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Sample records for giardia lamblia cysts

  1. Improved In Vitro Excystation Procedure for Giardia lamblia Cysts

    Rice, Eugene W.; Schaefer, Frank W.

    1981-01-01

    Giardia lamblia cysts obtained from human symptomatic and asymptomatic donors were excysted in vitro. Excystation averaged 87% for cysts from symptomatic donors and 70% for cysts from asymptomatic donors.

  2. Immunofluorescence and morphology of Giardia lamblia cysts exposed to chlorine.

    Sauch, J F; Berman, D

    1991-01-01

    Giardia cyst-like objects detected by immunofluorescence in chlorinated water samples often cannot be positively identified by their morphological appearance. To determine the effect of chlorine on cyst immunofluorescence and morphology, Giardia lamblia cysts were exposed to chlorine for 48 h. The majority of cysts exposed to chlorine concentrations of 1 to 11 mg/liter at 5 and 15 degrees C lost their internal morphological characteristics necessary for identification, but most of them were s...

  3. Effect of Chlorine on Giardia lamblia Cyst Viability

    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...

  4. Effect of Valeriana officinalis hydroalcoholic extract on Giardia lamblia cysts

    Mohamadi Mona

    2015-10-01

    Full Text Available ntroduction: Giardia lamblia is an important and prevalent parasitic cause of diarrhea andgastroenteritis. Regarding the significance of giardiasis treatment particularly by medicinal plantsand G. lamblia resistance to chemical drugs, this study was conducted to study in vitro effect ofValeriana officinalis hydroalcoholic extract on G. lamblia cysts.Methods: In this experimental, laboratory study the hydroalcoholic extract of V. officinalis atconcentrations of 12.5, 25, 50, 100, and 200 mg/mL was applied on G. lamblia cysts. The findingswere compared with controls.Results: Mean results of the effect of V. officinalis hydroalcoholic extract at different concentrationson G. lamblia cysts after 1, 6 and 24 hours demonstrated that the extract at all concentrations causeda notable decrease in alive cysts, with more intensive effect at 100 and 200 mg/mL concentrationsand 100% fatality after 1 hour. As the extract concentration decreased, the speed of G. lamblia cystsinhibition declined.Conclusion: V. officinalis hydroalcoholic extract might be recommended as an effective compoundfor removing G. lamblia protozoan cysts, although further studies are needed to show this effect onhuman.

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

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

    1993-01-01

    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...

  6. Degradation of Giardia lamblia cysts in mixed human and swine wastes.

    Deng, M.Y.; Cliver, D. O.

    1992-01-01

    This study was conducted to determine the persistence of Giardia lamblia cysts in mixed septic tank effluent and swine manure slurry and to correlate fluorescein diacetate-propidium iodide staining of G. lamblia cysts with their morphology under low-voltage scanning electron microscopy. Under field conditions, G. lamblia cysts were degraded more rapidly in the mixed waste than in the control Dulbecco's phosphate-buffered saline (PBS). For total and viable cysts, the mixed waste had D values (...

  7. ENCYSTATION AND EXPRESSION OF CYST ANTIGENS BY 'GIARDIA LAMBLIA' IN VITRO

    The cyst form of Giardia lamblia is responsible for transmission of giardiasis, a major waterborne intestinal disease. These studies demonstrate for the first time expression of cyst antigens and encystation of G. lamblia in vitro by both morphologic and immunologic criteria. The...

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

    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.

  9. Infectivity of Giardia lamblia cysts obtained from wastewater treated with ultraviolet light.

    Li, Dong; Craik, Stephen A; Smith, Daniel W; Belosevic, Miodrag

    2009-07-01

    Several waterborne outbreaks of giardiasis have been linked to discharge of wastewater effluents into surface water. Little is known about the infectivity of Giardia lamblia cysts present in UV treated wastewater effluents. In this study, the infectivity of G. lamblia cysts, recovered from primary effluent and secondary effluent, both upstream and downstream of operating full-scale UV reactors at four wastewater treatment plants, was assessed using the Mongolian gerbil model. Infectivity of cysts obtained from the primary effluents was scored as either strong or moderate for induction of infection in gerbils at three out of four wastewater treatment plants. G. lamblia recovered from secondary effluent both upstream and downstream of the UV reactors caused weak infections in the gerbils. The probability of weak infections caused by inoculums of 50-1400 cysts per gerbil was, on the average, reduced by approximately 10% at the four wastewater UV installations with coliform reduction equivalent doses ranging from 6 to 18 mJ/cm2. The UV systems provided considerably less inactivation of the parasite than expected based on the UV dose response of Giardia reported in the literature. PMID:19467689

  10. In-vitro giardicidal effect of aqueous and alcoholic extracts of Asafoetida on Giardia lamblia cyst

    Mohammadreza Rezaiemanesh

    2012-05-01

    Full Text Available Background and Aim: Giardia lamblia, Giardiasis causative protozoa, is one of the most common etiologic agents of diarrhea throughout the world especially in Iran. Asafoetida, an oleo-gum-resin (called Anjodan in Farsi obtained from an Iranian endemic herb, Ferula Assa-foetida has been used in treating of different diseases, particularly parasitic ones. The aim of this study was in-vitro evaluating of the effect of Asafoetida aqueous and alcoholic extracts on Giardia lamblia cysts. Materials and Methods: 500 µl of each of 1.25, 2.5, 5 and 20 mg/ml concentrtions of asafoetida aqueous and ethanol extracts was added to 500 µl of purified Giardia cysts,respectively. The mixtures were kept at 4, 24 and 37°C. The Giardicidal activity of the extracts was measured 1, 2, 3, 4 and 5 hour (s after exposure through 0.1% eosin dye staining and microscopic enumeration method. The gathered data was analyzed by means of one- way variance, Pearson's correlation coefficient and Independent T-test. Results: The highest Giardicidal effect of Asafoetida ethanol extract was 100% at 37°C, belonging to 20 mg/ml and in the 4th hour after experiment, while the maximum Giardicidal effect of Asafoetida aqueous extract was 57.23% at the same temperature and with the same concentration, in the 5th hour. There was a significant difference between Giardicidal effect of ethanol and water extracts with all concentrations and at different whiles and temperatures (P<0.005. Giardicidal effect of both extracts significantly increased due to rising the concentration, time and temperature (P<0.0001. Conclusion: Ethanol and aqueous extracts of asafetida have in-vitro Giardicidal effect on Giardia lamblia cysts. Ethanol extract has more Giardicidal effect.

  11. Antibodies to cysts of Giardia lamblia in primary giardiasis and in the absence of giardiasis.

    Jokipii, L; Miettinen, A; Jokipii, A M

    1988-01-01

    The significance of serum antibodies binding to cysts of Giardia lamblia was evaluated by indirect immunofluorescence. Titers of 10 or higher were found in 85.6% of adults, who had probably never had giardiasis. Titers in 118 adults (geometric mean, 29.9) were higher than in 35 children (16.4), and titers in women (42.3) were higher than in men (20.0). Titers in 150 patients with primary giardiasis (80.4) were higher than in control adults, but overlapping precluded serological diagnosis. Tit...

  12. Rac Regulates Giardia lamblia Encystation by Coordinating Cyst Wall Protein Trafficking and Secretion

    Krtková, Jana; Thomas, Elizabeth B.; Alas, Germain C. M.; Schraner, Elisabeth M.; Behjatnia, Habib R.; Hehl, Adrian B.

    2016-01-01

    ABSTRACT Encystation of the common intestinal parasite Giardia lamblia involves the production, trafficking, and secretion of cyst wall material (CWM). However, the molecular mechanism responsible for the regulation of these sequential processes remains elusive. Here, we examined the role of GlRac, Giardia’s sole Rho family GTPase, in the regulation of endomembrane organization and cyst wall protein (CWP) trafficking. Localization studies indicated that GlRac is associated with the endoplasmic reticulum (ER) and the Golgi apparatus-like encystation-specific vesicles (ESVs). Constitutive GlRac signaling increased levels of the ER marker PDI2, induced ER swelling, reduced overall CWP1 production, and promoted the early maturation of ESVs. Quantitative analysis of cells expressing constitutively active hemagglutinin (HA)-tagged GlRac (HA-RacCA) revealed fewer but larger ESVs than control cells. Consistent with the phenotype of premature maturation of ESVs in HA-RacCA-expressing cells, constitutive GlRac signaling resulted in increased CWP1 secretion and, conversely, morpholino depletion of GlRac blocked CWP1 secretion. Wild-type cells unexpectedly secreted large quantities of CWP1 into the medium, and free CWP1 was used cooperatively during cyst formation. These results, in part, could account for the previously reported observation that G. lamblia encysts more efficiently at high cell densities. These studies of GlRac show that it regulates encystation at several levels, and our findings support its coordinating role as a regulator of CWP trafficking and secretion. The central role of GlRac in regulating membrane trafficking and the cytoskeleton, both of which are essential to Giardia parasitism, further suggests its potential as a novel target for drug development to treat giardiasis. PMID:27555307

  13. Survey on efficacy of chloroformic extract of Artemisia annua against Giardia lamblia trophozoite and cyst in vitro.

    Golami, Shirzad; Rahimi-Esboei, Bahman; Mousavi, Parisa; Marhaba, Zahra; Youssefi, Mohammad Reza; Rahimi, Mohammad Taghi

    2016-03-01

    Giardiasis is a parasitic cosmopolitan disease that the rate of infection in developing countries is considerable. This infection directly is associated with poor hygienic conditions, poor water quality control, and overcrowding. Reinfection and drug resistance are two major problems in endemic areas. Recently, researchers are concentrating on herbal drugs as a proper solution. Therefore, the objective of the present study was to survey on efficacy of chloroformic extract of Artemisia annua against Giardia lamblia trophozoite and cyst in vitro. G. lamblia cysts were prepared from faces of giardiasis patients from different hospitals of Mazandaran Medical University. Four concentrations (1, 10, 50 and 100 mg/ml) of chloroformic extract of A. annua were utilized for 1, 5, 30, 60 and 180 min. Viability of G. lamblia cysts was confirmed by 0.1 % Eosin staining. Cyst and trophozoite contact (intermix) of G. lamblia with extract of A. annua with variant concentrations (1, 10, 50 and 100 mg/ml) after 1 and 180 min caused following cyst and trophozoite elimination rates: (67, 69, 71 and 73 %), (65, 67, 67 and 72 %), (94, 96, 97 and 99 %) and (100, 100, 100 and 100 %), respectively. Authors from the current investigation draw a conclusion that chloroformic extract of A. annua has the ability to eliminate G. lamblia cysts and trophozoites in vitro. PMID:27065604

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

    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

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

    Konrad, Christian; Spycher, Cornelia; Hehl, Adrian B

    2010-04-01

    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 minimal Golgi sorting

  16. Automated 3D detection and classification of Giardia lamblia cysts using digital holographic microscopy with partially coherent source

    El Mallahi, A.; Detavernier, A.; Yourassowsky, C.; Dubois, F.

    2012-06-01

    Over the past century, monitoring of Giardia lamblia became a matter of concern for all drinking water suppliers worldwide. Indeed, this parasitic flagellated protozoan is responsible for giardiasis, a widespread diarrhoeal disease (200 million symptomatic individuals) that can lead immunocompromised individuals to death. The major difficulty raised by Giardia lamblia's cyst, its vegetative transmission form, is its ability to survive for long periods in harsh environments, including the chlorine concentrations and treatment duration used traditionally in water disinfection. Currently, there is a need for a reliable, inexpensive, and easy-to-use sensor for the identification and quantification of cysts in the incoming water. For this purpose, we investigated the use of a digital holographic microscope working with partially coherent spatial illumination that reduces the coherent noise. Digital holography allows one to numerically investigate a volume by refocusing the different plane of depth of a hologram. In this paper, we perform an automated 3D analysis that computes the complex amplitude of each hologram, detects all the particles present in the whole volume given by one hologram and refocuses them if there are out of focus using a refocusing criterion based on the integrated complex amplitude modulus and we obtain the (x,y,z) coordinates of each particle. Then the segmentation of the particles is processed and a set of morphological and textures features characteristic to Giardia lamblia cysts is computed in order to classify each particles in the right classes.

  17. EXPERIMENTAL INFECTION OF MONGREL DOGS WITH 'GIARDIA LAMBLIA' CYSTS AND CULTURED TROPHOZOITES

    In light of recent epidemiologic data implicating wild and domestic animals in the transmission of giardiasis, a study was undertaken to determine whether mongrel dogs could be infected with Giardia lamblia. After careful screening by stool examination (a minimum of six stools ex...

  18. Export of cyst wall material and Golgi organelle neogenesis in Giardia lamblia depend on endoplasmic reticulum exit sites.

    Faso, Carmen; Konrad, Christian; Schraner, Elisabeth M; Hehl, Adrian B

    2013-04-01

    Giardia lamblia parasitism accounts for the majority of cases of parasitic diarrheal disease, making this flagellated eukaryote the most successful intestinal parasite worldwide. This organism has undergone secondary reduction/elimination of entire organelle systems such as mitochondria and Golgi. However, trophozoite to cyst differentiation (encystation) requires neogenesis of Golgi-like secretory organelles named encystation-specific vesicles (ESVs), which traffic, modify and partition cyst wall proteins produced exclusively during encystation. In this work we ask whether neogenesis of Golgi-related ESVs during G. lamblia differentiation, similarly to Golgi biogenesis in more complex eukaryotes, requires the maintenance of distinct COPII-associated endoplasmic reticulum (ER) subdomains in the form of ER exit sites (ERES) and whether ERES are also present in non-differentiating trophozoites. To address this question, we identified conserved COPII components in G. lamblia cells and determined their localization, quantity and dynamics at distinct ERES domains in vegetative and differentiating trophozoites. Analogous to ERES and Golgi biogenesis, these domains were closely associated to early stages of newly generated ESV. Ectopic expression of non-functional Sar1 GTPase variants caused ERES collapse and, consequently, ESV ablation, leading to impaired parasite differentiation. Thus, our data show how ERES domains remain conserved in G. lamblia despite elimination of steady-state Golgi. Furthermore, the fundamental eukaryotic principle of ERES to Golgi/Golgi-like compartment correspondence holds true in differentiating Giardia presenting streamlined machinery for secretory organelle biogenesis and protein trafficking. However, in the Golgi-less trophozoites ERES exist as stable ER subdomains, likely as the sole sorting centres for secretory traffic. PMID:23094658

  19. Rapid imaging, detection and quantification of Giardia lamblia cysts using mobile-phone based fluorescent microscopy and machine learning.

    Koydemir, Hatice Ceylan; Gorocs, Zoltan; Tseng, Derek; Cortazar, Bingen; Feng, Steve; Chan, Raymond Yan Lok; Burbano, Jordi; McLeod, Euan; Ozcan, Aydogan

    2015-03-01

    Rapid and sensitive detection of waterborne pathogens in drinkable and recreational water sources is crucial for treating and preventing the spread of water related diseases, especially in resource-limited settings. Here we present a field-portable and cost-effective platform for detection and quantification of Giardia lamblia cysts, one of the most common waterborne parasites, which has a thick cell wall that makes it resistant to most water disinfection techniques including chlorination. The platform consists of a smartphone coupled with an opto-mechanical attachment weighing ~205 g, which utilizes a hand-held fluorescence microscope design aligned with the camera unit of the smartphone to image custom-designed disposable water sample cassettes. Each sample cassette is composed of absorbent pads and mechanical filter membranes; a membrane with 8 μm pore size is used as a porous spacing layer to prevent the backflow of particles to the upper membrane, while the top membrane with 5 μm pore size is used to capture the individual Giardia cysts that are fluorescently labeled. A fluorescence image of the filter surface (field-of-view: ~0.8 cm(2)) is captured and wirelessly transmitted via the mobile-phone to our servers for rapid processing using a machine learning algorithm that is trained on statistical features of Giardia cysts to automatically detect and count the cysts captured on the membrane. The results are then transmitted back to the mobile-phone in less than 2 minutes and are displayed through a smart application running on the phone. This mobile platform, along with our custom-developed sample preparation protocol, enables analysis of large volumes of water (e.g., 10-20 mL) for automated detection and enumeration of Giardia cysts in ~1 hour, including all the steps of sample preparation and analysis. We evaluated the performance of this approach using flow-cytometer-enumerated Giardia-contaminated water samples, demonstrating an average cyst capture

  20. 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

    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.

  1. DETECTION OF GIARDIA MURIS AND GIARDIA LAMBLIA CYSTS BY IMMUNOFLUORESCENCE IN ANIMAL TISSUES AND FECAL SAMPLES SUBJECTED TO CYCLES OF FREEZING AND THAWING

    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). iardia muris cysts were obtained from either animal carcasses, fecal pellet...

  2. MODELING INACTIVATION OF GIARDIA LAMBLIA

    Under the auspices of the Safe Drinking Water Act (SDWA)the U.S. EPA hasa promulgated the Surface Water Treatment Rule (SWTR) requiring public water systems using surface water to provide minimum disinfection to Control Giardia Lamblia, enteric virsues, and bacteria. The C-t con...

  3. The proteome landscape of Giardia lamblia encystation.

    Carmen Faso

    Full Text Available Giardia lamblia is an intestinal protozoan parasite required to survive in the environment in order to be transmitted to a new host. To ensure parasite survival, flagellated trophozoites colonizing the small intestine differentiate into non-motile environmentally-resistant cysts which are then shed in the environment. This cell differentiation process called encystation is characterized by significant morphological remodeling which includes secretion of large amounts of cyst wall material. Although much is known about the transcriptional regulation of encystation and the synthesis and trafficking of cyst wall material, the investigation of global changes in protein content and abundance during G. lamblia encystation is still unaddressed. In this study, we report on the quantitative analysis of the G. lamblia proteome during encystation using tandem mass spectrometry. Quantification of more than 1000 proteins revealed major changes in protein abundance in early, mid and late encystation, notably in constitutive secretory protein trafficking. Early stages of encystation were marked by a striking decrease of endoplasmic reticulum-targeted variant-specific surface proteins and significant increases in cytoskeleton regulatory components, NEK protein kinases and proteins involved in protein folding and glycolysis. This was in stark contrast to cells in the later stages of encystation which presented a surprisingly similar proteome composition to non-encysting trophozoites. Altogether these data constitute the first quantitative atlas of the Giardia proteome covering the whole process of encystation and point towards an important role for post-transcriptional control of gene expression in Giardia differentiation. Furthermore, our data provide a valuable resource for the community-based annotation effort of the G. lamblia genome, where almost 70% of all predicted gene models remains "hypothetical".

