (Merifluor Cryptosporidium/Giardia; Meridian Diagnostics Inc., Cincinnati, Ohio) was used quantitatively and confirmed that the combination of treatment and environmental measures resulted in a total reduction of cyst excretion during 2 weeks and in a significant (Por=98.0%) reduction of the cyst excretion until at least 4 weeks after treatment. Furthermore, there was a noticeable improvement of the clinical symptoms in all animals towards day 28 after treatment and 4 months after treatment health in all calves was normal.

  12. Spatial and temporal distribution of Cryptosporidium and Giardia in a drinking water resource: Implications for monitoring and risk assessment

    Energy Technology Data Exchange (ETDEWEB)

    Burnet, Jean-Baptiste, E-mail: jeanbaptiste.burnet@gmail.com [Centre de Recherche Public - Gabriel Lippmann, Department of Environment and Agro-biotechnologies (EVA), 41, rue du Brill, L-4422 Belvaux (Luxembourg); Université de Liège (ULg), Department of Environmental Sciences and Management, 165 avenue de Longwy, B-6700 Arlon (Belgium); Penny, Christian, E-mail: penny@lippmann.lu [Centre de Recherche Public - Gabriel Lippmann, Department of Environment and Agro-biotechnologies (EVA), 41, rue du Brill, L-4422 Belvaux (Luxembourg); Ogorzaly, Leslie, E-mail: ogorzaly@lippmann.lu [Centre de Recherche Public - Gabriel Lippmann, Department of Environment and Agro-biotechnologies (EVA), 41, rue du Brill, L-4422 Belvaux (Luxembourg); Cauchie, Henry-Michel, E-mail: cauchie@lippmann.lu [Centre de Recherche Public - Gabriel Lippmann, Department of Environment and Agro-biotechnologies (EVA), 41, rue du Brill, L-4422 Belvaux (Luxembourg)

    2014-02-01

    Because of their significant public health impact, waterborne Cryptosporidium and Giardia have been monitored in surface water in order to assess microbial quality of water bodies used for drinking water production and/or for recreational purposes. In this context, sampling strategy is of key importance and should be representative enough to appropriately assess the related microbial risk. This, however, requires sound knowledge on the behaviour of both pathogens in water. In the present study, the spatial and temporal distribution of Cryptosporidium and Giardia was explored in the rural Upper-Sûre watershed used for drinking water production in Luxembourg. By subdividing it into three compartments including (i) sub-catchments, (ii) the Sûre River fed by the sub-catchments and (iii) the Upper-Sûre reservoir fed by the Sûre River, parasite distribution was assessed using sampling designs adapted to the hydro-dynamic characteristics of the respective compartments. Results highlighted the high spatial and temporal variability in parasite distribution at watershed scale, as well as the prevalence of Giardia over Cryptosporidium. Besides land use features and catchment characteristics, hydro-climatology appeared to be a major driver of parasite behaviour in the watershed. It introduced a seasonal trend in their occurrence, highest densities being detected during the wet season. Peaks of contamination triggered out by rainfall-induced runoff were further observed in the three compartments. In the Sûre River, Cryptosporidium and Giardia fluxes peaked at 10{sup 9} and 10{sup 10} (oo)cysts.d{sup −1}, respectively, and were discharged into the drinking water reservoir, where they underwent a 2 to 3 log{sub 10} removal rate. Despite this, parasite fluxes entering the drinking water treatment plant were still high (10{sup 6} to 10{sup 7} (oo)cysts.d{sup −1}) and stressed on the need for improved watershed management upstream the water treatment barrier. The catchment

  13. Spatial and temporal distribution of Cryptosporidium and Giardia in a drinking water resource: Implications for monitoring and risk assessment

    International Nuclear Information System (INIS)

    Burnet, Jean-Baptiste; Penny, Christian; Ogorzaly, Leslie; Cauchie, Henry-Michel

    2014-01-01

    Because of their significant public health impact, waterborne Cryptosporidium and Giardia have been monitored in surface water in order to assess microbial quality of water bodies used for drinking water production and/or for recreational purposes. In this context, sampling strategy is of key importance and should be representative enough to appropriately assess the related microbial risk. This, however, requires sound knowledge on the behaviour of both pathogens in water. In the present study, the spatial and temporal distribution of Cryptosporidium and Giardia was explored in the rural Upper-Sûre watershed used for drinking water production in Luxembourg. By subdividing it into three compartments including (i) sub-catchments, (ii) the Sûre River fed by the sub-catchments and (iii) the Upper-Sûre reservoir fed by the Sûre River, parasite distribution was assessed using sampling designs adapted to the hydro-dynamic characteristics of the respective compartments. Results highlighted the high spatial and temporal variability in parasite distribution at watershed scale, as well as the prevalence of Giardia over Cryptosporidium. Besides land use features and catchment characteristics, hydro-climatology appeared to be a major driver of parasite behaviour in the watershed. It introduced a seasonal trend in their occurrence, highest densities being detected during the wet season. Peaks of contamination triggered out by rainfall-induced runoff were further observed in the three compartments. In the Sûre River, Cryptosporidium and Giardia fluxes peaked at 10 9 and 10 10 (oo)cysts.d −1 , respectively, and were discharged into the drinking water reservoir, where they underwent a 2 to 3 log 10 removal rate. Despite this, parasite fluxes entering the drinking water treatment plant were still high (10 6 to 10 7 (oo)cysts.d −1 ) and stressed on the need for improved watershed management upstream the water treatment barrier. The catchment-wide analysis described here

  14. THE EFFICIENCY OF YARN WOUND FILTERS IN GIARDIA CYSTS REMOVAL USING THE IMPROVED SUCROSE GRADIENT

    Directory of Open Access Journals (Sweden)

    M.R SHAH MANSOURI

    2001-09-01

    Full Text Available Introduction. The protozoan parasite Giardia is one of the important biological cotaminants in water. lts presence in water has caused the outbreak of a number of epidemics in various part of the world including the United States. The major impediment in detecting this particular parasite is unavailability of suitable filters capable of removing it from water. Regarding the fact yarn wound filters (cartridge used in removing Giardia under laboratory condition are currently difficult to obtain in Iran, attempts were made to design and manufacture the filters according to standards recommended in the literature. Methods. To determine the efficiency of filters manufactured in this way, a pilot system was established and parameters of concern were investigated. A given number of cysts were introduced in each case to the water in the pilot tank after being counted on the hemocytometer lamella After the entire tank water (at least 4001had been pumped through the filters, the filter were removed from the pilot system to have their yarns separated and washed. The cysts recovered were then counted and compared with the original input cysts to determine the efficiency of the filters. Formation of sediments on filters due to suspended solids in water was a great impediment in counting the cysts hidden in the sediments. To overcome this difficulty, the method of floatation in sucrose was used to remove the hidden cysts from the sediments. Regarding the morphological characteristics of the cysts, the method was also studied in terms of the sucrose film concentration and the effects of centrifugal speed and duration on the removal of cysts from sediments. Results. The results indicated an efficiency of 80.69±5.85, which was ideal for a first experience in Iran. a level of 2.5 molar of Sucrose with a duration of 10 minutes for the centrifugation time at 2,000 rpm were considered to be optimum levels to yield a certainty of 95 percent and an efficiency of

  15. Identification and molecular characterization of Cryptosporidium and Giardia in children and cattle populations from the province of Álava, North of Spain

    International Nuclear Information System (INIS)

    Cardona, Guillermo A.; Carabin, Hélène; Goñi, Pilar; Arriola, Larraitz; Robinson, Guy; Fernández-Crespo, Juan C.; Clavel, Antonio; Chalmers, Rachel M.; Carmena, David

    2011-01-01

    The prevalence of and factors associated with the protozoan enteropathogens Cryptosporidium and Giardia have been investigated in selected children and cattle populations from the province of Álava (Northern Spain). The presence of these organisms was detected in fecal samples using commercially available coproantigen-ELISA (CpAg-ELISA) and immunochromatographic (ICT) assays. A total of 327 caregivers of children participants were asked to answer questions on risk factors potentially associated to the prevalence of Cryptosporidium and Giardia, including water-use practices, water sports and contact with domestic or pet animals. Molecular analyses were conducted using a nested-PCR technique to amplify the small-subunit (SSU) rRNA gene of Cryptosporidium and the triosephosphate isomerase (tpi) gene of Giardia. Cryptosporidium oocysts and Giardia cysts were found in 3 and 16 samples using the CpAg-ELISA, and in 5 and 9 samples using the ICT test, respectively. Cryptosporidium and Giardia were also found in 7 and 17 samples by CpAg-ELISA, and 4 and 14 samples by ICT, respectively, of 227 cattle fecal samples. The overall Cryptosporidium and Giardia infection prevalences, based on a Bayesian approach accounting for the imperfect sensitivities and specificities of both diagnostic tests, were estimated to 1.0% (95% BCI: 0.2%–2.8%) and 3.1% (1.5%–5.3%) in children and 3.0% (0.5%–9.2%) and 1.4% (0.0%–6.4%) in cattle, respectively. In humans, a single Cryptosporidium isolate was characterized as C. hominis. Of seven Giardia isolates, four were identified as assemblage B, two as assemblage A-II and one was a mixed assemblage B + A-II infection. No Cryptosporidium or Giardia isolates could be obtained from cattle samples. Although limited, these results seem to suggest that cattle are unlikely to be an important reservoir of zoonotic Cryptosporidium and/or Giardia in the province of Álava.

  16. Effect of Piper betle on Giardia intestinalis infection in vivo.

    Science.gov (United States)

    Pecková, Radka; Doležal, Karel; Sak, Bohumil; Květoňová, Dana; Kváč, Martin; Nurcahyo, Wisnu; Foitová, Ivona

    2018-01-01

    Piper betle has been used as a medicinal plant in traditional medical systems throughout South and South East Asia. Experimental studies have revealed its wide and diverse biological and pharmacological effects. In this study, antigiardial activity of Piper betle was tested using experimental infections of Giardia intestinalis, the most common cause of protozoal diarrhoea worldwide, in Mongolian gerbils. Plants were extracted in water, methanol and methanol:tetrahydrofuran. Gerbils were treated for ten days intragastrically twice a day, with the dose of 40 mg of the extract per 100 g of body weight. Drug metronidazole was used as a negative control. Gerbils' faeces were taken every day and examined by flotation method, the number of shed cysts were counted using a haemocytometer. After gerbils' sacrifice and dissection, their duodena were then processed for examination using histological sectioning and scanning electron microscopy. The antigiardial activity was evaluated by the course of cyst shedding throughout the entire experiment. A significant decline in cyst shedding, evaluated by linear regression was found in gerbils treated with the aqueous extract. Our results indicate that the aqueous extract of P. betle shows giardicidal effects. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Molecular characterization of Giardia intestinalis haplotypes in marine animals: variation and zoonotic potential.

    Science.gov (United States)

    Lasek-Nesselquist, Erica; Bogomolni, Andrea L; Gast, Rebecca J; Welch, David Mark; Ellis, Julie C; Sogin, Mitchell L; Moore, Michael J

    2008-08-19

    Giardia intestinalis is a microbial eukaryotic parasite that causes diarrheal disease in humans and other vertebrates worldwide. The negative effect on quality of life and economics caused by G. intestinalis may be increased by its potential status as a zoonosis, or a disease that can be transmitted from animals to humans. The zoonotic potential of G. intestinalis has been implied for over 2 decades, with human-infecting genotypes (belonging to the 2 major subgroups, Assemblages A and B) occurring in wildlife and domesticated animals. There are recent reports of G. intestinalis in shellfish, seals, sea lions and whales, suggesting that marine animals are also potential reservoirs of human disease. However, the prevalence, genetic diversity and effect of G. intestinalis in marine environments and the role that marine animals play in transmission of this parasite to humans are relatively unexplored. Here, we provide the first thorough molecular characterization of G. intestinalis in marine vertebrates. Using a multi-locus sequencing approach, we identify human-infecting G. intestinalis haplotypes of both Assemblages A and B in the fecal material of dolphins, porpoises, seals, herring gulls Larus argentatus, common eiders Somateria mollissima and a thresher shark Alopias vulpinus. Our results indicate that G. intestinalis is prevalent in marine ecosystems, and a wide range of marine hosts capable of harboring zoonotic forms of this parasite exist. The presence of G. intestinalis in marine ecosystems raises concerns about how this disease might be transmitted among different host species.

  18. A new quantitative in vitro microculture method for Giardia duodenalis trophozoites.

    Science.gov (United States)

    Bénéré, Ely; da Luz, Raquel Andreia Inocêncio; Vermeersch, Marieke; Cos, Paul; Maes, Louis

    2007-11-01

    A reliable, rapid and low-cost method for drug sensitivity determination of Giardia duodenalis trophozoites (WB-strain) was developed in a 96-well plate. Using a standard inoculum of 5 x 10(4) trophozoites per well (300 microl), good growth was obtained after sealing the plate with an air-tight adhesive tape and incubation at 37 degrees C for 72 h in modified TYI-S-33 medium. Viable burdens were quantified using the formazan dyes MTT (100 microg/well) and XTT (20 microg/well) and the fluorescent substrate resazurin (2.5 microg/well). Prior removal of the culture medium is required since it causes spontaneous reduction of the substrate. Resazurin proved to be far superior to MTT and XTT with a level of sensitivity of about 3 x 10(4) trophozoites. Inhibitory concentrations (IC(50)) of several anti-giardial reference drugs were within the range of published values: metronidazole 2.25 microM, tinidazole 1.75 microM, albendazole 0.10 microM, furazolidone 2.00 microM and quinacrine 0.32 microM. The broad-spectrum antibiotics chloramphenicol, rifampicin, penicillin G+streptomycin and gentamycin were devoid of any inhibitory activity and are considered suitable for decontamination during excystation experiments.

  19. First genotyping of Giardia duodenalis and prevalence of enteroparasites in children from Tetouan (Morocco

    Directory of Open Access Journals (Sweden)

    El Fatni Chadia

    2014-01-01

    Full Text Available Intestinal parasites are common in the Moroccan population. Enteroparasites in children from four schools in urban and rural areas of Tetouan (Morocco were studied to treat these children and to design prevention and control programs. A total of 673 children were examined. The prevalence of parasitized children was 51%. The average number of enteroparasites was half in urban areas than in rural areas. Multiple parasitism appeared in 30% of the samples presenting two, three, or four parasites. The most prevalent parasite was Blastocystis hominis (64%. Giardia duodenalis was the most frequent pathogen, with an overall prevalence of 20% (24% in rural areas and 16% in urban areas. Other pathogenic enteroparasites were Cyclospora cayetanensis (5% in rural and urban areas, Iodamoeba butschlii, Hymenolepis spp., Trichuris trichiura and Enterobius vermicularis, with prevalence lower than 2%. In this work, G. duodenalis genotypes were molecularly characterized by a study of the glutamate dehydrogenase (gdh and 18S rRNA genes. This is the first study of molecular characterization of G. duodenalis in Moroccan children, and the sequence analysis revealed both Assemblage A (AII and Assemblage B (BIII, BIV, with the predominance of Assemblage BIV (73%.

  20. Phagocytosis of Giardia muris by macrophages in Peyer's patch epithelium in mice.

    Science.gov (United States)

    Owen, R L; Allen, C L; Stevens, D P

    1981-08-01

    No mechanism for the initiation of immunological clearance of Giardia from the mammalian intestinal tract has been identified. In normal and nude mice experimentally infected with G. muris, we examined antigen-sampling epithelium over Peyer's patch follicles by electron microscopy for evidence of interaction between G. muris and lymphoid cells. Invading G. muris were found in the epithelium near dying or desquamating columnar cells. Macrophages beneath the basal lamina extended pseudopods into the epithelium, trapping invading G. muris and enclosing them in phagolysosomes. In normal mice, which clear G. muris in 4 to 6 weeks, macrophages containing digested G. muris were surrounded by rosettes of lymphoblasts in the epithelium. In nude mice deficient in lymphocytes, there was apparent hyperplasia of macrophages, which filled the follicle domes, resulting in more frequent entrapment of G. muris but no contact between macrophages and lymphoblasts in the epithelium. In nude mice, which require 6 months to control G. muris infection, lymphoblast contact with macrophages containing distinctive microtubular remnants of G. muris was only identified in the follicle dome. This close physical association of lymphoblasts and macrophages containing G. muris remnants suggests that this macrophage activity represents intraepithelial antigen processing as well as a defense against the effects of the uncontrolled entrance of microorganisms and other antigenic particles into Peyer's patch lymphoid follicles.

  1. [Giardia muris infection in laboratory rats (Rattus norvegicus) and treatment with metronidazole].

    Science.gov (United States)

    Beyhan, Yunus Emre; Hökelek, Murat

    2014-01-01

    This study was conducted to determine the effectiveness of metronidazole for treatment of Giardia muris infection in laboratory rats. The feces of rats was yellow watery diarrhea and brought to the surgery research center of University of Ondokuz Mayis in order to be a study. Stool samples were examined by native examination, evaluation of infection rates was done with an X40 lens, and results were recorded as positive from 1 to 4. Metronidazole was administered to infected animals orally for 5 days with a 20 mg/kg dose. As a result of fecal examination of 64 rats held in groups of four in cages, 15 of the cages (60 rats) were found to be infected with G. muris. While agents were not observed in collected stool samples following 5, 7, and 14 days of drug administration of 14 groups, trophozoite density in one cage was decreased (75%), and adverse effects were not seen in rats. Metronidazole was found to be an effective drug for the treatment of giardiasis.

  2. Characterization and separation of Cryptosporidium and Giardia cells using on-chip dielectrophoresis.

    Science.gov (United States)

    Narayanan Unni, Harikrishnan; Hartono, Deny; Yue Lanry Yung, Lin; Mah-Lee Ng, Mary; Pueh Lee, Heow; Cheong Khoo, Boo; Lim, Kian-Meng

    2012-03-01

    Dielectrophoresis (DEP) has been shown to have significant potential for the characterization of cells and could become an efficient tool for rapid identification and assessment of microorganisms. The present work is focused on the trapping, characterization, and separation of two species of Cryptosporidium (C. parvum and C. muris) and Giardia lambia (G. lambia) using a microfluidic experimental setup. Cryptosporidium oocysts, which are 2-4 μm in size and nearly spherical in shape, are used for the preliminary stage of prototype development and testing. G. lambia cysts are 8-12 μm in size. In order to facilitate effective trapping, simulations were performed to study the effects of buffer conductivity and applied voltage on the flow and cell transport inside the DEP chip. Microscopic experiments were performed using the fabricated device and the real part of Clausius-Mossotti factor of the cells was estimated from critical voltages for particle trapping at the electrodes under steady fluid flow. The dielectric properties of the cell compartments (cytoplasm and membrane) were calculated based on a single shell model of the cells. The separation of C. muris and G. lambia is achieved successfully at a frequency of 10 MHz and a voltage of 3 Vpp (peak to peak voltage).

  3. Coinfection with Tritrichomonas foetus and Giardia duodenalis in Two Cats with Chronic Diarrhea

    Directory of Open Access Journals (Sweden)

    Sergio A. Zanzani

    2016-01-01

    Full Text Available A Tritrichomonas foetus and Giardia duodenalis mixed infection was diagnosed in two Maine Coon cats aged six months. One of them presented a history of chronic liquid diarrhea and of several unsuccessful treatments. In both cats, G. duodenalis and trichomonads were detected in fecal smears from freshly voided feces; the presence of T. foetus was confirmed by a real-time PCR assay. The cats completely recovered after treatment with ronidazole. In a refrigerated fecal sample collected from the cat with chronic diarrhea, drop-shaped trichomonad pseudocysts smaller than G. duodenalis cysts were detected. They appeared brownish or light-bluish when stained with Lugol’s solution or with Giemsa stain, respectively, and their morphological features were similar to those expressed by bovine T. foetus pseudocysts in vitro. Existence of pseudocysts even in feline trichomonads is noteworthy as they could represent a form of protozoan resistance due to unfavorable conditions whose detection in refrigerated feces can be a useful clue for clinicians.

  4. Deconjugated bile salts produced by extracellular bile-salt hydrolase-like activities from the probiotic Lactobacillus johnsonii La1 inhibit Giardia duodenalis in vitro growth

    Directory of Open Access Journals (Sweden)

    Marie-Agnès Travers

    2016-09-01

    Full Text Available Giardiasis, currently considered a neglected disease, is caused by the intestinal protozoan parasite Giardia duodenalis and is widely spread in human as well as domestic and wild animals. The lack of appropriate medications and the spread of resistant parasite strains urgently call for the development of novel therapeutic strategies. Host microbiota or certain probiotic strains have the capacity to provide some protection against giardiasis. By combining biological and biochemical approaches, we have been able to decipher a molecular mechanism used by the probiotic strain Lactobacillus johnsonii La1 to prevent Giardia growth in vitro. We provide evidence that the supernatant of this strain contains active principle(s not directly toxic to Giardia but able to convert non-toxic components of bile into components highly toxic to Giardia. By using bile acid profiling, these components were identified as deconjugated bile-salts. A bacterial bile-salt-hydrolase of commercial origin was able to mimic the properties of the supernatant. Mass spectrometric analysis of the bacterial supernatant identified two of the three bile-salt-hydrolases encoded in the genome of this probiotic strain. These observations document a possible mechanism by which L. johnsonii La1, by secreting or releasing BSH-like activity(ies in the vicinity of replicating Giardia in an environment where bile is present and abundant, can fight this parasite. This discovery has both fundamental and applied outcomes to fight giardiasis, based on local delivery of deconjugated bile salts, enzyme deconjugation of bile components, or natural or recombinant probiotic strains that secrete or release such deconjugating activities in a compartment where both bile salts and Giardia are present.

  5. Análisis bibliométrico de la literatura científica sobre epidemiología de Giardia en Argentina (1995-2014)

    OpenAIRE

    Molina, Nora Beatriz; Grenóvero, María Silvia; Bertucci, Evangelina; Basualdo Farjat, Juan A.; Basualdo Farjat, Juan Ángel

    2015-01-01

    Las publicaciones sobre la epidemiología de Giardia en humanos de Argentina se hallan dispersas en numerosas fuentes de información, lo que dificulta su acceso y visibilidad para la comunidad científica. El objetivo de este trabajo fue realizar un análisis bibliométrico cuantitativo de la producción científica sobre Giardia en humanos de Argentina durante el período 1995-2014. El volumen de publicaciones científicas hallado fue igual a 112 (36 artículos, 73 comunicaciones y 3 tesis). La distr...

  6. Prevalence and molecular characterization of Cryptosporidium spp. and Giardia duodenalis in deer in Henan and Jilin, China.

    Science.gov (United States)

    Huang, Jianying; Zhang, Zhenjie; Zhang, Yiqi; Yang, Yong; Zhao, Jinfeng; Wang, Rongjun; Jian, Fuchun; Ning, Changshen; Zhang, Wanyu; Zhang, Longxian

    2018-04-12

    Little is known about the prevalence and zoonotic potential of Cryptosporidium spp. and Giardia duodenalis in deer in China. In this study, 662 fecal samples were collected from 11 farms in Henan and Jilin Provinces between July 2013 and August 2014, and were screened for the presence of Cryptosporidium and G. duodenalis with genotyping and subtyping methods. Cryptosporidium spp. and G. duodenalis were detected in 6.80% (45/662) and 1.21% (5/662) of samples, respectively. Six Cryptosporidium species/genotypes were identified based on the small subunit ribosomal ribonucleic acid (SSU rRNA) gene: C. parvum (n = 11); C. andersoni (n = 5); C. ubiquitum (n = 3); C. muris (n = 1); C. suis-like (n = 1); and Cryptosporidium deer genotype (n = 24). When five of the 11 C. parvum isolates were subtyped by sequencing the 60 kDa glycoprotein (gp60) gene, zoonotic subtypes IIaA15G2R2 (n = 4) and IIdA19G1 (n = 1) were found. According to a subtype analysis, three C. ubiquitum isolates belonged to XIIa subtype 2. In contrast, only assemblage E was detected in the five Giardia-positive samples with small subunit ribosomal ribonucleic acid (SSU rRNA) gene sequencing. To our knowledge, this is the first study to report C. andersoni, as well as C. parvum zoonotic subtypes IIaA15G2R2 and IIdA19G1 in cervids. These data, though limited, suggest that cervids may be a source of zoonotic Cryptosporidium and Giardia. Cervids in the present study are likely to be of low zoonotic potential to humans, and more molecular epidemiological studies are required to clarify the prevalence and public health significance of Cryptosporidium and G. duodenalis in cervids throughout China.

  7. Oral immunization of BALB/c mice with Giardia duodenalis recombinant cyst wall protein inhibits shedding of cysts.

    Science.gov (United States)

    Larocque, R; Nakagaki, K; Lee, P; Abdul-Wahid, A; Faubert, G M

    2003-10-01

    The process of encystation is a key step in the Giardia duodenalis life cycle that allows this intestinal protozoan to survive between hosts during person-to-person, animal-to-person, waterborne, or food-borne transmission. The release of cysts from infected persons and animals is the main contributing factor to contamination of the environment. Genes coding for cyst wall proteins (CWPs), which could be used for developing a transmission-blocking vaccine, have been cloned. Since the immunogenicity of recombinant Giardia CWP is unknown, we have investigated the immunogenicity of recombinant CWP2 (rCWP2) and its efficacy in interfering with the phenomenon of encystation taking place in the small bowels of BALB/c mice vaccinated with the recombinant protein. Here we report that the immunization of BALB/c mice with rCWP2 stimulated the immune system in a manner comparable to that for a live infection with Giardia muris cysts. Fecal and serum anti-rCWP2 immunoglobulin A (IgA) antibodies were detected in the immunized mice. In addition, anti-rCWP2 IgG1 and IgG2a antibodies were detected in the serum. mRNAs coding for Th1 and Th2 types of cytokines were detected in spleen and Peyer's patch cells from immunized mice. When the vaccinated mice were challenged with live cysts, the animals shed fewer cysts. We conclude that rCWP2 is a possible candidate antigen for the development of a transmission-blocking vaccine.

  8. Jejunal brush border microvillous alterations in Giardia muris-infected mice: role of T lymphocytes and interleukin-6.