  4. The proteome landscape of Giardia lamblia encystation.

    Faso, Carmen; Bischof, Sylvain; Hehl, Adrian B

    2013-01-01

    Giardia lamblia is an intestinal protozoan parasite required to survive in the environment in order to be transmitted to a new host. To ensure parasite survival, flagellated trophozoites colonizing the small intestine differentiate into non-motile environmentally-resistant cysts which are then shed in the environment. This cell differentiation process called encystation is characterized by significant morphological remodeling which includes secretion of large amounts of cyst wall material. Although much is known about the transcriptional regulation of encystation and the synthesis and trafficking of cyst wall material, the investigation of global changes in protein content and abundance during G. lamblia encystation is still unaddressed. In this study, we report on the quantitative analysis of the G. lamblia proteome during encystation using tandem mass spectrometry. Quantification of more than 1000 proteins revealed major changes in protein abundance in early, mid and late encystation, notably in constitutive secretory protein trafficking. Early stages of encystation were marked by a striking decrease of endoplasmic reticulum-targeted variant-specific surface proteins and significant increases in cytoskeleton regulatory components, NEK protein kinases and proteins involved in protein folding and glycolysis. This was in stark contrast to cells in the later stages of encystation which presented a surprisingly similar proteome composition to non-encysting trophozoites. Altogether these data constitute the first quantitative atlas of the Giardia proteome covering the whole process of encystation and point towards an important role for post-transcriptional control of gene expression in Giardia differentiation. Furthermore, our data provide a valuable resource for the community-based annotation effort of the G. lamblia genome, where almost 70% of all predicted gene models remains "hypothetical". PMID:24391747

  5. Analysis of Giardin expression during encystation of Giardia lamblia

    The present study analyzed giardin transcription in trophozoites and cysts during encystation of Giardia lamblia. Encystment was induced using standard methods, and the number of trophozoites and cysts were counted at various time-points during encystation. At all time points, RNA from both stages...

  6. Antigenic conservation and variation in Giardia cysts from various vertebrate hosts.

    Riley, E T; Stibbs, H H

    1989-01-01

    Monoclonal antibodies produced against Giardia muris cysts reacted in indirect immunofluorescence with homologous cysts and cysts from a Giardia-infected wild Norway rat but did not cross-react with Giardia lamblia cysts of human, dog, or beaver sources. Another monoclonal antibody raised against Giardia simoni cysts from the Norway rat reacted with homologous cysts (rat) and cross-reacted with cysts from a cow. The demonstration of antigenic differences at the cyst surfaces of Giardia organi...

  7. Host defences against Giardia lamblia.

    Lopez-Romero, G; Quintero, J; Astiazarán-García, H; Velazquez, C

    2015-08-01

    Giardia spp. is a protozoan parasite that inhabits the upper small intestine of mammals and other species and is the aetiological agent of giardiasis. It has been demonstrated that nitric oxide, mast cells and dendritic cells are the first line of defence against Giardia. IL-6 and IL-17 play an important role during infection. Several cytokines possess overlapping functions in regulating innate and adaptive immune responses. IgA and CD4(+) T cells are fundamental to the process of Giardia clearance. It has been suggested that CD4(+) T cells play a double role during the anti-Giardia immune response. First, they activate and stimulate the differentiation of B cells to generate Giardia-specific antibodies. Second, they act through a B-cell-independent mechanism that is probably mediated by Th17 cells. Several Giardia proteins that stimulate humoral and cellular immune responses have been described. Variant surface proteins, α-1 giardin, and cyst wall protein 2 can induce host protective responses to future Giardia challenges. The characterization and evaluation of the protective potential of the immunogenic proteins that are associated with Giardia will offer new insights into host-parasite interactions and may aid in the development of an effective vaccine against the parasite. PMID:26072999

  8. Whole genome sequencing of clinical isolates of Giardia lamblia

    Hanevik, Kurt; Bakken, R.; Brattbakk, Hans-Richard; Saghaug, Christina Skår; Langeland, Nina

    2015-01-01

    Clinical isolates from protozoan parasites such as Giardia lamblia are at present practically impossible to culture. By using simple cyst purification methods, we show that Giardia whole genome sequencing of clinical stool samples is possible. Immunomagnetic separation after sucrose gradient flotation gave superior results compared to sucrose gradient flotation alone. The method enables detailed analysis of a wide range of genes of interest for genotyping, virulence and drug resistance.

  9. Giardia lamblia infections in adult mice.

    Byrd, L G; Conrad, J T; Nash, T E

    1994-01-01

    An adult mouse-Giardia lamblia model was developed and used to study host-parasite interactions, including antigenic variation. The H7/1 clone of isolate GS infected mice consistently and produced infections in 14 mouse strains tested. Infection patterns were mouse strain and Giardia isolate dependent. Antigenic variation occurred in immunocompetent mice but not in mice with severe combined immunodeficiency.

  10. Rab11 and actin cytoskeleton participate in Giardia lamblia encystation, guiding the specific vesicles to the cyst wall.

    Araceli Castillo-Romero

    Full Text Available BACKGROUND: Giardia passes through two stages during its life cycle, the trophozoite and the cyst. Cyst formation involves the synthesis of cyst wall proteins (CWPs and the transport of CWPs into encystation-specific vesicles (ESVs. Active vesicular trafficking is essential for encystation, but the molecular machinery driving vesicular trafficking remains unknown. The Rab proteins are involved in the targeting of vesicles to several intracellular compartments through their association with cytoskeletal motor proteins. METHODOLOGY AND PRINCIPAL FINDINGS: In this study, we found a relationship between Rab11 and the actin cytoskeleton in CWP1 transport. Confocal microscopy showed Rab11 was distributed throughout the entire trophozoite, while in cysts it was translocated to the periphery of the cell, where it colocalized with ESVs and microfilaments. Encystation was also accompanied by changes in rab11 mRNA expression. To evaluate the role of microfilaments in encystation, the cells were treated with latrunculin A. Scanning electron microscopy showed this treatment resulted in morphological damages to encysted parasites. The intensity of fluorescence-labeled Rab11 and CWP1 in ESVs and cyst walls was reduced, and rab11 and cwp1 mRNA levels were down-regulated. Furthermore, knocking down Rab11 with a hammerhead ribozyme resulted in an up to 80% down-regulation of rab11 mRNA. Although this knockdown did not appear lethal for trophozoites and did not affect cwp1 expression during the encystation, confocal images showed CWP1 was redistributed throughout the cytosol. CONCLUSIONS AND SIGNIFICANCE: Our results indicate that Rab11 participates in the early and late encystation stages by regulating CWP1 localization and the actin-mediated transport of ESVs towards the periphery. In addition, alterations in the dynamics of actin affected rab11 and cwp1 expression. Our results provide new information about the molecules involved in Giardia encystation and

  11. EFFECT OF HALOGENS ON 'GIARDIA' CYST VIABILITY

    The objective of this research was to determine the effect of chlorine and other disinfecting agents on Giardia lamblia cyst viability. The agents studied included free residual chlorine and six different methods recommended for emergency disinfection of small quantities of water...

  12. Identification of chitin as a structural component of Giardia cysts.

    Ward, H D; Alroy, J.; Lev, B. I.; Keusch, G T; Pereira, M.E.

    1985-01-01

    The intestinal parasite Giardia lamblia is a significant cause of diarrheal disease, which is perpetuated by the infective cyst form of the parasite. Although a rational approach to the control of giardiasis would be to inhibit cyst formation, nothing is known of the chemical composition of the cyst wall or of its biosynthesis. In these studies, we have shown that chitin is a major structural component of G. lamblia and G. muris cyst walls. This conclusion is based on the finding that chitina...

  13. Tonic Shock Induces Detachment of Giardia lamblia

    Hansen, Wendy R.; Fletcher, Daniel A

    2008-01-01

    Background The parasite Giardia lamblia must remain attached to the host small intestine in order to proliferate and subsequently cause disease. However, little is known about the factors that may cause detachment in vivo, such as changes in the aqueous environment. Osmolality within the proximal small intestine can vary by nearly an order of magnitude between host fed and fasted states, while pH can vary by several orders of magnitude. Giardia cells are known to regulate their volume when ex...

  14. PURE CULTURE METHOD: GIARDIA LAMBLIA FROM DIFFERENT STOOL SAMPLES

    H.A YOUSEFI

    2000-03-01

    Full Text Available Introduction. Giardiasis is one of the health problems in the world including Iran. To determine the biochemical and biological problems and also identification of various strains, it is essential to obtain pure culture and then mass production of Giardia lamblia. The goal of this study was to isolate this protozoa purely.
    Methods. Giardia lamblia cysts were isolated from 50 stool samples by use of floating of a four - layer of sucrose method. The cysts were transfered to an inducing solution. Subsequently, they were cultured in a modified culture medium (TYIS-33. Following excystation of trophozoite and its multiplication, the parasite was caltured and purified.
    Findings. Excitation of trophozoite was observed in 40 samples (80 percent from which 22 samples (55 percent yielded pure culture. The doubling time was approximately 13hr and the peak of parasite was observed between third and fourth days.
    Conclusion. The proliferation and growth rate of Giardia lamblia have enabled us to use this method widely. Cystein and ascorbic acid which are present in the induction solution, have a key role in excystation of trophozoite. Purification and passage of samples has facilitated the culture of this parasite in vitro. Therefore this method has yielded better results in comparison with other studies. This is probably due to a decrease in the amount of bovine bile or using different strains of Giardia lamblia in the present study.

  15. Effect of corticosteroid and irradiation on experimental Giardia lamblia infection in mice

    Following infection with the parasite, Giardia lamblia, the faecal excretion rate of these cysts was studied in mice pre-treated with cortisone and/or whole body irradiation compared to controls. The cortisone/irradiation treatment increased the susceptibility to infection, as shown by the higher cyst excretion rate. Thus these treatments presumably depressed the cellular and humoral immunity normally present in G. lamblia infected mice. (UK)

  16. Isolation and identification of a Giardia lamblia-specific stool antigen (GSA 65) useful in coprodiagnosis of giardiasis.

    Rosoff, J D; Stibbs, H H

    1986-01-01

    A Giardia lamblia-specific antigen (GSA 65) was isolated from stools of G. lamblia-positive patients by crossed- and line-immunoelectrophoresis and counterimmunoelectrophoresis (CIE) in agarose by using rabbit antiserum prepared against G. lamblia cysts. CIE with rabbit anti-GSA 65 monospecific antiserum revealed that GSA 65 was present in aqueous stool eluates of giardiasis patients and in cysts and trophozoites of the parasite. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of im...

  17. Giardia lamblia and Helicobater pylori Coinfection

    R Shafie

    2009-03-01

    Full Text Available "nBackground: Giardia lamblia and Helicobacter pylori are two flagellate microorganisms that grow in duodenum and stom­ach. The aim of this study was to evaluate the prevalence of them in patients with dyspepsia and other GI disorders. "nMethods: In this cross-sectional study, co-infection of above-mentioned agents was investigated in a group of 130 patients [me­dian age of 40 yr (range=11-79 including 76 males (58.8%] with dyspepsia using three methods of duodenal aspiration sam­ple, duodenal biopsy samples and evaluation of stool samples."nResults: : From 105 patients (59 males, 46 females, median age 40 years, range 11-79 entering this study from 3 hospitals, 4 patients (3.8% had G. lamblia and 61 patients (58% had H. pylori. All 4 patients infected by Giardia had also H. pylori infec­tion. Tenesmus (3 out of 4 patients was the most common symptom in patients with H. pylori infection (48 out of 61 pa­tients was reflux. Other symptoms in patients infected with both organisms (4 patients included diarrhea (2 cases, weight loss (2 cases, and loss of appetite (1 case but no report of vomiting."nConclusion: In patients co-infected with Giardia, H.pylori differentiation by physical examination is not possible. So in those patients with positive Rapid Urease Test (RUT, stool examination for Giardia detection is recommended. In addition, met­ronidazole (broad spectrum, anti-protozoal drug can be useful in H. pylori infection.

  18. Tonic shock induces detachment of Giardia lamblia.

    Wendy R Hansen

    Full Text Available BACKGROUND: The parasite Giardia lamblia must remain attached to the host small intestine in order to proliferate and subsequently cause disease. However, little is known about the factors that may cause detachment in vivo, such as changes in the aqueous environment. Osmolality within the proximal small intestine can vary by nearly an order of magnitude between host fed and fasted states, while pH can vary by several orders of magnitude. Giardia cells are known to regulate their volume when exposed to changes in osmolality, but the short-timescale effects of osmolality and pH on parasite attachment are not known. METHODOLOGY AND PRINCIPAL FINDINGS: We used a closed flow chamber assay to test the effects of rapid changes in media osmolality, tonicity, and pH on Giardia attachment to both glass and C2(Bbe-1 intestinal cell monolayer surfaces. We found that Giardia detach from both surfaces in a tonicity-dependent manner, where tonicity is the effective osmolality experienced by the cell. Detachment occurs with a characteristic time constant of 25 seconds (SD = 10 sec, n = 17 in both hypo- and hypertonic media but is otherwise insensitive to physiologically relevant changes in media composition and pH. Interestingly, cells that remain attached are able to adapt to moderate changes in tonicity. By exposing cells to a timed pattern of tonicity variations and adjustment periods, we found that it is possible to maximize the tonicity change experienced by the cells, overcoming the adaptive response and resulting in extensive detachment. CONCLUSIONS AND SIGNIFICANCE: These results, conducted with human-infecting Giardia on human intestinal epithelial monolayers, highlight the ability of Giardia to adapt to the changing intestinal environment and suggest new possibilities for treatment of giardiasis by manipulation of tonicity in the intestinal lumen.

  19. Morphological Studies of Nucleologenesis in Giardia lamblia.

    Lara-Martínez, Reyna; De Lourdes Segura-Valdez, María; De La Mora-De La Mora, Ignacio; López-Velázquez, Gabriel; JimÉnez-García, Luis Felipe

    2016-05-01

    The nucleolus is a nuclear organelle involved in ribosome biogenesis. In most eukaryotes this structure disperses during prophase through anaphase and reorganizes at telophase by a process known as nucleologenesis. This process involves new transcription of ribosomal DNA at the nucleolar organizer region and the formation of prenucleolar bodies fusing to it. In Giardia lamblia, for a long time considered the only anucleolated eukaryote, a very small nucleolus has been recently described. In order to evaluate whether nucleologenesis is also present in Giardia, we analyzed the distribution of nucleolar material during telophase using different light and electron microscopy techniques including silver staining for the nucleolar organizer. Results indicate that in G. lamblia, nucleolar elements persist mainly as an intranuclear peripheral organelle during all stages of division, including telophase, however, no prenucleolar bodies are detected in the nucleoplasm. Therefore, in the parasite, nucleolar material is present throughout cell division including telophase and formation of prenucleolar bodies may not be required for nucleologenesis. Anat Rec, 299:549-556, 2016. © 2016 Wiley Periodicals, Inc. PMID:26833978

  20. Survival of Giardia lamblia trophozoites after exposure to UV light.

    Li, Dong; Craik, Stephen A; Smith, Daniel W; Belosevic, Miodrag

    2008-01-01

    The ability of Giardia lamblia trophozoites to reproduce after exposure to different fluences of UV radiation was determined using an in vitro-cultured method. The rate of parasite reproduction following UV exposure was measured by direct enumeration of trophozoites cultured in Diamond's Trypticase Yeast extract-Iron (TYI)-S-33 medium. The results suggested that some G. lamblia trophozoites may survive or are reactivated following exposure to UV fluences up to 10 mJ cm(-2). In addition, trophozoites exposed to a UV fluence of 1 mJ cm(-2) were infectious to Mongolian gerbils. Evidence of survival or reactivation at UV fluences of 20 and 40 mJ cm(-2) was ambiguous and statistically inconclusive, while at 100 mJ cm(-2) there was no evidence of survival or reactivation. This finding may have implications for criteria used by the drinking water and wastewater treatment industry to ensure safe reduction of G. lamblia cysts by UV disinfection processes. PMID:17995955

  1. Molecular characterization of the cis-prenyltransferase of Giardia lamblia

    Grabińska, Kariona A.; Cui, Jike; Chatterjee, Aparajita; Guan, Ziqiang; Raetz, Christian R. H.; Robbins, Phillips W.; Samuelson, John

    2010-01-01

    Giardia lamblia, the protist that causes diarrhea, makes an Asn-linked-glycan (N-glycan) precursor that contains just two sugars (GlcNAc2) attached by a pyrophosphate linkage to a polyprenol lipid. Because the candidate cis-prenyltransferase of Giardia appears to be more similar to bacterial enzymes than to those of most eukaryotes and because Giardia is missing a candidate dolichol kinase (ortholog to Saccharomyces cerevisiae SEC59 gene product), we wondered how Giardia synthesizes dolichol ...

  2. Giardia lamblia: Molecular Studies of an Early Branching Eukaryote

    The rapid advance in our understanding of the biology of Giardia lamblia over the last several years is due in part to the complete DNA sequencing of the 11.7 Mb genome of this diplomonad. Insight on the molecular nature of G. lamblia has been gained by searching the genome using query sequences fr...

  3. A Lesson in Survival, by Giardia lamblia

    Andrea A. S. Rópolo

    2010-01-01

    Full Text Available In the relationships between host and parasites, there is a cross-talk that involves diverse mechanisms developed by two different genetic systems during years of evolution. On the one hand, immunocompetent hosts have developed effective innate and acquired immune responses that are used to restrict or avoid parasitism. On the other hand, parasites evade the immune response, expressing different antigens on their surface or by using other specific mechanisms, such as nutrient depletion. In this review, we analyze the survival mechanisms used by the protozoan parasite Giardia lamblia during infection. In particular, we examine the multiple roles played by the enzyme arginine deiminase during colonization of the gut, also involving the parasite's mechanism of antigenic variation. Potential drug targets for the treatment of giardiasis are also discussed.

  4. Reconstruction of Sugar Metabolic Pathways of Giardia lamblia

    Jian Han; Collins, Lesley J.

    2012-01-01

    Giardia lamblia is an “important” pathogen of humans, but as a diplomonad excavate it is evolutionarily distant from other eukaryotes and relatively little is known about its core metabolic pathways. KEGG, the widely referenced site for providing information of metabolism, does not yet include many enzymes from Giardia species. Here we identify Giardia’s core sugar metabolism using standard bioinformatic approaches. By comparing Giardia proteomes with known enzymes from other species, we have...