    Science.gov (United States)

    Scott, K G; Logan, M R; Klammer, G M; Teoh, D A; Buret, A G

    2000-06-01

    Intestinal colonization with the protozoan Giardia causes diffuse brush border microvillous alterations and disaccharidase deficiencies, which in turn are responsible for intestinal malabsorption and maldigestion. The role of T cells and/or cytokines in the pathogenesis of Giardia-induced microvillous injury remains unclear. The aim of this study was to assess the role of T cells and interleukin-6 (IL-6) in the brush border pathophysiology of acute murine giardiasis in vivo. Athymic nude (nu(-)/nu(-)) CD-1 mice and isogenic immunocompetent (nu(+)/nu(+)) CD-1 mice (4 weeks old) received an axenic Giardia muris trophozoite inoculum or vehicle (control) via orogastric gavage. Weight gain and food intake were assessed daily. On day 6, segments of jejunum were assessed for parasite load, brush border ultrastructure, IL-6 content, maltase and sucrase activities, villus-crypt architecture, and intraepithelial lymphocyte (IEL) infiltration. Despite similar parasitic loads on day 6, infected immunocompetent animals, but not infected nude mice, showed a diffuse loss of brush border microvillous surface area, which was correlated with a significant reduction in maltase and sucrase activities and a decrease in jejunal IL-6 concentration. In both athymic control and infected mice, jejunal brush border surface area and disaccharidases were high, but levels of tissue IL-6 were low and comparable to the concentration measured in immunocompetent infected animals. In both immunocompetent and nude mice, infection caused a small but significant increase in the numbers of IELs. These findings suggest that the enterocyte brush border injury and malfunction seen in giardiasis is, at least in part, mediated by thymus-derived T lymphocytes and that suppressed jejunal IL-6 does not necessarily accompany microvillous shortening.

  9. Cryptosporidium spp. and Giardia spp. in feces and water and the associated exposure factors on dairy farms.

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    Roberta Dos Santos Toledo

    Full Text Available The aims of this study were to verify the prevalence of Cryptosporidium spp. and Giardia spp. in animal feces and drinking water on dairy farms and to identify a possible relation between the exposure factors and the presence of these parasites. Fecal samples from cattle and humans and water samples were collected on dairy farms in Paraná, Brazil. Analysis of (oocysts in the feces was performed by the modified Ziehl-Neelsen staining and centrifugal flotation in zinc sulfate. Test-positive samples were subjected to nested PCR amplification of the 18SSU ribosomal RNA gene for identification of Cryptosporidium and Giardia and of the gp60 gene for subtyping of Cryptosporidium. Microbiological analysis of water was carried out by the multiple-tube method and by means of a chromogenic substrate, and parasitological analysis was performed on 31 samples by direct immunofluorescence and nested PCR of the genes mentioned above. Identification of the species of Cryptosporidium was performed by sequencing and PCR with analysis of restriction fragment length polymorphisms. The prevalence of Giardia and Cryptosporidium was higher in calves than in adults. Among the samples of cattle feces, Cryptosporidium parvum was identified in 41 (64%, C. ryanae in eight (12.5%, C. bovis in four (6.3%, C. andersoni in five (7.8%, and a mixed infection in 20 samples (31.3%. These parasites were not identified in the samples of human feces. Thermotolerant coliform bacteria were identified in 25 samples of water (45.5%. Giardia duodenalis and C. parvum were identified in three water samples. The gp60 gene analysis of C. parvum isolates revealed the presence of two strains (IIaA20G1R1 and IIaA17G2R2 in the fecal samples and one (IIaA17G2R1 in the water samples. The presence of coliforms was associated with the water source, structure and degradation of springs, rain, and turbidity. The prevalence of protozoa was higher in calves up to six months of age. C. parvum and G

  10. Checking the detail in retail: Occurrence of Cryptosporidium and Giardia on vegetables sold across different counters in Chandigarh, India.

    Science.gov (United States)

    Utaaker, Kjersti Selstad; Kumar, Anil; Joshi, Himanshu; Chaudhary, Suman; Robertson, Lucy J

    2017-12-18

    Fresh produce has been recognized as a vehicle of infection for protozoan parasites, particularly Cryptosporidium, and, to a lesser extent, Giardia. For both parasites, outbreaks associated with fresh produce have been documented. Although documented outbreaks tend to be from industrialized countries, contamination of fresh produce with these parasites is a global issue. In developing countries, infections with these parasites are often endemic in the community, and basic infrastructure and hygiene measures may be inadequate, thus the likelihood of contamination of fresh produce with these parasites may be higher. Realization of the importance of this transmission route comes against a backdrop of raw salads and more Western culinary habits gaining a foothold, and fresh produce being encouraged as part of the diet due to their associated health benefits. However, if consumption of uncooked fresh produce is going to increase its market sector in India, it is important that it is safe. In this study, various types of fresh produce obtained from three types of vendors in Chandigarh, a major city in Northern India, were analyzed for contamination with Cryptosporidium oocysts and Giardia cysts using a method that has been previously validated in inter-laboratory spiking experiments. A total of 284 samples of different fresh produce items were analyzed, obtained from the different retailers situated in different societal layers of the city. The overall prevalence of contamination of fresh produce with these parasites was just under 11%, with 6% of the vegetables contaminated with Cryptosporidium oocysts, and 5% with Giardia cysts. Contaminated vegetables included turnip, cabbage, carrot, chili, coriander, cucumber, radishes, and tomatoes. Molecular analyses identified contamination with Cryptosporidium parvum and Giardia duodenalis of Assemblage A and Assemblage D, indicating that contamination from animals may be of relevance. Although the prevalence of contamination is

  11. Efficacy and security of ivermectin given orally to rats naturally infected with Syphacia spp., Giardia spp. and Hymenolepis nana.

    Science.gov (United States)

    Foletto, V R S; Vanz, F; Gazarini, L; Stern, C A J; Tonussi, C R

    2015-07-01

    The results of this study show that the oral administration of ivermectin (48 mg/L) repeatedly for 72 h used in accordance with the present protocol is a safe and highly effective treatment for Giardia spp. and Hymenolepis nana in laboratory rat colonies. The drug can be easily and safely administered using drinking water. This simple regimen should control pinworm infection (Syphacia muris), a problem that can be endemic in laboratory colonies. Experiments using healthy animals are likely to generate more consistent results, thereby requiring a reduced number of animals per group. © The Author(s) 2014.

  12. Spatial and temporal distribution of Cryptosporidium and Giardia in a drinking water resource: implications for monitoring and risk assessment.

    Science.gov (United States)

    Burnet, Jean-Baptiste; Penny, Christian; Ogorzaly, Leslie; Cauchie, Henry-Michel

    2014-02-15

    Because of their significant public health impact, waterborne Cryptosporidium and Giardia have been monitored in surface water in order to assess microbial quality of water bodies used for drinking water production and/or for recreational purposes. In this context, sampling strategy is of key importance and should be representative enough to appropriately assess the related microbial risk. This, however, requires sound knowledge on the behaviour of both pathogens in water. In the present study, the spatial and temporal distribution of Cryptosporidium and Giardia was explored in the rural Upper-Sûre watershed used for drinking water production in Luxembourg. By subdividing it into three compartments including (i) sub-catchments, (ii) the Sûre River fed by the sub-catchments and (iii) the Upper-Sûre reservoir fed by the Sûre River, parasite distribution was assessed using sampling designs adapted to the hydro-dynamic characteristics of the respective compartments. Results highlighted the high spatial and temporal variability in parasite distribution at watershed scale, as well as the prevalence of Giardia over Cryptosporidium. Besides land use features and catchment characteristics, hydro-climatology appeared to be a major driver of parasite behaviour in the watershed. It introduced a seasonal trend in their occurrence, highest densities being detected during the wet season. Peaks of contamination triggered out by rainfall-induced runoff were further observed in the three compartments. In the Sûre River, Cryptosporidium and Giardia fluxes peaked at 10(9) and 10(10) (oo)cysts.d(-1), respectively, and were discharged into the drinking water reservoir, where they underwent a 2 to 3 log10 removal rate. Despite this, parasite fluxes entering the drinking water treatment plant were still high (10(6) to 10(7) (oo)cysts.d(-1)) and stressed on the need for improved watershed management upstream the water treatment barrier. The catchment-wide analysis described here

  13. Iodine Disinfection in the Use of Individual Water Purification Devices

    Science.gov (United States)

    2006-03-01

    Effect of Resin Disinfectants-I3 and –I5 on Giardia muris and Giardia lamblia. Applied and Environmental Microbiology, 46(5), 965-969. 24. AWWA... Giardia or Cryptosporidium). Iodine-using IWPDs meeting these standards are considered effective against disease causing bacteria, viruses, and...CT = 65 mg-min/L) for a 2-log inactivation of E. histolytica cysts (references 9 and 10). Another study using Giardia cysts showed CT’s up to 3

  14. Ultraviolet Light Disinfection in the Use of Individual Water Purification Devices

    Science.gov (United States)

    2006-03-01

    adenovirus, Giardia lamblia, Giardia muris , and Cryptosporidium parvum. Adenovirus was evaluated because it is considered the most resistant to...7 reproduce cannot infect and are thereby inactivated. Subsequently, when evaluating UV disinfection capability, Giardia cyst and...0.25 to 20 NTU resulted in a 0.8-log and 0.5-log decrease in inactivation of Cryptosporidium and Giardia , respectively (reference 3). The type of

  15. Long-Term Survival of Enteric Microorganisms in Frozen Wastewater

    Science.gov (United States)

    2002-10-01

    sewage.............31 Table 12. Percentage of cysts of Giardia muris recovered after one and three cycles of freezing and thawing...of Giardia muris and Giardia lamblia that had been subjected to one to three cycles of freezing at –16°C and thawing at 20°C. Examination Long-Term... Giardia muris recovered after one and three cycles of freezing and thawing. (From Erlandsen et al. 1990.)a Number of freeze–thaw cycles Initial

  16. Giardiasis in mice: analysis of humoral and cellular immune responses to Giardia muris.

    Science.gov (United States)

    Anders, R F; Roberts-Thomson, I C; Mitchell, G F

    1982-01-01

    Humoral and cellular immune responses have been evaluated in two inbred strains of mice which differ markedly in their susceptibility to infection with Giardia muris. Serum IgG and IgA antibody levels and IgA levels in intestinal washes were determined by a solid-phase radioimmunoassay using G. muris antigen prepared by sonication of trophozoites, while cell-mediated immunity was assessed by a radiometric ear-assay for delayed-type hypersensitivity. Following infection of BALB/c mice (resistant) and C3H/He mice (susceptible), the IgG and IgA antibody levels in serum progressively increased over the period of study with C3H/He mice having significantly higher titres of IgA antibodies than BALB/c late in the infection. Systemic immunization with G. muris trophozoites resulted in high titres of IgG antibodies in the serum. IgA antibodies were detected in intestinal washes 2 weeks after infection with a subsequent fall in levels in BALB/c mice but a progressive increase levels in C3H/He mice. Prior immunization resulted in IgA antibodies being detected earlier in the intestinal washings after a challenge infection. Delayed-type hypersensitivity to G. muris antigens could not be detected during an infection but a positive response was elicited following antigen priming in mice pretreated with cyclophosphamide. The immune responses evaluated in this study were assessed using a whole G. muris trophozoite sonicate and variations in the quantitative aspects of the responses did not account for observed differences in the course of infection in the two strains of mice.

  17. Synergistic effects of fenbendazole and metronidazole against Giardia muris in Swiss mice naturally infected.

    Science.gov (United States)

    Bezagio, Renata Coltro; Colli, Cristiane Maria; Romera, Liara Izabela Lopes; Ferreira, Érika Cristina; Falavigna-Guilherme, Ana Lúcia; Gomes, Mônica Lúcia

    2017-03-01

    In this study were proposed different protocols for the treatment of mice naturally infected with Giardia muris. Male Swiss mice were divided into seven groups, with five animals each, in a blind, controlled, randomized by drawing lots and once-repeated experiment. Parasite detection and cure control were performed using the Faust method and search by trophozoites in the intestinal mucosa. Clinical parameters (weight, water and feed consumption, elimination of excreta, aspect of the fur and feces) were also evaluated. All animals were treated with metronidazole (M), fenbendazole (F), and probiotics (P), administered intragastrically, during 7 days. M1, FM1, and F1 groups were treated 1×/day; M3, FM3, and PM3 groups 3×/day; and ST (control group) received only water. After the 5th and 7th days of treatment, the animals in FM1/FM3 and PM3/M3 groups presented, respectively, negative results and remained negative in the following 10 days. Animals in F1 group consumed less water (p = 0.00010) compared with FM1/FM3/PM3. The animals in M1 group compared with FM3/M3, F1 compared with M3, and ST compared with FM1/FM3/M3/PM3 consumed a larger amount of feed (p = 0.00001). The animals in F1 group compared with FM3/M1/M3/PM3, FM1 compared with FM3, and ST compared with FM3/M1/M3/PM3 eliminated lower volume of excreta (p = 0.00001). The results show that the association between F and M potentiates the effects, indicating a synergistic action of these two drugs, and FM1 is the best protocol due to early negativity in the animals, lower concentrations of the drugs, lower risk of toxicity and stress, and less alterations in clinical parameters.

  18. Effectiveness of ceramic filters in capturing Giardia duodenalis cysts in experimentally contaminated water

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    Larissa Imaculada da Costa Sobrinho

    2016-04-01

    Full Text Available Giardia duodenalis is the main water-transmitted protozoan in developing countries. This study evaluated the effectiveness of ceramic filters in capturing G. duodenalis cysts and verified the porosity size needed to remove cysts from contaminated water. The study was conducted in the Laboratory of Parasitology at the University of Taubaté, where each filter unit was made by joining two Pet gallons, latex hose and a ceramic filter. Two porosity sizes were selected: 0.5-1.0 μm and 5-15 μm with or without activated carbon, and the assays were run in triplicate. Approximately 60 μL (53 cysts of G. duodenalis cysts were placed in 2 liters of distilled water. After the preparation of the contaminated water, this solution was run through the filter until the completely filtered. Afterwards, the filtrate was processed according to the methodology described by De Faria (2006, in order to concentrate parasitic elements. The results were statistically evaluated using ANOVA and Tukey tests, showing that the 0.5- 1,0 μm porosity filter candles (with and without activated carbon were able to retain 100% of cysts of G. duodenalis. This is a result significantly superior to the results obtained in the control group (p<0.05. On the other hand, for the candles with porosity of 5 15 μm, total retention occurred only in candles with activated carbon. Based upon our results, it can be concluded that, in candles with both porosity sizes with activated carbon, all filters showed a satisfactory efficacy for filtration of G. duodenalis cysts.

  19. Isolation and Antimicrobial Susceptibility Profile of Shigella and ...

    African Journals Online (AJOL)

    2018-03-01

    Mar 1, 2018 ... species, Vibrio cholera, Yersinia enterocolitica, and Aeromonas species), enteroparasites (Giardia lamblia, Cryptosporidium species and Entamoeba histolytica), and viruses (adenovirus, Norwalk virus, and rotavirus) (5). Among the bacterial causative agents,. Salmonella and Shigella remain the major.

  20. Giardia duodenalis Surface Cysteine Proteases Induce Cleavage of the Intestinal Epithelial Cytoskeletal Protein Villin via Myosin Light Chain Kinase.

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    Amol Bhargava

    Full Text Available Giardia duodenalis infections are among the most common causes of waterborne diarrhoeal disease worldwide. At the height of infection, G. duodenalis trophozoites induce multiple pathophysiological processes within intestinal epithelial cells that contribute to the development of diarrhoeal disease. To date, our understanding of pathophysiological processes in giardiasis remains incompletely understood. The present study reveals a previously unappreciated role for G. duodenalis cathepsin cysteine proteases in intestinal epithelial pathophysiological processes that occur during giardiasis. Experiments first established that Giardia trophozoites indeed produce cathepsin B and L in strain-dependent fashion. Co-incubation of G. duodenalis with human enterocytes enhanced cathepsin production by Assemblage A (NF and S2 isolates trophozoites, but not when epithelial cells were exposed to Assemblage B (GSM isolate trophozoites. Direct contact between G. duodenalis parasites and human intestinal epithelial monolayers resulted in the degradation and redistribution of the intestinal epithelial cytoskeletal protein villin; these effects were abolished when parasite cathepsin cysteine proteases were inhibited. Interestingly, inhibition of parasite proteases did not prevent degradation of the intestinal tight junction-associated protein zonula occludens 1 (ZO-1, suggesting that G. duodenalis induces multiple pathophysiological processes within intestinal epithelial cells. Finally, this study demonstrates that G. duodenalis-mediated disruption of villin is, at least, in part dependent on activation of myosin light chain kinase (MLCK. Taken together, this study indicates a novel role for parasite cathepsin cysteine proteases in the pathophysiology of G. duodenalis infections.

  1. Dientamoeba fragilis is more prevalent than Giardia duodenalis in children and adults attending a day care centre in Central Italy

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    Crotti D.

    2005-06-01

    Full Text Available Giardia duodenalis is a well recognised enteropathogen, while Dientamoeba fragilis is rarely detected and consequently it is not recognised as an important human pathogen. In 2002-2003, a survey has been carried out on enteroparasites in faecal samples of outpatients attending a day care centre in the town of Perugia (Central Italy. To improve the detection level, at least three samples from each patient were collected at different days and within two hours from defecation. The coproparasitological examination has been carried out by direct microscopic examination, faecal concentration, and Giemsa and modified Ziehl-Nielsen stainings of faecal smears. The genotypes of Giardia duodenalis isolates were determined by PCR of the β-giardin gene. Of 1,989 enrolled people (966 children, 1,023 adults, 165 persons (8.3%; 153 adults, 15.0%; 12 children, 1.2%, were positive for parasites, but only 112 adults (73.2% of those infected and eight children (66.7% of those infected harboured D. fragilis and G. duodenalis. Both the Assemblages A and B were detected in 18 G. duodenalis isolates examined at the β-giardin gene. The higher prevalence of D. fragilis infections than that of G. duodenalis is probably related to the method used, a procedure, which is rarely followed in laboratories for the diagnosis of enteric parasites. These epidemiological data suggest that when faecal samples are examined after a period of time and without Giemsa staining, most D. fragilis infections goes undetected.

  2. Cryptosporidium and Giardia in Surface Water: A Case Study from Michigan, USA to Inform Management of Rural Water Systems

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    Erin A. Dreelin

    2014-10-01

    Full Text Available Cryptosporidium and Giardia pose a threat to human health in rural environments where water supplies are commonly untreated and susceptible to contamination from agricultural animal waste/manure, animal wastewater, septic tank effluents and septage. Our goals for this paper are to: (1 explore the prevalence of these protozoan parasites, where they are found, in what quantities, and which genotypes are present; (2 examine relationships between disease and land use comparing human health risks between rural and urban environments; and (3 synthesize available information to gain a better understanding of risk and risk management for rural water supplies. Our results indicate that Cryptosporidium and Giardia were more prevalent in rural versus urban environments based on the number of positive samples. Genotyping showed that both the human and animal types of the parasites are found in rural and urban environments. Rural areas had a higher incidence of disease compared to urban areas based on the total number of disease cases. Cryptosporidiosis and giardiasis were both positively correlated (p < 0.001 with urban area, population size, and population density. Finally, a comprehensive strategy that creates knowledge pathways for data sharing among multiple levels of management may improve decision-making for protecting rural water supplies.

  3. Detection of zoonotic and livestock-specific assemblages of Giardia duodenalis in free-living wild lizards

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    Aurora Reboredo-Fernández

    Full Text Available Abstract Giardia duodenalis is a zoonotic parasite that infects the gut of a wide range of vertebrates, including numerous wildlife species. However, little is known about this protozoan parasite in reptiles. Fecal samples from 31 wild lizards were collected in Galicia (northwest Spain and screened for the presence of Giardia by PCR amplification and sequencing of the ITS1-5.8S-ITS2 region in the ribosomal unit. This allowed detection of the parasite in 5 samples (16.1%, and enabled identification of G. duodenalis assemblage A2 in two samples of Iberian rock lizard (Iberolacerta monticola, G. duodenalis assemblage B in other two samples of I. monticola, and G. duodenalis assemblage E in one sample of Bocage’s wall lizard (Podarcis bocagei. The results obtained after PCR amplification and sequencing of the SSU-rDNA gene confirmed the presence of G. duodenalis assemblage A in two samples of I. monticola. This is the first report of G. duodenalis in free-living lizards, although further studies are needed to distinguish between actual infection and mechanical dissemination of cysts. The detection of zoonotic and livestock-specific assemblages of G. duodenalis demonstrates the wide environmental contamination by this parasite, possibly due to human activities.

  4. Molecular Characterization of Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi in Captive Wildlife at Zhengzhou Zoo, China.

    Science.gov (United States)

    Li, Junqiang; Qi, Meng; Chang, Yankai; Wang, Rongjun; Li, Tongyi; Dong, Haiju; Zhang, Longxian

    2015-01-01

    Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi are common gastrointestinal protists in humans and animals. Two hundred and three fecal specimens from 80 wildlife species were collected in Zhengzhou Zoo and their genomic DNA extracted. Three intestinal pathogens were characterized with a DNA sequence analysis of different loci. Cryptosporidium felis, C. baileyi, and avian genotype III were identified in three specimens (1.5%), the manul, red-crowned crane, and cockatiel, respectively. Giardia duodenalis was also found in five specimens (2.5%) firstly: assemblage B in a white-cheeked gibbon and beaver, and assemblage F in a Chinese leopard and two Siberian tigers, respectively. Thirteen genotypes of E. bieneusi (seven previously reported genotypes and six new genotypes) were detected in 32 specimens (15.8%), of which most were reported for the first time. A phylogenetic analysis of E. bieneusi showed that five genotypes (three known and two new) clustered in group 1; three known genotypes clustered in group 2; one known genotype clustered in group 4; and the remaining four genotypes clustered in a new group. In conclusion, zoonotic Cryptosporidium spp., G. duodenalis, and E. bieneusi are maintained in wildlife and transmitted between them. Zoonotic disease outbreaks of these infectious agents possibly originate in wildlife reservoirs. © 2015 The Author(s) Journal of Eukaryotic Microbiology © 2015 International Society of Protistologists.

  5. Occurrence of Giardia intestinalis and Cryptosporidium sp. in wastewater samples from São Paulo State, Brazil, and Lima, Peru.

    Science.gov (United States)

    Ulloa-Stanojlović, Francisco Miroslav; Aguiar, Bruna; Jara, Luis M; Sato, Maria Inês Zanoli; Guerrero, Juana Arzola; Hachich, Elayse; Matté, Glavur Rogério; Dropa, Milena; Matté, Maria Helena; de Araújo, Ronalda Silva

    2016-11-01

    The objectives of the study were to detect and genotype Cryptosporidium spp. and Giardia intestinalis in wastewater samples obtained from five cities with high transit of people in the State of São Paulo, Brazil, and at the entrance of a Wastewater Treatment Plant (WWTP) in Lima, Peru. Samples were collected and concentrated by centrifugation. The genomic DNA was extracted for molecular characterization by nested PCR for Cryptosporidium and double nested PCR for Giardia, followed by sequencing and phylogenetic analysis. G. intestinalis was found in 63.6 % of the samples, and the human assemblages A and B were identified. Cryptosporidium sp. was found in 36.4 % of the samples, and the species were corresponding to Cryptosporidium hominis, Cryptosporidium cuniculus, and Cryptosporidium muris. Results revealed the presence of human pathogenic Cryptosporidium species and G. intestinalis human pathogenic assemblages. Molecular tools highlight the importance to map the genetic diversity of these parasites, as well as to detect their epidemiological circulation pathway in the environment.

  6. Immunological aspects of Giardia muris and Spironucleus muris infections in inbred and outbred strains of laboratory mice: a comparative study.

    Science.gov (United States)

    Brett, S J; Cox, F E

    1982-08-01

    The intestinal flagellates, Giardia muris and Spironucleus muris, cause similar infections in CBA mice as determined by trophozoite and cyst counts. Both parasites occur all along the small intestine with G. muris, being mainly present in the anterior part and S. muris towards the posterior. The early stages of infection are similar in all strains of mice examined and peak levels of both trophozoites and cysts occur 1-2 weeks after infection. All strains of mice overcome the infection but the rate of recovery varies considerably between strains, being most rapid in BALB/c and slowest in A and C57BL.B10. Outbred mice are more variable in their recovery than inbred mice. After recovery, mice are partially resistant to reinfection with the homologous but not the heterologous parasite. Resistance to reinfection with S. muris is greatest in those strains that eliminate the primary infection most rapidly. Giardia muris and S. muris cause similar changes in the mucosa of the small intestine of BALB/c mice with increased intra-epithelial lymphocyte counts from 3 weeks onwards corresponding with the start of the elimination of the parasites from the gut. A reduction in villus height and increase in crypt depth is also characteristic of these infections.

  7. Prevalence of intestinal parasites in companion dogs with diarrhea in Beijing, China, and genetic characteristics of Giardia and Cryptosporidium species.

    Science.gov (United States)

    Yu, Zhongjia; Ruan, Yang; Zhou, Mengjie; Chen, Siyuan; Zhang, Yinxin; Wang, Liya; Zhu, Guan; Yu, Yonglan

    2018-01-01

    Companion animals including dogs are one of the important components in One Health. Parasites may cause not only diseases in pet animals but also many zoonotic diseases infecting humans. In this study, we performed a survey of intestinal parasites in fecal specimens (n = 485) collected from outpatient pet dogs with diarrhea in Beijing, China, for the entire year of 2015 by microscopic examination (all parasites) and SSU rRNA-based nested PCR detection (Giardia and Cryptosporidium). We observed a total of 124 (25.6%) parasite-positive specimens that contained one or more parasites, including Giardia duodenalis (12.8%), Cryptosporidium spp. (4.9%), Cystoisospora spp. (4.3%), trichomonads (4.3%), Toxocara canis (3.5%), Trichuris vulpis (0.6%), and Dipylidium caninum (0.2%). Among the 55 dog breeds, infection rates were significantly higher in border collies and bulldogs, but lower in poodles (p PCR, 20 PCR amplicons could be sequenced and identified as Cryptosporidium canis (n = 20). Collectively, this study indicates that parasites are a significant group of pathogens in companion dogs in Beijing, and companion dogs may potentially transmit certain zoonotic parasites to humans, particularly those with weak or weakened immunity.