  5. Attachment of Giardia lamblia to rat intestinal epithelial cells.

    Inge, P M; Edson, C M; Farthing, M J

    1988-01-01

    The human enteric protozoan, Giardia lamblia, has surface membrane lectin activity which mediates parasite adherence to erythrocytes. To determine whether an intestinal binding site exists for this lectin we have studied the interaction in vitro between axenically cultured Giardia trophozoites and isolated rat intestinal epithelial cells. Scanning electron microscopy showed that Giardia attached to the apical microvillus membrane and basolateral membrane of rat enterocytes. Any location on th...

  6. Chitin synthetase in encysting Giardia lamblia and Entamoeba invadens

    Giardia lamblia (Gl) and Entamoeba invadens (Ei) are protozoan parasites with two morphologic stages in their life cycles. Motile trophozoites colonize the intestine of humans and reptiles respectively. Water resistant cysts, which can survive outside the host, transmit infection. In vitro cyst formation of Ei from trophozoites has been reported, and the authors have recently induced in vitro encystation of Gl. Although the cyst walls of both parasites contain chitin, it synthesis by encysting trophozoites has not been reported. The authors now show that encystation conditions greatly increase chitin synthetase (CS) specific activity (incorporation of 3H GlcNAc from UDP-GlcNAc into TCA-or alcohol-precipitable material). Extracts of encysting Gl incorporated 3.6 nmol/mg protein in 5 hr compared to < 0.005 in controls. Extracts of encysting Fi incorporated 4.8 n mol/mg protein, compared to 1.7 in the control. CS activity of both parasites requires preformed chitin. The Gl enzyme requires a reducing agent, is inhibited by digitonin and the CS inhibitors, polyoxin D and Nikkomycin, but not by tunicamycin. The product is digested by chitinase. Ei enzyme does not require a reducing agent and is stimulated by 1 mg/ml digitonin, but inhibited by higher concentrations. These studies demonstrate CS enzymes which may play important roles in encystation of Gl and Ei

  7. Chitin synthetase in encysting Giardia lamblia and Entamoeba invadens

    Das, S.; Gillin, F.D.

    1987-05-01

    Giardia lamblia (Gl) and Entamoeba invadens (Ei) are protozoan parasites with two morphologic stages in their life cycles. Motile trophozoites colonize the intestine of humans and reptiles respectively. Water resistant cysts, which can survive outside the host, transmit infection. In vitro cyst formation of Ei from trophozoites has been reported, and the authors have recently induced in vitro encystation of Gl. Although the cyst walls of both parasites contain chitin, it synthesis by encysting trophozoites has not been reported. The authors now show that encystation conditions greatly increase chitin synthetase (CS) specific activity (incorporation of /sup 3/H GlcNAc from UDP-GlcNAc into TCA-or alcohol-precipitable material). Extracts of encysting Gl incorporated 3.6 nmol/mg protein in 5 hr compared to < 0.005 in controls. Extracts of encysting Fi incorporated 4.8 n mol/mg protein, compared to 1.7 in the control. CS activity of both parasites requires preformed chitin. The Gl enzyme requires a reducing agent, is inhibited by digitonin and the CS inhibitors, polyoxin D and Nikkomycin, but not by tunicamycin. The product is digested by chitinase. Ei enzyme does not require a reducing agent and is stimulated by 1 mg/ml digitonin, but inhibited by higher concentrations. These studies demonstrate CS enzymes which may play important roles in encystation of Gl and Ei.

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

    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.

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

    Semíramis Guimarães

    2002-02-01

    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.

  10. Proteomics of secretory and endocytic organelles in Giardia lamblia.

    Petra B Wampfler

    Full Text Available Giardia lamblia is a flagellated protozoan enteroparasite transmitted as an environmentally resistant cyst. Trophozoites attach to the small intestine of vertebrate hosts and proliferate by binary fission. They access nutrients directly via uptake of bulk fluid phase material into specialized endocytic organelles termed peripheral vesicles (PVs, mainly on the exposed dorsal side. When trophozoites reach the G2/M restriction point in the cell cycle they can begin another round of cell division or encyst if they encounter specific environmental cues. They induce neogenesis of Golgi-like organelles, encystation-specific vesicles (ESVs, for regulated secretion of cyst wall material. PVs and ESVs are highly simplified and thus evolutionary diverged endocytic and exocytic organelle systems with key roles in proliferation and transmission to a new host, respectively. Both organelle systems physically and functionally intersect at the endoplasmic reticulum (ER which has catabolic as well as anabolic functions. However, the unusually high degree of sequence divergence in Giardia rapidly exhausts phylogenomic strategies to identify and characterize the molecular underpinnings of these streamlined organelles. To define the first proteome of ESVs and PVs we used a novel strategy combining flow cytometry-based organelle sorting with in silico filtration of mass spectrometry data. From the limited size datasets we retrieved many hypothetical but also known organelle-specific factors. In contrast to PVs, ESVs appear to maintain a strong physical and functional link to the ER including recruitment of ribosomes to organelle membranes. Overall the data provide further evidence for the formation of a cyst extracellular matrix with minimal complexity. The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium with the dataset identifier PXD000694.

  11. Proteomics of secretory and endocytic organelles in Giardia lamblia.

    Wampfler, Petra B; Tosevski, Vinko; Nanni, Paolo; Spycher, Cornelia; Hehl, Adrian B

    2014-01-01

    Giardia lamblia is a flagellated protozoan enteroparasite transmitted as an environmentally resistant cyst. Trophozoites attach to the small intestine of vertebrate hosts and proliferate by binary fission. They access nutrients directly via uptake of bulk fluid phase material into specialized endocytic organelles termed peripheral vesicles (PVs), mainly on the exposed dorsal side. When trophozoites reach the G2/M restriction point in the cell cycle they can begin another round of cell division or encyst if they encounter specific environmental cues. They induce neogenesis of Golgi-like organelles, encystation-specific vesicles (ESVs), for regulated secretion of cyst wall material. PVs and ESVs are highly simplified and thus evolutionary diverged endocytic and exocytic organelle systems with key roles in proliferation and transmission to a new host, respectively. Both organelle systems physically and functionally intersect at the endoplasmic reticulum (ER) which has catabolic as well as anabolic functions. However, the unusually high degree of sequence divergence in Giardia rapidly exhausts phylogenomic strategies to identify and characterize the molecular underpinnings of these streamlined organelles. To define the first proteome of ESVs and PVs we used a novel strategy combining flow cytometry-based organelle sorting with in silico filtration of mass spectrometry data. From the limited size datasets we retrieved many hypothetical but also known organelle-specific factors. In contrast to PVs, ESVs appear to maintain a strong physical and functional link to the ER including recruitment of ribosomes to organelle membranes. Overall the data provide further evidence for the formation of a cyst extracellular matrix with minimal complexity. The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium with the dataset identifier PXD000694. PMID:24732305

  12. [Giardia lamblia as a rare cause of reactive arthritis].

    Krol, Arkadiusz

    2013-12-01

    Giardiasis is a disease of gut, which is caused by the non-invasive (it does not pass the gut/blood barrier) protozoan parasite Giardia lamblia. It infects humans and animals like beavers, dogs and cattle. Contaminated water or uncooked food is a major source of transmission and G. lamblia occurs worldwide. High-risk groups are young children, travellers and immunocompromised individuals. Good hand hygiene is necessary to prevent the transmission. PMID:25353256

  13. The Study of the Multilayer Filtration Process Efficiency on Giardia lamblia Elimination in Isfahan Water Treatment Plant

    Zahra Mosaviyan; Ali-Asghar Rastegari; Saeed Abedi

    2014-01-01

    Introduction: Giardia lamblia is a waterborne highly infectious protozoan parasite capable of causing gastrointestinal illness. The multilayer filtration is used in many applications such as turbidity removes from surface waters and Bacteria, Viruses and protozoan removes. This study was investigated in full-scale the efficiency of filtration process during water treatment that remove Giardia cyst in water at Isfahan province. Materials and methods: We used Information Collection Rule meth...

  14. Drug Resistance in the Microaerophilic Parasite Giardia lamblia

    Leitsch, David

    2015-01-01

    The microaerophilic parasite Giardia lamblia is a causative agent of dysentery affecting hundreds of millions of people around the globe every year. The symptoms of the disease, commonly referred to as giardiasis, are diarrhea, nausea, and malabsorption. Treatment of giardiasis is exclusively based on chemotherapy with antigiardial drugs, including metronidazole, albendazole, and nitazoxanide. In this review, all drugs currently used in the treatment of Giardia infections are discussed with a...

  15. Sensitive and Rapid Detection of Giardia lamblia Infection in Pet Dogs using Loop-Mediated Isothermal Amplification

    Jie LI; Wang, Peiyuan; ZHANG, Aiguo; Zhang, Ping; Alsarakibi, Muhamd; Li, Guoqing

    2013-01-01

    Giardia lamblia is recognized as one of the most prevalent parasites in dogs. The present study aimed to establish a loop-mediated isothermal amplification (LAMP) assay for rapid and specific detection of G. lamblia from dogs. The fecal samples were collected and prepared for microscopic analysis, and then the genomic DNA was extracted directly from purified cysts. The concentration of DNA samples of G. lamblia were diluted by 10-fold serially ranging from 10-1 to 10-5 ng/µl for LAMP and PCR ...

  16. Azasterols impair Giardia lamblia proliferation and induces encystation

    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 IC50 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

  17. Detecting Cryptosporidium parvum and Giardia lamblia by coagulation concentration and real-time PCR quantification

    Huining ZHANG; Xiaohu Zhang; Shuting ZHANG; Bo WEI; Qipei JIANG; Xin YU

    2013-01-01

    Rapid and sensitive pathogen detection methods are essential for the effective functioning of the water treatment industry, yet for many pathogens, effective detection and removal methods are still lacking. Cryptosporidium parvum oocysts and Giardia lamblia cysts are two of the most common waterborne pathogens currently infecting the water supply. In this study, a new method was developed for the detection of Cryptosporidium parvum oocysts and Giardia lamblia cysts. The method includes multi-steps as coagulation concentration of (oo)cysts in water, the dissolution of the resulting flocs into a small volume using acid, filtration of the (oo)cysts solution, and DNA extraction, purification, and examination using real-time PCR. The method was tested using spiked tap water and reservoir water as references, and the mean recovery ranged from 19.6% to 97.6% for oocysts, and from 51.4% to 98.7% for cysts. The method is economical and convenient, and is especially suitable for relatively high turbidity surface water.

  18. Giardia Cyst Wall Protein 1 Is a Lectin That Binds to Curled Fibrils of the GalNAc Homopolymer

    Chatterjee, Aparajita; Carpentieri, Andrea; Ratner, Daniel M.; Bullitt, Esther; Catherine E. Costello; Robbins, Phillips W.; Samuelson, John

    2010-01-01

    The infectious and diagnostic stage of Giardia lamblia (also known as G. intestinalis or G. duodenalis) is the cyst. The Giardia cyst wall contains fibrils of a unique β-1,3-linked N-acetylgalactosamine (GalNAc) homopolymer and at least three cyst wall proteins (CWPs) composed of Leu-rich repeats (CWPLRR) and a C-terminal conserved Cys-rich region (CWPCRR). Our goals were to dissect the structure of the cyst wall and determine how it is disrupted during excystation. The intact Giardia cyst wa...

  19. Giardia lamblia Attachment Force Is Insensitive to Surface Treatments

    Hansen, W. R.; Tulyathan, O.; Dawson, S. C.; Cande, W Z; Fletcher, D. A.

    2006-01-01

    Giardia lamblia cell populations show 90% detachment from glass under normal forces of 2.43 ± 0.33 nN applied by centrifugation. Detachment forces were not significantly different for cells attached to positively charged, hydrophobic, or inert surfaces than for cells attached to plain glass. The insensitivity of attachment force to surface treatment is consistent with a suction-based mechanism of attachment.

  20. What Entamoeba histolytica and Giardia lamblia tell us about the evolution of eukaryotic diversity

    J Samuelson

    2002-11-01

    Entamoeba histolytica and Giardia lamblia are microaerophilic protists, which have long been considered models of ancient pre-mitochondriate eukaryotes. As transitional eukaryotes, amoebae and giardia appeared to lack organelles of higher eukaryotes and to depend upon energy metabolism appropriate for anaerobic conditions, early in the history of the planet. However, our studies have shown that amoebae and giardia contain splicoeosomal introns, ras-family signal-transduction proteins, ATP-binding casettes (ABC)-family drug transporters, Golgi, and a mitochondrion-derived organelle (amoebae only). These results suggest that most of the organelles of higher eukaryotes were present in the common ancestor of all eukaryotes, and so dispute the notion of transitional eukaryotic forms. In addition, phylogenetic studies suggest many of the genes encoding the fermentation enzymes of amoebae and giardia derive from prokaryotes by lateral gene transfer (LGT). While LGT has recently been shown to be an important determinant of prokaryotic evolution, this is the first time that LGT has been shown to be an important determinant of eukaryotic evolution. Further, amoebae contain cyst wall-associated lectins, which resemble, but are distinct from lectins in the walls of insects (convergent evolution). Giardia have a novel microtubule-associated structure which tethers together pairs of nuclei during cell division. It appears then that amoebae and giardia tell us less about the origins of eukaryotes and more about the origins of eukaryotic diversity.

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

    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. PMID:17901334

  2. Reconstruction of Sugar Metabolic Pathways of Giardia lamblia

    Jian Han

    2012-01-01

    Full Text Available Giardia lamblia is an “important” pathogen of humans, but as a diplomonad excavate it is evolutionarily distant from other eukaryotes and relatively little is known about its core metabolic pathways. KEGG, the widely referenced site for providing information of metabolism, does not yet include many enzymes from Giardia species. Here we identify Giardia’s core sugar metabolism using standard bioinformatic approaches. By comparing Giardia proteomes with known enzymes from other species, we have identified enzymes in the glycolysis pathway, as well as some enzymes involved in the TCA cycle and oxidative phosphorylation. However, the majority of enzymes from the latter two pathways were not identifiable, indicating the likely absence of these functionalities. We have also found enzymes from the Giardia glycolysis pathway that appear more similar to those from bacteria. Because these enzymes are different from those found in mammals, the host organisms for Giardia, we raise the possibility that these bacteria-like enzymes could be novel drug targets for treating Giardia infections.

  3. Viability and fate of Cryptosporidium parvum and Giardia lamblia in tubular anaerobic digesters.

    Kinyua, Maureen N; Trimmer, John; Izurieta, Ricardo; Cunningham, Jeffrey; Ergas, Sarina J

    2016-06-01

    In many developing countries where pathogenic diseases of animal waste origin, such as giardiasis and cryptosporidiosis, are often prevalent, facilities are limited to treat livestock waste. However, household-scale anaerobic digesters are currently being promoted for bioenergy production from livestock manure. Since the effluent is often used as a fertilizer for food crops, it is critical to understand the effect of environmental conditions within household-scale digesters on the viability of Cryptosporidium parvum oocysts and Giardia lamblia cysts. In this study, key environmental parameters affecting (oo)cyst inactivation were measured in four tubular anaerobic digesters, which are a type of household-scale digester promoted for treatment of swine waste in rural Costa Rica. Interviews and participant observations were used to understand digester operation and maintenance procedures. Ambient temperatures (21-24°C), near-neutral pH, total ammonia nitrogen (TAN) concentrations<250mg/L and hydraulic retention times (HRTs) between 23 and 180days were observed. Laboratory (oo)cysts inactivation studies were performed in bench-scale digesters, which were maintained under conditions similar to those observed in the field. Apparent first-order inactivation rate coefficients for Giardia lamblia and Cryptosporidium parvum were 0.155±0.041 and 0.054±0.006day(-1), respectively. Temperature and volatile fatty acids were the main factors contributing to Cryptosporidium parvum and Giardia lamblia inactivation. A mathematical model was developed that predicts the concentration of (oo)cysts in the liquid effluent of tubular digesters like those observed in Costa Rica. A mathematical model was developed that predicts the concentration of (oo)cysts in the liquid effluent of tubular digesters like those observed in Costa Rica. Two dimensionless groups can be used to predict the performance of the digesters for inactivating pathogens; both dimensionless groups depend upon the

  4. A sphingolipid inhibitor induces a cytokinesis arrest and blocks stage differentiation in Giardia lamblia.

    Sonda, Sabrina; Stefanic, Sasa; Hehl, Adrian B

    2008-02-01

    Sphingolipid biosynthesis pathways have recently emerged as a promising target for therapeutic intervention against pathogens, including parasites. A key step in the synthesis of complex sphingolipids is the glucosylation of ceramide, mediated by glucosylceramide (GlcCer) synthase, whose activity can be inhibited by PPMP (1-phenyl-2-palmitoylamino-3-morpholino-1-propanol). In this study, we investigated whether PPMP inhibits the proliferation and differentiation of the pathogenic parasite Giardia lamblia, the major cause of parasite-induced diarrhea worldwide. PPMP was found to block in vitro parasite replication in a dose-dependent manner, with a 50% inhibitory concentration of 3.5 muM. The inhibition of parasite replication was irreversible at 10 muM PPMP, a concentration that did not affect mammalian cell metabolism. Importantly, PPMP inhibited the completion of cell division at a specific stage in late cytokinesis. Microscopic analysis of cells incubated with PPMP revealed the aberrant accumulation of cellular membranes belonging to the endoplasmic reticulum network in the caudal area of the parasites. Finally, PPMP induced a 90% reduction in G. lamblia differentiation into cysts, the parasite stage responsible for the transmission of the disease. These results show that PPMP is a powerful inhibitor of G. lamblia in vitro and that as-yet-uncharacterized sphingolipid biosynthetic pathways are potential targets for the development of anti-G. lamblia agents. PMID:18086854

  5. T-Cell-Dependent Control of Acute Giardia lamblia Infections in Mice

    Singer, Steven M.; Nash, Theodore 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 t...

  6. The Study of the Multilayer Filtration Process Efficiency on Giardia lamblia Elimination in Isfahan Water Treatment Plant

    Zahra Mosaviyan

    2014-04-01

    Full Text Available Introduction: Giardia lamblia is a waterborne highly infectious protozoan parasite capable of causing gastrointestinal illness. The multilayer filtration is used in many applications such as turbidity removes from surface waters and Bacteria, Viruses and protozoan removes. This study was investigated in full-scale the efficiency of filtration process during water treatment that remove Giardia cyst in water at Isfahan province. Materials and methods: We used Information Collection Rule method (ICR. In this method the polypropylene yarn-wound cartridge filter for isolation of these parasites was examined and followed by elution, sample concentration, flotation by percoll-sucrose solution and immunofluorescence antibody (IFA staining to recognize them. Results: Result showed that three layer filtration had a maximum 2.3 log10 for remove Giardia cyst. Cysts removal in water filtration is likely to be comparable to the efficiency of turbidity. Efficiency removal was 99.5% for Giardia and 92.7% for turbidity in filtration stage. We detected 0.2 cyst per 100 liter and per 100 liter in filtered water. This observation is according to U.S.EPA standards. The number of cysts were more in high pH samples. Discussion and conclusion: Analysis of physical processes of treatment water in Isfahan plant configurations showed that granular filters (include sand, anthracite and garnet filter were more likely to have effluence in removal cysts than dual filters.

  7. Flagellar generated flow mediates attachment of Giardia Lamblia

    Picou, Theodore; Polackwich, Jamie; Burrola Gabilondo, Beatriz; McAllister, Ryan; Powers, Tom; Elmendorf, Heidi; Urbach, Jeff

    2011-11-01

    Giardia lamblia is a protozoan parasite responsible for widespread diarrheal disease in humans and animals worldwide. Attachment to the host intestinal mucosa and resistance to peristalsis is necessary for establishing infection, but the physical basis for this attachment is poorly understood. We report results from confocal fluorescence microscopy that demonstrate that the regular beating of the posterior flagella generate a flow through the ventral disk, a suction-cup shaped structure that is against the substrate during attachment. Finite element simulations show that the negative pressure generated by the flow is consistent with the measured force of attachement between the parasite and its substrate.

  8. Epigenetic mechanisms regulate stage differentiation in the minimized protozoan Giardia lamblia.

    Sonda, Sabrina; Morf, Laura; Bottova, Iveta; Baetschmann, Hansruedi; Rehrauer, Hubert; Caflisch, Amedeo; Hakimi, Mohamed-Ali; Hehl, Adrian B

    2010-04-01

    Histone modification is an important mechanism regulating both gene expression and the establishment and maintenance of cellular phenotypes during development. Regulation of histone acetylation via histone acetylases and deacetylases (HDACs) appears to be particularly crucial in determining gene expression patterns. In this study we explored the effect of HDAC inhibition on the life cycle of the human pathogen Giardia lamblia, a highly reduced parasitic protozoan characterized by minimized cellular processes. We found that the HDAC inhibitor FR235222 increased the level of histone acetylation and induced transcriptional regulation of approximately 2% of genes in proliferating and encysting parasites. In addition, our analyses showed that the levels of histone acetylation decreased during differentiation into cysts, the infective stage of the parasite. Importantly, FR235222 treatment during encystation reversed this histone hypo-acetylation and potently blocked the formation of cysts. These results provide the first direct evidence for epigenetic regulation of gene expression in this simple eukaryote. This suggests that regulation of histone acetylation is involved in the control of Giardia stage differentiation, and identifies epigenetic mechanisms as a promising target to prevent Giardia transmission. PMID:20132448

  9. Giardia lamblia infection in patients with irritable bowel syndrome and dyspepsia: A prospective study

    Barbara Grazioli; Francesco Luzza; Giovanni Matera; Costanza Laratta; Giuseppina Schipani; Giovanni Guarnieri; Ester Spiniello; Maria Imeneo; Andrea Amorosi; Alfredo Focà

    2006-01-01

    AIM: To evaluate the prevalence of Giardia lamblia (G.lamblia) infection in patients with irritable bowel syndrome (IBS) and dyspepsia and to establish which is the most accurate test to diagnose the infection in this setting.METHODS: One hundred and thirty-seven patients who consecutively attended the Outpatient Gastroenterology Clinic for the first time between January 2002 and December 2003 due to symptoms of IBS and/or dyspepsia were recruited. All patients underwent clinical evaluation,first-step haematology and chemistry tests, serologic assays for celiac disease, lactose-H2 breath test, abdominal ultrasonography, and esophagogastroduodenoscopy.Helicobacter pylori status was evaluated. In patients with symptoms of IBS older than 45 years, colonoscopy was also performed. In all patients, duodenal biopsies and stool samples were examined for trophozoites and cysts of G.lamblia by several methods.RESULTS: G. lamblia was identified in 9 patients. The following diagnoses were also made: IBS (100/137, 73%), functional dyspepsia (62/137, 45%), organic dyspepsia (33/137, 24%), and lactose intolerance (75/137, 55%). A significant association was found between giardiasis and Hpylori infection (x2=6.632,OR= 12.4, CI= 1.5-68.1). There were no symptoms that reliably allowed the recognition of giardiasis.Direct search of the parasite in duodenal biopsy and stool sample examinations gave concordant results in all cases while histological examination of duodenal biopsies displayed a low sensitivity (e.g., 22.2%).CONCLUSION: In this consecutive series, diagnosis of G. lamblia infection accounted for 6.5% of patients with IBS and dyspepsia. Duodenal biopsies for diagnosis of giardiasis may be unnecessary if stool sample examination is performed.

  10. Short Communication—The detection of nuclear matrix in most primitive presentexisting eukaryote,Giardia lamblia

    DAIJIALING; JINGYANLI; 等

    1995-01-01

    The nuclear matrix of diplomonad Giardia lamblia was detected for the first time with DGD embedmentsectioning-embedment free electron microscopy after a series of specific extractions.The result showed that archaezoa Giardia Lamblia already possessed nuclear matrix within its two nuclei.The finest fibrils of the nuclear matrix of Giardia lamblia were measured to be about 11 to 13 nm in thickness.However,the nuclear lamina and nucleolus have never been observed.These results seem to suggest that nuclear matrix is an indispensable intranuclear structural component even in the primitive nucleus.

  11. Sensitive and rapid detection of Giardia lamblia infection in pet dogs using loop-mediated isothermal amplification.

    Li, Jie; Wang, Peiyuan; Zhang, Aiguo; Zhang, Ping; Alsarakibi, Muhamd; Li, Guoqing

    2013-04-01

    Giardia lamblia is recognized as one of the most prevalent parasites in dogs. The present study aimed to establish a loop-mediated isothermal amplification (LAMP) assay for rapid and specific detection of G. lamblia from dogs. The fecal samples were collected and prepared for microscopic analysis, and then the genomic DNA was extracted directly from purified cysts. The concentration of DNA samples of G. lamblia were diluted by 10-fold serially ranging from 10(-1) to 10(-5) ng/µl for LAMP and PCR assays. The LAMP assay allows the amplification to be finished within 60 min under isothermal conditions of 63℃ by employing 6 oligonucleotide primers designed based on G. lamblia elongation factor 1 alpha (EF1α) gene sequence. Our tests showed that the specific amplification products were obtained only with G. lamblia, while no amplification products were detected with DNA of other related protozoans. Sensitivity evaluation indicated that the LAMP assay was sensitive 10 times more than PCR. It is concluded that LAMP is a rapid, highly sensitive and specific DNA amplification technique for detection of G. lamblia, which has implications for effective control and prevention of giardiasis. PMID:23710094

  12. A Homogenous Luminescence Assay Reveals Novel Inhibitors for Giardia Lamblia Carbamate Kinase

    Chen, Catherine Z.; Southall, Noel; Galkin, Andrey; Lim, Kap; Juan J. Marugan; Kulakova, Liudmila; Shinn, Paul; van Leer, Danielle; Zheng, Wei; Herzberg, Osnat

    2012-01-01

    The human pathogen Giardia lamblia is an anaerobic protozoan parasite that causes giardiasis, one of the most common diarrheal diseases worldwide. Although several drugs are available for the treatment of giardisis, resistance to these drugs has been reported and is likely to increase. The Giardia carbamate kinase (glCK) plays an essential role in Giardia metabolism and has no homologs in humans, making it an attractive candidate for anti-Giardia drug development. We have developed a luminesc...

  13. Detection of Giardia lamblia Antigens in Human Fecal Specimens by a Solid-Phase Qualitative Immunochromatographic Assay▿

    Garcia, Lynne S.; Garcia, John Paul

    2006-01-01

    The SIMPLE-READ Giardia rapid assay (Medical Chemical Corporation) is a solid-phase qualitative immunochromatographic assay that detects Giardia lamblia in aqueous extracts of human fecal specimens. Testing 106 Giardia-positive and 104 Giardia-negative stool specimens yielded a sensitivity of 97.2% and a specificity of 100% for the SIMPLE-READ Giardia rapid assay.

  14. Detection of anti-Giardia lamblia serum antibody among children of day care centers Detecção de anticorpos séricos anti-Giardia lamblia em crianças de creches

    Semíramis Guimarães

    2002-02-01

    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.OBJETIVOS: Detectar anticorpos séricos anti-Giardia lamblia entre crianças atendidas em creches e estimar a freqüência de infecção por Giardia lamblia em área endêmica. MÉTODOS: Foram coletadas três amostras de fezes de cada uma das 147 crianças de três creches da rede municipal de Botucatu, SP, com idade variando de 0 a 6 anos, e as amostras foram processadas pelos métodos de sedimentação espontânea e flutuação pelo sulfato de zinco. Amostras de sangue foram obtidas da polpa digital, coletadas em papel de filtro e testadas pelos métodos de imunofluorescência indireta (IFI e de reação imunoenzimática (Elisa para pesquisa de IgG anti-Giardia. RESULTADOS E CONCLUSÕES: De um total de 147 crianças, 93 (63,3% apresentaram cistos de Giardia nas fezes. Dos 147 eluatos testados, 93 (63,3% e 100 (68% foram positivos para Giardia em IFI e em Elisa, respectivamente. A sensibilidade de IFI foi de 82% e de Elisa, 72%. Contudo, Elisa foi menos específica (39% do que IFI (70

  15. Infectious causation of chronic disease: Examining the relationship between Giardia lamblia infection and irritable bowel syndrome

    Alice S Penrose; Eden V Wells; Allison E Aiello

    2007-01-01

    AIM: To evaluate whether a higher prevalence of Giardia lamblia infection is associated with an increase in irritable bowel syndrome (IBS) prescriptions at the county level in Michigan.METHODS: The Michigan Disease Surveillance System (MDSS) was used to ascertain both the numbers of Giardia lamblia infections as well as the total number of foodborne illnesses per population by county in Michigan during 2005. This was compared with Blue Cross Blue Shield (BCBS) of Michigan numbers of drug prescriptions for IBS per one thousand members per county in 2005.These data were also analyzed for associations with per capita income by county and the number of refugees entering each county in 2005.RESULTS: There were a total of 786 confirmed cases of Giardia lamblia reported to MDSS in 2005. During the same time period, the number of prescriptions for IBS varied from 0.5 per 1000 members up to 6.0 per 1000members per month. There was no trend towards higher numbers of IBS prescriptions in the counties with more Giardia lamblia infections. Per capita income was not associated with either IBS prescriptions or Giardiasis.There was a significant linear association between the number of refugees entering each county, and the number of Giardia lamblia cases per 100 000 population.CONCLUSION: In this ecological study, there was no association found between BCBS prescriptions for IBS and Giardia lamblia infections in Michigan counties. Our findings may have been influenced by the disparate number of refugees admitted per county.

  16. Proteomic analysis of the ventral disc of Giardia lamblia

    Lourenço Daniela

    2012-01-01

    Full Text Available Abstract Background Giardia lamblia is a multiflagellated protozoan that inhabits the small intestine of vertebrates, causing giardiasis. To colonize the small intestine, the trophozoites form of the parasite remains attached to intestinal epithelial cells by means of cytoskeletal elements that form a structure known as the ventral disc. Previous studies have shown that the ventral disc is made of tubulin and giardins. Results To obtain further information on the composition of the ventral disc, we developed a new protocol and evaluated the purity of the isolation by transmission electron microscopy. Using 1D- and 2D-PAGE and mass spectrometry, we identified proteins with functions associated with the disc. In addition to finding tubulin and giardin, proteins known to be associated with the ventral disc, we also identified proteins annotated in the Giardia genome, but whose function was previously unknown. Conclusions The isolation of the ventral disc shown in this work, compared to previously published protocols, proved to be more efficient. Proteomic analysis showed the presence of several proteins whose further characterization may help in the elucidation of the mechanisms involved in the attachment of the protozoan to epithelial cells.

  17. Evolution of Eukaryotic Transcription: Insights From the Genome of Giardia lamblia

    Best, Aaron A; Morrison, Hilary G; McArthur, Andrew G.; Sogin, Mitchell L.; Olsen, Gary J.

    2004-01-01

    The Giardia lamblia genome sequencing project affords us a unique opportunity to conduct comparative analyses of core cellular systems between early and late-diverging eukaryotes on a genome-wide scale. We report a survey to identify canonical transcription components in Giardia, focusing on RNA polymerase (RNAP) subunits and transcription-initiation factors. Our survey revealed that Giardia contains homologs to 21 of the 28 polypeptides comprising eukaryal RNAPI, RNAPII, and RNAPIII; six of ...

  18. Chromosome sequence maps of the assemblage A Giardia lamblia isolate WB

    Upcroft, Jacqui A.; Krauer, Kenia G.; Upcroft, Peter

    2010-01-01

    Two genotypes, assemblage A and B, of the pathogenic, gut protozoan parasite Giardia lamblia infect humans. Symptoms of infection range from asymptomatic to chronic diarrhea. Giardia chromosomes have long been characterized but not until the publication of the first Giardia genome sequence was chromosome mapping work, commenced nearly two decades ago, completed. Initial mapping studies identified and ordered Not I chromosome segments (summating to 1.8 Mb) of the estimated 2 Mb chromosome 3. T...

  19. Development of functional gastrointestinal disorders after Giardia lamblia infection

    Hanevik Kurt; Dizdar Vernesa; Langeland Nina; Hausken Trygve

    2009-01-01

    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 month...

  20. Attachment of Giardia lamblia trophozoites to a cultured human intestinal cell line.

    Katelaris, P H; Naeem, A; Farthing, M J

    1995-01-01

    Attachment of Giardia lamblia trophozoites to enterocytes is essential for colonisation of the small intestine and is considered a prerequisite for giardia induced enterocyte damage. The precise mechanisms involved are still being debated and some earlier work has been performed in models of uncertain biological relevance. In this study, co-incubation of giardia with enterocyte-like differentiated Caco-2 cells was used as a model to study the influence of physical and chemical factors on atta...

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

    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.

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

    Hehl, Adrian B; Regos, Attila; Schraner, Elisabeth; Schneider, André

    2007-01-01

    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. PMID:17534438

  3. Occurrence of Cryptosporidium oocysts and Giardia cysts in effluent from sewage treatment plant from eastern Poland.

    Sroka, Jacek; Stojecki, Krzysztof; Zdybel, Jolanta; Karamon, Jacek; Cencek, Tomasz; Dutkiewicz, Jacek

    2013-01-01

    Cryptosporidium spp. and Giardia lamblia (synonyms: Giardia duodenalis, Giardia intestinalis) are emerging protozoa causing disease in humans and animals worldwide. These parasites can pose a serious threat to immunocompromised people, for whom the symptoms are more severe and may include abdominal pain, watery diarrhoea, nausea, headaches, malaise, and fever. One of the sources of these parasites can be treated wastewater from wastewater treatment plants (WTPs). Samples of treated wastewater (effluent), each of 10 L volume, were collected from 13 municipal WTPs located in eastern Poland. Cryptosporidium oocysts and Giardia cysts were separated by the immunomagnetic method. The presence and/or concentration of protozoan (oo)cysts in effluent samples were determined by direct immunofluorescent microscopy, nested PCR and Real Time PCR. Viability of (oo)cysts was determined by double-staining with the use of Live/Dead BacLight kit (Invitrogen). Cryptosporidium spp. oocysts were detected in 8 WTPs (61.5%) and Giardia spp. cysts in 11 WTPs (84.6%) by microscopic analysis. Both pathogens were detected in samples from 7 WTPs. Median concentrations of Cryptosporidium and Giardia (oo)cysts in 13 examined samples were 2.2/L and 6.6/L, respectively, while mean concentrations were 28.5/L and 113.6/L, respectively. In positive samples, Cryptosporidium oocysts concentrations ranged from 0.4 - 154.1 oocysts per litre, and Giardia cysts concentrations ranged from 0.7 - 660 cysts per litre. By nested PCR, Giardia DNA was detected in 4 samples of the 13 examined, (30.8%) while Cryptosporidium DNA was never detected. In Real Time PCR, positive results for Giardia were obtained in 5 samples (38.5%) and in none of the samples for Cryptosporidium, with the exception of one equivocal result. Viable (oo)cysts of Cryptosporidium and Giardia were detected in 3 out of 4 samples examined, in the ranges of 12.5 - 60% and 50 - 100% of total (oo)cysts, respectively. In view of our preliminary

  4. α1-giardin based live heterologous vaccine protects against Giardia lamblia infection in a murine model

    Jenikova, Gabriela; Hruz, Petr; Andersson, Karl M.; Tejman-Yarden, Noa; Ferreira, Patricia C. D.; Andersen, Yolanda S.; Davids, Barbara J.; Gillin, Frances D.; Svärd, Staffan G; Curtiss, Roy; Eckmann, Lars

    2011-01-01

    Giardia lamblia is a leading protozoan cause of diarrheal disease worldwide, yet preventive medical strategies are not available. A crude veterinary vaccine has been licensed for cats and dogs, but no defined human vaccine is available. We tested the vaccine potential of three conserved antigens previously identified in human and murine giardiasis, α1-giardin, α-enolase, and ornithine carbamoyl transferase, in a murine model of G. lamblia infection. Live recombinant attenuated Salmonella ente...

  5. Nitroimidazole drugs vary in their mode of action in the human parasite Giardia lamblia

    Leitsch, David; Schlosser, Sarah; Burgess, Anita; Duchêne, Michael

    2012-01-01

    Giardia lamblia (syn. duodenalis, intestinalis) is a globally occurring micro-aerophilic human parasite that causes gastrointestinal disease. Standard treatment of G. lamblia infections is based on the 5-nitroimidazole drugs metronidazole and tinidazole. In two other micro-aerophilic parasites, Entamoeba histolytica and Trichomonas vaginalis, 5-nitroimidazole drugs bind to proteins involved in the thioredoxin-mediated redox network and disrupt the redox equilibrium by inhibiting thioredoxin r...

  6. Monoclonal antibody-based enzyme immunoassay for Giardia lamblia antigen in human stool.

    Stibbs, H H

    1989-01-01

    A visually readable monoclonal antibody-based antigen-capture enzyme immunoassay for the detection of Giardia lamblia antigen in human stool specimens was developed and found to be 97% (30 of 31 stool specimens) sensitive for formalinized stools and 82% (49 of 60 stool specimens) sensitive for unfixed stool specimens by visual reading. The storage of specimens in 10% Formalin resulted in increased absorbance in 20 of 26 G. lamblia-positive specimens tested as both formalinized and unfixed spe...

  7. The single dynamin family protein in the primitive protozoan Giardia lamblia is essential for stage conversion and endocytic transport.