  8. The prevalence of Giardia intestinalis and Entamoeba histolytica/dispar in Van Regional Training and Research Hospital: A four-year monitoring

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    Yasemin Bayram

    2013-03-01

    Full Text Available Objective: The aim of this retrospective study was to determinethe frequency rates of Giardia and E.histolytica/E.dispar and their distribution by years as well as agegroups and gender distribution during a four-year period.Materials and methods: A total of 9911 stool samplessent to our laboratory between January 2008 and December2011 were tested for parasites. Native-Lugol and formolethyl acetate sedimentation methods were utilized formicroscopic identification of Entamoeba sp. and Giardiatrophozoites and cysts in fresh stool samples. Additionally,trichrome staining was performed in stool sampleswhere the distinctive diagnosis could not be confirmed.Results: From a total of 9911 stool samples analyzedduring the study, 4.7% were positive for Giardia and 6.2%were positive for Entemoeba histolytica/ Entemoeba dispar.Of Giardia-positive patients 57% were male and 43%female. Similarly, 56% of Entemoeba histolytica/ Entemoebadispar positive patients were male and 44% werefemale. Both parasites’ higher frequency rates seen inmale groups were found statistically significant (p<0.01.Conclusion: It is seen that intestinal protozoon infectionsare still present as an important public health problemin our region. In order to prevent this problem, personalhygiene and sanitation rules education for community aswell as infrastructure improvements are necessary.Key words: Giardia, Entemoeba histolytica/ Entemoeba dispar, prevalence

  9. Giardia survey in live-trapped small domestic and wild mammals in four regions in the southwest region of the State of São Paulo, Brazil

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    Maria Inês L. Sogayar

    1995-12-01

    Full Text Available For the first time, a survey on Giardia in the live-trapped small domestic and wild mammals was perfomed in four regions of state of the São Paulo, Brazil, with special attention to the parasitism of Rattus rattus rattus by Giardia. This species was found infected in all studied sites: Botucatu (15.4%, Conchas (28.5%, Itaporanga (38.7% and São Roque (100 %. Two new hosts and their frequency of infection were described for Giardia in Nectomys squamipes, an aquatic rodent and in Bolomys lasiurus, a forest rodent (100 % and 14.3 %, respectively. Both G. muris and G. duodenalis groups were found in scrapings of intestinal mucosa of those rodents. Mixed infection was observed in some animals. It is important to emphasize the infection by G. duodenalis in the black rat as this species lives as a comensal with man and in N. squamipes as it may contaminate small streams used for domestic consumption. Therefore, further investigation will be necessary to elucidate the potential of these rodents to act as reservoirs of Giardia for man.

  10. Comportamiento de la infección experimental por aislamientos colombianos de Giardia duodenalis en el modelo animal del gerbo (Meriones unguiculatus.

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    Adriana Arévalo

    2005-09-01

    Full Text Available Introducción. Se han informado infecciones naturales y experimentales con Giardia sp. en bovinos, equinos, caprinos, caninos, felinos y roedores como ratones, ratas y gerbos; estos últimos son el modelo más adecuado para estudios de la infección por Giardia duodenalis y Giardia muris. Objetivo. Establecer el comportamiento de la infección con aislamientos colombianos de Giardia duodenalis en el modelo animal del gerbo. Materiales y métodos. Se purificaron mediante gradientes de sacarosa y percoll quistes del parásito obtenidos a partir de heces de pacientes sintomáticos infectados. La inoculación a los animales se realizó mediante sonda gástrica con 5x103 quistes. El curso de la infección se estableció mediante recuento diario de quistes y semanal de trofozoítos durante treinta días. Resultados. La eliminación de quistes presentó un patrón intermitente de excreción, con ausencia en la primera y cuarta semanas de infección, y presencia constante durante la segunda y tercera semanas, en número variable con promedio mínimo de 79 y máximo de 17.943 quistes liberados en heces recolectadas en un período de dos horas. Se observó colonización de los trofozoítos en el intestino delgado, en número que osciló entre 15.000 y 6'577.778 trofozoítos por ml. Conclusiones. En gerbos infectados con aislamientos de Giardia duodenalis circulantes en otras regiones geográficas, la resolución natural de la infección oscila entre 86 y 114 días mientras que los gerbos infectados con aislamientos colombianos del parásito la resuelven al día 30. El gerbo constituye un modelo animal adecuado para la infección con aislamientos colombianos de G. duodenalis. La infección experimental por Giardia en gerbo permite obtener quistes y trofozoítos del parásito en cantidades suficientes con la finalidad de ser utilizados como antígenos para la inmunización de animales y para la obtención de anticuerpos que puedan utilizarse para la detecci

  11. A novel high-resolution multilocus sequence typing of Giardia intestinalis Assemblage A isolates reveals zoonotic transmission, clonal outbreaks and recombination.

    Science.gov (United States)

    Ankarklev, Johan; Lebbad, Marianne; Einarsson, Elin; Franzén, Oscar; Ahola, Harri; Troell, Karin; Svärd, Staffan G

    2018-06-01

    Molecular epidemiology and genotyping studies of the parasitic protozoan Giardia intestinalis have proven difficult due to multiple factors, such as low discriminatory power in the commonly used genotyping loci, which has hampered molecular analyses of outbreak sources, zoonotic transmission and virulence types. Here we have focused on assemblage A Giardia and developed a high-resolution assemblage-specific multilocus sequence typing (MLST) method. Analyses of sequenced G. intestinalis assemblage A genomes from different sub-assemblages identified a set of six genetic loci with high genetic variability. DNA samples from both humans (n = 44) and animals (n = 18) that harbored Giardia assemblage A infections, were PCR amplified (557-700 bp products) and sequenced at the six novel genetic loci. Bioinformatic analyses showed five to ten-fold higher levels of polymorphic sites than what was previously found among assemblage A samples using the classic genotyping loci. Phylogenetically, a division of two major clusters in assemblage A became apparent, separating samples of human and animal origin. A subset of human samples (n = 9) from a documented Giardia outbreak in a Swedish day-care center, showed full complementarity at nine genetic loci (the six new and the standard BG, TPI and GDH loci), strongly suggesting one source of infection. Furthermore, three samples of human origin displayed MLST profiles that were phylogenetically more closely related to MLST profiles from animal derived samples, suggesting zoonotic transmission. These new genotyping loci enabled us to detect events of recombination between different assemblage A isolates but also between assemblage A and E isolates. In summary, we present a novel and expanded MLST strategy with significantly improved sensitivity for molecular analyses of virulence types, zoonotic potential and source tracking for assemblage A Giardia. Copyright © 2018. Published by Elsevier B.V.

  12. Molecular epidemiology of Cryptosporidium spp. and Giardia spp. in mussels (Mytilus californianus) and California sea lions (Zalophus californianus) from Central California.

    Science.gov (United States)

    Adell, A D; Smith, W A; Shapiro, K; Melli, A; Conrad, P A

    2014-12-01

    Cryptosporidium and Giardia are of public health importance, with recognized transmission through recreational waters. Therefore, both can contaminate marine waters and shellfish, with potential to infect marine mammals in nearshore ecosystems. A 2-year study was conducted to evaluate the presence of Cryptosporidium and Giardia in mussels located at two distinct coastal areas in California, namely, (i) land runoff plume sites and (ii) locations near sea lion haul-out sites, as well as in feces of California sea lions (CSL) (Zalophus californianus) by the use of direct fluorescent antibody (DFA) detection methods and PCR with sequence analysis. In this study, 961 individual mussel hemolymph samples, 54 aliquots of pooled mussel tissue, and 303 CSL fecal samples were screened. Giardia duodenalis assemblages B and D were detected in hemolymph from mussels collected near two land runoff plume sites (Santa Rosa Creek and Carmel River), and assemblages C and D were detected in hemolymph from mussels collected near a sea lion haul-out site (White Rock). These results suggest that mussels are being contaminated by protozoa carried in terrestrial runoff and/or shed in the feces of CSL. Furthermore, low numbers of oocysts and cysts morphologically similar to Cryptosporidium and Giardia, respectively, were detected in CSL fecal samples, suggesting that CSL could be a source and a host of protozoan parasites in coastal environments. The results of this study showed that Cryptosporidium and Giardia spp. from the feces of terrestrial animals and CSL can contaminate mussels and coastal environments. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  13. Genotypes of Cryptosporidium spp., Enterocytozoon bieneusi and Giardia duodenalis in dogs and cats in Shanghai, China.

    Science.gov (United States)

    Xu, Hailing; Jin, Yue; Wu, Wenxian; Li, Pei; Wang, Lin; Li, Na; Feng, Yaoyu; Xiao, Lihua

    2016-03-01

    Controversies exist on the potential role of companion animals in the transmission of enteric pathogens in humans. This study was conducted to examine the genotype distribution of Cryptosporidium spp., Enterocytozoon bieneusi, and Giardia duodenalis in companion animals in Shanghai, China, and to assess their zoonotic potential. Fecal specimens from 485 dogs and 160 cats were examined for the occurrence and genotype distribution of the three pathogens by PCR. PCR products were sequenced to determine the species and genotypes. The χ(2) test was used to compare differences in infection rates between living conditions or age groups. Cryptosporidium spp., E. bieneusi and G. duodenalis were found in 39 (8.0 %), 29 (6.0 %) and 127 (26.2 %) of dogs, and 6 (3.8 %), 9 (5.6 %) and 21 (13.1 %) of cats, respectively. Infection rates of the pathogens in dogs from pet shops and a clinic were higher than those in household dogs, and higher in cats from one animal shelter than from pet shops. No significant differences in infection rates were detected among age groups. Cryptosporidium canis and C. felis were the only Cryptosporidium species found in dogs and cats, respectively. Enterocytozoon bieneusi genotype PtEb IX was the dominant genotype in dogs, whereas Type IV and D were the most common ones in cats. Multi-locus sequence typing at the glutamate dehydrogenase, β-giardin, and triosephosphate isomerase loci revealed the presence of G. duodenalis assemblages A (n = 23), B (n = 1), C (n = 26), and D (n = 58) in dogs (only A in household dogs) and assemblages A (n = 2), B (n = 6), C (n = 2), D (n = 1), and F (n = 7) in cats. Co-infection was detected in 24 dogs and 5 cats, especially those living in crowded conditions. Living condition is a major risk factor affecting the occurrence of enteric protists in companion animals in China, and although dogs and cats can be potential sources of human infections, the different distribution of

  14. Modeling Cryptosporidium spp. Oocyst Inactivation in Bubble-Diffuser Ozone Contactors

    Science.gov (United States)

    1998-07-01

    requirements for Giardia lamblia (G. lamblia) and viruses under the Surface Water Treatment Rule (SWTR). Minimum CT requirements include relatively...parvum and C. muris ) oocysts in ozone bubble-diffuser contactors. The model is calibrated with semi-batch kinetic data, verified with pilot-scale

  15. A comparison of mucosal inflammatory responses to Giardia muris in resistant B10 and susceptible BALB/c mice.

    Science.gov (United States)

    Venkatesan, P; Finch, R G; Wakelin, D

    1997-03-01

    In the first three weeks of primary Giardia muris infections B10 mice clear infection more rapidly than BALB/c mice. There is evidence that interferon-gamma contributes to the relative resistance of B10 mice. The nature of the functional contribution of interferon-gamma is unclear and does not relate to the secretory or serum antibody response. Mucosal inflammatory events in these strains have been studied. Apart from a small rise in both strains of goblet cell and mucosal mast cell numbers, associated with release of mast cell protease-1 in serum, no inflammatory infiltrate was observed at the time trophozoites were cleared from the intestinal lumen. Inhibition of mast cell products (5-hydroxytryptamine and histamine) by cyproheptadine enhanced the intensity of infection in both strains. The relative resistance of B10 mice could not be explained in terms of the mucosal inflammatory response.

  16. Mitochondrial-type hsp70 genes of the amitochondriate protists, Giardia intestinalis, Entamoeba histolytica and two microsporidians☆

    Science.gov (United States)

    Arisue, Nobuko; Sánchez, Lidya B.; Weiss, Louis M.; Müller, Miklós; Hashimoto, Tetsuo

    2011-01-01

    Genes encoding putative mitochondrial-type heat shock protein 70 (mit-hsp70) were isolated and sequenced from amitochondriate protists, Giardia intestinalis, Entamoeba histolytica, and two microsporidians, Encephalitozoon hellem and Glugea plecoglossi. The deduced mit-hsp70 sequences were analyzed by sequence alignments and phylogenetic reconstructions. The mit-hsp70 sequence of these four amitochondriate protists were divergent from other mit-hsp70 sequences of mitochondriate eukaryotes. However, all of these sequences were clearly located within a eukaryotic mitochondrial clade in the tree including various type hsp70 sequences, supporting the emerging notion that none of these amitochondriate lineages are primitively amitochodrial, but lost their mitochondria secondarily in their evolutionary past. PMID:11880223

  17. The effect of a fenbendazole treatment on cyst excretion and weight gain in calves experimentally infected with Giardia duodenalis.

    Science.gov (United States)

    Geurden, Thomas; Vandenhoute, Els; Pohle, Herbert; Casaert, Stijn; De Wilde, Nathalie; Vercruysse, Jozef; Claerebout, Edwin

    2010-04-19

    A total of 28 Holstein-Friesian calves were experimentally infected with 10(5)Giardia duodenalis cysts. Eleven days later, all animals were allocated into two groups of 14 animals each, based on the average pre-treatment cyst counts. Treatment was randomly assigned to one of the two groups, and all animals in the treatment group received a daily oral dosage of 15mg fenbendazole per kg bodyweight during 3 consecutive days. The calves in the control group received a placebo (water). From 3 days after treatment onwards, cyst excretion was determined three times a week during 4 consecutive weeks. The faecal consistency and general health were recorded on a daily basis, and all animals were weighed prior to treatment and weekly thereafter. At the end of the experimental period, there was a significant (Pfenbendazole treated and untreated calves experimentally infected with G. duodenalis, although additional data need to confirm the need for treatment in natural conditions.

  18. Dysfunctions at human intestinal barrier by water-borne protozoan parasites: lessons from cultured human fully differentiated colon cancer cell lines.

    Science.gov (United States)

    Liévin-Le Moal, Vanessa

    2013-06-01

    Some water-borne protozoan parasites induce diseases through their membrane-associated functional structures and virulence factors that hijack the host cellular molecules and signalling pathways leading to structural and functional lesions in the intestinal barrier. In this Microreview we analyse the insights on the mechanisms of pathogenesis of Entamoeba intestinalis, Giardia and Cryptosporidium observed in the human colon carcinoma fully differentiated colon cancer cell lines, cell subpopulations and clones expressing the structural and functional characteristics of highly specialized fully differentiated epithelial cells lining the intestinal epithelium and mimicking structurally and functionally an intestinal barrier. © 2013 John Wiley & Sons Ltd.

  19. Comparison of microscopy, ELISA, and real-time PCR for detection of Giardia intestinalis in human stool specimens

    Science.gov (United States)

    Beyhan, Yunus Emre; Taş Cengiz, Zeynep

    2017-08-23

    Background/aim: This study included patients who had digestive system complaints between August 2015 and October 2015. The research was designed to compare conventional microscopy with an antigen detection ELISA kit and the TaqMan-based real-time PCR (RT-PCR) technique for detection of Giardia intestinalis in human stool specimens. Materials and methods: Samples were concentrated by formalin-ether sedimentation technique and microscopic examinations were carried out on wet mount slides. A commercially available ELISA kit (Giardia CELISA, Cellabs, Brookvale, Australia) was used for immunoassay. DNA was extracted from fecal samples of about 200 mg using the QIAamp Fast DNA Stool Mini Kit (QIAGEN, Hilden, Germany) and the LightCycler Nano system (Roche Diagnostics, Mannheim, Germany) was used for the TaqMan-based RT-PCR assay. Results: A total of 94 stool samples, 38 of them diagnosed positive (40.4%) and 56 of them diagnosed negative by microscopy, were selected for evaluation by antigen detection and molecular assays. The prevalence of G. intestinalis infection was found as 46.8% (n: 44) and 79.8% (n: 75) by ELISA and RT-PCR, respectively. RT-PCR revealed by far the highest positivity rate compared to the other two methods. The difference between these methods was found to be statistically significant (P PCR, the sensitivity and specificity of microscopy and ELISA were 50.7% and 100% and 53.3% and 79%, respectively. Conclusion: RT-PCR seems to be much more sensitive and beneficial for rapid and accurate diagnosis of G. intestinalis in human stools.

  20. Prevalence and Risk Factors for Intestinal Protozoan Infections with Cryptosporidium, Giardia, Blastocystis and Dientamoeba among Schoolchildren in Tripoli, Lebanon.

    Science.gov (United States)

    Osman, Marwan; El Safadi, Dima; Cian, Amandine; Benamrouz, Sadia; Nourrisson, Céline; Poirier, Philippe; Pereira, Bruno; Razakandrainibe, Romy; Pinon, Anthony; Lambert, Céline; Wawrzyniak, Ivan; Dabboussi, Fouad; Delbac, Frederic; Favennec, Loïc; Hamze, Monzer; Viscogliosi, Eric; Certad, Gabriela

    2016-03-01

    Intestinal protozoan infections are confirmed as major causes of diarrhea, particularly in children, and represent a significant, but often neglected, threat to public health. No recent data were available in Lebanon concerning the molecular epidemiology of protozoan infections in children, a vulnerable population at high risk of infection. In order to improve our understanding of the epidemiology of intestinal pathogenic protozoa, a cross-sectional study was conducted in a general pediatric population including both symptomatic and asymptomatic subjects. After obtaining informed consent from the parents or legal guardians, stool samples were collected in January 2013 from 249 children in 2 schools in Tripoli, Lebanon. Information obtained from a standard questionnaire included demographic characteristics, current symptoms, socioeconomic status, source of drinking water, and personal hygiene habits. After fecal examination by both microscopy and molecular tools, the overall prevalence of parasitic infections was recorded as 85%. Blastocystis spp. presented the highest infection rate (63%), followed by Dientamoeba fragilis (60.6%), Giardia duodenalis (28.5%) and Cryptosporidium spp. (10.4%). PCR was also performed to identify species and genotypes of Cryptosporidium, subtypes of Blastocystis, and assemblages of Giardia. Statistical analysis using a logistic regression model showed that contact with family members presenting gastrointestinal disorders was the primary risk factor for transmission of these protozoa. This is the first study performed in Lebanon reporting the prevalence and the clinical and molecular epidemiological data associated with intestinal protozoan infections among schoolchildren in Tripoli. A high prevalence of protozoan parasites was found, with Blastocystis spp. being the most predominant protozoans. Although only 50% of children reported digestive symptoms, asymptomatic infection was observed, and these children may act as unidentified

  1. Constraint Differentiation

    DEFF Research Database (Denmark)

    Mödersheim, Sebastian Alexander; Basin, David; Viganò, Luca

    2010-01-01

    We introduce constraint differentiation, a powerful technique for reducing search when model-checking security protocols using constraint-based methods. Constraint differentiation works by eliminating certain kinds of redundancies that arise in the search space when using constraints to represent...... results show that constraint differentiation substantially reduces search and considerably improves the performance of OFMC, enabling its application to a wider class of problems....

  2. Differential manifolds

    CERN Document Server

    Kosinski, Antoni A

    2007-01-01

    The concepts of differential topology form the center of many mathematical disciplines such as differential geometry and Lie group theory. Differential Manifolds presents to advanced undergraduates and graduate students the systematic study of the topological structure of smooth manifolds. Author Antoni A. Kosinski, Professor Emeritus of Mathematics at Rutgers University, offers an accessible approach to both the h-cobordism theorem and the classification of differential structures on spheres.""How useful it is,"" noted the Bulletin of the American Mathematical Society, ""to have a single, sho

  3. Cryptosporidium and Giardia in Danish organic pig farms: seasonal and age-related variation in prevalence, infection intensity and species/genotypes

    DEFF Research Database (Denmark)

    Petersen, Heidi Huus; Jianmin, Wang; Katakam, Kiran K.

    2015-01-01

    Although pigs are commonly infected with Cryptosporidium spp. and Giardia duodenalis, including potentially zoonotic species or genotypes, little is known about age-related infection levels, seasonal differences and genetic variation in naturally infected pigs raised in organic management systems....... Therefore, the current study was conducted to assess seasonal and age-related variations in prevalence and infection intensity of Cryptosporidium and Giardia, evaluate zoonotic potential and uncover correlations between species/genotypes, infection intensity and faecal consistency. Shedding of oocysts...... and cysts ((oo-) cysts) was monitored at quarterly intervals (September 2011 to June 2012) in piglets (n=152), starter pigs (n=234), fatteners (n=230) and sows (n=240) from three organic farms in Denmark. (Oo-) cysts were quantified by immunofluorescence microscopy; and 56/75 subsamples from Cryptosporidium...

  4. Differential equations

    CERN Document Server

    Barbu, Viorel

    2016-01-01

    This textbook is a comprehensive treatment of ordinary differential equations, concisely presenting basic and essential results in a rigorous manner. Including various examples from physics, mechanics, natural sciences, engineering and automatic theory, Differential Equations is a bridge between the abstract theory of differential equations and applied systems theory. Particular attention is given to the existence and uniqueness of the Cauchy problem, linear differential systems, stability theory and applications to first-order partial differential equations. Upper undergraduate students and researchers in applied mathematics and systems theory with a background in advanced calculus will find this book particularly useful. Supplementary topics are covered in an appendix enabling the book to be completely self-contained.

  5. Prevalence of Giardia and Cryptosporidium species in dog park attending dogs compared to non-dog park attending dogs in one region of Colorado.

    Science.gov (United States)

    Wang, Andrea; Ruch-Gallie, Rebecca; Scorza, Valeria; Lin, Philip; Lappin, Michael R

    2012-03-23

    Dog parks are very popular in urban areas, but there are no current studies attempting to correlate visits to dog parks and risk of colonization by enteric parasites. The purpose of this study was to determine whether dog park visitation is associated with an increased prevalence of enteric parasites or an increase in prevalence of gastrointestinal signs in dogs in northern Colorado. Feces from dogs owned by veterinary students or Veterinary Teaching Hospital staff members were submitted with a completed survey form detailing dog park attendance rates, fecal character scores, and other clinical information. Feces were examined microscopically for parasites after sugar centrifugation, for Giardia spp. cysts and Cryptosporidium spp. oocysts by a commercially available immunofluorescence assay (FA) and the FA positive samples were genotyped after PCR amplification. The Giardia assemblages were determined using the glutamate dehydrogenase (GDH) β-giardin and triose phosphate isomerase (TPI) genes and the Cryptosporidium species were determined using the heat shock protein-70 gene. A total of 129 fecal samples were assayed; 66 were from dog park attending dogs and 63 were from non-dog park-attending dogs. The overall parasite prevalence rate was 7.0% (9 of 129 samples). Dog park attending dogs were more likely to be positive for Giardia or Cryptosporidium than non-dog park-attending dogs (p=0.0279), but there was no association of gastrointestinal signs with dog park attendance or with fecal flotation or FA results. The five Giardia isolates were assemblage C and/or D and the one Cryptosporidium isolate was Ctenocephalides canis. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. Occurrence of Cryptosporidium and Giardia in recycled waters used for irrigation and first description of Cryptosporidium parvum and C. muris in Greece.

    Science.gov (United States)

    Spanakos, Gregory; Biba, Anastasia; Mavridou, Athena; Karanis, Panagiotis

    2015-05-01

    Here, we present the first time findings regarding the occurrence of Cryptosporidium and Giardia in sewage waters and the first molecular characterization of Cryptosporidium species in Greece. Biological treatment plants from three regions in Greece have been investigated. The detection of Cryptosporidium oocysts was by modified Ziehl-Neelsen acid fast (MZN-AF) and by immunofluorescence microscopy (IFT) for Cryptosporidium and Giardia (oo)cysts, whereas nested PCR based on the SSU rDNA assay was used for molecular detection of Cryptosporidium followed by sequencing for the genetic characterization of the species. In total, 73 samples (37 raw sewage samples and 38 of treated water samples) were collected and analyzed. Of the 73 water samples, 4 samples were Cryptosporidium-positive by IFT and staining, 12 samples were Cryptosporidium-positive by nested PCR; 9 samples were Giardia-positive by IFT. We showed that Cryptosporidium cysts are found both in the input and the discharge of the biological treatment plants. Molecular characterization of Cryptosporidium based on the small subunit ribosomal DNA gene resulted in the determination of Cryptosporidium parvum and Cryptosporidium muris Greek isolates. This is the first report of Cryptosporidium and Giardia occurrence in wastewaters and the first molecular identification of Cryptosporidium species in Greek environments. As the treated water is used for irrigation, or it is discharged into the sea, our findings indicate that biological treatment facilities constitute a possible risk for public health because the related species are prevalent in humans; the results invite for further epidemiological investigations to evaluate the real public health risk in Greece.

  7. Assessing viability and infectivity of foodborne and waterborne stages (cysts/oocysts of Giardia duodenalis, Cryptosporidium spp., and Toxoplasma gondii: a review of methods

    Directory of Open Access Journals (Sweden)

    Rousseau Angélique

    2018-01-01

    Full Text Available Giardia duodenalis, Cryptosporidium spp. and Toxoplasma gondii are protozoan parasites that have been highlighted as emerging foodborne pathogens by the Food and Agriculture Organization of the United Nations and the World Health Organization. According to the European Food Safety Authority, 4786 foodborne and waterborne outbreaks were reported in Europe in 2016, of which 0.4% were attributed to parasites including Cryptosporidium, Giardia and Trichinella. Until 2016, no standardized methods were available to detect Giardia, Cryptosporidium and Toxoplasma (oocysts in food. Therefore, no regulation exists regarding these biohazards. Nevertheless, considering their low infective dose, ingestion of foodstuffs contaminated by low quantities of these three parasites can lead to human infection. To evaluate the risk of protozoan parasites in food, efforts must be made towards exposure assessment to estimate the contamination along the food chain, from raw products to consumers. This requires determining: (i the occurrence of infective protozoan (oocysts in foods, and (ii the efficacy of control measures to eliminate this contamination. In order to conduct such assessments, methods for identification of viable (i.e. live and infective parasites are required. This review describes the methods currently available to evaluate infectivity and viability of G. duodenalis cysts, Cryptosporidium spp. and T. gondii oocysts, and their potential for application in exposure assessment to determine the presence of the infective protozoa and/or to characterize the efficacy of control measures. Advantages and limits of each method are highlighted and an analytical strategy is proposed to assess exposure to these protozoa.