    Gaechter, Verena; Schraner, Elisabeth; Wild, Peter; Hehl, Adrian B

    2008-01-01

    Dynamins are universally conserved large guanosine triphosphatases, which function as mechanoenzymes in membrane scission. The primitive protozoan Giardia lamblia has a single dynamin-related protein (GlDRP) with an unusual domain structure. Giardia lacks a Golgi apparatus but generates transient Golgi-like delay compartments dubbed encystation-specific vesicles (ESVs), which serve to accumulate and mature cyst wall proteins during differentiation to infectious cyst forms. Here, we analyze the function of GlDRP during growth and encystation and demonstrate that it relocalizes from peripheral endosomal-lysosomal compartments to nascent ESVs. We show that GlDRP is necessary for secretion of the cyst wall material and ESV homeostasis. Expression of a dominant-negative GlDRP variant does not interfere with ESV formation but blocks cyst formation completely prior to regulated exocytosis. GlDRP colocalizes with clathrin at the cell periphery and is necessary for endocytosis of surface proteins to endosomal-lysosomal organelles in trophozoites. Electron microscopy and live cell imaging reveal gross morphological changes as well as functional impairment of the endocytic system in cells expressing the dominant-negative GlDRP. Thus, giardial DRP plays a key role in two distinct trafficking pathways and in organelle homeostasis, both essential functions for the proliferation of the parasite in the gut and its transmission to a new host. PMID:17892527

  8. The Cre/loxP system in Giardia lamblia: genetic manipulations in a binucleate tetraploid protozoan.

    Wampfler, Petra B; Faso, Carmen; Hehl, Adrian B

    2014-07-01

    The bacteriophage-derived Cre/loxP system is a valuable tool that has revolutionised genetic and cell biological research in many organisms. We implemented this system in the intestinal parasite Giardia lamblia, an evolutionarily diverged protozoan whose binucleate and tetraploid genome organisation severely limits the application of reverse genetic approaches. We show that Cre-recombinase is functionally expressed in G. lamblia and demonstrate "recycling" of selectable markers. Providing the means for more complex and versatile genetic modifications, this technique massively increases the scope of functional investigations in G. lamblia and other protozoa with similar limitations with respect to genetic manipulation. PMID:24747534

  9. High-Throughput Giardia lamblia Viability Assay Using Bioluminescent ATP Content Measurements▿

    Chen, Catherine Z.; Kulakova, Liudmila; Southall, Noel; Juan J. Marugan; Galkin, Andrey; Austin, Christopher P.; Herzberg, Osnat; Zheng, Wei

    2010-01-01

    The human pathogen Giardia lamblia is an anaerobic protozoan parasite that causes giardiasis, one of the most common diarrheal diseases worldwide. Although several drugs are available for the treatment of giardiasis, drug resistance has been reported and is likely to increase, and recurrent infections are common. The search for new drugs that can overcome the drug-resistant strains of Giardia is an unmet medical need. New drug screen methods can facilitate the drug discovery process and aid w...

  10. Molecular Analysis of Household Transmission of Giardia lamblia in a Region of High Endemicity in Peru

    Cooper, Margarethe A.; Sterling, Charles R; Gilman, Robert H.; Cama, Vitaliano; Ortega, Ynes; Adam, Rodney D.

    2010-01-01

    Background. Giardia lamblia is ubiquitous in multiple communities of nonindustrialized nations. Genotypes A1, A2, and B (Nash groups 1, 2, and 3, respectively) are found in humans, whereas genotypes C and D are typically found in dogs. However, genotypes A and B have occasionally been identified in dogs.

  11. CLONING AND CHARACTERIZATION OF CDNA ENCODING GIARDIA LAMBLIA d-GIARDIN

    A cDNA coding for d-giardin was cloned from Giardia lamblia trophozoites in order to localize the protein and study its function in mediating surface attachment. Recombinant d-giardin antigen was produced in Escherichia coli as a poly-histidine fusion protein and was purified by affinity chromatogr...

  12. MATRIX ASSISTED LASER DESORPTION/IONIZATION TIME OF FLIGHT MASS SPECTROMETRY BASED ANALYSIS OF GIARDIA LAMBLIA

    Giardia lamblia is a zoonotic protozoan parasite that is a leading cause of drinking water related gastro-intestinal disease outbreaks worldwide. Due to the genotypic complexity and high prevalence of this parasite in the environment, numerous research studies are being done to ...

  13. An integrated microfludic device for culturing and screening of Giardia lamblia.

    Zheng, Guo-Xia; Zhang, Xue-Mei; Yang, Yu-Suo; Zeng, Shu-Rui; Wei, Jun-Feng; Wang, Yun-Hua; Li, Ya-Jie

    2014-02-01

    In vitro culturing of trophozoites was important for research of Giardia lamblia (G. lamblia), especially in discovery of anti-Giardia agents. The current culture methods mainly suffer from lab-intension or the obstacle in standardizing the gas condition. Thus, it could benefit from a more streamlined and integrated approach. Microfluidics offers a way to accomplish this goal. Here we presented an integrated microfluidic device for culturing and screening of G. lamblia. The device consisted of a polydimethylsiloxane (PDMS) microchip with an aerobic culture system. In the microchip, the functionality of integrated concentration gradient generator (CGG) with micro-scale cell culture enables dose-response experiment to be performed in a simple and reagent-saving way. The diffusion-based culture chambers allowed growing G. lamblia at the in vivo like environment. It notable that the highly air permeable material of parallel chambers maintain uniform anaerobic environment in different chambers easily. Using this device, G. lamblia were successfully cultured and stressed on-chip. In all cases, a dose-related inhibitory response was detected. The application of this device for these purposes represents the first step in developing a completely integrated microfluidic platform for high-throughput screening and might be expanded to other assays based on in vitro culture of G. lamblia with further tests. PMID:24316463

  14. Identification of an immunogenic protein of Giardia lamblia using monoclonal antibodies generated from infected mice

    Jael Quintero

    2013-08-01

    Full Text Available The humoral immune response plays an important role in the clearance of Giardia lamblia. However, our knowledge about the specific antigens of G. lamblia that induce a protective immune response is limited. The purpose of this study was to identify and characterise the immunogenic proteins of G. lamblia in a mouse model. We generated monoclonal antibodies (moAbs specific to G. lamblia (1B10, 2C9.D11, 3C10.E5, 3D10, 5G8.B5, 5F4, 4C7, 3C5 and 3C6 by fusing splenocytes derived from infected mice. Most of these moAbs recognised a band of ± 71 kDa (5G8 protein and this protein was also recognised by serum from the infected mice. We found that the moAbs recognised conformational epitopes of the 5G8 protein and that this antigen is expressed on the cell surface and inside trophozoites. Additionally, antibodies specific to the 5G8 protein induced strong agglutination (> 70-90% of trophozoites. We have thus identified a highly immunogenic antigen of G. lamblia that is recognised by the immune system of infected mice. In summary, this study describes the identification and partial characterisation of an immunogenic protein of G. lamblia. Additionally, we generated a panel of moAbs specific for this protein that will be useful for the biochemical and immunological characterisation of this immunologically interesting Giardia molecule.

  15. Prevalence of Giardia lamblia in Different Water Sources of District Nowshehra, Khyber Pakhtunkhwa Pakistan.

    khan, Shaukat Ali; Ayaz, Sultan; Khan, Sanaullah; Anees, Muhammad; Khan, Amir Muhammad; Khan, Imran

    2012-12-01

    Giardia lamblia is a cosmopolitan parasite that occurs worldwide and generally effects gastrointestinal tract. Water played a media for transmission of Giardia to different hosts. A total of 300 water samples were examined from different water sources, i.e. tap, open well, bore well and drain waters and DNA was extracted by trizol method through prescribed protocol. DNA was amplified through PCR. The overall prevalence of G. lamblia was 27.66% (83/300). Among these 2.5% (1/40) in bore well water, 29% (29/100) open well, 18.83% (11/60) tap water and 42% (42/100) drain water. It is concluded from the study that Giardia is frequently found in all water sources and is the main cause of ill health.

  16. Human Memory CD4+ T Cell Immune Responses against Giardia lamblia.

    Saghaug, Christina Skår; Sørnes, Steinar; Peirasmaki, Dimitra; Svärd, Staffan; Langeland, Nina; Hanevik, Kurt

    2016-01-01

    The intestinal protozoan parasite Giardia lamblia may cause severe prolonged diarrheal disease or pass unnoticed as an asymptomatic infection. T cells seem to play an important role in the immune response to Giardia infection, and memory responses may last years. Recently, TH17 responses have been found in three animal studies of Giardia infection. The aim of this study was to characterize the human CD4(+) T cell responses to Giardia. Peripheral blood mononuclear cells (PBMCs) were obtained from 21 returning travelers with recent or ongoing giardiasis and 12 low-risk healthy controls and stimulated in vitro with Giardia lamblia proteins. Production of tumor necrosis factor alpha (TNF-α), gamma interferon, interleukin-17A (IL-17A), IL-10, and IL-4 was measured in CD4(+) effector memory (EM) T cells after 24 h by flow cytometry. After 6 days of culture, activation and proliferation were measured by flow cytometry, while an array of inflammatory cytokine levels in supernatants were measured with multiplex assays. We found the number of IL-17A-producing CD4(+) EM T cells, as well as that of cells simultaneously producing both IL-17A and TNF-α, to be significantly elevated in the Giardia-exposed individuals after 24 h of antigen stimulation. In supernatants of PBMCs stimulated with Giardia antigens for 6 days, we found inflammation-associated cytokines, including 1L-17A, as well as CD4(+) T cell activation and proliferation, to be significantly elevated in the Giardia-exposed individuals. We conclude that symptomatic Giardia infection in humans induces a CD4(+) EM T cell response of which IL-17A production seems to be an important component. PMID:26376930

  17. Inducible nitric oxide synthase in duodenum of children with Giardia lamblia infection.

    Agnieszka Kolasa

    2010-08-01

    Full Text Available The investigation were performed on children with Giardia lamblia infection, diagnosed on the basis of positive stool tests for Giardia antigen (Elisa or by microscopical detection of trophozoites in duodenal fluid. In duodenal biopsies morphological studies and immunohistochemical reaction for inducible nitric oxide synthase (iNOS were performed. The control group was made up of duodenal tissue of children with excluded giardiasis and inflammation of the upper part of gastrointestinal tract. The duodenal biopsies from children without Giardia lamblia infection were found to have a high immunoreactivity for iNOS in enterocytes, the cells of intestinal crypts, endothelial cells of vessels and connective tissue cells of lamina propria. In children with giardiasis: in some biopsies the expression of iNOS was as high as in control group, in others was weaker detectable and the shortening of intestinal villi was seen. There were also duodenal biopsies with the lack of immunoreactivity for iNOS, with shorter villi and a large amount of mucus in the intestinal epithelium. Beside of goblet cells, also enterocytes were loaded with mucus. The pathological changes may cause malabsorption and also may have a negative influence on the defense of the intestinal wall against Giardia lamblia infection. The different morphological and immunohistochemical results in the duodenum of children with giardiasis can elucidate a variety of clinical symptoms from asymptomatic to severe infection.

  18. 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

    N. Abreu Acosta

    2002-06-01

    Full Text Available 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 habitats. These protozoan investigation and detection have acquired importance in the last years due to their dispersion forms, which show resistance to the habitual treatments of potabilization and purification, and their classification as emerging pathogens which are the causative agents of important hydrical transmission outbreaks.In our work, Giardia lamblia cyst and Cryptosporidium spp. oocyst presence in Santa Cruz de Tenerife treated wastewater which is transported to the South of the island to be reutilised in agriculture. Furthermore, transport, storage and advanced treatment effects against cyst and oocyst concentration throughout the system and relation existence with other bacteriological and physical-chemical parameters, are also investigated.The obtained results demonstrate variable behaviours in cyst and oocyst concentration against applied treatments, and the depurative effect of the long-distance transport which seems to have in treated wastewater.There was not found any relation between cyst and oocyst concentration in treated wastewater and the traditional indicators of faecal contamination.

  19. Neuronal Nitric Oxide Synthase is Necessary for Elimination of Giardia lamblia Infections in Mice1

    Li, Erqiu; Zhou, Ping; Singer, Steven M.

    2006-01-01

    Nitric oxide (NO) produced by inducible nitric oxide synthase (NOS2) is important for control of numerous infections. In vitro, NO inhibits replication and differentiation of the intestinal protozoan parasite Giardia lamblia. However, the role of NO against this parasite has not been tested in vivo. IL-6 deficient mice fail to control Giardia infections and these mice have reduced levels of NOS2 mRNA in the small intestine following infection compared to wild-type mice. However, NOS2 gene-tar...

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

    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.

  1. First genotyping of Giardia lamblia from human and animal feces in Argentina, South America

    Marta C Minvielle; Nora B Molina; Daniela Polverino; Basualdo, Juan A.

    2008-01-01

    The purpose of this study was to investigate the genotypes of Giardia lamblia from human and animal feces and their epidemiological and clinical characteristics in Argentina, South America. Seventy isolates, 60 from humans (adults and children), eight from dogs and two from cows were processed by polymerase chain reaction-restriction fragment length polymorphism. Data corresponding to demographic, socio-cultural and environmental variables and presence/absence of signs/symptoms were collected...

  2. Immunochromatographic Strip-Based Detection of Entamoeba histolytica-E. dispar and Giardia lamblia Coproantigen

    Pillai, Dylan R.; Kain, Kevin C.

    1999-01-01

    BIOSITE Triage was 68.3% sensitive and 100% specific for the detection of Entamoeba histolytica-E. dispar (n = 71) compared to Alexon-Trend’s ProSpecT test (reference standard) using fresh-frozen stool. Neither test is able to distinguish E. histolytica from E. dispar. Triage was 83.3% sensitive and 100% specific compared to microscopy (formalin-ether concentrates and permanent stains) for the detection of Giardia lamblia.

  3. Modified PEHPS Medium as an Alternative for the In Vitro Culture of Giardia lamblia

    Javier Vargas-Villarreal

    2014-01-01

    Full Text Available Commercial culture media present interlot variations in biological activity. We have previously designed a homemade and economic culture medium, PEHPS medium, for the axenic cultivation of Entamoeba histolytica and Trichomonas vaginalis. Trophozoites of amoebae and trichomonads grow well in this medium. Furthermore, the medium is stable for several months when stored frozen or refrigerated. The objective of this work was to modify PEHPS medium to support the in vitro growth of Giardia lamblia. Inocula of 5 × 103 trophozoites/mL of G. lamblia were incubated at 36.5°C in modified PEHPS or TYI-S-33 medium. Then, the growths of the three Giardia strains in both media were compared. The logarithmic growth phase lasted 72 h; the mean yield of the strains ranged from 10.06 to 11.43 × 105Giardia trophozoites/mL, and the range of duplication time in the three strains was from 5.67 to 6.06 in modified PEHPS medium. These growth characteristics were not significantly different from those obtained with TYI-S-33 medium. We conclude that modified PEHPS medium might be used for the axenic cultivation of G. lamblia.

  4. Waterborne Giardia cysts and Cryptosporidium oocysts in the Yukon, Canada.

    Roach, P D; Olson, M. E.; Whitley, G; Wallis, P M

    1993-01-01

    Several outbreaks of waterborne giardiasis have occurred in southern Canada, but nothing has been reported from the Canadian North. The objective of this study was to collect information relevant to waterborne giardiasis and cryptosporidiosis in the Yukon including epidemiological data and analyses of water, sewage, and animal fecal samples. Remote, pristine water samples were found to be contaminated with Giardia cysts (7 of 22 or 32%) but not with Cryptosporidium oocysts. Giardia cysts were...

  5. The Transcriptional Response to Encystation Stimuli in Giardia lamblia Is Restricted to a Small Set of Genes ▿†

    Morf, Laura; Spycher, Cornelia; Rehrauer, Hubert; Fournier, Catharine Aquino; Morrison, Hilary G.; Hehl, Adrian B.

    2010-01-01

    The protozoan parasite Giardia lamblia undergoes stage differentiation in the small intestine of the host to an environmentally resistant and infectious cyst. Encystation involves the secretion of an extracellular matrix comprised of cyst wall proteins (CWPs) and a β(1-3)-GalNAc homopolymer. Upon the induction of encystation, genes coding for CWPs are switched on, and mRNAs coding for a Myb transcription factor and enzymes involved in cyst wall glycan synthesis are upregulated. Encystation in vitro is triggered by several protocols, which call for changes in bile concentrations or availability of lipids, and elevated pH. However, the conditions for induction are not standardized and we predicted significant protocol-specific side effects. This makes reliable identification of encystation factors difficult. Here, we exploited the possibility of inducing encystation with two different protocols, which we show to be equally effective, for a comparative mRNA profile analysis. The standard encystation protocol induced a bipartite transcriptional response with surprisingly minor involvement of stress genes. A comparative analysis revealed a core set of only 18 encystation genes and showed that a majority of genes was indeed upregulated as a side effect of inducing conditions. We also established a Myb binding sequence as a signature motif in encystation promoters, suggesting coordinated regulation of these factors. PMID:20693303

  6. The transcriptional response to encystation stimuli in Giardia lamblia is restricted to a small set of genes.

    Morf, Laura; Spycher, Cornelia; Rehrauer, Hubert; Fournier, Catharine Aquino; Morrison, Hilary G; Hehl, Adrian B

    2010-10-01

    The protozoan parasite Giardia lamblia undergoes stage differentiation in the small intestine of the host to an environmentally resistant and infectious cyst. Encystation involves the secretion of an extracellular matrix comprised of cyst wall proteins (CWPs) and a β(1-3)-GalNAc homopolymer. Upon the induction of encystation, genes coding for CWPs are switched on, and mRNAs coding for a Myb transcription factor and enzymes involved in cyst wall glycan synthesis are upregulated. Encystation in vitro is triggered by several protocols, which call for changes in bile concentrations or availability of lipids, and elevated pH. However, the conditions for induction are not standardized and we predicted significant protocol-specific side effects. This makes reliable identification of encystation factors difficult. Here, we exploited the possibility of inducing encystation with two different protocols, which we show to be equally effective, for a comparative mRNA profile analysis. The standard encystation protocol induced a bipartite transcriptional response with surprisingly minor involvement of stress genes. A comparative analysis revealed a core set of only 18 encystation genes and showed that a majority of genes was indeed upregulated as a side effect of inducing conditions. We also established a Myb binding sequence as a signature motif in encystation promoters, suggesting coordinated regulation of these factors. PMID:20693303

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

    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. PMID:26212101

  8. Sequence analysis and prokaryotic expression of Giardia lamblia α-18 giardin gene.

    Wu, Sheng; Yu, Xingang; Abdullahi, Auwalu Yusuf; Hu, Wei; Pan, Weida; Shi, Xianli; Tan, Liping; Song, Meiran; Li, Guoqing

    2016-03-01

    To study the genetic variation and prokaryotic expression of α18 giardin gene of Giardia lamblia zoonotic assemblage A and host-specific assemblage F, the α18 genes were amplified from G. lamblia assemblages A and F by PCR and sequenced. The PCR product was cloned into the prokaryotic expression vector pET-28a(+) and the positive recombinant plasmid was transformed into Escherichia coli Rosetta (DE3) strain for the expression. The expressed α18 giardin fusion protein was validated by SDS-PAGE and Western blot analysis, and purified by Ni-Agarose resin. The putative sequence of α18 giardin amino acid was analyzed by bioinformatics software. Results showed that the α18 giardin gene was 861 bp in length, encoding 286 amino acids; it was 100% homologous between human-derived and dog-derived G. lamblia assemblage A, but it was 86.8% homologous with G. lamblia assemblage F (cat-derived). Giardin α18 was about 36 kDa in molecular weight, with good reactivity. Prediction based on in silico analyses: it had hydrophobicity, without signal peptide and transmembrane domain, and contained 11 alpha regions, 13 beta sheets, 1 beta turn and 7 random coils in secondary structure. The above information would lay the foundation for research about the subcellular localization and biological function of α18 giardin in G. lamblia. PMID:26656833

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

    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.

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

    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

  11. 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

    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

  12. Glucosylceramide synthesis inhibition affects cell cycle progression, membrane trafficking, and stage differentiation in Giardia lamblia[S

    Štefanić, Saša; Spycher, Cornelia; Morf, Laura; Fabriàs, Gemma; Casas, Josefina; Schraner, Elisabeth; Wild, Peter; Hehl, Adrian B.; Sonda, Sabrina

    2010-01-01

    Synthesis of glucosylceramide via glucosylceramide synthase (GCS) is a crucial event in higher eukaryotes, both for the production of complex glycosphingolipids and for regulating cellular levels of ceramide, a potent antiproliferative second messenger. In this study, we explored the dependence of the early branching eukaryote Giardia lamblia on GCS activity. Biochemical analyses revealed that the parasite has a GCS located in endoplasmic reticulum (ER) membranes that is active in proliferating and encysting trophozoites. Pharmacological inhibition of GCS induced aberrant cell division, characterized by arrest of cytokinesis, incomplete cleavage furrow formation, and consequent block of replication. Importantly, we showed that increased ceramide levels were responsible for the cytokinesis arrest. In addition, GCS inhibition resulted in prominent ultrastructural abnormalities, including accumulation of cytosolic vesicles, enlarged lysosomes, and clathrin disorganization. Moreover, anterograde trafficking of the encystations-specific protein CWP1 was severely compromised and resulted in inhibition of stage differentiation. Our results reveal novel aspects of lipid metabolism in G. lamblia and specifically highlight the vital role of GCS in regulating cell cycle progression, membrane trafficking events, and stage differentiation in this parasite. In addition, we identified ceramide as a potent bioactive molecule, underscoring the universal conservation of ceramide signaling in eukaryotes. PMID:20335568

  13. Development of a Method for Detection of Giardia duodenalis Cysts on Lettuce and for Simultaneous Analysis of Salad Products for the Presence of Giardia Cysts and Cryptosporidium Oocysts▿

    Cook, N.; Nichols, R.A.B.; Wilkinson, N; Paton, C. A.; Barker, K; Smith, H.V.

    2007-01-01

    We report a method for detecting Giardia duodenalis cysts on lettuce, which we subsequently use to examine salad products for the presence of Giardia cysts and Cryptosporidium oocysts. The method is based on four basic steps: extraction of cysts from the foodstuffs, concentration of the extract and separation of the cysts from food materials, staining of the cysts to allow their visualization, and identification of cysts by microscopy. The concentration and separation steps are performed by c...

  14. Effects of the extract and glycoalkaloids of Solanum lycocarpum St. Hill on Giardia lamblia trophozoites

    Gilmarcio Z Martins

    2015-01-01

    Full Text Available Background: Solanum lycocarpum has great importance for food and medicinal traditional use. Recently, it was also evidenced that extracts of S. lycocarpum St. Hill (Solanaceae and its glycoalkaloids, solamargine (Sg and solasonine (Sn, are active against flagellated protozoa. Objective: The aim was to assess the effects of the extract of S. lycocarpum and its glycoalkaloids, Sn, and Sg, on Giardia lamblia trophozoites. Materials and Methods: A crude extract (96% ethanol (EB of fruits of S. lycocarpum was prepared and fractionated by partition with 40% ethanol and n-hexane: Ethyl acetate. Glycoalkaloids, Sn, and Sg were recognized in the ethanol fraction (EF and further isolated by column chromatography. EB, EF, the isolated Sn and Sg and a mixture (1:1 of both glycoalkaloids were tested on cultures of G. lamblia trophozoites and macrophages. Results: EB, EF and glycoalkaloids of S. lycocarpum showed activity against Giardia (95.0 < Inhibitory concentration 50 [IC 50 ] ≤120.3 μg/mL. The mixture of glycoalkaloids (1:1 was more active (IC 50 = 13.23 μg/mL than each one individually, suggesting a synergic effect. Moreover, the mixture is nontoxic to macrophage cells. Conclusion: Results are optimistic concerning the anti-Giardia potential of the mixture Sn + Sg. Further studies, in vitro and in vivo, will be required to consolidate the usefulness of the mixture of Sn + Sg in view of a new therapeutic strategy for giardiasis.

  15. Α1-giardin based live heterologous vaccine protects against Giardia lamblia infection in a murine model.

    Jenikova, Gabriela; Hruz, Petr; Andersson, Mattias K; Tejman-Yarden, Noa; Ferreira, Patricia C D; Andersen, Yolanda S; Davids, Barbara J; Gillin, Frances D; Svärd, Staffan G; Curtiss, Roy; Eckmann, Lars

    2011-11-28

    Giardia lamblia is a leading protozoan cause of diarrheal disease worldwide, yet preventive medical strategies are not available. A crude veterinary vaccine has been licensed for cats and dogs, but no defined human vaccine is available. We tested the vaccine potential of three conserved antigens previously identified in human and murine giardiasis, α1-giardin, α-enolase, and ornithine carbamoyl transferase, in a murine model of G. lamblia infection. Live recombinant attenuated Salmonella enterica Serovar Typhimurium vaccine strains were constructed that stably expressed each antigen, maintained colonization capacity, and sustained total attenuation in the host. Oral administration of the vaccine strains induced antigen-specific serum IgG, particularly IgG(2A), and mucosal IgA for α1-giardin and α-enolase, but not for ornithine carbamoyl transferase. Immunization with the α1-giardin vaccine induced significant protection against subsequent G. lamblia challenge, which was further enhanced by boosting with cholera toxin or sublingual α1-giardin administration. The α-enolase vaccine afforded no protection. Analysis of α1-giardin from divergent assemblage A and B isolates of G. lamblia revealed >97% amino acid sequence conservation and immunological cross-reactivity, further supporting the potential utility of this antigen in vaccine development. Together. These results indicate that α1-giardin is a suitable candidate antigen for a vaccine against giardiasis. PMID:22001876

  16. Physical and chemical characterization of a Giardia lamblia-specific antigen useful in the coprodiagnosis of giardiasis.

    Rosoff, J D; Stibbs, H H

    1986-01-01

    We recently reported the isolation and identification of a Giardia lamblia-specific antigen (GSA 65) that is shed in the stool of giardiasis patients. In the present study, this antigen was affinity purified from sonic extracts of axenically cultured G. lamblia trophozoites and characterized to better understand its biological function and its potential usefulness in the design of coprodiagnostic assays for giardiasis. GSA 65 was resistant to proteolytic digestion with trypsin, chymotrypsin, ...

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

    Wei Hu; Sheng Wu; Xingang Yu; Auwalu Yusuf Abullahi; Meiran Song; Liping Tan; Zhen Wang; Biao Jiang; Guoqing Li

    2015-01-01

    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 w...

  18. Freqüência de Giardia lamblia em cães atendidos em clínicas veterinárias de Porto Alegre, RS, Brasil Frequency of Giardia lamblia in dogs attended by veterinary clinics in Porto Alegre city, RS, Brazil

    Adriane Bartmann

    2004-08-01

    Full Text Available A pesquisa de cistos de Giardia lamblia em fezes de cães oriundos de clínicas veterinárias de Porto Alegre, RS, Brasil, foi realizada pelo método de FAUST et al. (1939. Das 526 amostras analisadas, 38% (198 foram positivas para cistos de G. lamblia, sendo 22% (116 constituídos por animais menores de 11 meses de idade e 16% (82 constituídos por animais com 12 meses ou mais de idade. Houve diferença significativa (pThe method of Faust et al. (1939 was utilized for detection of Giardia lamblia cysts in feces from dogs in Porto Alegre city, Rio Grande Sul State, Brazil. From the 526 analyzed samples 38% (198 showed positive results for the presence of G. lamblia cyst, so 22% (116 belonged to group one, formed by animals that were less than eleven months old; and 16% (82 belonged to group two, formed by animals that were twelve months or older. There was a significant difference (p<0,05 among the two groups checked by the c² test. From the animals researched, 54% (285 were male dogs and from these 20% (104 presented cysts in their feces. From the other 46% (241, which were female dogs, 18% (95 presented positive results for the cysts of G. lamblia in their sample. The c² test applied to these data showed that there was not any significant difference between the results found in female or male dogs of all ages. Based on these results, we can come to the conclusion that 38% of the analyzed dogs showed positive results for the infection of G. lamblia and that the younger animals those aged less than eleven months presented a rate of risk to get infected which is two times bigger than the ones for the animals with 12 months or older, as well as, the fact that the sex of the animals did not present any association to the positive results of infection.

  19. Efecto de un extracto de Petiveria Alliacea Lin sobre el crecimiento de Giardia lamblia in vitro

    Aimée Echevarría; Dinorah Torres Idavoy

    2001-01-01

    Se evaluó el efecto de un extracto fluido elaborado con un menstruo de Petiveria alliacea (anamú) sobre el crecimiento in vitro de Giardia lamblia. Para este ensayo se empleó una cepa aislada en el Instituto de Medicina Tropical "Pedro Kourí", procedente de un paciente infestado. Los cultivos fueron incubados a 37 °C durante 48 h y posteriormente ajustada su concentración a 2 ´105 parásitos por 0,5 mL. Los resultados obtenidos muestran un marcado efecto antigiardiásico, por los altos porcenta...

  20. Mast Cell-Dependent Control of Giardia lamblia Infections in Mice

    Li, Erqiu; Zhou, Ping; Petrin, Ziva; Singer, Steven M.

    2004-01-01

    Mast cells are important for protective immunity to intestinal helminth infections and as mediators of allergic disease. Their role in protozoan infections is less well described. We have therefore analyzed mast cell responses and parasite control in mice infected with the protozoan Giardia lamblia. We also measured immunoglobulin A (IgA) responses to the parasite, as IgA can have a protective role in this model. c-kitw/wv mice failed to make parasite-specific IgA, mount a mast cell response,...

  1. A new-generation 5-nitroimidazole can induce highly metronidazole-resistant Giardia lamblia in vitro

    Dunn, Linda A.; Burgess, Anita G.; Krauer, Kenia G.; Eckmann, Lars; Vanelle, Patrice; Maxime D. Crozet; Gillin, Frances D.; Upcroft, Peter; Upcroft, Jacqueline A.

    2010-01-01

    The 5-nitroimidazole (NI) compound C17, with a side chain carrying a remote phenyl group in the 2-position of the imidazole ring, is at least 14-fold more active against the gut protozoan parasite Giardia lamblia than the 5-NI drug metronidazole (MTR), with a side chain in the 1-position of the imidazole ring, which is the primary drug for the treatment of giardiasis. Over 10 months, lines resistant to C17 were induced in vitro and were at least 12-fold more resistant to C17 than the parent s...

  2. Occurrence of Giardia and Cryptosporidium (oo)cysts in the river water of two recreational areas in Selangor, Malaysia.

    Azman, J; Init, I; Wan Yusoff, W S

    2009-12-01

    This study is the first report on the occurrence of Giardia and Cryptosporidium (oo)cysts in recreational rivers water from Malaysia. It was carried out in water samples at two rivers, 'Sungai Congkak' and 'Sungai Batu', located in Selangor State. The occurrence of both Giardia lamblia and Cryptosporidium parvum (oo)cysts was higher in Sungai Congkak (50% or 15/30 and 10% or 3/30 respectively) than Sungai Batu (16% or 5/30 and 3.3% or 1/30 respectively). The mean density of cysts/L was 0.72 in Sungai Congkak and 0.023 in Sungai Batu, and that of oocysts/L was 0.023 in Sungai Congkak and 0.0033 in Sungai Batu, showing that the occurrence of Giardia was higher and more frequent than Cryptosporidium in both rivers. Sungai Congkak also showed higher faecal coliforms count (ranging from 0.48x10³ to 73x10³ CFU/100 mL) than Sungai Batu (0.41x10³ to 16x10³ CFU/100 mL). On the other hand, the Giardia and Cryptosporidium (oo)cysts and faecal coliforms were more concentrated at the downstream station, followed by midstream and upstream stations which might be due to human factors where settlements and recreation areas were located around and between midstream and downstream stations. The (oo)cysts and faecal coliforms also increased during public holidays due to the significantly higher number of visitors (bathers) compared with the week days. All the parameters (physical, faecal coliforms and rainfall) did not show consistent significant correlation (based on r values of Pearson correlation analysis) with both protozoa, therefore these parameters are not suitable as indicator for the presence of Giardia and Cryptosporidium (oo)cysts in both rivers. PMID:20237443

  3. Clathrin-dependent pathways and the cytoskeleton network are involved in ceramide endocytosis by a parasitic protozoan, Giardia lamblia

    Hernandez, Yunuen; Castillo, Cynthia; Roychowdhury, Sukla; Hehl, Adrian; Aley, Stephen B.; Das, Siddhartha

    2006-01-01

    Although identified as an early-diverged protozoan, Giardia lamblia shares many similarities with higher eukaryotic cells, including an internal membrane system and cytoskeleton, as well as secretory pathways. However, unlike many other eukaryotes, Giardia does not synthesize lipids de novo, but rather depends on exogenous sources for both energy production and organelle or membrane biogenesis. It is not known how lipid molecules are taken up by this parasite and if endocytic pathways are inv...

  4. Modeling Long-Term Host Cell-Giardia lamblia Interactions in an In Vitro Co-Culture System

    Fisher, Bridget S.; Estraño, Carlos E.; Cole, Judith A

    2013-01-01

    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 propri...

  5. A contiguous compartment functions as endoplasmic reticulum and endosome/lysosome in Giardia lamblia.

    Abodeely, Marla; DuBois, Kelly N; Hehl, Adrian; Stefanic, Sasa; Sajid, Mohammed; DeSouza, Wanderley; Attias, Marcia; Engel, Juan C; Hsieh, Ivy; Fetter, Richard D; McKerrow, James H

    2009-11-01

    The dynamic evolution of organelle compartmentalization in eukaryotes and how strictly compartmentalization is maintained are matters of ongoing debate. While the endoplasmic reticulum (ER) is classically envisioned as the site of protein cotranslational translocation, it has recently been proposed to have pluripotent functions. Using transfected reporter constructs, organelle-specific markers, and functional enzyme assays, we now show that in an early-diverging protozoan, Giardia lamblia, endocytosis and subsequent degradation of exogenous proteins occur in the ER or in an adjacent and communicating compartment. The Giardia endomembrane system is simple compared to those of typical eukaryotes. It lacks peroxisomes, a classical Golgi apparatus, and canonical lysosomes. Giardia orthologues of mammalian lysosomal proteases function within an ER-like tubulovesicular compartment, which itself can dynamically communicate with clathrin-containing vacuoles at the periphery of the cell to receive endocytosed proteins. These primitive characteristics support Giardia's proposed early branching and could serve as a model to study the compartmentalization of endocytic and lysosomal functions into organelles distinct from the ER. This system also may have functional similarity to the retrograde transport of toxins and major histocompatibility complex class I function in the ER of mammals. PMID:19749174

  6. An ER-directed transcriptional response to unfolded protein stress in the absence of conserved sensor-transducer proteins in Giardia lamblia.

    Spycher, Cornelia; Herman, Emily K; Morf, Laura; Qi, Weihong; Rehrauer, Hubert; Aquino Fournier, Catharine; Dacks, Joel B; Hehl, Adrian B

    2013-05-01

    The protozoan Giardia lamblia has a minimized organelle repertoire, and most strikingly lacks a classical stacked Golgi apparatus. Nevertheless, Giardia trophozoites constitutively secrete variant surface proteins, and dramatically increase the volume of protein secretion during differentiation to cysts. Eukaryotic cells have evolved an elaborate system for quality control (QC) of protein folding and capacity in the endoplasmic reticulum (ER). Upon ER-overload, an unfolded protein response (UPR) is triggered on transcriptional/translational level aiming at alleviating ER stress. In Giardia, a minimized secretory machinery and absence of glycan-dependent QC suggests that a genetically conserved UPR (or functional equivalent) to cope with insults to the secretory system has been eliminated. We tested this hypothesis of UPR elimination by profiling the transcriptional response during induced ER-folding stress. We show that on the contrary, ER-folding stress triggers a stressor-specific, ER-directed response with upregulation of only ~ 30 genes, with different kinetics and scope compared with the UPR of other eukaryotes. Computational genomics revealed conserved cis-acting motifs in upstream regions of responder genes capable of stressor-specific gene regulation in transfected cells. Interestingly, the sensors/transducers of folding stress, well conserved in model eukaryotes, are absent in Giardia suggesting the presence of a novel version of this essential eukaryotic function. PMID:23617761

  7. Molecular Characterization of the Iranian Isolates of Giardia Lamblia: Application of the Glutamate Dehydrogenase Gene

    L Akhlaghi

    2008-07-01

    Full Text Available Background: This study was conducted to determine of molecular epidemiology of the Giardia lamblia by PCR-RFLP method in Tehran, capital of Iran. Methods: Thirty eight stool samples were randomly selected from 125 patients diagnosed with giardiasis using microscopy in Tehran. DNA extraction of some samples were performed by phenol/chloroform/isoamyl alcohol method and to raise the sensitivity of the PCR assay, the genomic DNA of the others were extracted using glass beads and the QIAamp Stool Mini Kit in order to effectively remove the PCR inhibitors. A single step PCR-RFLP assay, targeting the glutamate dehydrogenase (gdh locus, was used to differentiate within and between assemblages A and B that have been found in humans. Results: Of the 38 isolates, 33 samples (87% were found as G. lamblia (genotype AII, 3 (7.8% belonged to assemblage B, genotype BIII, the mixed of genotype AII and B were detected only in two samples (5.2%. Conclusions: PCR-RFLP is a sensitive and powerful analytical tool that allows effective genotype discrimination within and between assemblages at targeting gdh gene, and makes it possible to identify the presence of mixed genotypes. Our data suggest that there is an anthroponotic origin of the infection route, assemblage A group II, in Tehran so it seems that the main reservoir of Giardia infection is humans in the area studies.