  8. Seroprevalences of antibodies against Bartonella henselae and Toxoplasma gondii and fecal shedding of Cryptosporidium spp, Giardia spp, and Toxocara cati in feral and pet domestic cats.

    Science.gov (United States)

    Nutter, Felicia B; Dubey, J P; Levine, Jay F; Breitschwerdt, Edward B; Ford, Richard B; Stoskopf, Michael K

    2004-11-01

    To compare seroprevalences of antibodies against Bartonella henselae and Toxoplasma gondii and fecal shedding of Cryptosporidium spp, Giardia spp, and Toxocara cati in feral and pet domestic cats. Prospective cross-sectional serologic and coprologic survey. 100 feral cats and 76 pet domestic cats from Randolph County, NC. Blood and fecal samples were collected and tested. Percentages of feral cats seropositive for antibodies against B. henselae and T. gondii (93% and 63%, respectively) were significantly higher than percentages of pet cats (75% and 34%). Percentages of feral and pet cats with Cryptosporidium spp (7% of feral cats; 6% of pet cats), Giardia spp (6% of feral cats; 5% of pet cats), and T. cati ova (21% of feral cats; 18% of pet cats) in their feces were not significantly different between populations. Results of CBCs and serum biochemical analyses were not significantly different between feral and pet cats, except that feral cats had a significantly lower median PCV and significantly higher median neutrophil count. Results suggested that feral and pet cats had similar baseline health status, as reflected by results of hematologic and serum biochemical testing and similar prevalences of infection with Cryptosporidium spp, Giardia spp, and T. cati. Feral cats did have higher seroprevalences of antibodies against B. henselae and T. gondii than did pet cats, but this likely was related to greater exposure to vectors of these organisms.

  9. First report of predation of Giardia sp. cysts by ciliated protozoa and confirmation of predation of Cryptosporidium spp. oocysts by ciliate species.

    Science.gov (United States)

    Siqueira-Castro, Isabel Cristina Vidal; Greinert-Goulart, Juliane Araújo; Bonatti, Tais Rondello; Yamashiro, Sandra; Franco, Regina Maura Bueno

    2016-06-01

    Ciliated protozoa are important components of the microbial food web in various habitats, especially aquatic environments. These organisms are useful bioindicators for both environmental quality assessment and the wastewater purification process. The pathogenic parasitic protozoan species Giardia and Cryptosporidium represent a significant concern for human health, being responsible for numerous disease outbreaks worldwide. The predation of cysts and oocysts in 15 ciliate species from water and sewage samples collected in Campinas, São Paulo, Brazil were verified under laboratory conditions. The ciliated protozoan species were selected based on their mode of nutrition, and only bacterivorous and suspension-feeders were considered for the experiments. The species Blepharisma sinuosum, Euplotes aediculatus, Sterkiella cavicola, Oxytricha granulifera, Vorticella infusionum, Spirostomum minus, and Stentor coeruleus ingested cysts and oocysts, the resistance forms of Giardia spp. and Cryptosporidium spp., respectively. This is the first time that the ingestion of Giardia cysts by ciliated protozoa has been reported. These findings may contribute to a better understanding of the biological removal of these pathogens from aquatic environments.

  10. Giardia and Cryptosporidium spp. dissemination during wastewater treatment and comparative detection via immunofluorescence assay (IFA), nested polymerase chain reaction (nested PCR) and loop mediated isothermal amplification (LAMP).

    Science.gov (United States)

    Gallas-Lindemann, Carmen; Sotiriadou, Isaia; Plutzer, Judit; Noack, Michael J; Mahmoudi, Mohammad Reza; Karanis, Panagiotis

    2016-06-01

    Environmental water samples from the Lower Rhine area in Germany were investigated via immunofluorescence assays (IFAs), nested polymerase chain reaction (nested PCR) and loop-mediated isothermal amplification (LAMP) to detect the presence of Giardia spp. (n=185) and Cryptosporidium spp. (n=227). The samples were concentrated through filtration or flocculation, and oocysts were purified via centrifugation through a sucrose density gradient. For all samples, IFA was performed first, followed by DNA extraction for the nested PCR and LAMP assays. Giardia cysts were detected in 105 samples (56.8%) by IFA, 62 samples (33.5%) by nested PCR and 79 samples (42.7%) by LAMP. Cryptosporidium spp. were detected in 69 samples (30.4%) by IFA, 95 samples (41.9%) by nested PCR and 99 samples (43.6%) by LAMP. According to these results, the three detection methods are complementary for monitoring Giardia and Cryptosporidium in environmental waters. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Differential games

    CERN Document Server

    Friedman, Avner

    2006-01-01

    This volume lays the mathematical foundations for the theory of differential games, developing a rigorous mathematical framework with existence theorems. It begins with a precise definition of a differential game and advances to considerations of games of fixed duration, games of pursuit and evasion, the computation of saddle points, games of survival, and games with restricted phase coordinates. Final chapters cover selected topics (including capturability and games with delayed information) and N-person games.Geared toward graduate students, Differential Games will be of particular interest

  12. Modulation of human dendritic cell activity by Giardia and helminth antigens

    DEFF Research Database (Denmark)

    Summan, Anneka; Nejsum, Peter; Williams, Andrew R

    2018-01-01

    by modulating cytokine secretion and/or inducing apoptosis, which may be a parasite driven mechanism to dampen host immunity and establish chronic infections. The differential mechanisms of DC modulation by intestinal parasites warrant further attention. This article is protected by copyright. All rights...

  13. Differential Geometry

    CERN Document Server

    Stoker, J J

    2011-01-01

    This classic work is now available in an unabridged paperback edition. Stoker makes this fertile branch of mathematics accessible to the nonspecialist by the use of three different notations: vector algebra and calculus, tensor calculus, and the notation devised by Cartan, which employs invariant differential forms as elements in an algebra due to Grassman, combined with an operation called exterior differentiation. Assumed are a passing acquaintance with linear algebra and the basic elements of analysis.

  14. Survey of the Occurrence and Human Infective Potential of Giardia duodenalis and Cryptosporidium spp. in Wastewater and Different Surface Water Sources of Western Romania.

    Science.gov (United States)

    Imre, Kálmán; Morar, Adriana; Ilie, Marius S; Plutzer, Judit; Imre, Mirela; Emil, Tîrziu; Herbei, Mihai V; Dărăbuș, Gheorghe

    2017-10-01

    From the group of parasitic protozoa, Giardia and Cryptosporidium are the most common pathogens spread in surface water sources, representing a continuous threat to public health and water authorities. The aim of this survey was to assess the occurrence and human infective potential of these pathogens in treated wastewaters and different surface water sources. A total of 76 western Romanian water bodies in four counties (Arad, Bihor, Caraș-Severin and Timiș) were investigated, including the effluents of wastewater treatment plants (n = 11) and brooks (n = 19), irrigation channels (n = 8), lakes (n = 16), and ponds (n = 22). Water samples were collected through polyester microfiber filtration. Giardia cysts and Cryptosporidium oocysts were isolated using immunomagnetic separation, according to the US EPA 1623 method, followed by their identification and counting by immunofluorescence (IF) microscopy. All samples were screened through PCR-based techniques targeting the gdh gene for Giardia spp. and the 18S rRNA gene for Cryptosporidium spp., followed by sequencing of the positive results. Cryptosporidium-positive samples were subtyped based on sequence analysis of the GP60 gene. Giardia spp. was found in all tested water types with a cumulative detection rate of 90.1% in wastewaters, 26.3% in brooks, 37.5% in irrigation channels, 31.2% in lakes, and 36.4% in ponds. Except for ponds, all monitored water bodies harbored the Giardia duodenalis AII subassemblage with human infective potential. In addition, the ruminant origin assemblage E was widely distributed, and the domestic/wild canid-specific assemblage D was also recorded in a pond. Three (27.3%) wastewater samples were Cryptosporidium positive, and the identified species was the zoonotic Cryptosporidium parvum, with IIaA15G2R1 (n = 2) and IIdA18G1 subtypes. The results highlight that this threat to the public health must be brought to the attention of epidemiologists, health officials

  15. Detection of Giardia intestinalis in water samples collected from natural water reservoirs and wells in northern and north-eastern Poland using LAMP, real-time PCR and nested PCR.

    Science.gov (United States)

    Lass, Anna; Szostakowska, Beata; Korzeniewski, Krzysztof; Karanis, Panagiotis

    2017-10-01

    Giardia intestinalis is a protozoan parasite, transmitted to humans and animals by the faecal-oral route, mainly through contaminated water and food. Knowledge about the distribution of this parasite in surface water in Poland is fragmentary and incomplete. Accordingly, 36 environmental water samples taken from surface water reservoirs and wells were collected in Pomerania and Warmia-Masuria provinces, Poland. The 50 L samples were filtered and subsequently analysed with three molecular detection methods: loop-mediated isothermal amplification (LAMP), real-time polymerase chain reaction (real-time PCR) and nested PCR. Of the samples examined, Giardia DNA was found in 15 (42%) samples with the use of LAMP; in 12 (33%) of these samples, Giardia DNA from this parasite was also detected using real-time PCR; and in 9 (25%) using nested PCR. Sequencing of selected positive samples confirmed that the PCR products were fragments of the Giardia intestinalis small subunit rRNA gene. Genotyping using multiplex real-time PCR indicated the presence of assemblages A and B, with the latter predominating. The results indicate that surface water in Poland, as well as water taken from surface wells, may be a source of Giardia strains which are potentially pathogenic for humans. It was also demonstrated that LAMP assay is more sensitive than the other two molecular assays.

  16. [Genetic profiling of Giardia intestinalis by polimerase chain in human and dogs samples of Colombian Caribean Coast].

    Science.gov (United States)

    Arroyo-Salgado, Bárbara; Buelvas-Montes, Yaleyvis; Villalba-Vizcaíno, Vivian; Salomón-Arzuza, Octavio

    2014-01-01

    Giardia intestinalis (G. Intestinalis) is a protozoan that causes diarrheal disease and malabsorption syndrome in humans and other mammals. It presents a high genetic diversity evidenced in the recognition of 7 genotypes (A-G). Genotypes A and B are commonly associated to humans and domestic animals such as dogs. The aim of this study was to conduct a preliminary genetic characterization of G. intestinalis in humans and dogs from two cities on the Caribbean coast of Colombia. Sampling areas were selected according to the highest numbers of acute diarrheal disease. Stool samples were collected from children under 7 years old, with positive medical tests for G. intestinalis. Cysts were purified by sucrose gradient and DNA samples were isolated by extraction with organic solvents. Molecular characterization was performed by amplifying the gene triose phosphate isomerase (tpi) by using a semi-nested PCR. A total of 202 samples of DNA were obtained; of these, 111 were positive in coproparasitological analysis (13 dogs and 98 children). Genotype distribution in positive samples was: 5.1% belonged to genotype A and 92.3% to genotype B. Genotype B was present in humans and animals. The most common genotype in both human and animal samples was genotype B, suggesting a zoonotic transmission cycle. Copyright © 2012 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

  17. Flow-through immunomagnetic separation system for waterborne pathogen isolation and detection: Application to Giardia and Cryptosporidium cell isolation

    Energy Technology Data Exchange (ETDEWEB)

    Ramadan, Qasem, E-mail: qasem.alramadan@epfl.ch [Bioelectronics Program, Institute of Microelectronics, 11 Science Park Road, Singapore 117685 (Singapore); Christophe, Lay; Teo, William; ShuJun, Li; Hua, Feng Han [Bioelectronics Program, Institute of Microelectronics, 11 Science Park Road, Singapore 117685 (Singapore)

    2010-07-12

    Simultaneous sample washing and concentration of two waterborne pathogen samples were demonstrated using a rotational magnetic system under continuous flow conditions. The rotation of periodically arranged small permanent magnets close to a fluidic channel carrying magnetic particle suspension allows the trapping and release of particles along the fluidic channel in a periodic manner. Each trapping and release event resembles one washing cycle. The performance of the magnetic separation system (MSS) was evaluated in order to test its functionality to isolate magnetic-labelled protozoan cells from filtered, concentrated tap water, secondary effluent water, and purified water. Experimental protocols described in US Environmental Protection Agency method 1623 which rely on the use of a magnetic particle concentrator, were applied to test and compare our continuous flow cell separation system to the standard magnetic bead-based isolation instruments. The recovery efficiencies for Giardia cysts using the magnetic tube holder and our magnetic separation system were 90.5% and 90.1%, respectively, from a tap water matrix and about 31% and 18.5%, respectively, from a spiked secondary effluent matrix. The recovery efficiencies for Cryptosporidium cells using the magnetic tube holder and our magnetic separation system were 90% and 83.3%, respectively, from a tap water matrix and about 38% and 36%, respectively, from a spiked secondary effluent matrix. Recoveries from all matrices with the continuous flow system were typically higher in glass tubing conduits than in molded plastic conduits.

  18. Multilocus genotyping of Giardia duodenalis in captive non-human primates in Sichuan and Guizhou provinces, Southwestern China.

    Directory of Open Access Journals (Sweden)

    Zhijun Zhong

    Full Text Available Giardia duodenalis is a common human and animal pathogen. It has been increasingly reported in wild and captive non-human primates (NHPs in recent years. However, multilocus genotyping information for G. duodenalis infecting NHPs in southwestern China is limited. In the present study, the prevalence and multilocus genotypes (MLGs of G. duodenalis in captive NHPs in southwestern China were determined. We examined 207 fecal samples from NHPs in Sichuan and Guizhou provinces, and 16 specimens were positive for G. duodenalis. The overall infection rate was 7.7%, and only assemblage B was identified. G. duodenalis was detect positive in northern white-cheeked gibbon (14/36, 38.9%, crab-eating macaque (1/60, 1.7% and rhesus macaques (1/101, 0.9%. Multilocus sequence typing based on beta-giardin (bg, triose phosphate isomerase (tpi and glutamate dehydrogenase (gdh revealed nine different assemblage B MLGs (five known genotypes and four novel genotypes. Based on a phylogenetic analysis, one potentially zoonotic genotype of MLG SW7 was identified in a northern white-cheeked gibbon. A high degree of genetic diversity within assemblage B was observed in captive northern white-cheeked gibbons in Southwestern China, including a potentially zoonotic genotype, MLG SW7. To the best of our knowledge, this is the first report using a MLGs approach to identify G. duodenalis in captive NHPs in Southwestern China.

  19. Diversity of microsporidia, Cryptosporidium and Giardia in mountain gorillas (Gorilla beringei beringei in Volcanoes National Park, Rwanda.

    Directory of Open Access Journals (Sweden)

    Bohumil Sak

    Full Text Available Infectious diseases represent the greatest threats to endangered species, and transmission from humans to wildlife under increased anthropogenic pressure has been always stated as a major risk of habituation.To evaluate the impact of close contact with humans on the occurrence of potentially zoonotic protists in great apes, one hundred mountain gorillas (Gorilla beringei beringei from seven groups habituated either for tourism or for research in Volcanoes National Park, Rwanda were screened for the presence of microsporidia, Cryptosporidium spp. and Giardia spp. using molecular diagnostics.The most frequently detected parasites were Enterocytozoon bieneusi found in 18 samples (including genotype EbpA, D, C, gorilla 2 and five novel genotypes gorilla 4-8 and Encephalitozoon cuniculi with genotype II being more prevalent (10 cases compared to genotype I (1 case. Cryptosporidium muris (2 cases and C. meleagridis (2 cases were documented in great apes for the first time. Cryptosporidium sp. infections were identified only in research groups and occurrence of E. cuniculi in research groups was significantly higher in comparison to tourist groups. No difference in prevalence of E. bieneusi was observed between research and tourist groups.Although our data showed the presence and diversity of important opportunistic protists in Volcanoes gorillas, the source and the routes of the circulation remain unknown. Repeated individual sampling, broad sampling of other hosts sharing the habitat with gorillas and quantification of studied protists would be necessary to acquire more complex data.

  20. Diversity of microsporidia, Cryptosporidium and Giardia in mountain gorillas (Gorilla beringei beringei) in Volcanoes National Park, Rwanda.

    Science.gov (United States)

    Sak, Bohumil; Petrželková, Klára J; Květoňová, Dana; Mynářová, Anna; Pomajbíková, Kateřina; Modrý, David; Cranfield, Michael R; Mudakikwa, Antoine; Kváč, Martin

    2014-01-01

    Infectious diseases represent the greatest threats to endangered species, and transmission from humans to wildlife under increased anthropogenic pressure has been always stated as a major risk of habituation. To evaluate the impact of close contact with humans on the occurrence of potentially zoonotic protists in great apes, one hundred mountain gorillas (Gorilla beringei beringei) from seven groups habituated either for tourism or for research in Volcanoes National Park, Rwanda were screened for the presence of microsporidia, Cryptosporidium spp. and Giardia spp. using molecular diagnostics. The most frequently detected parasites were Enterocytozoon bieneusi found in 18 samples (including genotype EbpA, D, C, gorilla 2 and five novel genotypes gorilla 4-8) and Encephalitozoon cuniculi with genotype II being more prevalent (10 cases) compared to genotype I (1 case). Cryptosporidium muris (2 cases) and C. meleagridis (2 cases) were documented in great apes for the first time. Cryptosporidium sp. infections were identified only in research groups and occurrence of E. cuniculi in research groups was significantly higher in comparison to tourist groups. No difference in prevalence of E. bieneusi was observed between research and tourist groups. Although our data showed the presence and diversity of important opportunistic protists in Volcanoes gorillas, the source and the routes of the circulation remain unknown. Repeated individual sampling, broad sampling of other hosts sharing the habitat with gorillas and quantification of studied protists would be necessary to acquire more complex data.

  1. Diversity of Microsporidia, Cryptosporidium and Giardia in Mountain Gorillas (Gorilla beringei beringei) in Volcanoes National Park, Rwanda

    Science.gov (United States)

    Sak, Bohumil; Petrželková, Klára J.; Květoňová, Dana; Mynářová, Anna; Pomajbíková, Kateřina; Modrý, David; Cranfield, Michael R.; Mudakikwa, Antoine; Kváč, Martin

    2014-01-01

    Background Infectious diseases represent the greatest threats to endangered species, and transmission from humans to wildlife under increased anthropogenic pressure has been always stated as a major risk of habituation. Aims To evaluate the impact of close contact with humans on the occurrence of potentially zoonotic protists in great apes, one hundred mountain gorillas (Gorilla beringei beringei) from seven groups habituated either for tourism or for research in Volcanoes National Park, Rwanda were screened for the presence of microsporidia, Cryptosporidium spp. and Giardia spp. using molecular diagnostics. Results The most frequently detected parasites were Enterocytozoon bieneusi found in 18 samples (including genotype EbpA, D, C, gorilla 2 and five novel genotypes gorilla 4–8) and Encephalitozoon cuniculi with genotype II being more prevalent (10 cases) compared to genotype I (1 case). Cryptosporidium muris (2 cases) and C. meleagridis (2 cases) were documented in great apes for the first time. Cryptosporidium sp. infections were identified only in research groups and occurrence of E. cuniculi in research groups was significantly higher in comparison to tourist groups. No difference in prevalence of E. bieneusi was observed between research and tourist groups. Conclusion Although our data showed the presence and diversity of important opportunistic protists in Volcanoes gorillas, the source and the routes of the circulation remain unknown. Repeated individual sampling, broad sampling of other hosts sharing the habitat with gorillas and quantification of studied protists would be necessary to acquire more complex data. PMID:25386754

  2. Coagulation, flocculation, dissolved air flotation and filtration in the removal of Giardia spp. and Cryptosporidium spp. from water supply.

    Science.gov (United States)

    Andreoli, Fernando César; Sabogal-Paz, Lyda Patricia

    2017-11-15

    Removing protozoa from a water supply using coagulation, flocculation, dissolved air flotation (DAF) and filtration on a bench scale was evaluated. Calcium carbonate flocculation with and without immunomagnetic separation (IMS) was chosen to detect Giardia spp. cysts and Cryptosporidium spp. oocysts in the studied samples. The results indicated that DAF removed between 1.31 log and 1.79 log of cysts and between 1.08 log and 1.42 log of oocysts. The performance was lower in filtration, with the removal of 1.07 log-1.44 log for cysts and 0.82 log-0.98 log for oocysts. The coagulation, flocculation, DAF and filtration steps removed more than 2.2 log of cysts and oocysts from the water studied. However, protozoa were detected in the filtered water, even with turbidity values of 0.2 NTU. The recovery of the detection method met the international criteria and was higher when there was no IMS. Including the third acid dissociation in the IMS was critical to improve the performance of the protocol tested. However, there was an increase in the technical and analytical complexity and costs. It was also observed that the efficiency of the treatment was linked to the performance of the selected method of detecting protozoa.

  3. Goats in the city: prevalence of Giardia duodenalis and Cryptosporidium spp. in extensively reared goats in northern India.

    Science.gov (United States)

    Utaaker, Kjersti Selstad; Myhr, Nina; Bajwa, Rajinder Singh; Joshi, Himanshu; Kumar, Anil; Robertson, Lucy J

    2017-12-22

    Various characteristics of goats mean they are highly suitable livestock for backyard rearing by people with limited resources. They are a popular livestock choice in India, where they are often kept to supplement an already scarce income. In these settings, hygiene and sanitation standards tend to be low, and weakens the interface between humans and animals, thus reducing the barrier between them and thereby increasing the likelihood that zoonotic and anthroponotic infections will occur. This study reports an investigation of the occurrence of Cryptosporidium spp. and Giardia duodenalis in goats being reared in different settings in urban and peri-urban areas in northern India, and addressed the zoonotic potential of these important protozoan parasites shed from goats living close to humans. The overall prevalence of G. duodenalis was 33.8 and 0.5% for Cryptosporidium spp.; the relatively low prevalence of cryptosporidiosis may reflect that most samples were derived from adult animals. The prevalence of G. duodenalis excretion was found to be similar to that reported in other studies. However, although other studies have reported a predominance of non-zoonotic Assemblage E in goats, in this study potentially zoonotic Assemblages predominated [Assemblage A (36%) and Assemblage B (32%)]. The results of this study indicate that in this area where goats and humans are living in close proximity, there may be sharing of intestinal parasites, which can be detrimental for both host species.

  4. Giardia intestinalis and other zoonotic parasites: prevalence in adult dogs from the southern part of Mexico City.

    Science.gov (United States)

    Ponce-Macotela, Martha; Peralta-Abarca, Gustavo E; Martínez-Gordillo, Mario N

    2005-07-15

    The protozoan Giardia intestinalis is a mammalian-infecting parasite. It produces diarrhoea and malabsorption in its hosts. There is growing evidence that dogs could be reservoirs and play an important role in transmission. In Mexico, there are few data on the frequency of G. intestinalis. Therefore, we studied the small intestine of stray dogs, euthanazed at the "Culhuacan" Control Canine Centre, towards the end of 1997 and during the summer of 1998. We microscopically analysed intestinal contents and mucus samples taken every 3cm. During the cold season (winter), parasites were not found in 38/100 dogs, in contrast to 8/100 through the warm season. We found that 42/100 in winter and 51/100 in summer harboured G. intestinalis. To our knowledge, these G. intestinalis frequencies are the highest found in adult dogs worldwide. The results showed a rise in Ancylostoma spp. from 23/100 to 67/100 during the cold and warm seasons. Toxocara canis frequencies varied between 12/100 and 18/100, respectively. The data suggest that the probability of infection is higher during the hottest months compared to the coldest months of the year. Both puppies and adult dogs are highly infected. Dogs are reservoirs for zoonotic parasites; for this reason, it is imperative for humans to avoid fecal contamination in streets, public gardens and parks.

  5. Occurrence of Giardia, Cryptosporidium, and Entamoeba in wild rhesus macaques (Macaca mulatta living in urban and semi-rural North-West India

    Directory of Open Access Journals (Sweden)

    John J. Debenham

    2017-04-01

    Full Text Available Giardia duodenalis, Cryptosporidium spp., and Entamoeba spp. are intestinal protozoa capable of infecting a range of host species, and are important causes of human morbidity and mortality. Understanding their epidemiology is important, both for public health and for the health of the animals they infect. This study investigated the occurrence of these protozoans in rhesus macaques (Macaca mulatta in India, with the aim of providing preliminary information on the potential for transmission of these pathogens between macaques and humans. Faecal samples (n = 170 were collected from rhesus macaques from four districts of North-West India. Samples were analysed for Giardia/Cryptosporidium using a commercially available direct immunofluorescent antibody test after purification via immunomagnetic separation. Positive samples were characterised by sequencing of PCR products. Occurrence of Entamoeba was investigated first by using a genus-specific PCR, and positive samples further investigated via species-specific PCRs for Entamoeba coli, Entamoeba histolytica, Entamoeba dispar and Entamoeba moshkovskii. Giardia cysts were found in 31% of macaque samples, with all isolates belonging to Assemblage B. Cryptosporidium oocysts were found in 1 sample, however this sample did not result in amplification by PCR. Entamoeba spp. were found in 79% of samples, 49% of which were positive for E. coli. Multiplex PCR for E. histolytica, E. dispar and E. moshkovskii, did not result in amplification in any of the samples. Thus in 51% of the samples positive at the genus specific PCR, the Entamoeba species was not identified. This study provides baseline information on the potential for transmission of these zoonotic parasites at the wildlife-human interface.

  6. Differential discriminator

    International Nuclear Information System (INIS)

    Dukhanov, V.I.; Mazurov, I.B.