  8. Effects of essential oils on the growth of Giardia lamblia trophozoites.

    Machado, Marisa; Sousa, Maria do Céu; Salgueiro, Lígia; Cavaleiro, Carlos

    2010-01-01

    Giardia lamblia is one of the most important worldwide causes of intestinal infections produced by protozoa. Current therapy for giardiasis is unsatisfactory due to high incidence of undesirable side effects and significant failure in clearing parasites from the gastrointestinal tract. In the search for new therapeutic agents, we report on the effect of several essential oils on G. lamblia growth. Among eighteen tested essential oils, those with phenolic compositions were the most active, particularly if containing high contents of carvacrol, such as Thymbra capitata and Origanum virens (IC50 values of 71 and 85 microg x mL(-1), respectively). The oils from Syzygium aromaticum and Thymus zygis subsp. sylvestris (IC50 values from 100 to 200 microg x mL(-1)), as well as, those from Mentha x piperita and Lippia graveolens (IC50 values over 200 microg x mL(-1)) were less active. Results support the concept that several essential oils or some of their constituents may be useful in the clinical management of Giardia infections. PMID:20184039

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

    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. Cloning, Expression and Characterization of Recombinant, NADH Oxidase from Giardia lamblia.

    Castillo-Villanueva, Adriana; Méndez, Sara Teresa; Torres-Arroyo, Angélica; Reyes-Vivas, Horacio; Oria-Hernández, Jesús

    2016-02-01

    The NADH oxidase family of enzymes catalyzes the oxidation of NADH by reducing molecular O2 to H2O2, H2O or both. In the protozoan parasite Giardia lamblia, the NADH oxidase enzyme (GlNOX) produces H2O as end product without production of H2O2. GlNOX has been implicated in the parasite metabolism, the intracellular redox regulation and the resistance to drugs currently used against giardiasis; therefore, it is an interesting protein from diverse perspectives. In this work, the GlNOX gene was amplified from genomic G. lamblia DNA and expressed in Escherichia coli as a His-Tagged protein; then, the enzyme was purified by immobilized metal affinity chromatography, characterized, and its properties compared with those of the endogenous enzyme previously isolated from trophozoites (Brown et al. in Eur J Biochem 241(1):155-161, 1996). In comparison with the trophozoite-extracted enzyme, which was scarce and unstable, the recombinant heterologous expression system and one-step purification method produce a stable protein preparation with high yield and purity. The recombinant enzyme mostly resembles the endogenous protein; where differences were found, these were attributable to methodological discrepancies or artifacts. This homogenous, pure and functional protein preparation can be used for detailed structural or functional studies of GlNOX, which will provide a deeper understanding of the biology and pathogeny of G. lamblia. PMID:26685698

  11. Giardia cyst wall protein 1 is a lectin that binds to curled fibrils of the GalNAc homopolymer.

    Aparajita Chatterjee

    Full Text Available The infectious and diagnostic stage of Giardia lamblia (also known as G. intestinalis or G. duodenalis is the cyst. The Giardia cyst wall contains fibrils of a unique beta-1,3-linked N-acetylgalactosamine (GalNAc homopolymer and at least three cyst wall proteins (CWPs composed of Leu-rich repeats (CWP(LRR and a C-terminal conserved Cys-rich region (CWP(CRR. Our goals were to dissect the structure of the cyst wall and determine how it is disrupted during excystation. The intact Giardia cyst wall is thin (approximately 400 nm, easily fractured by sonication, and impermeable to small molecules. Curled fibrils of the GalNAc homopolymer are restricted to a narrow plane and are coated with linear arrays of oval-shaped protein complex. In contrast, cyst walls of Giardia treated with hot alkali to deproteinate fibrils of the GalNAc homopolymer are thick (approximately 1.2 microm, resistant to sonication, and permeable. The deproteinated GalNAc homopolymer, which forms a loose lattice of curled fibrils, is bound by native CWP1 and CWP2, as well as by maltose-binding protein (MBP-fusions containing the full-length CWP1 or CWP1(LRR. In contrast, neither MBP alone nor MBP fused to CWP1(CRR bind to the GalNAc homopolymer. Recombinant CWP1 binds to the GalNAc homopolymer within secretory vesicles of Giardia encysting in vitro. Fibrils of the GalNAc homopolymer are exposed during excystation or by treatment of heat-killed cysts with chymotrypsin, while deproteinated fibrils of the GalNAc homopolymer are degraded by extracts of Giardia cysts but not trophozoites. These results show the Leu-rich repeat domain of CWP1 is a lectin that binds to curled fibrils of the GalNAc homopolymer. During excystation, host and Giardia proteases appear to degrade bound CWPs, exposing fibrils of the GalNAc homopolymer that are digested by a stage-specific glycohydrolase.

  12. A simple fibril and lectin model for cyst walls of Entamoeba and perhaps Giardia

    Samuelson, John; Robbins, Phillips

    2011-01-01

    Cyst walls of Entamoeba and Giardia protect them from environmental insults, stomach acids, and intestinal proteases. Each cyst wall contains a sugar homopolymer: chitin in Entamoeba and a unique N-acetylgalactosamine (GalNAc) homopolymer in Giardia. Entamoeba cyst wall proteins include Jacob lectins (carbohydrate-binding proteins) that cross-link chitin, chitinases that degrade chitin, and Jessie lectins that make walls impermeable. Giardia cyst wall proteins are also lectins that bind fibri...

  13. Nitroimidazole carboxamides as antiparasitic agents targeting Giardia lamblia, Entamoeba histolytica and Trichomonas vaginalis.

    Jarrad, A M; Debnath, A; Miyamoto, Y; Hansford, K A; Pelingon, R; Butler, M S; Bains, T; Karoli, T; Blaskovich, M A T; Eckmann, L; Cooper, M A

    2016-09-14

    Diarrhoeal diseases caused by the intestinal parasites Giardia lamblia and Entamoeba histolytica constitute a major global health burden. Nitroimidazoles are first-line drugs for the treatment of giardiasis and amebiasis, with metronidazole 1 being the most commonly used drug worldwide. However, treatment failures in giardiasis occur in up to 20% of cases and development of resistance to metronidazole is of concern. We have re-examined 'old' nitroimidazoles as a foundation for the systematic development of next-generation derivatives. Using this approach, derivatisation of the nitroimidazole carboxamide scaffold provided improved antiparasitic agents. Thirty-three novel nitroimidazole carboxamides were synthesised and evaluated for activity against G. lamblia and E. histolytica. Several of the new compounds exhibited potent activity against G. lamblia strains, including metronidazole-resistant strains of G. lamblia (EC50 = 0.1-2.5 μM cf. metronidazole EC50 = 6.1-18 μM). Other compounds showed improved activity against E. histolytica (EC50 = 1.7-5.1 μM cf. metronidazole EC50 = 5.0 μM), potent activity against Trichomonas vaginalis (EC50 = 0.6-1.4 μM cf. metronidazole EC50 = 0.8 μM) and moderate activity against the intestinal bacterial pathogen Clostridium difficile (0.5-2 μg/mL, cf. metronidazole = 0.5 μg/mL). The new compounds had low toxicity against mammalian kidney and liver cells (CC50 > 100 μM), and selected antiparasitic hits were assessed for human plasma protein binding and metabolic stability in liver microsomes to demonstrate their therapeutic potential. PMID:27236016

  14. Prevalence of Entamoeba histolytica, Giardia lamblia, and Cryptosporidium spp. in Libya: 2000–2015

    Ghenghesh, Khalifa Sifaw; Ghanghish, Khaled; BenDarif, Elloulu T.; Shembesh, Khaled; Franka, Ezzadin

    2016-01-01

    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 important for effective control of infection in at-risk populations. Methods The data were obtained by an English language literature search of Medline and PubMed for papers using the search terms ‘intestinal parasites and Libya, G. lamblia and Libya, E. histolytica and Libya and Cryptosporidium and Libya’ for the period 2000–2015. Results The data obtained for the period 2000–2015 showed prevalence rates of 0.8–36.6% (mean 19.9%) for E. histolytica/dispar, 1.2–18.2% (mean 4.6%) for G. lamblia and 0.9–13% (mean 3.4%) for Cryptosporidium spp. among individuals in Libya with gastroenteritis (GE). On the other hand, prevalence rates of 0.8–16.3% (mean 8.3%), 1.8–28.8% (mean 4.8%), and 1.0–2.5% (mean=2.4), respectively, were observed for individuals without GE. The mean prevalence rate of E. histolytica/dispar was significantly higher among individuals with GE compared with those without GE (phistolytica, G. lamblia, and Cryptosporidium spp. may play a minor role in GE in Libya. The observed high prevalence rates of E. histolytica/dispar reported from Libya could be due mainly to the non-pathogenic E. dispar and E. moshkovskii. However, more studies are needed in the future using E. histolytica-specific enzyme immunoassays and/or molecular methods to confirm this observation. PMID:27363524

  15. In Vitro Effect of Folic Acid and Cobalamin (Vitamin B12 on Adhesion and Growth of Giardia lamblia

    H Dalimi Asl

    2006-08-01

    Full Text Available Giardia lamblia is one of the most common intestinal protozoan parasites infecting human in the world. The goal of this study was searching for in-vitro effect of folic acid and cobalamin on adhesion and growth of G. lamblia as two important mechanisms in the pathogenesis in TYI-S-33 medium. G. lamblia trophozoites were obtained by in- vitro excystation procedure. Three groups of Giardia trophozoites were analyzed: control group, G.lamblia was cultured in TYI-S-33 without any vitamin, 2nd group with 0.1 µg/ml vitamin B12 or folic acid, and 3rd group with 0.5 µg/ml of vitamin B12 or folic acid. All culture media tubes incubated at 37 ºC. After 2 h of incubation, the adherence into borosilicate culture tubes, and after 24 h the growth of trophozoites were measured .The results showed that in vitamin B12 groups, the growth was increased significantly (P≤ 0.05 but the adherence decreased significantly (P≤ 0.05. Folic acid inhibited the growth rate significantly (P≤ 0.05, but it increased adherence in axenic culture significantly (P≤ 0.05. The results showed that vitamin B12 and folic acid altogether might reduce pathogenesis of G. lamblia by reducing adherence and growth, respectively.

  16. In-vitro susceptibility of Giardia lamblia to albendazole, mebendazole and other chemotherapeutic agents.

    Cedillo-Rivera, R; Muñoz, O

    1992-09-01

    The susceptibility of a strain of Giardia lamblia to benzimidazole carbamates, 5-nitroimidazoles, nitrofurans and other drugs was studied in vitro. Albendazole was the most active compound, with a 50% inhibitory concentration (IC50) of 0.01 mg/L and a minimal lethal concentration (MLC) of less than 0.04 mg/L; the IC50 of mebendazole was 0.06 mg/L and the MLC less than 0.5 mg/L. Among the 5-nitroimidazoles tested, ornidazole was the most effective (IC50 0.12 mg/L); tinidazole, metronidazole, secnidazole and hemezole were less active. Nifuroxazide, etofamide and nalidixic acid exhibited modest anti-giardial activity; quinfamide did not inhibit the growth of the parasite at a concentration of 200 mg/L. Albendazole and mebendazole are promising candidates for clinical use and should be further evaluated. PMID:1518040

  17. Caracterização genética de Giardia lamblia de origem humana e animal em Portugal

    Eduardo, José Machado da Costa

    2008-01-01

    Giardia lamblia é um organismo protozoário capaz de infectar o tracto intestinal de diversas espécies de animais onde se incluem os mamíferos. A heterogeneidade genética de G. lamblia está devidamente comprovada mas o seu potencial zoonótico continua ainda por esclarecer. Neste trabalho, analisaram-se 68 amostras de DNA obtidas a partir de fezes de origem humana e canina, com o objectivo de identificar os assemblages/genótipos que circulam no nosso país. Os resultados obtidos mostraram que...

  18. Metabolism of nitro drugs metronidazole and nitazoxanide in Giardia lamblia: characterization of a novel nitroreductase (GlNR2).

    Müller, Joachim; Schildknecht, Patricia; Müller, Norbert

    2013-01-01

    OBJECTIVES The protozoan parasite Giardia lamblia causes giardiasis, a persistent diarrhoea. Nitro drugs such as the nitroimidazole metronidazole and the nitrothiazolide nitazoxanide are used for the treatment of giardiasis. Nitroreductases may play a role in activating these drugs. G. lamblia contains two nitroreductases, GlNR1 and GlNR2. The aim of this work was to elucidate the role of GlNR2. METHODS Expression of GlNR2 was analysed by reverse transcription PCR. Recombinant GlN...

  19. Characteristics and risk factors for symptomatic Giardia lamblia infections in Germany

    Stark Klaus

    2010-01-01

    Full Text Available Abstract Background In developed countries, giardiasis is considered a travel related disease. However, routine surveillance data from Germany indicate that >50% of infections were acquired indigenously. We studied the epidemiological characteristics of symptomatic Giardia infections acquired in Germany and abroad, and verified the proportion of cases acquired in Germany in order to investigate risk factors for sporadic autochthonous Giardia infections. Methods We identified Giardia cases notified by 41 local health authorities between February 2007 and January 2008 and interviewed them on their clinical symptoms, underlying morbidities, travel abroad and potential risk factors for the disease. We conducted a case-control-study including laboratory-confirmed (microscopy or antigen-test autochthonous Giardia cases with clinical manifestations (diarrhoea, cramps, bloating and randomly selected controls from the local population registry matched by county of residence and age-group (0-5, 6-19, ≥20 years. Secondary cases, controls with diarrhoea and persons who had travelled outside Germany in the three weeks prior to disease onset (exposure period were excluded. We calculated adjusted odds ratios (aOR with 95% confidence intervals (CI using conditional logistic regression. Results Of 273 interviewed cases, 131 (48% had not travelled abroad during the defined exposure period. Of these 131, 85 (65% were male, 68 (54% were living in communities with >100,000 inhabitants and 107 (83% were aged 20 years or older. We included 120 cases and 240 controls in the case-control study. Cases were more likely to be male (aOR 2.5 CI 1.4-4.4, immunocompromised (aOR 15.3 CI 1.8-127 and daily consumers of green salad (aOR 2.9 CI 1.2-7.2. Contact with animals (pets/farm animals and exposure to surface water (swimming/water sports were not associated with symptomatic disease. Conclusions A substantial proportion of Giardia lamblia cases in Germany are indigenously

  20. Glucosylceramide synthesis inhibition affects cell cycle progression, membrane trafficking, and stage differentiation in Giardia lamblia.

    Stefanić, Sasa; Spycher, Cornelia; Morf, Laura; Fabriàs, Gemma; Casas, Josefina; Schraner, Elisabeth; Wild, Peter; Hehl, Adrian B; Sonda, Sabrina

    2010-09-01

    Synthesis of glucosylceramide via glucosylceramide synthase (GCS) is a crucial event in higher eukaryotes, both for the production of complex glycosphingolipids and for regulating cellular levels of ceramide, a potent antiproliferative second messenger. In this study, we explored the dependence of the early branching eukaryote Giardia lamblia on GCS activity. Biochemical analyses revealed that the parasite has a GCS located in endoplasmic reticulum (ER) membranes that is active in proliferating and encysting trophozoites. Pharmacological inhibition of GCS induced aberrant cell division, characterized by arrest of cytokinesis, incomplete cleavage furrow formation, and consequent block of replication. Importantly, we showed that increased ceramide levels were responsible for the cytokinesis arrest. In addition, GCS inhibition resulted in prominent ultrastructural abnormalities, including accumulation of cytosolic vesicles, enlarged lysosomes, and clathrin disorganization. Moreover, anterograde trafficking of the encystations-specific protein CWP1 was severely compromised and resulted in inhibition of stage differentiation. Our results reveal novel aspects of lipid metabolism in G. lamblia and specifically highlight the vital role of GCS in regulating cell cycle progression, membrane trafficking events, and stage differentiation in this parasite. In addition, we identified ceramide as a potent bioactive molecule, underscoring the universal conservation of ceramide signaling in eukaryotes. PMID:20335568

  1. First genotyping of Giardia lamblia from human and animal feces in Argentina, South America

    Marta C Minvielle

    2008-02-01

    Full Text Available The purpose of this study was to investigate the genotypes of Giardia lamblia from human and animal feces and their epidemiological and clinical characteristics in Argentina, South America. Seventy isolates, 60 from humans (adults and children, eight from dogs and two from cows were processed by polymerase chain reaction-restriction fragment length polymorphism. Data corresponding to demographic, socio-cultural and environmental variables and presence/absence of signs/symptoms were collected. The triosephosphate isomerase gene was amplified from 43 (71.66% of the 60 human fecal samples. Among these, 3/43 (6.98% were genotype AII and 40/43 (93.02% were genotype B. Assemblage AII was detected in three children who lived together in a shantytown and they were oligosymptomatic and none had diarrhea. This genotype was not found in animals. Genotype B showed a high prevalence in both adults and children. It was also found in polysymptomatic people, many of whom presented diarrhea. It was also found only in one dog. The present study represents the first contribution to the knowledge of G. lamblia genotypes in Argentina.