    1981-01-01

    A principal flowsheet of a differential discriminator intended for operation in a spectrometric circuit with statistical time distribution of pulses is described. The differential discriminator includes four integrated discriminators and a channel of piled-up signal rejection. The presence of the rejection channel enables the discriminator to operate effectively at loads of 14x10 3 pulse/s. The temperature instability of the discrimination thresholds equals 250 μV/ 0 C. The discrimination level changes within 0.1-5 V, the level shift constitutes 0.5% for the filling ratio of 1:10. The rejection coefficient is not less than 90%. Alpha spectrum of the 228 Th source is presented to evaluate the discriminator operation with the rejector. The rejector provides 50 ns time resolution

  7. Differential topology

    CERN Document Server

    Margalef-Roig, J

    1992-01-01

    ...there are reasons enough to warrant a coherent treatment of the main body of differential topology in the realm of Banach manifolds, which is at the same time correct and complete. This book fills the gap: whenever possible the manifolds treated are Banach manifolds with corners. Corners add to the complications and the authors have carefully fathomed the validity of all main results at corners. Even in finite dimensions some results at corners are more complete and better thought out here than elsewhere in the literature. The proofs are correct and with all details. I see this book as a reliable monograph of a well-defined subject; the possibility to fall back to it adds to the feeling of security when climbing in the more dangerous realms of infinite dimensional differential geometry. Peter W. Michor

  8. Differential belongings

    DEFF Research Database (Denmark)

    Oldrup, Helene

    2014-01-01

    This paper explores suburban middle-class residents’ narratives about housing choice, everyday life and belonging in residential areas of Greater Copenhagen, Denmark, to understand how residential processes of social differentiation are constituted. Using Savage et al.’s concepts of discursive...... and not only to the area itself. In addition, rather than seeing suburban residential areas as homogenous, greater attention should be paid to differences within such areas....

  9. The prevalence of Giardia infection in dogs and cats, a systematic review and meta-analysis of prevalence studies from stool samples.

    Science.gov (United States)

    Bouzid, Maha; Halai, Kapil; Jeffreys, Danielle; Hunter, Paul R

    2015-01-30

    Giardia has a wide range of host species and is a common cause of diarrhoeal disease in humans and animals. Companion animals are able to transmit a range of zoonotic diseases to their owners including giardiasis, but the size of this risk is not well known. The aim of this study was to analyse giardiasis prevalence rates in dogs and cats worldwide using a systematic search approach. Meta-analysis enabled to describe associations between Giardia prevalence and various confounding factors. Pooled prevalence rates were 15.2% (95% CI 13.8-16.7%) for dogs and 12% (95% CI 9.2-15.3%) for cats. However, there was very high heterogeneity between studies. Meta-regression showed that the diagnostic method used had a major impact on reported prevalence with studies using ELISA, IFA and PCR reporting prevalence rates between 2.6 and 3.7 times greater than studies using microscopy. Conditional negative binomial regression found that symptomatic animals had higher prevalence rates ratios (PRR) than asymptomatic animals 1.61 (95% CI 1.33-1.94) in dogs and 1.94 (95% CI 1.47-2.56) in cats. Giardia was much more prevalent in young animals. For cats >6 months, PRR=0.47 (0.42-0.53) and in dogs of the same age group PRR=0.36 (0.32-0.41). Additionally, dogs kept as pets were less likely to be positive (PRR=0.56 (0.41-0.77)) but any difference in cats was not significant. Faecal excretion of Giardia is common in dogs and slightly less so in cats. However, the exact rates depend on the diagnostic method used, the age and origin of the animal. What risk such endemic colonisation poses to human health is still unclear as it will depend not only on prevalence rates but also on what assemblages are excreted and how people interact with their pets. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  10. Genetic characterizations of Giardia duodenalis in sheep and goats in Heilongjiang Province, China and possibility of zoonotic transmission.

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    Weizhe Zhang

    Full Text Available BACKGROUND: Giardia duodenalis is a widespread intestinal protozoan of both humans and mammals. To date, few epidemiological studies have assessed the potential and importance of zoonotic transmission; and the human giardiasis burden attributable to G. duodenalis of animal origin is unclear. No information about occurrence and genotyping data of sheep and goat giardiasis is available in China. The aim of the present study was to determine prevalence and distribution of G. duodenalis in sheep and goats in Heilongjiang Province, China, and to characterize G. duodenalis isolates and assess the possibility of zoonotic transmission. METHODOLOGY/PRINCIPAL FINDINGS: A total of 678 fecal specimens were collected from sheep and goats on six farms ranging in age from one month to four years in Heilongjiang Province, China. The average prevalence of G. duodenalis infection was 5.0% (34/678 by microscopy after Lugol's iodine staining, with 5.6% (30/539 for the sheep versus 2.9% (4/139 for the goats. Molecular analysis was conducted on 34 G. duodenalis isolates based on the triosephosphate isomerase (tpi gene. 29 tpi gene sequences were successfully obtained and identified as assemblages A (n = 4, B (n = 2 and E (n = 23. High heterogeneity was observed within assemblage E at the tpi locus, with five novel subtypes found out of seven subtypes. Two subtypes of assemblage A were detected, including subtype AI (n = 3 and a novel subtype (designated as subtype AIV (n = 1. Two assemblage B isolates were identical to each other in the tpi gene sequences. CONCLUSIONS/SIGNIFICANCE: This is the first report of G. duodenalis infections in sheep and goats in China. The present data revealed the unique endemicity on prevalence, distribution and genetic characterization of G. duodenalis in sheep and goats in Heilongjiang Province. The findings of assemblages A and B in sheep and goats implied the potential of zoonotic transmission.

  11. Prevalence and genetic characterization of Cryptosporidium species and Giardia duodenalis in lambs in Oromia Special Zone, Central Ethiopia.

    Science.gov (United States)

    Wegayehu, Teklu; Karim, Md Robiul; Li, Junqiang; Adamu, Haileeyesus; Erko, Berhanu; Zhang, Longxian; Tilahun, Getachew

    2017-01-17

    Cryptosporidium and Giardia duodenalis are gastro-intestinal parasites that infect human and animals worldwide. Both parasites share a broad host range and are believed to be zoonosis. The aim of this study was to identify the species of Cryptosporidium and assemblages of G. duodenalis in lambs and to elucidate their role in zoonotic transmission. A total of 389 fecal samples were collected from lambs and screened by microscopy and nested PCR targeting the small-subunit ribosomal RNA for Cryptosporidium; and the small-subunit ribosomal RNA, triose phosphate isomerase, β-giardin, and glutamate dehydrogenase genes for G. duodenalis. The prevalence of Cryptosporidium and G. duodenalis was 2.1% (8/389) and 2.6% (10/389), respectively. The infection rate at the three study sites ranged from 1.3 to 3.1% for Cryptosporidium and 1.6 to 3.9% for G. duodenalis; but variation was not statistically significant (p > 0.05). The finding also showed that there is no sex and age group associated difference in the occurrence of Cryptosporidium and G. duodenalis infections in lambs. Sequence analysis revealed that lambs were mono-infection with C. ubiquitum and G. duodenalis assemblage E. The analysis also indicated the presence of genetic variation within isolates of assemblage E; with 4 of them are novel genotypes at the small-subunit ribosomal RNA, β-giardin, and glutamate dehydrogenase genes. The findings of the current study showed that lambs are capable of harboring C. ubiquitum and G. duodenalis assemblage E. This finding suggests that lambs might be sources for potentially zoonotic Cryptosporidium species. This was first molecular study in lambs and contributes to a better understanding of the epidemiology of Cryptosporidium and G. duodenalis in central Ethiopia.

  12. Cryptosporidium spp. and Giardia duodenalis as pathogenic contaminants of water in Galicia, Spain: the need for safe drinking water.

    Science.gov (United States)

    Castro-Hermida, José Antonio; González-Warleta, Marta; Mezo, Mercedes

    2015-01-01

    The objectives of this cross-sectional study were to detect the presence of Cryptosporidium spp. and Giardia duodenalis in drinking water treatments plants (DWTPs) in Galicia (NW Spain) and to identify which species and genotype of these pathogenic protozoans are present in the water. Samples of untreated water (surface or ground water sources) and of treated drinking water (in total, 254 samples) were collected from 127 DWTPs and analysed by an immunofluorescence antibody test (IFAT) and by PCR. Considering the untreated water samples, Cryptosporidium spp. were detected in 69 samples (54.3%) by IFAT, and DNA of this parasite was detected in 57 samples (44.8%) by PCR, whereas G. duodenalis was detected in 76 samples (59.8%) by IFAT and in 56 samples (44.0%) by PCR. Considering the treated drinking water samples, Cryptosporidium spp. was detected in 52 samples (40.9%) by IFAT, and the parasite DNA was detected in 51 samples (40.1%) by PCR, whereas G. duodenalis was detected in 58 samples (45.6%) by IFAT and in 43 samples (33.8%) by PCR. The percentage viability of the (oo)cysts ranged between 90.0% and 95.0% in all samples analysed. Cryptosporidium andersoni, C. hominis, C. parvum and assemblages A-I, A-II, E of G. duodenalis were identified. The results indicate that Cryptosporidium spp. and G. duodenalis are widespread in the environment and that DWTPs are largely ineffective in reducing/inactivating these pathogens in drinking water destined for human and animal consumption in Galicia. In conclusion, the findings suggest the need for better monitoring of water quality and identification of sources of contamination. Copyright © 2014 Elsevier GmbH. All rights reserved.

  13. Quantitative and temporal analyses of murine antibody response in serum and gut secretions to infection with Giardia muris.

    Science.gov (United States)

    Snider, D P; Underdown, B J

    1986-04-01

    We analyzed the appearance and level of Giardia muris-specific antibody of immunoglobulin A (IgA), IgG, and IgM isotypes, at weekly intervals, over the course of a 7-week infection in BALB/c and C57BL/6 mice. Using sensitive immunoradiometric assays, we observed that IgA antibody was the only detectable anti-G. muris antibody in intestinal secretions throughout the course of infection. No secreted IgG or IgM anti-G. muris antibody was detected even in concentrated intestinal secretions. The expulsion of G. muris by the mice was associated closely with the appearance and increasing levels of secreted anti-G. muris IgA antibody. Both IgG and IgA serum antibody to G. muris were detected, but no serum IgM antibody was detected. Serum IgA and IgG anti-G. muris antibody remained at high levels up to 10 weeks following clearance of the parasite. An interesting observation indicated that serum IgA antibody to G. muris developed more slowly in response to infection than secreted IgA antibody. An analysis of the molecular weight distribution of total serum IgA in infected mice determined that infection produced a transient but significant shift in serum IgA to high-molecular-weight (greater than or equal to dimeric IgA) forms. The results indicate that a substantial IgA antibody response occurs in sera and in gut secretions of G. muris-resistant mice and that IgA antibody is the dominant and possibly the only effector antibody active in intestinal secretions during G. muris infection in mice.

  14. A meta-analysis of the effectiveness of albendazole compared with metronidazole as treatments for infections with Giardia duodenalis.

    Directory of Open Access Journals (Sweden)

    Shahram Solaymani-Mohammadi

    2010-05-01

    Full Text Available Metronidazole is the most commonly used drug for the treatment of giardiasis in humans. In spite of its therapeutic efficacy for giardiasis, low patient compliance, especially in children, side effects, and the emergence of metronidazole-resistant strains may restrict its use. Albendazole has been used to treat Giardia duodenalis infections in recent years. However, efficacy studies in vivo and in vitro have produced diverse results as to its effectiveness. A moderately benign side effect profile, combined with established efficacy against many helminths, renders it promising for treatment of giardiasis in humans.We performed a search in the PubMed, Scopus, EMBASE, the ISI Web of Science, LILIACS, and Cochrane Controlled Trials Register for trials published before February 2010 as well as in references of relevant research and review articles. Eight randomized clinical trials (including 900 patients comparing the effectiveness of albendazole with that of metronidazole were included in meta-analysis. After extracting and validating the data, the pooled risk ratio (RR was calculated using an inverse-variance random-effects model. Albendazole was found to be equally as effective as metronidazole in the treatment of giardiasis in humans (RR 0.97; 95% CI, 0.93, 1.01. In addition, safety analysis suggested that patients treated with albendazole had a lower risk of adverse effects compared with those who received metronidazole (RR 0.36; 95% CI, 0.10, 1.34, but limitations of the sample size precluded a definite conclusion.The effectiveness of albendazole, when given as a single dose of 400 mg/day for 5 days, was comparable to that of metronidazole. Patients treated with albendazole tended to have fewer side effects compared with those who took metronidazole. Given the safety, effectiveness, and low costs of albendazole, this drug could be potentially used as an alternative and/or a replacement for the existing metronidazole therapy protocols in the

  15. Giardia intestinalis and nutritional status in children participating in the complementary nutrition program, Antioquia, Colombia, May to October 2006 Giardia intestinalis e estado nutricional em crianças participantes do programa de nutrição complementar, melhoramento alimentar e nutricional da Antioquia (MANA - Instituto Colombiano de Bem-Estar Familiar (ICBF, Antióquia, Colombia, maio a outubro de 2006

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    Jorge H. Botero-Garcés

    2009-06-01

    Full Text Available Giardia intestinalis infection is prevalent throughout the world and widely distributed in developing countries. In general, children display serious consequences to their state of health, including slow height-weight development; therefore, the main aim of this study was to determine the association between Giardia infection and the nutritional status of children who participate in the program of complementary feeding (Mejoramiento Alimentario y Nutricional de Antioquia (MANA - Instituto Colombiano de Bienestar Familiar (ICBF. A cross-sectional study examining the association of giardiasis with nutritional status was conducted. A total of 2035 children aged eight months to six years-old were studied. Data were collected using structured questionnaires, anthropometric measurements and laboratory analysis of blood and stool samples. Analysis of the results showed that 27.6% of children were infected with G. intestinalis, while 8.1% and 1.9% were mildly and significantly underweight, respectively, and 14.1% presented stunting. Giardiasis was statistically identified as a strong predictor of stunting in this study population.A infecção pela Giardia intestinalis está amplamente distribuída no mundo apresentando a maior prevalência nos países em desenvolvimento. Em crianças, esta parasitose pode ter conseqüências graves no estado geral de saúde assim como no ganho de peso e estatura. O objetivo desta pesquisa foi estabelecer a associação entre a infecção com Giardia e o estado nutricional das crianças beneficiárias do programa de complementação alimentar - MANA. Um estudo de corte no qual foram avaliadas 2035 crianças entre os oito meses e os seis anos de idade foi realizado. A informação foi obtida a partir de questionários estruturados, medições antropométricas e exame de fezes. Os resultados mostraram que 27,6% das crianças estavam infectadas com Giardia intestinalis, das quais 8,1% apresentaram desnutrição moderada

  16. Differential geometry

    CERN Document Server

    Ciarlet, Philippe G

    2007-01-01

    This book gives the basic notions of differential geometry, such as the metric tensor, the Riemann curvature tensor, the fundamental forms of a surface, covariant derivatives, and the fundamental theorem of surface theory in a selfcontained and accessible manner. Although the field is often considered a classical one, it has recently been rejuvenated, thanks to the manifold applications where it plays an essential role. The book presents some important applications to shells, such as the theory of linearly and nonlinearly elastic shells, the implementation of numerical methods for shells, and

  17. Differential equations

    CERN Document Server

    Tricomi, FG

    2013-01-01

    Based on his extensive experience as an educator, F. G. Tricomi wrote this practical and concise teaching text to offer a clear idea of the problems and methods of the theory of differential equations. The treatment is geared toward advanced undergraduates and graduate students and addresses only questions that can be resolved with rigor and simplicity.Starting with a consideration of the existence and uniqueness theorem, the text advances to the behavior of the characteristics of a first-order equation, boundary problems for second-order linear equations, asymptotic methods, and diff

  18. Differential topology

    CERN Document Server

    Guillemin, Victor

    2010-01-01

    Differential Topology provides an elementary and intuitive introduction to the study of smooth manifolds. In the years since its first publication, Guillemin and Pollack's book has become a standard text on the subject. It is a jewel of mathematical exposition, judiciously picking exactly the right mixture of detail and generality to display the richness within. The text is mostly self-contained, requiring only undergraduate analysis and linear algebra. By relying on a unifying idea-transversality-the authors are able to avoid the use of big machinery or ad hoc techniques to establish the main

  19. Helium ion microscopy and ultra-high-resolution scanning electron microscopy analysis of membrane-extracted cells reveals novel characteristics of the cytoskeleton of Giardia intestinalis.

    Science.gov (United States)

    Gadelha, Ana Paula Rocha; Benchimol, Marlene; de Souza, Wanderley

    2015-06-01

    Giardia intestinalis presents a complex microtubular cytoskeleton formed by specialized structures, such as the adhesive disk, four pairs of flagella, the funis and the median body. The ultrastructural organization of the Giardia cytoskeleton has been analyzed using different microscopic techniques, including high-resolution scanning electron microscopy. Recent advances in scanning microscopy technology have opened a new venue for the characterization of cellular structures and include scanning probe microscopy techniques such as ultra-high-resolution scanning electron microscopy (UHRSEM) and helium ion microscopy (HIM). Here, we studied the organization of the cytoskeleton of G. intestinalis trophozoites using UHRSEM and HIM in membrane-extracted cells. The results revealed a number of new cytoskeletal elements associated with the lateral crest and the dorsal surface of the parasite. The fine structure of the banded collar was also observed. The marginal plates were seen linked to a network of filaments, which were continuous with filaments parallel to the main cell axis. Cytoplasmic filaments that supported the internal structures were seen by the first time. Using anti-actin antibody, we observed a labeling in these filamentous structures. Taken together, these data revealed new surface characteristics of the cytoskeleton of G. intestinalis and may contribute to an improved understanding of the structural organization of trophozoites. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Performance of Glutamate Dehydrogenase and Triose Phosphate Isomerase Genes in the Analysis of Genotypic Variability of Isolates of Giardia duodenalis from Livestocks

    Science.gov (United States)

    Fava, Natália M. N.; Soares, Rodrigo M.; Scalia, Luana A. M.; Kalapothakis, Evanguedes; Pena, Isabella F.; Vieira, Carlos U.; Faria, Elaine S. M.; Cunha, Maria J.; Couto, Talles R.; Cury, Márcia Cristina

    2013-01-01

    Giardia duodenalis is a small intestinal protozoan parasite of several terrestrial vertebrates. This work aims to assess the genotypic variability of Giardia duodenalis isolates from cattle, sheep and pigs in the Southeast of Brazil, by comparing the standard characterization between glutamate dehydrogenase (gdh) and triose phosphate isomerase (tpi) primers. Fecal samples from the three groups of animals were analyzed using the zinc sulphate centrifugal flotation technique. Out of 59 positive samples, 30 were from cattle, 26 from sheep and 3 from pigs. Cyst pellets were stored and submitted to PCR and nested-PCR reactions with gdh and tpi primers. Fragment amplification of gdh and tpi genes was observed in 25 (42.4%) and 36 (61.0%) samples, respectively. Regarding the sequencing, 24 sequences were obtained with gdh and 20 with tpi. For both genes, there was a prevalence of E specific species assemblage, although some isolates have been identified as A and B, by the tpi sequencing. This has also shown a larger number of heterogeneous sequences, which have been attribute to mixed infections between assemblages B and E. The largest variability of inter-assemblage associated to the frequency of heterogeneity provided by tpi sequencing reinforces the polymorphic nature of this gene and makes it an excellent target for studies on molecular epidemiology. PMID:24308010

  1. Molecular Genotyping of Giardia duodenalis Isolates from Symptomatic Individuals Attending Two Major Public Hospitals in Madrid, Spain.

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    Aida de Lucio

    Full Text Available The flagellate protozoan Giardia duodenalis is an enteric parasite causing human giardiasis, a major gastrointestinal disease of global distribution affecting both developing and industrialised countries. In Spain, sporadic cases of giardiasis have been regularly identified, particularly in pediatric and immigrant populations. However, there is limited information on the genetic variability of circulating G. duodenalis isolates in the country.In this longitudinal molecular epidemiological study we report the diversity and frequency of the G. duodenalis assemblages and sub-assemblages identified in 199 stool samples collected from 184 individual with symptoms compatible with giardiasis presenting to two major public hospitals in Madrid for the period December 2013-January 2015. G. duodenalis cysts were initially detected by conventional microscopy and/or immunochomatography on stool samples. Confirmation of the infection was performed by direct immunofluorescence and real-time PCR methods. G. duodenalis assemblages and sub-assemblages were determined by multi-locus genotyping of the glutamate dehydrogenase (GDH and β-giardin (BG genes of the parasite. Sociodemographic and clinical features of patients infected with G. duodenalis were also analysed.Of 188 confirmed positive samples from 178 giardiasis cases a total of 124 G. duodenalis isolates were successfully typed at the GDH and/or the BG loci, revealing the presence of sub-assemblages BIV (62.1%, AII (15.3%, BIII (4.0%, AI (0.8%, and AIII (0.8%. Additionally, 6.5% of the isolates were only characterised at the assemblage level, being all of them assigned to assemblage B. Discordant genotype results AII/AIII or BIII/BIV were also observed in 10.5% of DNA isolates. A large number of multi-locus genotypes were identified in G. duodenalis assemblage B, but not assemblage A, isolates at both the GDH and BG loci, confirming the high degree of genetic variability observed in other molecular surveys

  2. Infection rate of Giardia duodenalis, Cryptosporidium spp. and Enterocytozoon bieneusi in cashmere, dairy and meat goats in China.

    Science.gov (United States)

    Peng, Xian-Qi; Tian, Ge-Ru; Ren, Guan-Jing; Yu, Zheng-Qing; Lok, James Barron; Zhang, Long-Xian; Wang, Xue-Ting; Song, Jun-Ke; Zhao, Guang-Hui

    2016-07-01

    Cryptosporidiosis, microsporidiosis, and giardiasis contribute significantly to the high burden of zoonotic diarrhea worldwide. Goats constitute an important species in animal agriculture by providing cashmere wool, meat, and dairy products for human consumption. However, zoonotic pathogens with the potential to cause morbidity and to degrade production have been reported frequently in goats recently. The present study examined 629 fecal specimens from goats, including 315 cashmere goats, 170 dairy goats and 144 meat goats, in multiple cities of Shaanxi and Henan provinces, northwestern and central China, to investigate the infection rate and species/assemblages/genotypes of Giardia duodenalis, Cryptosporidium spp. and Enterocytozoon bieneusi. Of these samples, 274 (43.6%) were positive for three zoonotic pathogens, including 80 (12.7%), 104 (16.5%) and 179 (28.5%) for G. duodenalis, Cryptosporidium spp. and E. bieneusi, respectively. Infections with G. duodenalis, Cryptosporidium spp. and E. bieneusi existed in meat, dairy and cashmere goats, with the highest infection rate of each pathogen being observed in meat goats. DNA sequencing of the SSU rRNA gene from 104 Cryptosporidium-positive specimens revealed existence of Cryptosporidium xiaoi, and the zoonotic parasites Cryptosporidium parvum and Cryptosporidium ubiquitum. Genotyping of G. duodenalis based on the triosephosphate isomerase (TPI) gene identified parasites from zoonotic assemblage A in four cashmere goats and the animal-adapted assemblage E in a group of 76 goats that included cashmere, dairy and meat animals. Polymorphisms in the ribosomal internal transcribed spacer characterized E. bieneusi genotype CHG1 and a novel genotype named as SX1 in both dairy and cashmere goats, genotypes CHS7 and COSI in meat goats, the genotype CHG2 in dairy goats, and the human-pathogenic genotype BEB6 in dairy and meat goats. This is the first detailed study to compare infection rate of the zoonotic protozoan pathogens

  3. Reducing occurrence of Giardia duodenalis in children living in semiarid regions: impact of a large scale rainwater harvesting initiative.

    Science.gov (United States)

    Fonseca, Jacqueline Evangelista; Carneiro, Mariângela; Pena, João Luiz; Colosimo, Enrico A; da Silva, Nívea Bispo; da Costa, André Gabriel F C; Moreira, Luciano E; Cairncross, Sandy; Heller, Léo

    2014-06-01

    In Brazil, about two million people living in rural semiarid regions were benefited with the construction of rainwater cement cisterns, as an initiative from the program "One Million Cisterns" (P1MC). Nevertheless, few epidemiological studies have been conducted to assess health risks or protection effects associated with consumption of this water source. The aim of this study was to evaluate whether access to rainwater harvesting cisterns is associated with the decrease in the occurrence of Giardia duodenalis infections in children, compared to other children living in households supplied by other water sources. A quasi-experimental study with two concurrent cohorts was developed in two rural municipalities of the semiarid region of Brazil. A sample of 664 children, aged between 4 months and 5 years old, was followed up, of which 332 had access to rainwater cisterns (cistern group) and 332 did not, having water supplied from alternative sources (comparison group). In a period of approximately one year (2010) intestinal parasites were investigated in feces three times. The prevalence of G. duodenalis in children from the cistern group ranged from 4.8 to 10.5%, while the prevalence in the comparison group ranged from 7.6 to 16.7%. Multivariate analysis (GEE) showed a higher risk of G. duodenalis infection in children who did not have access to rainwater cisterns, when compared to children who did (OR 1.72; 95% CI 1.14-2.59). The other variables associated with G. duodenalis infection were: number of rooms per house (OR 0.89; 95% CI 0.80-0.99); family income (OR0.48; 95% CI 0.26-0.88); birth order (OR 1.72; 95% CI 1.17-2.51); preterm children (OR 1.70; 95% CI 1.19-2.43); and improper hand hygiene prior to food preparation (OR 4.78; 95% CI 1.95-11.76). Ownership of a rainwater cistern is associated with a lower prevalence of G. duodenalis infection in children after adjustment for environmental and family-related factors. Nevertheless, the study suggests the necessity

  4. Reducing occurrence of Giardia duodenalis in children living in semiarid regions: impact of a large scale rainwater harvesting initiative.

    Directory of Open Access Journals (Sweden)

    Jacqueline Evangelista Fonseca

    2014-06-01

    Full Text Available BACKGROUND: In Brazil, about two million people living in rural semiarid regions were benefited with the construction of rainwater cement cisterns, as an initiative from the program "One Million Cisterns" (P1MC. Nevertheless, few epidemiological studies have been conducted to assess health risks or protection effects associated with consumption of this water source. The aim of this study was to evaluate whether access to rainwater harvesting cisterns is associated with the decrease in the occurrence of Giardia duodenalis infections in children, compared to other children living in households supplied by other water sources. METHODOLOGY/PRINCIPAL FINDINGS: A quasi-experimental study with two concurrent cohorts was developed in two rural municipalities of the semiarid region of Brazil. A sample of 664 children, aged between 4 months and 5 years old, was followed up, of which 332 had access to rainwater cisterns (cistern group and 332 did not, having water supplied from alternative sources (comparison group. In a period of approximately one year (2010 intestinal parasites were investigated in feces three times. The prevalence of G. duodenalis in children from the cistern group ranged from 4.8 to 10.5%, while the prevalence in the comparison group ranged from 7.6 to 16.7%. Multivariate analysis (GEE showed a higher risk of G. duodenalis infection in children who did not have access to rainwater cisterns, when compared to children who did (OR 1.72; 95% CI 1.14-2.59. The other variables associated with G. duodenalis infection were: number of rooms per house (OR 0.89; 95% CI 0.80-0.99; family income (OR0.48; 95% CI 0.26-0.88; birth order (OR 1.72; 95% CI 1.17-2.51; preterm children (OR 1.70; 95% CI 1.19-2.43; and improper hand hygiene prior to food preparation (OR 4.78; 95% CI 1.95-11.76. CONCLUSIONS/SIGNIFICANCE: Ownership of a rainwater cistern is associated with a lower prevalence of G. duodenalis infection in children after adjustment for

  5. Detection and molecular diversity of Giardia duodenalis and Cryptosporidium spp. in sheltered dogs and cats in Northern Spain.

    Science.gov (United States)

    Gil, Horacio; Cano, Lourdes; de Lucio, Aida; Bailo, Begoña; de Mingo, Marta Hernández; Cardona, Guillermo A; Fernández-Basterra, José A; Aramburu-Aguirre, Juan; López-Molina, Nuria; Carmena, David

    2017-06-01

    Domestic dogs and cats may act as natural reservoirs of a large number of zoonotic pathogens, including the enteric parasites Giardia duodenalis and Cryptosporidium spp., the most relevant protozoan species causing gastrointestinal disease worldwide. A cross-sectional epidemiological study aiming to assess the prevalence and molecular diversity of G. duodenalis and Cryptosporidium spp. was conducted in an animal rescue centre in the province of Álava (Northern Spain). A total of 194 and 65 faecal dropping samples from individual dogs and cats, respectively, were collected between November 2013 and June 2016. G. duodenalis cysts and Cryptosporidium spp. oocysts were detected by direct fluorescence microscopy and PCR-based methods targeting the small subunit ribosomal RNA gene of these parasites. Overall, G. duodenalis and Cryptosporidium spp. were detected in 33% (63/194) and 4.1% (8/194) of dogs, and 9.2% (6/65) and 4.6% (3/65) of cats, respectively. G. duodenalis and Cryptosporidium co-infections were observed in 1.5% (3/194) of dogs, but not in cats. No significant differences in infection rates could be demonstrated among dogs or cats according to their sex, age group, status, or geographical origin. Multi-locus sequence-based genotyping of the glutamate dehydrogenase and β-giardin genes of G. duodenalis allowed the characterization of 19 canine isolates that were unambiguously assigned to sub-assemblages AII (n=7), BIII (n=1), and BIV (n=7), and assemblages C (n=3) and D (n=1). Two feline isolates were genotyped as assemblages A and F, respectively. No mixed assemblage or sub-assemblage infections were identified. C. canis (n=5) and C. hominis (n=1) were the Cryptosporidium species found in dogs, whereas C. felis (n=1) was identified in cats. The finding of G. duodenalis sub-assemblages AII, BIII, and BIV circulating in dogs (but not cats) may have zoonotic potential, although most of the AII and BIV isolates sub-genotyped corresponded to genetic variants not

  6. Ocorrência de Giardia, Cryptosporidium e microsporídios em animais silvestres em área de desmatamento no Estado de São Paulo, Brasil Occurrence of Giardia, Cryptosporidium and microsporidia in wild animals from a deforestation area in the state of São Paulo, Brazil

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    Maria Anete Lallo

    2009-08-01

    Full Text Available A ocorrência de Giardia, Cryptosporidium e microsporídios foi investigada por meio da análise de 98 amostras fecais de animais silvestres capturados em uma área de desmatamento para a construção das barragens de Paraitinga e Biritiba, localizadas nos Municípios de Mogi das Cruzes, Salesópolis e Biritiba-Mirim, no Estado de São Paulo. As amostras foram obtidas de 46 roedores, 21 marsupiais, 16 sapos, nove morcegos, três primatas e três lagartos. As técnicas de centrífugo-flutuação com sulfato de zinco, de Kinyoun e a coloração de Gram-Chromotrope foram utilizadas, respectivamente, para a pesquisa de Giardia, de Cryptosporidium e de microsporídios. O total de animais parasitados por um dos protozoários investigados foi de 17,35% (17/98. Cistos de Giardia foram encontrados em amostras fecais de dois pequenos roedores da espécie Coendou villosus (ouriço-cacheiro. Os três animais positivos para Cryptosporidium foram roedores das espécies Akodon montensis, Thaptomys nigrita (ambos conhecidos como ratos do mato e Sciurus aestuans (serelepe ou caxinguelê. Esporos de microsporídios foram encontrados nas fezes de 12 animais, sendo seis roedores das espécies Oligoryzomys sp.(um, Akodon montensis (três e Coendou villosus (dois, três marsupiais pertencentes às espécies Didelphis aurita (dois e Marmosops incanus (um e três morcegos da espécie Diphylla ecaudata. Este é o primeiro relato de microsporidiose em animais silvestres no Brasil. A presente investigação enfatiza a importância de animais silvestres, particularmente pequenos mamíferos, como potenciais fontes de infecção desses protozoários para outras populações animais, incluindo o homem, em áreas de desmatamento.The occurrence of Giardia, Cryptosporidium and microsporidia was investigated in 98 faecal specimens from wildlife animals, captured in an area of deforestation for the construction of two water reservoirs (Paraitinga and Biritiba, located in the

  7. Detecção de oocistos de Cryptosporidium spp. e cistos de Giardia spp. em amostras de esgoto bruto ou tratado: avaliação crítica dos métodos Detection of Cryptosporidium spp. oocysts and Giardia spp. cysts in raw and effluent wastewater: critical evaluation of methods

    Directory of Open Access Journals (Sweden)

    Luciana Urbano dos Santos

    2011-06-01

    Full Text Available Neste trabalho, avaliou-se a eficiência dos métodos centrífugo-concentração e filtração em membrana, na detecção de oocistos de Cryptosporidium spp. e cistos de Giardia spp. em amostras de esgoto bruto e tratado, provenientes de um sistema de lodos ativados (estação de tratamento de esgoto, Samambaia, Campinas, em São Paulo. As amostras foram coletadas quinzenalmente por dois anos: 53 amostras de esgoto bruto (AFL, 53 de efluente tratado sem desinfecção por luz ultravioleta (EFL e 38 de efluente tratado e desinfetado por luz ultravioleta (EFL+UV. Cistos de Giardia spp. foram encontrados em 90,5% das amostras AFL; em 96,2%, de EFL; e em 94,7%, de EFL+UV. Oocistos de Cryptosporidium spp. foram detectados em 6,4% das amostras AFL e em 2,6 % de EFL+UV. Ambos os métodos mostraram-se eficientes na detecção destes protozoários em todos os tipos de amostras, além de apresentarem baixo custo por análise.In this study, the efficiency of centrifuge-concentration and membrane filtrated methods was evaluated in the detection of Cryptosporidium spp. oocysts and Giardia spp. cysts in raw or treated wastewater samples, from activated sludge systems (ETE - Samambaia, Campinas, in São Paulo. The samples were collected once a fortnight for two years: 53 samples of influent (AFL, 53 samples of treated effluent without ultraviolet disinfection (EFL, and 38 samples of treated effluent with ultraviolet disinfection (EFL+UV. Giardia spp. cysts were found in 90.5% of the AFL samples; in 96.2% of the samples, EFL; and in 94.7%, EFL+UV. Cryptosporidium spp. oocysts were detected in 6.4% of AFL samples and 2.6% of EFL+UV. Both methods showed efficiency when detecting protozoa in all types of samples, besides having low costs by analysis.

  8. Estudio de los patrones de ubiquitinación y la actividad de proteólisis específica del proteosoma en Giardia Intestinalis / Study of the ubiquitination patterns and the specific activity of the proteasome in Giardia Intestinalis

    OpenAIRE

    Chaparro Gutiérrez, Jenny Jovana

    2011-01-01

    El parásito protozoario Giardia intestinalis es un agente causante de diarrea en humanos alrededor del mundo. Además de su importancia como patógeno es un eucariota que divergió tempranamente y constituye un importante modelo de estudio de procesos celulares básicos. Durante su ciclo de vida, G. intestinalis, presenta dos procesos de diferenciación, la enquistación y la exquistación, los cuales involucran modificaciones intracelulares, transcripción de nuevos genes, síntesis y probablemente ...

  9. Genotipagem de isolados de Giardia duodenalis de primatas não humanos mantidos em zoológico do Brasil

    OpenAIRE

    David, Erica Boarato; Patti, Mariella; Coradi, Silvana Torossian; Oliveira-Sequeira, Teresa Cristina Goulart; Ribolla, Paulo Eduardo Martins; Guimaraes, Semiramis

    2014-01-01

    A pesquisa de infecções por Giardia e a caracterização genotípica deste protozoário foi realizada em primatas não humanos (PNH) mantidos em Zoológico a fim de avaliar o seu potencial zoonótico. As amostras dos animais consistiram de fezes colhidas do piso de 22 baias onde eram mantidos 47 primatas de 18 diferentes espécies. Exames coproparasitológicos foram realizados pelos métodos de concentração por sedimentação e centrífugo-flutuação e revelaram a presença dos seguintes parasitas e suas re...

  10. Intestinal parasites and genotyping of Giardia duodenalis in children: first report of genotype B in isolates from human clinical samples in Mexico

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    Julio César Torres-Romero

    2014-06-01

    Full Text Available Giardia duodenalis is one of the most prevalent enteroparasites in children. This parasite produces several clinical manifestations. The aim of this study was to determine the prevalence of genotypes of G. duodenalis causing infection in a region of southeastern Mexico. G. duodenalis cysts were isolated (33/429 from stool samples of children and molecular genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP analysis, targeting the triosephosphate isomerase ( tpi and glutamate dehydrogenase ( gdh genes. The tpi gene was amplified in all of the cyst samples, either for assemblage A (27 samples or assemblage B (6 samples. RFLP analysis classified the 27 tpi -A amplicons in assemblage A, subgenotype I. Samples classified as assemblage B were further analysed using PCR-RFLP of the gdh gene and identified as assemblage B, subgenotype III. To our knowledge, this is the first report of assemblage B of G. duodenalis in human clinical samples from Mexico.

  11. Studies on the resistance/reactivation of Giardia muris cysts and Cryptosporidium parvum oocysts exposed to medium-pressure ultraviolet radiation.

    Science.gov (United States)

    Belosevic, M; Craik, S A; Stafford, J L; Neumann, N F; Kruithof, J; Smith, D W

    2001-10-16

    The ex vivo and in vivo reactivation of Giardia muris cysts and Cryptosporidium parvum oocysts after exposure to different doses of ultraviolet (UV) radiation was determined using animal infectivity. The infectivity of UV-treated parasites stored for 1-4 days (G. muris) or 1-17 days (C. parvum) at room temperature in the dark was similar to that of organisms administered immediately after UV treatment, indicating that the parasites did not reactivate ex vivo. In contrast, we observed in vivo reactivation of G. muris in three of seven independent animal infectivity experiments, when parasites were treated with relatively low doses of medium-pressure UV (muris cysts and C. parvum oocysts exposed to medium-pressure UV doses of 60 mJ/cm(2) or higher did not exhibit resistance to and/or reactivation following treatment. This suggests that when appropriate doses of UV are used, significant and permanent inactivation of these parasites may be achieved.

  12. Evaluation of the effects of albendazole and metronidazole on the ultrastructure of Giardia duodenalis, Trichomonas vaginalis and Spironucleus muris using transmission electron microscopy.

    Science.gov (United States)

    Oxberry, M E; Thompson, R C; Reynoldson, J A

    1994-08-01

    The three closely related parasitic protozoa, Giardia duodenalis, Trichomonas vaginalis and Spironucleus muris, all have very different sensitivities to albendazole and metronidazole. Ultrastructural studies reveal that the cytoskeletal elements of the ventral disk in G. duodenalis are affected by albendazole, whereas the other two parasites, neither of which possess this structure, are not affected by albendazole to the same extent. This suggests that albendazole may be having its primary affect on G. duodenalis by binding to cytoskeletal proteins and ultimately causing death of the parasite. Death may be occurring as the parasite loses its ability to adhere to the intestinal villi and obtain nutrients. Metronidazole showed a different pattern of activity against the three parasites. The evidence obtained from these ultrastructural studies supports the current theory that metronidazole adversely affects protozoa by disrupting inner cell membranes.

  13. Giardia duodenalis assemblages and Entamoeba species infecting non-human primates in an Italian zoological garden: zoonotic potential and management traits

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    Di Cave David

    2011-10-01

    Full Text Available Abstract Background Giardia duodenalis and Entamoeba spp. are among the most common intestinal human protozoan parasites worldwide and they are frequently reported in captive non-human primates (NHP. From a public health point of view, infected animals in zoos constitute a risk for animal caretakers and visitors. In this study we carried out the molecular identification of G. duodenalis and Entamoeba spp. from nine species of primates housed in the zoological garden of Rome, to better ascertain their occurrence and zoonotic potential. Results G. duodenalis was found only in Lemur catta (47.0%. Entamoeba spp. were detected in all species studied, with the exception of Eulemur macaco and Varecia rubra. The number of positive pools ranged from 5.9% in L. catta to 81.2% in Mandrillus sphinx; in Pan troglodytes the observed prevalence was 53.6%. A mixed Entamoeba-Giardia infection was recorded only in one sample of L. catta. All G. duodenalis isolates belonged to the zoonotic assemblage B, sub assemblage BIV. Three Entamoeba species were identified: E. hartmanni, E. coli and E. dispar. Conclusions Our results highlight the importance of regularly testing animals kept in zoos for the diagnosis of zoonotic parasites, in order to evaluate their pathogenic role in the housed animals and the zoonotic risk linked to their presence. A quick detection of the arrival of pathogens into the enclosures could also be a prerequisite to limit their spread into the structure via the introduction of specific control strategies. The need for molecular identification of some parasite species/genotype in order to better define the zoonotic risk is also highlighted.

  14. Identical assemblage of Giardia duodenalis in humans, animals and vegetables in an urban area in southern Brazil indicates a relationship among them.

    Directory of Open Access Journals (Sweden)

    Cristiane Maria Colli

    Full Text Available Giardia duodenalis infects humans and other mammals by ingestion of cysts in contaminated water or food, or directly in environments with poor hygiene. Eight assemblages, designated A-H, are described for this species.We investigated by microscopy or by direct immunofluorescence technique the occurrence of G. duodenalis in 380 humans, 34 animals, 44 samples of water and 11 of vegetables. G. duodenalis cysts present in samples were genotyped through PCR-RFLP of β giardin and glutamate dehydrogenase (gdh genes and sequencing of gdh. The gdh gene was amplified in 76.5% (26/34 of the human faeces samples with positive microscopy and in 2.9% (1/34 of negative samples. In 70.4% (19/27 of the positive samples were found BIV assemblage. In two samples from dogs with positive microscopy and one negative sample, assemblages BIV, C, and D were found. Cysts of Giardia were not detected in water samples, but three samples used for vegetable irrigation showed total coliforms above the allowed limit, and Escherichia coli was observed in one sample. G. duodenalis BIV was detected in two samples of Lactuca sativa irrigated with this sample of water. BIV was a common genotype, with 100% similarity, between different sources or hosts (humans, animals and vegetables, and the one most often found in humans.This is the first study in Brazil that reports the connection among humans, dogs and vegetables in the transmission dynamics of G. duodenalis in the same geographic area finding identical assemblage. BIV assemblage was the most frequently observed among these different links in the epidemiological chain.

  15. Concentrated Differential Privacy

    OpenAIRE

    Dwork, Cynthia; Rothblum, Guy N.

    2016-01-01

    We introduce Concentrated Differential Privacy, a relaxation of Differential Privacy enjoying better accuracy than both pure differential privacy and its popular "(epsilon,delta)" relaxation without compromising on cumulative privacy loss over multiple computations.

  16. Ghrelin and melatonin as biomarkers in patients with giardiasis

    Directory of Open Access Journals (Sweden)

    Saleem Khteer Al-Hadraawy

    2016-05-01

    Full Text Available Giardia is the most frequently reported intestinal parasite worldwide. The aim of this study was to investigate the ghrelin, melatonin, glucose and cholesterol concentration in male patients infected with Giardia lamblia. We enrolled 66 patients with Giardiasis and the control groups consisted of healthy subjects (n = 30. The results demonstrated that there was a significant decrease (P < 0.05 in ghrelin levels, while the melatonin, glucose and cholesterol levels were significantly increased (P < 0.05 in giardiasis patients as compared to the healthy group. The obtained results suggest that ghrelin and melatonin could serve as biomarkers in patients infected with G. lamblia.

  17. Prevalence of Giardia sp. Cryptosporidium parvum and Cryptosporidium andersoni (syn. C. muris) [correction of Cryptosporidium parvum and Cryptosporidium muris (C. andersoni)] in 109 dairy herds in five counties of southeastern New York.

    Science.gov (United States)

    Wade, S E; Mohammed, H O; Schaaf, S L

    2000-11-01

    A cross-sectional study was undertaken to determine the prevalence of Giardia sp. (G. duodenalis group), Cryptosporidium parvum and Cryptosporidium andersoni (C. muris) [corrected] in dairy cattle in three different age groups, and to evaluate the association of age and season with prevalence. One hundred and nine dairy farms, from a total of 212 farms, in five counties of southeastern New York volunteered to participate. On these farms, 2943 fecal samples were collected from three defined age groups. The farms were randomly assigned for sampling within the four seasons of the year. Each farm was visited once during the study period from March 1993 to June 1994 to collect fecal samples. Demographic data on the study population was collected at the time of sampling by interviewing the farm owner or manager. At collection, fecal samples were scored as diarrheic or non-diarrheic, and each condition was later related to positive or negative infection with these parasites. Fecal samples were processed using a quantitative centrifugation concentration flotation technique and enumerated using bright field and phase contrast microscopy. In this study, the overall population prevalence for Giardia sp. was 8.9%; C. parvum, 0.9%; and C. muris, 1.1%. When considering animals most at the risk of infection (those younger than 6 months of age) Giardia sp. and C. parvum was found in 20.1 and 2.4% of the animals, respectively. Giardia sp. and C. muris were found in all age groups. There was no significant seasonal pattern of infection for any of these parasites.

  18. Assessment of Iodine-treated Filter Media for Removal and Inactivation of MS2 Bacteriophase Aerosols

    Science.gov (United States)

    2009-04-01

    adding chloramine - T to similar concentrations of K131I in water achieved fast and efficient incorporation of the small amount of 131I into human...Triiodide Demand-Type Disinfectant . Appl Environ Microbiol 44, 1370–1373. Foarde, K. K. and James, T . H. (2001) Determine the efficacy of antimicrobial...Fina, G. T . (1983) Effect of Resin disinfectants I3 and I5 on Giardia muris and Giardia lamblia. Appl Environ Microbiol 46, 965–969. Marchin, G. L

  19. Giardiasis in Bergen. Outbreak and clinical consequences.

    OpenAIRE

    Wensaas, Knut-Arne

    2011-01-01

    Background Giardia lamblia is a common cause of waterborne disease. It is endemic in many parts of the world, especially where sanitation is poor, but in Europe and North America it is most often encountered in outbreaks following contamination of drinking water. The first registered outbreak of giardiasis affecting a large community in Norway happened in Bergen in the autumn of 2004. The reservoir “Svartediket” was the source, and the water probably held Giardia cysts for s...

  20. Recuento y determinación de viabilidad de giardia spp. y Cryptosporidium spp. en aguas potables y residuales en la cuenca alta del rio Bogotá.

    Directory of Open Access Journals (Sweden)

    Marlén Andrea Alarcón

    2005-09-01

    Full Text Available Introducción. La transmisión de enfermedades de origen hídrico está relacionada con la contaminación de origen fecal en aguas residuales y potables. Estas enfermedades son causadas por la presencia de bacterias, virus y parásitos, los cuales generan altos porcentajes de morbimortalidad, especialmente, en la población infantil. Se han seleccionado Giardia spp. y Cryptosporidium spp. como organismos indicadores de contaminación de origen parasitario y su análisis es útil para evaluar la calidad del agua y determinar el riesgo sanitario. En Colombia se conoce poco sobre la presencia y la concentración de estos parásitos en aguas, razón por la cual es importante continuar su estudio. Objetivo. El objetivo de este trabajo fue evaluar la presencia de estos protozoos en cinco estaciones de muestreo de la cuenca alta del río Bogotá y en dos sistemas de potabilización de la misma área. Materiales y métodos. Las técnicas aplicadas para la determinación y el recuento de las formas quísticas fueron: floculación inorgánica para aguas residuales, filtración para aguas potables y pruebas de colorantes vitales para viabilidad. Resultados. Se confirmó la presencia de Cryptosporidium spp. en dos de las estaciones del río Bogotá y en las dos potabilizadoras. Giardia spp. se encontró en las dos potabilizadoras pero no en el río Bogotá. La viabilidad fue positiva para Cryptosporidium spp. en una muestra proveniente del río, y negativa para las muestras de agua potable. Conclusiones. Estos resultados muestran la presencia de protozoos en aguas potables y residuales lo cual puede generar riesgo sanitario para la población de dicha zona.

  1. Serodiagnóstico de giardiosis: identificación de inmunoglobulina G anti-Giardia duodenalis en suero mediante ELISA

    Directory of Open Access Journals (Sweden)

    Sofía Duque

    2001-09-01

    Full Text Available El diagnóstico de la infección por Giardia duodenalis se basa en la identificación de quistes o trofozoítos en materia fecal, alcanzando una sensibilidad máxima de 85% en muestras seriadas, debido a la excreción intermitente de quistes. Aunque la determinación de anticuerpos no permite diferenciar entre una infección pasada y una reciente, si podría ayudar en el diagnóstico diferencial. El presente estudio tuvo como objetivos estandarizar y evaluar una prueba inmunoenzimática (ELISA para la detección de anticuerpos tipo IgG anti-Giardia duodenalis en sueros de pacientes con la infección. La preparación del antigeno se hizo a partir de trofozoitos cultivados que, inicialmente, fueron obtenidos del intestino de gerbils (Meriones unguiculatus infectados experimentalmente con quistes purificados a partir de muestras positivas de materia fecal humana. Para la estandarización y evaluación de la prueba, se emplearon 60 sueros de pacientes con giardiosis comprobada parasitológicamente (muestras positivas y 47 sueros de cordón umbilical recién cortado (muestras negativas. Como conjugado, se utilizó anti-lgG humana ligada a fosfatasa alcalina. La concentración óptima de antígeno de trofozoíto de G. duodenalis fue de 15 ug/ml y las diluciones óptimas de suero y conjugado fueron 1:25 y 1:400, respectivamente. El valor del punto de corte (absorbancia fue 0,300. Los parámetros de la prueba fueron: sensibilidad, 98,3% (intervalo de confianza de 95% (lC 95%: 89,9%-99,974; especificidad, 957% (IC 95%:84,3%-99,3%; valor predictivo positivo, 96,7% (IC 95%: 87,6%-99,4%, y valor predictivo negativo, 97,8% (IC 95%: 87,0%-99,9%. La prueba ELlSA descrita contribuirá a mejorar el diagnóstico de giardiosis y podrá ser empleada para estudios epidemiológicos de seroprevalencia.

  2. Ensaio terapêutico na infecção por Giardia muris em camundongo com metronidazole, tinidazole, secnidazole e furazolidone

    Directory of Open Access Journals (Sweden)

    Claudia Cristina Pedigone Cruz

    1997-06-01

    Full Text Available Foi testado in vivo a sensibilidade de Giardia muris a quatro drogas comumente usadas no tratamento da giardíase humana. Foram utilizados 7 grupos de animais, com 12 camundongos cada, sendo que o grupo controle recebeu apenas solução salina 0,15M (0,5ml/animal. Os demais grupos receberam em dose única: metronidazole e furazolidone (500mg/kg, tinidazole e secnidazole (200mg/kg. A eficácia das drogas foi avaliada através da contagem de cistos nas fezes e pela ausência de trofozoítos no intestino. O metronidazole foi a droga mais eficaz. Os cortes histológicos mostraram diferenças entre o padrão da mucosa intestinal de animais normais e parasitados. No entanto, não se observou diferença entre o padrão de mucosa de animais infectados tratados e não tratados, o que sugere que estas alterações podem ser causadas pelo parasito e não pelas drogas.A comparative study about the effectiveness of metronidazole, tinidazole, secnidazole and furazolidone was performed on Giardia muris from mice naturally infected. Groups of 12 animals each was constituted: the control treated with saline; one treated with metronidazole; one treated with furazolidone; one treated with tinidazole; one treated with secnidazole; histological normal control; histological infected. Samples of three stools were examined before and after treatment with quantification of cysts. Animals were cured when the trophozoites was not seen in the small bowel. The curative activity of drugs was 58.3% for metronidazole, 50% for furazolidone, 40% for secnidazole and 16% for tinidazole. It was also showed that there was a different pattern of the intestinal mucosa from the control and infected groups, treated or not, suggesting that the alterations encountered in the mucosa of infected animals were due to the parasitism either the action of the drugs.

  3. Symposium on Differential Geometry and Differential Equations

    CERN Document Server

    Berger, Marcel; Bryant, Robert

    1987-01-01

    The DD6 Symposium was, like its predecessors DD1 to DD5 both a research symposium and a summer seminar and concentrated on differential geometry. This volume contains a selection of the invited papers and some additional contributions. They cover recent advances and principal trends in current research in differential geometry.

  4. Automatic differentiation bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Corliss, G.F. [comp.

    1992-07-01

    This is a bibliography of work related to automatic differentiation. Automatic differentiation is a technique for the fast, accurate propagation of derivative values using the chain rule. It is neither symbolic nor numeric. Automatic differentiation is a fundamental tool for scientific computation, with applications in optimization, nonlinear equations, nonlinear least squares approximation, stiff ordinary differential equation, partial differential equations, continuation methods, and sensitivity analysis. This report is an updated version of the bibliography which originally appeared in Automatic Differentiation of Algorithms: Theory, Implementation, and Application.

  5. Genotyping of Giardia duodenalis in vegetables cultivated with organic and chemical fertilizer from street markets and community vegetable gardens in a region of Southern Brazil.

    Science.gov (United States)

    Rafael, Katyelle; Marchioro, Ariella A; Colli, Cristiane M; Tiyo, Bruna T; Evangelista, Fernanda F; Bezagio, Renata C; Falavigna-Guilherme, Ana L

    2017-12-01

    In order to investigate the occurrence of Giardia duodenalis and its genotypes in vegetables that are consumed raw, we analyzed samples cultivated with organic or chemical fertilizer, sold in street markets and from community vegetable gardens in an urban area located in Southern Brazil. We analyzed 130 samples of vegetables such as crisp lettuce, regular lettuce, kale, chicory and rocket, from street markets, and 130 from community gardens. From each sample, 50 g were washed in Tween 80 solution (1%) and the solution obtained was filtered through a cellulose acetate membrane. The retained material was used for DNA extraction with the commercial kit Purelink®. GDH gene was amplified by semi-nested PCR using the GDHeF, GDHiR and GDHiF primers. Positive samples were genotyped using the PCR-RFLP technique with the restriction enzyme NlaIV. We obtained 7.3% (19/260) positive samples for G. duodenalis, both from street markets (10/130) and from community gardens (9/130), including organic and non-organic products. The assemblage AI was predominant, but assemblages B and E were also found. The molecular technique revealed genotypes with zoonotic potential, evidencing the importance of investigating commercialized vegetables that are consumed raw and establishing a more rigid quality control.

  6. Seasonal prevalence and incidence of Cryptosporidium spp. and Giardia duodenalis and associated diarrhoea in children attending pre-schools in Kafue, Zambia

    DEFF Research Database (Denmark)

    Siwila, J.; Phiri, I.G.K.; Enemark, Heidi L.

    2011-01-01

    Prevalence, incidence and seasonal variation of Cryptosporidium and Giardia duodenalis were studied over a 12-month period in 100 children from four pre-schools in Kafue, Zambia. Questionnaire data and a single stool sample were collected monthly from each child. Samples were processed using...... a commercial kit (Meridian Diagnostics Inc., USA) and oo(cysts) visualised by immunofluorescence microscopy. Cryptosporidium was detected in 30.7% (241/786; 95% CI = 27.5-33.9) while G. duodenalis was detected in 29.0% (228/786; 95% CI = 25.8-32.2). A total of 86% experienced one or more episodes...... of cryptosporidiosis while 75% had giardiasis. Cumulative incidence per 100 children was 75.4 for Cryptosporidium and 49.0 for G. duodenalis. Both infections were significantly more common in the wet compared to the dry season (34.8%, 162/466 vs. 24.7%, 79/320, P = 0.003 and 35.2%, 164/466 vs. 20.0%, 64/320, P

  7. Giardia duodenalis in Captive Tigers (Panthera tigris, Palawan Bearcats (Arctictis binturong whitei and Asian Palm Civet (Paradoxurus hermaphroditus at a Wildlife Facility in Manila, Philippines

    Directory of Open Access Journals (Sweden)

    Nick Angelo P. VELANTE

    2017-09-01

    Full Text Available Background: This study was conducted to determine the prevalence of Giardia duodenalis in captive animals in a wildlife facility. This is the first study conducted in these animals from the facility.Methods: Eight captive tigers (Panthera tigris, two Palawan bearcats (Arctictis binturong whitei and one Asian Palm Civet (Paradoxurus hermaphroditus currently housed at a wildlife facility in Manila, Philippines were considered in 2012. These animals were apparently healthy with no signs of disease during the study. Sample collection was done twice at two months interval where freshly voided fecal samples were grossly examined, characterized and preserved in Sodium Acetate Formalin (SAF. The samples were used to determine the presence of G. duodenalis using modified flotation-sedimentation and commercially available immuno-chromatographic assay test kit.Results: All fecal samples tested were negative for the presence of G. duodenalis trophozoites, and cysts using the former. Furthermore, none of the samples tested positive for and G. duodenalis antigen using immune-chromatographic assay.Conclusion: There is no existing infection of G. duodenalis among captive tigers, Palawan Bearcats and Asian palm civet housed at the wildlife facility. 

  8. Interactions between the intestinal flagellates Giardia muris and Spironucleus muris and the blood parasites Babesia microti, Plasmodium yoelii and Plasmodium berghei in mice.

    Science.gov (United States)

    Brett, S J; Cox, F E

    1982-08-01

    In mice infected with the intestinal flagellates Giardia muris or Spironucleus muris, together with the blood parasites Babesia microti or Plasmodium yoelii, there is a temporary decrease of flagellate cyst output coincident with the peak of the blood parasite infections, followed by a rapid return to normal levels. This decrease in cyst output is correlated with decreased numbers of trophozoites in the small intestine. The effect on S. muris is more marked than that on G. muris. Neither blood parasites has any effect on the total duration of the flagellate infection and the flagellates do not affect the blood parasites. In mice infected with G. muris or S. muris and P. berghei there is also a decrease in cyst output but this is less apparent than in infections with B. microti or P. yoelii because of the fatal nature of the P. berghei infection. It is suggested that the decrease in cyst output is probably due to changes in the contents of the small intestine or to non-specific immunological factors rather than to specific immunological changes.

  9. Food handlers as a link in the chain of transmission of Giardia duodenalis and other protozoa in public schools in southern Brazil.

    Science.gov (United States)

    Colli, Cristiane Maria; Bezagio, Renata Coltro; Nishi, Letícia; Ferreira, Érika Cristina; Falavigna-Guilherme, Ana Lúcia; Gomes, Mônica Lúcia

    2015-09-01

    Food handlers (FHs) may facilitate transmission and dissemination of pathogens. The importance of FHs as a link in the epidemiological chain of transmission of Giardia duodenalis and other intestinal protozoa was assessed. Fecal and subungual material from 27 FHs were analyzed using parasitological methods. G. duodenalis was identified by direct immunofluorescence and genotyped by PCR-RFLP for the bg and gdh genes, and gdh was sequenced. At least one protozoan was detected in 30% (8/27) of the FHs and G. duodenalis (19%; 5/27) was the most common species. The AII and BIV genotypes were found in 20% (1/5) and 60% (3/5) of FHs infected with G. duodenalis, respectively. FHs can be involved in the chain of transmission of G. duodenalis and other protozoa. KJ741310 - KJ741313. © The Author 2015. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Partial Differential Equations

    CERN Document Server

    1988-01-01

    The volume contains a selection of papers presented at the 7th Symposium on differential geometry and differential equations (DD7) held at the Nankai Institute of Mathematics, Tianjin, China, in 1986. Most of the contributions are original research papers on topics including elliptic equations, hyperbolic equations, evolution equations, non-linear equations from differential geometry and mechanics, micro-local analysis.

  11. Solving Linear Differential Equations

    NARCIS (Netherlands)

    Nguyen, K.A.; Put, M. van der

    2010-01-01

    The theme of this paper is to 'solve' an absolutely irreducible differential module explicitly in terms of modules of lower dimension and finite extensions of the differential field K. Representations of semi-simple Lie algebras and differential Galo is theory are the main tools. The results extend

  12. Long-term monitoring of microsporidia, Cryptosporidium and Giardia infections in western Lowland Gorillas (Gorilla gorilla gorilla) at different stages of habituation in Dzanga Sangha Protected Areas, Central African Republic.

    Science.gov (United States)

    Sak, Bohumil; Petrzelkova, Klara J; Kvetonova, Dana; Mynarova, Anna; Shutt, Kathryn A; Pomajbikova, Katerina; Kalousova, Barbora; Modry, David; Benavides, Julio; Todd, Angelique; Kvac, Martin

    2013-01-01

    Infectious diseases pose one of the greatest threats to endangered species, and a risk of gastrointestinal parasite transmission from humans to wildlife has always been considered as a major concern of tourism. Increased anthropogenic impact on primate populations may result in general changes in communities of their parasites, and also in a direct exchange of parasites between humans and primates. To evaluate the impact of close contact with humans on the occurrence of potentially zoonotic protists in great apes, we conducted a long-term monitoring of microsporidia, Cryptosporidium and Giardia infections in western lowland gorillas at different stages of the habituation process, humans, and other wildlife in Dzanga-Sangha Protected Areas in the Central African Republic. We detected Encephalitozoon cuniculi genotypes I and II (7.5%), Enterocytozoon bieneusi genotype D and three novel genotypes (gorilla 1-3) (4.0%), Giardia intestinalis subgroup A II (2.0%) and Cryptosporidium bovis (0.5%) in gorillas, whereas in humans we found only G. intestinalis subgroup A II (2.1%). In other wild and domestic animals we recorded E. cuniculi genotypes I and II (2.1%), G. intestinalis assemblage E (0.5%) and C. muris TS03 (0.5%). Due to the non-specificity of E. cuniculi genotypes we conclude that detection of the exact source of E. cuniculi infection is problematic. As Giardia intestinalis was recorded primarily in gorilla groups with closer human contact, we suggest that human-gorilla transmission has occurred. We call attention to a potentially negative impact of habituation on selected pathogens which might occur as a result of the more frequent presence of humans in the vicinity of both gorillas under habituation and habituated gorillas, rather than as a consequence of the close contact with humans, which might be a more traditional assumption. We encourage to observe the sections concerning hygiene from the IUCN best practice guidelines for all sites where increased human

  13. African Journal of Biotechnology - Vol 12, No 9 (2013)

    African Journals Online (AJOL)

    Molecular identification of Giardia lamblia isolates from adult human cases in southwest of Iran · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. Elham Sadat Roointan, Abdollah Rafiei, Ali Reza Samarbaf-Zadeh, Ali Akbar Shayesteh, Ahmad Shamsizadeh, Mahdi ...

  14. 144__Olukosi_drinking wate

    African Journals Online (AJOL)

    User

    and Giardia lamblia; nutrients (fertilizers), dissolved metals and metalloids (lead, mercury, arsenic and so on) and dissolved organics (WHO, 2011). The demand for drinking water in Kaduna state is supplied by ground water sources such as wells and boreholes, tap water in areas where it is available, packaged water and ...

  15. Intestinal Parasites among Foreign Junior Staff of King Khalid ...

    African Journals Online (AJOL)

    Giardia lamblia and Entamoeba coli were the only protozoa identified. Those found positive ... Employers of this category of workers in food and vegetable industries, must ensure they are regularly screened and if found to be infected, promptly treated to interrupt transmission of these parasites to the community. Nigerian ...

  16. Author Details

    African Journals Online (AJOL)

    Onyido, AE. Vol 6, No 2 (2008) - Articles Arthropod-Associated Skin Diseases among Occupants of Five Designated Junior Staffs\\' Quarters in Owerri and Enugu, Nigeria Abstract · Vol 29, No 2 (2008) - Articles Prevalence of Giardia lamblia cyst; its detection in water bodies and relationship with environmental factors in ...

  17. Research concerning intestinal parasitosis in infant population discovered in two clinic laboratories from Oradea (Romania

    Directory of Open Access Journals (Sweden)

    Daniel-Dumitru PORTELECHI

    2006-05-01

    Full Text Available Considering the research made and the data offered by the specialists in parasitology from Oradea’s no.1 Polyclinic and Children’s Hospital, we have established that children from 1 to 18 years old have been found infected with 7 species of human parasites. Giardia lamblia, Blastocystis hominis, Ascaris lumbricoides, Oxyurus vermicularis, Trichurus trichiura, Hymenolepis nana, Hymenolepis diminuta.

  18. Protective Role of Commiphora molmol Extract against Liver and ...

    African Journals Online (AJOL)

    Tropical Journal of Pharmaceutical Research January 2016; 15 (1): 65-72 ... aminotransferase (AST), total bilirubin, urea, creatinine, cholesterol and triglycerides showed a ... rabbits and Giardia lamblia infection in rats [11]. ... [12], antigastric ulcer and cytoprotective effects ... temperature and humidity, fed with commercial.

  19. Protozoal enteric infections among expatriates in Bangladesh

    NARCIS (Netherlands)

    Speelman, P.; Ljungström, I.

    1986-01-01

    In order to study the prevalence, incidence, and symptoms of infections with Giardia lamblia and Entamoeba histolytica, we followed 251 expatriates in Bangladesh over a 1-year period. Microscopic examination of fecal specimens was performed upon enrollment, at 3-month intervals, and during episodes

  20. Fundamentals of differential beamforming

    CERN Document Server

    Benesty, Jacob; Pan, Chao

    2016-01-01

    This book provides a systematic study of the fundamental theory and methods of beamforming with differential microphone arrays (DMAs), or differential beamforming in short. It begins with a brief overview of differential beamforming and some popularly used DMA beampatterns such as the dipole, cardioid, hypercardioid, and supercardioid, before providing essential background knowledge on orthogonal functions and orthogonal polynomials, which form the basis of differential beamforming. From a physical perspective, a DMA of a given order is defined as an array that measures the differential acoustic pressure field of that order; such an array has a beampattern in the form of a polynomial whose degree is equal to the DMA order. Therefore, the fundamental and core problem of differential beamforming boils down to the design of beampatterns with orthogonal polynomials. But certain constraints also have to be considered so that the resulting beamformer does not seriously amplify the sensors’ self noise and the mism...

  1. No molecular epidemiological evidence supporting household transmission of zoonotic Giardia duodenalis and Cryptosporidium spp. from pet dogs and cats in the province of Álava, Northern Spain.

    Science.gov (United States)

    de Lucio, Aida; Bailo, Begoña; Aguilera, María; Cardona, Guillermo A; Fernández-Crespo, Juan C; Carmena, David

    2017-06-01

    The role of pet dogs and cats as suitable source of human infections by the diarrheagenic protozoan parasites Giardia duodenalis and Cryptosporidium spp. has been a topic of intense debate for long time and still remains a largely unsolved problem. In this cross-sectional molecular epidemiological survey we attempted to investigate whether zoonotic (or zooanthroponotic) disease transmission was occurring among humans and domestic dogs and cats sharing the same spatial and temporal setting in both rural and urban areas of the province of Álava, Northern Spain. A total of 268 (including 179 human, 55 canine, and 34 feline) individual faecal specimens were obtained from 63 family households during February-March and November-December 2014. Detection of G. duodenalis cysts and Cryptosporidium spp. oocysts was achieved by direct fluorescence microscopy (DFAT) and PCR-based methods targeting the small subunit (SSU) ribosomal RNA gene of the parasites. Giardia-positive isolates were subsequently sub-genotyped at the glutamate dehydrogenase (GDH) and β-giardin (BG) genes. Overall, G. duodenalis infections were identified in 3.4% (6/179) of humans, 29% (16/55) of dogs, and 5.9% (2/34) of cats, respectively. Cryptosporidium spp. infections were detected in 1.1% (2/179) of humans, 5.5% (3/55) of dogs, and 8.8% (3/34) of cats, respectively. Simultaneous infections in human and canine/feline hosts by G. duodenalis or Cryptosporidium spp. were only demonstrated in a single household in which a cat and its owner tested positive for Cryptosporidium by DFAT, but this result could not be confirmed by SSU-PCR. Infections were homogeneously distributed among the studied human or animal populations irrespectively of their sex, age group, or geographical region of origin. Inadequate washing of raw vegetables and fruits was the only risk factor significantly associated to a higher likelihood of having human giardiosis/cryptosporidiosis. Molecular characterization of G. duodenalis

  2. Vector Differential Calculus

    OpenAIRE

    HITZER, Eckhard MS

    2002-01-01

    This paper treats the fundamentals of the vector differential calculus part of universal geometric calculus. Geometric calculus simplifies and unifies the structure and notation of mathematics for all of science and engineering, and for technological applications. In order to make the treatment self-contained, I first compile all important geometric algebra relationships,which are necesssary for vector differential calculus. Then differentiation by vectors is introduced and a host of major ve...

  3. Differential models in ecology

    International Nuclear Information System (INIS)

    Barco Gomez, Carlos; Barco Gomez, German

    2002-01-01

    The models mathematical writings with differential equations are used to describe the populational behavior through the time of the animal species. These models can be lineal or no lineal. The differential models for unique specie include the exponential pattern of Malthus and the logistical pattern of Verlhust. The lineal differential models to describe the interaction between two species include the competition relationships, predation and symbiosis

  4. Evaluation of multiplex tandem real-time PCR for detection of Cryptosporidium spp., Dientamoeba fragilis, Entamoeba histolytica, and Giardia intestinalis in clinical stool samples.

    Science.gov (United States)

    Stark, D; Al-Qassab, S E; Barratt, J L N; Stanley, K; Roberts, T; Marriott, D; Harkness, J; Ellis, J T

    2011-01-01

    The aim of this study was to describe the first development and evaluation of a multiplex tandem PCR (MT-PCR) assay for the detection and identification of 4 common pathogenic protozoan parasites, Cryptosporidium spp., Dientamoeba fragilis, Entamoeba histolytica, and Giardia intestinalis, from human clinical samples. A total of 472 fecal samples submitted to the Department of Microbiology at St. Vincent's Hospital were included in the study. The MT-PCR assay was compared to four real-time PCR (RT-PCR) assays and microscopy by a traditional modified iron hematoxylin stain. The MT-PCR detected 28 G. intestinalis, 26 D. fragilis, 11 E. histolytica, and 9 Cryptosporidium sp. isolates. Detection and identification of the fecal protozoa by MT-PCR demonstrated 100% correlation with the RT-PCR results, and compared to RT-PCR, MT-PCR exhibited 100% sensitivity and specificity, while traditional microscopy of stained fixed fecal smears exhibited sensitivities and specificities of 56% and 100% for Cryptosporidium spp., 38% and 99% for D. fragilis, 47% and 97% for E. histolytica, and 50% and 100% for G. intestinalis. No cross-reactivity was detected in 100 stool samples containing various other bacterial, viral, and protozoan species. The MT-PCR assay was able to provide rapid, sensitive, and specific simultaneous detection and identification of the four most important diarrhea-causing protozoan parasites that infect humans. This study also highlights the lack of sensitivity demonstrated by microscopy, and thus, molecular methods such as MT-PCR must be considered the diagnostic methods of choice for enteric protozoan parasites.

  5. Evaluation of the Roche LightMix Gastro parasites multiplex PCR assay detecting Giardia duodenalis, Entamoeba histolytica, cryptosporidia, Dientamoeba fragilis, and Blastocystis hominis.

    Science.gov (United States)

    Friesen, J; Fuhrmann, J; Kietzmann, H; Tannich, E; Müller, M; Ignatius, R

    2018-03-23

    Multiplex PCR assays offer highly sensitive and specific tools for the detection of enteric pathogens. This prospective study aimed at comparing the novel Roche LightMix Modular Assay Gastro Parasites (LMAGP) detecting Giardia duodenalis, Entamoeba histolytica, Cryptosporidium spp., Blastocystishominis, and Dientamoebafragilis with routine laboratory procedures. Stool specimens (n = 1062 from 1009 patients) were consecutively examined by LMAGP, R-Biopharm Ridascreen enzyme immunoassays (EIAs) detecting G. duodenalis or E. histolytica/dispar, and microscopy of wet mounts. Discrepant results were analysed by in-house PCR. D. fragilis or B. hominis were detected by LMAGP in 131 (14.4%) and 179 (19.9%; 16 samples positive by microscopy; p PCR). G. duodenalis was detected by LMAGP, EIA, or microscopy in 20, 16, or 9 of 1039 stool samples, respectively; all four samples missed by EIA were confirmed by in-house PCR. In total, 938 stool samples were analysed for E. histolytica/dispar. Nine of ten EIA-positive samples were negative by LMAGP but positive by in-house PCR for E. dispar. One E. histolytica infection (positive by both LMAGP and in-house PCR) was missed by EIA and microscopy. Parasites only detected by microscopy included Enterobius vermicularis eggs (n = 3) and apathogenic amoebae (n = 27). The data call for routine use of multiplex PCR assays for the detection of enteric protozoan parasites in laboratory diagnostics. Copyright © 2018 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  6. Occurrence and molecular characterization of Giardia duodenalis and Cryptosporidium spp. in sheep and goats reared under dairy husbandry systems in Greece☆

    Science.gov (United States)

    Tzanidakis, Nikolaos; Sotiraki, Smaragda; Claerebout, Edwin; Ehsan, Amimul; Voutzourakis, Nikolaos; Kostopoulou, Despoina; Stijn, Casaert; Vercruysse, Jozef; Geurden, Thomas

    2014-01-01

    Giardia duodenalis and Cryptosporidium spp. are gastro-intestinal protozoa known to infect small ruminants. Both protozoa are also considered as a potential public health concern. The objective of this study was to determine their prevalence in lambs and goat kids kept under common Mediterranean dairy husbandry systems and to identify the species and genotypes infecting these small ruminants. In total, 684 faecal samples (429 from lambs and 255 from goat kids) were collected on 21 farms in Greece and examined using a quantitative immunofluorescence assay. G. duodenalis was detected in 37.3% of the lambs and 40.4% of the goat kids. On all but one of the farms G. duodenalis was detected. Most samples were typed as a mono-infection with G. duodenalis assemblage E, both on the β-giardin gene and the triose phosphate isomerase gene. Only 10% of samples were typed as mixed assemblage A and E infections. The prevalence of Cryptosporidium spp. was 5.1% in lambs and 7.1% in goat kids. In total, 8 out of the 14 farms with a sheep flock and 7 out of the 14 farms with a goat flock were positive. Cryptosporidium parvum (subtype IId), C. ubiquitum and C. xiaoi were identified, the latter especially in goat kids. In conclusion, the results of the present study illustrate that G. duodenalis and Cryptosporidium spp. occur frequently on both sheep and goats farms. The prevalence of zoonotic genotypes or species was low, indicating a limited but existing risk for zoonotic infections. PMID:25187088

  7. Chronic Giardia muris infection in anti-IgM-treated mice. I. Analysis of immunoglobulin and parasite-specific antibody in normal and immunoglobulin-deficient animals.

    Science.gov (United States)

    Snider, D P; Gordon, J; McDermott, M R; Underdown, B J

    1985-06-01

    To investigate the role of B cells and antibody in the immune response of mice to the murine intestinal parasite Giardia muris, we used mice treated from birth with rabbit anti-IgM antisera (aIgM). Such mice developed in serum and in gut secretions extreme Ig deficiency (IgM, IgA, and IgG) relative to control animals. The aIgM-treated mice showed no anti-G. muris antibody in serum or in gut wash material. Infections of G. muris in these mice were chronic, with a high load of parasite present in the small bowel, as reflected by prolonged cyst excretion (greater than 11 wk) and high trophozoite counts. In contrast, normal, untreated mice or NRS-treated animals developed anti-parasite IgA and IgG antibody in serum, demonstrated IgA antibody against the parasite in gut washings, and expelled the parasite within 9 wk. These effects of aIgM treatment on the murine response to primary infection with G. muris were demonstrated in two strains of mice: BALB/c and (C57BL/6 X C3H/He) F1. It was also observed that the response to G. muris infection in untreated animals was characterized by higher than normal total secretion of IgA into the gut and a concomitant increase in the serum polymeric IgA level. Mice treated with aIgM had a marked decrease of both monomeric and polymeric IgA in serum, and little detectable IgA in the intestinal lumen. These experiments provide the first demonstration that anti-IgM treatment suppresses a specific intestinal antibody response to antigen, and provide evidence that B cells and antibody play a role in the development of an effective response to a primary infection with G. muris in mice.

  8. Giardia telomeric sequence d(TAGGG)4 forms two intramolecular G-quadruplexes in K+ solution: effect of loop length and sequence on the folding topology.

    Science.gov (United States)

    Hu, Lanying; Lim, Kah Wai; Bouaziz, Serge; Phan, Anh Tuân

    2009-11-25

    Recently, it has been shown that in K(+) solution the human telomeric sequence d[TAGGG(TTAGGG)(3)] forms a (3 + 1) intramolecular G-quadruplex, while the Bombyx mori telomeric sequence d[TAGG(TTAGG)(3)], which differs from the human counterpart only by one G deletion in each repeat, forms a chair-type intramolecular G-quadruplex, indicating an effect of G-tract length on the folding topology of G-quadruplexes. To explore the effect of loop length and sequence on the folding topology of G-quadruplexes, here we examine the structure of the four-repeat Giardia telomeric sequence d[TAGGG(TAGGG)(3)], which differs from the human counterpart only by one T deletion within the non-G linker in each repeat. We show by NMR that this sequence forms two different intramolecular G-quadruplexes in K(+) solution. The first one is a novel basket-type antiparallel-stranded G-quadruplex containing two G-tetrads, a G x (A-G) triad, and two A x T base pairs; the three loops are consecutively edgewise-diagonal-edgewise. The second one is a propeller-type parallel-stranded G-quadruplex involving three G-tetrads; the three loops are all double-chain-reversal. Recurrence of several structural elements in the observed structures suggests a "cut and paste" principle for the design and prediction of G-quadruplex topologies, for which different elements could be extracted from one G-quadruplex and inserted into another.

  9. Genetic analysis of the Gdh and Bg genes of animal-derived Giardia duodenalis isolates in Northeastern China and evaluation of zoonotic transmission potential.

    Directory of Open Access Journals (Sweden)

    Aiqin Liu

    Full Text Available BACKGROUND: Giardia duodenalis is a common intestinal parasite that infects humans and many other mammals, mainly distributing in some areas with poor sanitation. The proportion of the human giardiasis burden attributable to G. duodenalis of animal origin differs in different geographical areas. In Mainland China, genetic data of the gdh and bg genes of G. duodenalis from animals are only limited in dogs and cats. The aim of the study was to provide information on the genetic characterizations of animal-derived G. duodenalis isolates (from rabbits, sheep and cattle at both loci in Heilongjiang Province, Northeastern China, and to assess the potential for zoonotic transmission. METHODOLOGY/PRINCIPAL FINDINGS: 61 G. duodenalis isolates from animal feces (dairy and beef cattle, sheep and rabbits in Heilongjiang Province were characterized at the gdh and bg loci in the present study. The gdh and bg gene sequences of sheep-derived G. duodenalis assemblage AI, and the gdh sequences of rabbit-derived G. duodenalis assemblage B had 100% similarity with those from humans, respectively. Novel subtypes of G. duodenalis were identified, with one and seven subtypes for assemblages A and E at the gdh locus, and two and three subtypes for assemblages B and E at the bg locus, respectively. Three pairs of the same bg sequences of assemblage E were observed in sheep and cattle. CONCLUSIONS/SIGNIFICANCE: This is the first description of genetic characterizations of the gdh and bg genes of G. duodenalis from rabbits, sheep and cattle in Mainland China. Homology analysis of assemblages AI and B implied the possibility of zoonotic transmission. The novel subtypes of assemblages of G. duodenalis may represent the endemic genetic characteristics of G. duodenalis in Heilongjiang Province, China.

  10. Singular stochastic differential equations

    CERN Document Server

    Cherny, Alexander S

    2005-01-01

    The authors introduce, in this research monograph on stochastic differential equations, a class of points termed isolated singular points. Stochastic differential equations possessing such points (called singular stochastic differential equations here) arise often in theory and in applications. However, known conditions for the existence and uniqueness of a solution typically fail for such equations. The book concentrates on the study of the existence, the uniqueness, and, what is most important, on the qualitative behaviour of solutions of singular stochastic differential equations. This is done by providing a qualitative classification of isolated singular points, into 48 possible types.

  11. Introduction to differentiable manifolds

    CERN Document Server

    Auslander, Louis

    2009-01-01

    The first book to treat manifold theory at an introductory level, this text surveys basic concepts in the modern approach to differential geometry. The first six chapters define and illustrate differentiable manifolds, and the final four chapters investigate the roles of differential structures in a variety of situations.Starting with an introduction to differentiable manifolds and their tangent spaces, the text examines Euclidean spaces, their submanifolds, and abstract manifolds. Succeeding chapters explore the tangent bundle and vector fields and discuss their association with ordinary diff

  12. Poorly Differentiated Thyroid Carcinoma.

    Science.gov (United States)

    Setia, Namrata; Barletta, Justine A

    2014-12-01

    Poorly differentiated thyroid carcinoma (PDTC) has been recognized for the past 30 years as an entity showing intermediate differentiation and clinical behavior between well-differentiated thyroid carcinomas (ie, papillary thyroid carcinoma and follicular thyroid carcinoma) and anaplastic thyroid carcinoma; however, there has been considerable controversy around the definition of PDTC. In this review, the evolution in the definition of PDTC, current diagnostic criteria, differential diagnoses, potentially helpful immunohistochemical studies, and molecular alterations are discussed with the aim of highlighting where the diagnosis of PDTC currently stands. Published by Elsevier Inc.

  13. Skew differential fields, differential and difference equations

    NARCIS (Netherlands)

    van der Put, M

    2004-01-01

    The central question is: Let a differential or difference equation over a field K be isomorphic to all its Galois twists w.r.t. the group Gal(K/k). Does the equation descend to k? For a number of categories of equations an answer is given.

  14. Osteoblastic cells: differentiation and trans-differentiation

    DEFF Research Database (Denmark)

    Kassem, Moustapha; Abdallah, Basem; Saeed, Hamid

    2008-01-01

    The osteoblast is the bone forming cell and is derived from mesenchymal stem cells (MSC) present among the bone marrow stroma. MSC are capable of multi-lineage differentiation into mesoderm-type cells such as osteoblasts and adipocytes. Understanding the mechanisms underlying osteoblast different...

  15. Occurrence of enteroparasites in day care centers in Botucatu (São Paulo State, Brazil with emphasis on Cryptosporidium sp., Giardia duodenalis and Enterobius vermicularis Ocorrência de enteroparasitas em creches de Botucatu (Estado de São Paulo, Brasil com ênfase em Cryptosporidium sp., Giardia duodenalis e Enterobius vermicularis

    Directory of Open Access Journals (Sweden)

    Thaís Batista de Carvalho

    2006-10-01

    Full Text Available The occurrence of the enteroparasites was verified in 279 children (0 to 6 years of four municipal day cares of Botucatu/SP. Three samples of each child's feces were collected and processed by the methods of Hoffman-Pons-Janner, Faust and Ritchie and subsequent coloration of the fecal smear by the methods of Auramina-O and Ziehl-Neelsen modified for diagnosis of Cryptosporidium sp. and Graham method for diagnosis of Enterobius vermicularis. Of the analyzed children we verified a prevalence of intestinal parasitism in 53.40%, and the most frequent parasite was Giardia duodenalis (26.88%. Significant association was verified among enteroparasitosis, family income, maternal education and age; the lowest enteroparasite frequency occurred in children of families with larger income and higher education. It was observed that G. duodenalis is more prevalent in children from 0 to 4 years and E. vermicularis is more frequent in children between three and four years old. The high enteroparasite prevalence in day cares suggests complex structure in its epidemiology, where factors beyond sanitation should be considered.Verificou-se a prevalência dos enteroparasitas em 279 crianças (0 a 6 anos de quatro creches municipais de Botucatu/SP. Foram coletadas três amostras de fezes de cada criança e processadas pelos métodos Hoffman, Faust e Ritchie e posterior coloração do esfregaço fecal pelos métodos de Auramina-O e Ziehl-Neelsen modificado para diagnóstico de Cryptosporidium sp. e método da fita gomada para diagnóstico de Enterobius vermicularis. Das crianças analisadas apresentaram-se parasitadas 53.40%, sendo que o parasita mais freqüente foi Giardia duodenalis (26.88%. Verificou-se associação significativa entre enteroparasitose, renda familiar, escolaridade materna e idade; quanto maior a renda e o grau escolar, menor a freqüência de enteroparasitas. Observou-se que G. duodenalis é mais prevalente em crianças de 0 a 4 anos e E

  16. Lifting the Differentiation Embargo.

    Science.gov (United States)

    Latif, Anne-Louise; Holyoake, Tessa L

    2016-09-22

    Effective differentiation therapy for acute myeloid leukemia (AML) has been restricted to a small subset of patients with one defined genetic abnormality. Using an unbiased small molecule screen, Sykes et al. now identify a mechanism of de-repression of differentiation in several models of AML driven by distinct genetic drivers. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Lifting the differentiation embargo

    OpenAIRE

    Latif, Anne-Louise; Holyoake, Tessa

    2016-01-01

    Effective differentiation therapy for acute myeloid leukemia (AML) has been restricted to a small subset of patients with one defined genetic abnormality. Using an unbiased small molecule screen, Sykes et al. now identify a mechanism of de-repression of differentiation in several models of AML driven by distinct genetic drivers.

  18. Calculus & ordinary differential equations

    CERN Document Server

    Pearson, David

    1995-01-01

    Professor Pearson's book starts with an introduction to the area and an explanation of the most commonly used functions. It then moves on through differentiation, special functions, derivatives, integrals and onto full differential equations. As with other books in the series the emphasis is on using worked examples and tutorial-based problem solving to gain the confidence of students.

  19. Nonlinear differential equations

    Energy Technology Data Exchange (ETDEWEB)

    Dresner, L.

    1988-01-01

    This report is the text of a graduate course on nonlinear differential equations given by the author at the University of Wisconsin-Madison during the summer of 1987. The topics covered are: direction fields of first-order differential equations; the Lie (group) theory of ordinary differential equations; similarity solutions of second-order partial differential equations; maximum principles and differential inequalities; monotone operators and iteration; complementary variational principles; and stability of numerical methods. The report should be of interest to graduate students, faculty, and practicing scientists and engineers. No prior knowledge is required beyond a good working knowledge of the calculus. The emphasis is on practical results. Most of the illustrative examples are taken from the fields of nonlinear diffusion, heat and mass transfer, applied superconductivity, and helium cryogenics.

  20. Differential equations for dummies

    CERN Document Server

    Holzner, Steven

    2008-01-01

    The fun and easy way to understand and solve complex equations Many of the fundamental laws of physics, chemistry, biology, and economics can be formulated as differential equations. This plain-English guide explores the many applications of this mathematical tool and shows how differential equations can help us understand the world around us. Differential Equations For Dummies is the perfect companion for a college differential equations course and is an ideal supplemental resource for other calculus classes as well as science and engineering courses. It offers step-by-step techniques, practical tips, numerous exercises, and clear, concise examples to help readers improve their differential equation-solving skills and boost their test scores.

  1. Nonlinear differential equations

    International Nuclear Information System (INIS)

    Dresner, L.

    1988-01-01

    This report is the text of a graduate course on nonlinear differential equations given by the author at the University of Wisconsin-Madison during the summer of 1987. The topics covered are: direction fields of first-order differential equations; the Lie (group) theory of ordinary differential equations; similarity solutions of second-order partial differential equations; maximum principles and differential inequalities; monotone operators and iteration; complementary variational principles; and stability of numerical methods. The report should be of interest to graduate students, faculty, and practicing scientists and engineers. No prior knowledge is required beyond a good working knowledge of the calculus. The emphasis is on practical results. Most of the illustrative examples are taken from the fields of nonlinear diffusion, heat and mass transfer, applied superconductivity, and helium cryogenics

  2. Linking Diversity and Differentiation

    Directory of Open Access Journals (Sweden)

    Hans-Rolf Gregorius

    2010-03-01

    Full Text Available Generally speaking, the term differentiation refers to differences between collections for the distribution of specified traits of their members, while diversity deals with (effective numbers of trait states (types. Counting numbers of types implies discrete traits such as alleles and genotypes in population genetics or species and taxa in ecology. Comparisons between the concepts of differentiation and diversity therefore primarily refer to discrete traits. Diversity is related to differentiation through the idea that the total diversity of a subdivided collection should be composed of the diversity within the subcollections and a complement called “diversity between subcollections”. The idea goes back to the perception that the mixing of differentiated collections increases diversity. Several existing concepts of “diversity between subcollections” are based on this idea. Among them, β-diversity and fixation (inadvertently called differentiation are the most prominent in ecology and in population genetics, respectively. The pertaining measures are shown to quantify the effect of differentiation in terms of diversity components, though from a dual perspective: the classical perspective of differentiation between collections for their type compositions, and the reverse perspective of differentiation between types for their collection affiliations. A series of measures of diversity-oriented differentiation is presented that consider this dual perspective at two levels of diversity partitioning: the overall type or subcollection diversity and the joint type-subcollection diversity. It turns out that, in contrast with common notions, the measures of fixation (such as FST or GST refer to the perspective of type rather than subcollection differentiation. This unexpected observation strongly suggests that the popular interpretations of fixation measures must be reconsidered.

  3. Van Bölge Eğitim ve Araştırma Hastanesi\\'nde Giardia intestinalis ve Entamoeba histolytica/dispar prevalansı: Dört yıllık izlem

    OpenAIRE

    Bayram, Yasemin; Parlak, Mehmet; Çıkman, Aytekin

    2013-01-01

    Amaç: Çalışmada dört yıllık sürede Giardia intestinalis ve Entemoeba histolytica/ Entemoeba dispar saptanma oranı, yıllar göre dağılımı ile yaş grupları ve cinsiyete göre dağılımının retrospektif olarak belirlenmesi amaçlanmış­tır. Gereç ve yöntem: Ocak 2008 ile Aralık 2011 tarihleri arasında laboratuvarımıza gönderilen 9911 dışkı örneği parazitolojik yönden incelenmiştir. Taze dışkı örneklerinde Entamoeba sp., Giardia trofozoit ve kistlerinin mikrosko­bik teşhisi i...

  4. Hyperbolic partial differential equations

    CERN Document Server

    Witten, Matthew

    1986-01-01

    Hyperbolic Partial Differential Equations III is a refereed journal issue that explores the applications, theory, and/or applied methods related to hyperbolic partial differential equations, or problems arising out of hyperbolic partial differential equations, in any area of research. This journal issue is interested in all types of articles in terms of review, mini-monograph, standard study, or short communication. Some studies presented in this journal include discretization of ideal fluid dynamics in the Eulerian representation; a Riemann problem in gas dynamics with bifurcation; periodic M

  5. Differential equations problem solver

    CERN Document Server

    Arterburn, David R

    2012-01-01

    REA's Problem Solvers is a series of useful, practical, and informative study guides. Each title in the series is complete step-by-step solution guide. The Differential Equations Problem Solver enables students to solve difficult problems by showing them step-by-step solutions to Differential Equations problems. The Problem Solvers cover material ranging from the elementary to the advanced and make excellent review books and textbook companions. They're perfect for undergraduate and graduate studies.The Differential Equations Problem Solver is the perfect resource for any class, any exam, and

  6. Differential Equations as Actions

    DEFF Research Database (Denmark)

    Ronkko, Mauno; Ravn, Anders P.

    1997-01-01

    We extend a conventional action system with a primitive action consisting of a differential equation and an evolution invariant. The semantics is given by a predicate transformer. The weakest liberal precondition is chosen, because it is not always desirable that steps corresponding to differential...... actions shall terminate. It is shown that the proposed differential action has a semantics which corresponds to a discrete approximation when the discrete step size goes to zero. The extension gives action systems the power to model real-time clocks and continuous evolutions within hybrid systems....

  7. Beginning partial differential equations

    CERN Document Server

    O'Neil, Peter V

    2011-01-01

    A rigorous, yet accessible, introduction to partial differential equations-updated in a valuable new edition Beginning Partial Differential Equations, Second Edition provides a comprehensive introduction to partial differential equations (PDEs) with a special focus on the significance of characteristics, solutions by Fourier series, integrals and transforms, properties and physical interpretations of solutions, and a transition to the modern function space approach to PDEs. With its breadth of coverage, this new edition continues to present a broad introduction to the field, while also addres

  8. Ordinary differential equations

    CERN Document Server

    Miller, Richard K

    1982-01-01

    Ordinary Differential Equations is an outgrowth of courses taught for a number of years at Iowa State University in the mathematics and the electrical engineering departments. It is intended as a text for a first graduate course in differential equations for students in mathematics, engineering, and the sciences. Although differential equations is an old, traditional, and well-established subject, the diverse backgrounds and interests of the students in a typical modern-day course cause problems in the selection and method of presentation of material. In order to compensate for this diversity,

  9. Uncertain differential equations

    CERN Document Server

    Yao, Kai

    2016-01-01

    This book introduces readers to the basic concepts of and latest findings in the area of differential equations with uncertain factors. It covers the analytic method and numerical method for solving uncertain differential equations, as well as their applications in the field of finance. Furthermore, the book provides a number of new potential research directions for uncertain differential equation. It will be of interest to researchers, engineers and students in the fields of mathematics, information science, operations research, industrial engineering, computer science, artificial intelligence, automation, economics, and management science.

  10. Problems in differential equations

    CERN Document Server

    Brenner, J L

    2013-01-01

    More than 900 problems and answers explore applications of differential equations to vibrations, electrical engineering, mechanics, and physics. Problem types include both routine and nonroutine, and stars indicate advanced problems. 1963 edition.

  11. Criticality in cell differentiation

    Indian Academy of Sciences (India)

    Indrani Bose

    2017-11-09

    Nov 9, 2017 ... Differentiation is mostly based on binary decisions with the progenitor cells ..... accounts for the dominant part of the remaining variation ... significant loss in information. ..... making in vitro: emerging concepts and novel tools.

  12. Differentiation of subdural effusions

    International Nuclear Information System (INIS)

    Wetterling, T.; Rama, B.

    1989-01-01

    Although X-ray computerized tomography facilitates the diagnosis of intracranial disorders, differentiation of the lesions like extracerebral effusions is often unsatisfactory. Epidural and acute subdural haematoma shown as hyperdensity in CT requires an emergency neurosurgical operation, so that differentiation of these hyperdense effusions may not be required. But the discrimination of the effusions shown as hypodensity in CT (chronic subdural haematoma, subdural hygroma, subdural empyema as well as arachnoid cysts) is urgent because of the different treatment of these effusions. The clinical differentiation is hampered by unspecific neurologic symptoms and the lack of adequate laboratory tests. Some aspects facilitating the diagnostic decision are presented. Recent magnetic resonance (MR) studies promise further progress in differentiating between subdural effusions. (orig.) [de

  13. Cryptosporidium spp., Giardia duodenalis, Enterocytozoon bieneusi and other intestinal parasites in young children in Lobata province, Democratic Republic of São Tomé and Principe.

    Directory of Open Access Journals (Sweden)

    Maria Luísa Lobo

    Full Text Available Rare systemic studies concerning prevalence of intestinal parasites in children have been conducted in the second smallest country in Africa, the Democratic Republic of São Tomé and Príncipe. Fecal specimens from 348 children (214 in-hospital attending the Aires de Menezes Hospital and 134 from Agostinho Neto village in São Tome Island were studied by parasitological and molecular methods. Of the 134 children from Agostinho Neto, 52.2% presented intestinal parasites. 32.1% and 20.2% of these children had monoparasitism and polyparasitism, respectively. Ascaris lumbricoides (27.6%, G. duodenalis (7.5%, T. trichiura (4.5% and Entamoeba coli (10.5% were the more frequent species identified in the children of this village. Giardia duodenalis (7.5% and E. bieneusi (5.2% were identified by PCR. Nested-PCR targeting G. duodenalis TPI identified Assemblage A (60% and Assemblage B (40%. The E. bieneusi ITS-based sequence identified genotypes K (57.1%, KIN1 (28.6% and KIN3 (14.3%. Among the 214 in-hospital children, 29.4% presented intestinal parasites. In 22.4% and 7.0% of the parasitized children, respectively, one or more species were concurrently detected. By microscopy, A. lumbricoides (10.3% and Trichiuris trichiura (6.5% were the most prevalent species among these children, and Cryptosporidium was detected by PCR in 8.9% of children. GP60 locus analysis identified 6.5% of C. hominis (subtypes IaA27R3 [35.7%], IaA23R3 [14.3%], IeA11G3T3 [28.6%] and IeA11G3T3R1 [21.4%] and 2.3% of C. parvum (subtypes IIaA16G2R1 [20.0%], IIaA15G2R1 [20.0%], IIdA26G1 [40.0%] and IIdA21G1a [20.0%]. G. duodenalis and E. bieneusi were identified in 0.5% and 8.9% of the in-hospital children, respectively. G. duodenalis Assemblage B was characterized. The E. bieneusi genotypes K (52.6%, D (26.4%, A (10.5% and KIN1 (10.5% were identified. Although further studies are required to clarify the epidemiology of these infectious diseases in this endemic region the significance

  14. Prevalence and Genetic Diversity of Giardia duodenalis and Cryptosporidium spp. among School Children in a Rural Area of the Amhara Region, North-West Ethiopia.

    Directory of Open Access Journals (Sweden)

    Aida de Lucio

    Full Text Available Giardia duodenalis and Cryptosporidium spp. are enteric protozoan causing gastrointestinal illness in humans and animals. Giardiasis and cryptosporidiosis are not formally considered as neglected tropical diseases, but belong to the group of poverty-related infectious diseases that impair the development and socio-economic potential of infected individuals in developing countries.We report here the prevalence and genetic diversity of G. duodenalis and Cryptosporidium spp. in children attending rural primary schools in the Bahir Dar district of the Amhara Region, Ethiopia. Stool samples were collected from 393 children and analysed by molecular methods. G. duodenalis was detected by real-time PCR, and the assemblages and sub-assemblages were determined by multilocus sequence-based genotyping of the glutamate dehydrogenase and β-giardin genes of the parasite. Detection and identification of Cryptosporidium species was carried out by sequencing of a partial fragment of the small-subunit ribosomal RNA gene.The PCR-based prevalences of G. duodenalis and Cryptosporidium spp. were 55.0% (216/393 and 4.6% (18/393, respectively. A total of 78 G. duodenalis isolates were successfully characterized, revealing the presence of sub-assemblages AII (10.3%, BIII (28.2%, and BIV (32.0%. Discordant typing results AII/AIII and BIII/BIV were identified in 7.7% and 15.4% of the isolates, respectively. An additional five (6.4% isolates were assigned to assemblage B. No mixed infections of assemblages A+B were found. Extensive genetic variation at the nucleotide level was observed within assemblage B (but no within assemblage A, resulting in the identification of a large number of sub-types. Cryptosporidium diversity was demonstrated by the occurrence of C. hominis, C. parvum, and C. viatorum in the population under study.Our data suggest an epidemiological scenario with an elevated transmission intensity of a wide range of G. duodenalis genetic variants. Importantly

  15. On paragrassmann differential calculus

    International Nuclear Information System (INIS)

    Filippov, A.T.; Isaev, A.P.; Kurdikov, A.B.

    1992-01-01

    The paper significantly extends and generalizes our previous paper. Here we discuss explicit general constructions for paragrassmann calculus with one and many variables. For one variable nondegenerate differentiation algebras are identified and shown to be equivalent to the algebra of (p+1)x(p+1) complex matrices. For many variables we give a general construction of the differentiation algebras. Some particular examples are related to the multiparametric quantum deformations of the harmonic oscillators. 18 refs

  16. Differential forms of supermanifolds

    International Nuclear Information System (INIS)

    Beresin, P.A.

    1979-01-01

    The theory of differential and pseUdo-differential forms on supermanifolds is constructed. The definition and notations of superanalogy of the Pontryagin and Chern characteristic classes are given. The theory considered is purely local. The scheme suggested here generalizes the so-called Weil homomorphism for superspace which lays on the basis of the Chern and Potryagin characteristic class theory. The theory can be extended to the global supermanifolds

  17. Solving Ordinary Differential Equations

    Science.gov (United States)

    Krogh, F. T.

    1987-01-01

    Initial-value ordinary differential equation solution via variable order Adams method (SIVA/DIVA) package is collection of subroutines for solution of nonstiff ordinary differential equations. There are versions for single-precision and double-precision arithmetic. Requires fewer evaluations of derivatives than other variable-order Adams predictor/ corrector methods. Option for direct integration of second-order equations makes integration of trajectory problems significantly more efficient. Written in FORTRAN 77.

  18. Ordinary differential equations

    CERN Document Server

    Greenberg, Michael D

    2014-01-01

    Features a balance between theory, proofs, and examples and provides applications across diverse fields of study Ordinary Differential Equations presents a thorough discussion of first-order differential equations and progresses to equations of higher order. The book transitions smoothly from first-order to higher-order equations, allowing readers to develop a complete understanding of the related theory. Featuring diverse and interesting applications from engineering, bioengineering, ecology, and biology, the book anticipates potential difficulties in understanding the various solution steps

  19. Beginning partial differential equations

    CERN Document Server

    O'Neil, Peter V

    2014-01-01

    A broad introduction to PDEs with an emphasis on specialized topics and applications occurring in a variety of fields Featuring a thoroughly revised presentation of topics, Beginning Partial Differential Equations, Third Edition provides a challenging, yet accessible,combination of techniques, applications, and introductory theory on the subjectof partial differential equations. The new edition offers nonstandard coverageon material including Burger's equation, the telegraph equation, damped wavemotion, and the use of characteristics to solve nonhomogeneous problems. The Third Edition is or

  20. Obtención, purificación y caracterización de anticuerpos policlonales IgY desarrollados en gallina, dirigidos contra aislamientos colombianos de Giardia duodenalis.

    Directory of Open Access Journals (Sweden)

    Dabeiba Adriana García

    2005-12-01

    Full Text Available Introducción. El desarrollo de anticuerpos policlonales requiere de animales de laboratorio, generalmente, el conejo, que deben sangrarse para su obtención. Como alternativa, se han utilizado las gallinas. Objetivo. Desarrollar anticuerpos policlonales IgY anti-Giardia duodenalis y evaluar diferentes métodos para su purificación a partir de yema de huevo. Materiales y métodos. Se inmunizaron tres gallinas intramuscularmente con trofozoítos del parásito: las inmunizaciones se realizaron a los 0, 15, 30, 45, 60, 90 y 120 días. Se recolectaron huevos en cada etapa de la inmunización y se purificó la IgY por deslipidación (D y precipitación (P mediante cinco protocolos diferentes: M1: (P: sulfato de amonio/D: dextrán sulfato-cloruro de calcio, M2: (D: dextrán sulfato-cloruro de calcio/P: sulfato de amonio, M3: (D: cloroformo/ P: sulfato de amonio 50%, M4: (D: solución A/P:solución B y M5: (D: cloroformo/P: sulfato de amonio 30%. Se realizó evaluación inmunoquímica de la IgY anti-Giardia duodenalis mediante inmunodifusión, contrainmunoelectroforesis e inmunoelectrotransferencia (Western blot; la pureza de IgY por SDS-PAGE en presencia y ausencia de reductor y la concentración de la inmunoglobulina (mg/mL por espectrofotometría y densitometría. Resultados. La IgY anti-G. duodenalis mediante evaluación inmunoquímica presentó títulos hasta de 1:32. La inmunoglobulina en ausencia de reductor mostró una banda de 180 kd y en su presencia bandas de 30 y 68 kd, características de sus cadenas liviana y pesada, respectivamente. Las mayores concentraciones de inmunoglobulina se recuperaron con el método dos (M2, 4,6 mg de IgY por mL de yema de partida. Conclusiones. Por su facilidad y economía de producción en gallinas, los anticuerpos policlonales IgY anti-Giardia así obtenidos podrán utilizarse para desarrollar inmunoensayos que detecten el parásito en eluídos de heces.