  2. Impacto de la dieta sobre la inducción de infección con quistes de Giardia lamblia en ratas Sprague-Dawley The effect of malnourishment on the development of giardiosis in Sprague-Dawley rats

    Martha Elvia Díaz-Cinco

    2002-07-01

    Full Text Available Objetivo. Evaluar el efecto de la desnutrición en la inducción de la giardiosis con diferentes concentraciones de quistes de Giardia lamblia utilizando como modelo animal ratas Sprague-Dawley. Material y métodos. Es un estudio experimental efectuado entre 1995 y 1999, en el Centro de Investigación en Alimentación y Desarrollo, de la ciudad de Hermosillo, estado de Sonora, México, y cuya muestra estuvo integrada por dos grupos de 6 a 8 unidades experimentales, las cuales recibieron dos tipos de dieta y cinco tratamientos con diferente concentración de inóculo de quistes de Giardia lamblia. Durante la fase experimental se monitoreó la excreción de quistes, ganancia de peso, consumo de alimento, análisis del contenido intestinal y daños macro y microscópicos en mucosa intestinal. El tratamiento estadístico de los datos consistió en análisis de varianza, y de residuales cuando fue necesario. Resultados. En los animales alimentados con una dieta que cubre sus requerimientos nutricionales (DN se observó que es posible provocar la infección con 60 quistes, mientras que en los animales desnutridos (dieta DLN la concentración que se requiere es de únicamente seis quistes para establecer daños a nivel de mucosa intestinal. Conclusiones. La ganancia de peso monitoreada durante los 10 días de ensayo no resultó ser un buen indicador de la infección por Giardia lamblia. El porcentaje de infección depende de la concentración de quistes inoculados y del estado de nutrición de los animales evaluados.Objective. To assess the effect of malnutrition on the development of giardiosis in Sprague-Dawley rats, using different inoculum sizes of Giardia lamblia cysts. Material and Methods. An experimental study was conducted between 1995 and 1999 at Centro de Investigación, Alimentación y Desarrollo (Center for Research, Food, and Development, in Hermosillo, Sonora, Mexico. The study population consisted of two groups of six to eight

  3. Modeling and analysis of propulsion in the multiflagellated micoorganism Giardia lamblia

    Lenaghan, Scott C.; Chen, Jun; Zhang, Mingjun

    2013-07-01

    The goal of this work was to analyze the propulsion of multiflagellated microorganisms, and to draw insight to the underlying physics and biology of the movement. Giardia lamblia was chosen as the model organism due to its unique ability to mechanically attach to various surfaces, its rapid movement, and its fine control over steering and navigation. In this work, a mechanics model was utilized to study the mechanics and propulsive contribution of the ventral and anterior flagella in Giardia. It was discovered that energy is supplied mainly at the proximal portion of these flagella, supporting the hypothesis that a decreasing adenosine triphosphate (ATP) gradient along the length of the flagella would not affect the motion observed. Similarly, the elasticity of the flagella allows the energy input at the proximal portion to be transferred to the distal portion, where the majority of thrust is generated. Specifically, we found that the ventral flagella are the driving force for planar propulsion and turning, while the anterior flagella are used for steering and control.

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

    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...

  5. Structural and evolutionary characteristics of pyruvate phosphate dikinase in Giardia lamblia and other amitochondriate protozoa

    Feng Xianmin; Yang Chunlin; Zheng Wenyu; Wen Jianfan

    2014-01-01

    Background Pyruvate phosphate dikinase (PPDK) reversibly catalyzes the interconversion of phosphoenolpyruvate (PEP) and pyruvic acid,leading to catabolism and adenosine triphosphate (ATP) synthesis or gluconeogenesis and ATP consumption.Molecular modeling of PPDKs from divergent organisms demonstrates that the orientation of the phosphorylatable histidine residue within the central domain of PPDK determines whether this enzyme promotes catabolism or gluconeogenesis.The goal of this study was to determine whether PDDK from Giardia underwent adaptive evolution in order to produce more energy under anaerobic conditions.Methods A total of 123 PPDK sequences from protozoans,proteobacteria,plants,and algae were selected,based upon sequence similarities to Giardia lamblia PPDK and Zea mays PPDK.Three-dimensional (3-D) models were generated for PPDKs from divergent organisms and were used to compare the orientation of the phosphorylatable histidine residue within the central domain of PPDKs.These PPDKs were compared using a maximum-likelihood tree.Results For PPDK from Giardia,as well as from other anaerobic protozoans,the central domain tilted toward the N-terminal nucleotide-binding domain,indicating that this enzyme catalyzed ATP synthesis.Furthermore,the orientation of this central domain was determined by interactions between the N-and C-terminal domains.Phylogenetic analysis of the N-and C-terminal sequences of PPDKs from different species suggested that PPDK has likely undergone adaptive evolution in response to differences in environmental and metabolic conditions.Conclusion These results suggested that PPDK in anaerobic organisms is functionally adapted to generate energy more efficiently in an anaerobic environment.

  6. First genotyping of Giardia lamblia from human and animal feces in Argentina, South America

    Minvielle, Marta Cecilia; Molina, Nora Beatriz; Polverino, Daniela; Basualdo, Juan A.

    2008-01-01

    The purpose of this study was to investigate the genotypes of Giardia lamblia from human and animal feces and their epidemiological and clinical characteristics in Argentina, South America. Seventy isolates, 60 from humans (adults and children), eight from dogs and two from cows were processed by polymerase chain reaction-restriction fragment length polymorphism. Data corresponding to demographic, socio-cultural and environmental variables and presence/absence of signs/symptoms were collected...

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

    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.

  8. Membrane trafficking and organelle biogenesis in Giardia lamblia: use it or lose it.

    Faso, Carmen; Hehl, Adrian B

    2011-04-01

    The secretory transport capacity of Giardia trophozoites is perfectly adapted to the changing environment in the small intestine of the host and is able to deploy essential protective surface coats as well as molecules which act on epithelia. These lumen-dwelling parasites take up nutrients by bulk endocytosis through peripheral vesicles or by receptor-mediated transport. The environmentally-resistant cyst form is quiescent but poised for activation following stomach passage. Its versatility and fidelity notwithstanding, the giardial trafficking systems appear to be the product of a general secondary reduction process geared towards minimization of all components and machineries identified to date. Since membrane transport is directly linked to organelle biogenesis and maintenance, less complexity also means loss of organelle structures and functions. A case in point is the Golgi apparatus which is missing as a steady-state organelle system. Only a few basic Golgi functions have been experimentally demonstrated in trophozoites undergoing encystation. Similarly, mitochondrial remnants have reached a terminally minimized state and appear to be functionally restricted to essential iron-sulfur protein maturation processes. Giardia's minimized organization combined with its genetic tractability provides unique opportunities to study basic principles of secretory transport in an uncluttered cellular environment. Not surprisingly, Giardia is gaining increasing attention as a model for the investigation of gene regulation, organelle biogenesis, and export of simple but highly protective cell wall biopolymers, a hallmark of all perorally transmitted protozoan and metazoan parasites. PMID:21296082

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

    Nguah Samuel

    2011-08-01

    Full Text Available Abstract Background 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. Method 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. Results 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 Enterobius vermicularis, Taenia spp and Trichuris trichiura were not seen in any of the stool samples. Conclusion Giardia lamblia is the most prevalent intestinal parasite in examined stool samples of children within the

  10. DETECTION AND IDENTIFICATION OF 'GIARDIA' CYSTS USING IMMUNOFLUORESCENCE AND PHASE CONTRAST MICROSCOPY

    Detection and identification of Giardia cysts in water samples has been improved by the development of an immunofluorescent method that specifically stains Giardia cysts bright green and allows their easy detection against a black background. The report discusses aspects of the m...

  11. A detailed look at the cytoskeletal architecture of the Giardia lamblia ventral disc.

    Brown, Joanna R; Schwartz, Cindi L; Heumann, John M; Dawson, Scott C; Hoenger, Andreas

    2016-04-01

    Giardia lamblia is a protistan parasite that infects and colonizes the small intestine of mammals. It is widespread and particularly endemic in the developing world. Here we present a detailed structural study by 3-D negative staining and cryo-electron tomography of a unique Giardia organelle, the ventral disc. The disc is composed of a regular array of microtubules and associated sheets, called microribbons that form a large spiral, held together by a myriad of mostly unknown associated proteins. In a previous study we analyzed by cryo-electron tomography the central microtubule portion (here called disc body) of the ventral disc and found a large portion of microtubule associated inner (MIPs) and outer proteins (MAPs) that render these microtubules hyper-stable. With this follow-up study we expanded our 3-D analysis to different parts of the disc such as the ventral and dorsal areas of the overlap zone, as well as the outer disc margin. There are intrinsic location-specific characteristics in the composition of microtubule-associated proteins between these regions, as well as large differences between the overall architecture of microtubules and microribbons. The lateral packing of microtubule-microribbon complexes varies substantially, and closer packing often comes with contracted lateral tethers that seem to hold the disc together. It appears that the marginal microtubule-microribbon complexes function as outer, laterally contractible lids that may help the cell to clamp onto the intestinal microvilli. Furthermore, we analyzed length, quantity, curvature and distribution between different zones of the disc, which we found to differ from previous publications. PMID:26821343

  12. Use of immunofluorescence and phase-contrast microscopy for detection and identification of Giardia cysts in water samples.

    Sauch, J F

    1985-01-01

    A method was developed in which indirect immunofluorescence and phase-contrast microscopy are used for rapid detection and identification of Giardia cysts in raw and finished water supplies. When anti-Giardia cyst antiserum and fluorescein conjugate were applied to known Giardia cysts on membrane filters, the cysts fluoresced bright green when they were illuminated by UV light. This procedure permitted individual cysts to be quickly located even in samples heavily contaminated with other micr...

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

    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.

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

    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.

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

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

    2015-01-01

    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. PMID:26447336

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

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

    2015-01-01

    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...... assessed by seeding ColorSeed (10 replicates) into the filter unit followed by air backwash to a glass slide and counting of (oo-)cysts by epifluorescent microscopy. High recovery rates (meanSD) were found: 849%48 for Giardia cysts and 70%+/- 65 for Cryptosporidium oocysts. DNA of seeded wild type (oo...

  17. USE OF IMMUNOFLUORESCENCE AND PHASE-CONTRAST MICROSCOPY FOR DETECTION AND IDENTIFICATION OF 'GIARDIA' CYSTS IN WATER SAMPLES

    A method was developed in which indirect immunofluorescence and phase-contrast microscopy are used for rapid detection and identification of Giardia cysts in raw and finished water supplies. When anti-Giardia cyst antiserum and fluorescein conjugate were applied to known Giardia ...

  18. Identification of the Major Cysteine Protease of Giardia and Its Role in Encystation*S⃞

    DuBois, Kelly N.; Abodeely, Marla; Sakanari, Judy; Craik, Charles S.; Lee, Malinda; McKerrow, James H.; Sajid, Mohammed

    2008-01-01

    Giardia lamblia is a protozoan parasite and the earliest branching clade of eukaryota. The Giardia life cycle alternates between an asexually replicating vegetative form and an infectious cyst form. Encystation and excystation are crucial processes for the survival and transmission of Giardia. Cysteine proteases in Giardia have been implicated in proteolytic processing events that enable the continuance of the life cycle throughout encystation and excystation. Using qu...

  19. Crystal structure of a macrophage migration inhibitory factor from Giardia lamblia

    Buchko, Garry W.; Abendroth, Jan; Robinson, Howard; Zhang, Yanfeng; Hewitt, Stephen N.; Edwards, Tom E.; Van Voorhis, Wesley C.; Myler, Peter J.

    2013-06-15

    Macrophage migration inhibitory factor (MIF) is a eukaryotic cytokine that affects a broad spectrum of immune responses and its activation/inactivation is associated with numerous diseases. During protozoan infections MIF is not only expressed by the host, but, has also been observed to be expressed by some parasites and released into the host. To better understand the biological role of parasitic MIF proteins, the crystal structure of the MIF protein from Giardia lamblia (Gl-MIF), the etiological agent responsible for giardiasis, has been determined at 2.30 Å resolution. The 114-residue protein adopts an α/β fold consisting of a four-stranded β-sheet with two anti-parallel α-helices packed against a face of the β-sheet. An additional short β-strand aligns anti-parallel to β4 of the β-sheet in the adjacent protein unit to help stabilize a trimer, the biologically relevant unit observed in all solved MIF crystal structures to date, and form a discontinuous β-barrel. The structure of Gl-MIF is compared to the MIF structures from humans (Hs-MIF) and three Plasmodium species (falciparum, berghei, and yoelii). The structure of all five MIF proteins are generally similar with the exception of a channel that runs through the center of each trimer complex. Relative to Hs-MIF, there are differences in solvent accessibility and electrostatic potential distribution in the channel of Gl-MIF and the Plasmodium-MIFs due primarily to two “gate-keeper” residues in the parasitic MIFs. For the Plasmodium MIFs the gate-keeper residues are at positions 44 (Y==>R) and 100 (V==>D) and for Gl-MIF it is at position 100 (V==>R). If these gate-keeper residues have a biological function and contribute to the progression of parasitemia they may also form the basis for structure-based drug design targeting parasitic MIF proteins.

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

    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. PMID:27515076

  1. Clathrin-dependent pathways and the cytoskeleton network are involved in ceramide endocytosis by a parasitic protozoan, Giardia lamblia.

    Hernandez, Yunuen; Castillo, Cynthia; Roychowdhury, Sukla; Hehl, Adrian; Aley, Stephen B; Das, Siddhartha

    2007-01-01

    Although identified as an early-diverged protozoan, Giardia lamblia shares many similarities with higher eukaryotic cells, including an internal membrane system and cytoskeleton, as well as secretory pathways. However, unlike many other eukaryotes, Giardia does not synthesize lipids de novo, but rather depends on exogenous sources for both energy production and organelle or membrane biogenesis. It is not known how lipid molecules are taken up by this parasite and if endocytic pathways are involved in this process. In this investigation, we tested the hypothesis that highly regulated and selective lipid transport machinery is present in Giardia and necessary for the efficient internalization and intracellular targeting of ceramide molecules, the major sphingolipid precursor. Using metabolic and pathway inhibitors, we demonstrate that ceramide is internalized through endocytic pathways and is primarily targeted into perinuclear/endoplasmic reticulum membranes. Further investigations suggested that Giardia uses both clathrin-dependent pathways and the actin cytoskeleton for ceramide uptake, as well as microtubule filaments for intracellular localization and targeting. We speculate that this parasitic protozoan has evolved cytoskeletal and clathrin-dependent endocytic mechanisms for importing ceramide molecules from the cell exterior for the synthesis of membranes and vesicles during growth and differentiation. PMID:17087963

  2. Prevalence and Risk Factors of Giardia lamblia and Blastocystis hominis Infections in Children Under Ten Years Old, Hamadan, Iran

    Sedighi

    2015-05-01

    Full Text Available Background Nowadays, parasitic infections are a major health problem throughout the world, particularly in the developing countries. Objectives Considering the high susceptibility of children against parasitic infections, the current study aimed to determine the prevalence and associated risk factors of intestinal parasitic infections among children less than 10 years old in urban and rural areas of Hamadan district. Patients and Methods The current study was conducted on 395 children (214 males and 181 females, referred to urban and rural health centers in Hamadan district in 2013. Stool samples were examined by formalin-ether concentration technique, and trichrome and modified Ziehl-Neelsen staining methods. The results were analyzed by chi-square test. Results Of the 395 studied children, 112 (28.4% were infected with intestinal parasites. Blastocystis hominis was the most frequently detected parasite with the prevalence of 18.5%, followed by Giardia lamblia (10.9%, Entamoeba coli (2.8%, Dientamoeba fragilis (0.8%, Iodamoeba buetschlii (0.8%, Chilomastix mesnili (0.5%, Cryptosporidium spp. (0.5%, Endolimax nana (0.3% and Entamoeba hartmanni (0.3%. No cases of infection with helminth parasites were found. Conclusions The results of the study showed a high prevalence of Giardia lamblia and Blastocystis hominis in rural areas compared to urban regions. Therefore it is necessary to promote the public health awareness in the rural population, in order to reduce the frequency of parasitic infections.

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

    Williams Christopher W

    2011-11-01

    Full Text Available Abstract Background 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. Results 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. Conclusions 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

  4. FILTRATION OF 'GIARDIA' CYSTS AND OTHER SUBSTANCES. VOLUME 1. DIATOMACEOUS EARTH FILTRATION

    The effectiveness of diatomaceous earth filtration of drinking water was studied under various operating conditions for removal of Giardia cysts, total coliform bacteria, standard plate count bacteria, turbidity, and particles. Seven grades of diatomaceous earth were used. Temper...

  5. EVALUATION OF CRYPTOSPORIDIUM OOCYSTS AND GIARDIA CYSTS IN A WATERSHED RESERVOIR

    This investigation evaluated the occurrence of Cryptosporidium oocysts and Giardia cysts at 17 sampling locations in Lake Texoma reservoir using method 1623 with standard Envirocheck™ capsule filters. The watershed serves rural agricultural communities active in cattle ranching, ...

  6. Giardia Cysts and Cryptosporidium Oocysts in Membrane-Filtered Municipal Wastewater Used for Irrigation▿

    Lonigro, A.; Pollice, A; Spinelli, R; Berrilli, F.; Di Cave, D.; D'Orazi, C.; Cavallo, P; Brandonisio, O.

    2006-01-01

    A wastewater tertiary treatment system based on membrane ultrafiltration and fed with secondary-treated municipal wastewater was evaluated for its Giardia cyst and Cryptosporidium oocyst removal efficiency. Giardia duodenalis (assemblages A and B) and Cryptosporidium parvum were identified in feed water but were found in filtered water only during occasional failure of the filtration system.

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

    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

  8. Detection of viable Giardia cysts by amplification of heat shock-induced mRNA.

    Abbaszadegan, M; Huber, M. S.; Gerba, C P; Pepper, I L

    1997-01-01

    Primers obtained from gene sequences coding for heat shock proteins (HSP) were used to specifically detect enteric protozoans of the genus Giardia. The HSP primers amplified Giardia DNA or the corresponding RNA sequences obtained from lysed cysts and gave a 163-bp product. Since the presence of the product did not indicate whether the cysts were viable, these amplifications are a presence/absence test only. In contrast, amplification of heat shock-induced mRNA utilizing the same HSP primers w...

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

    Müller, Joachim; Rout, Samuel; Leitsch, David; Vaithilingam, Jathana; Hehl, Adrian; Müller, Norbert

    2015-08-01

    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. PMID:27099829

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

    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. Existence of Cryptosporidium spp. oocysts and Giardia spp. cysts in well water in Nineveh governorate

    R. G. Mohammad

    2011-01-01

    The study included examination of 110 water samples from well distributed in Mosul city and few towns and villages around it from May 2009 to March 2010 for detection of Cryptosporidium spp oocysts and Giardia spp cysts in well water. The results revealed that the prevalence of Cryptosporidium oocysts was 16.36% while the prevalence of Giardia cysts was 12.72%. The percentages of prevalence with Cryptosporidium and Giardia were in high rate in Bartilla and some villages around it 20% for Cryp...

  12. Dual acylation accounts for the localization of {alpha}19-giardin in the ventral flagellum pair of Giardia lamblia.

    Saric, Mirela; Vahrmann, Anke; Niebur, Daniela; Kluempers, Verena; Hehl, Adrian B; Scholze, Henning

    2009-10-01

    A Giardia-specific protein family denominated as alpha-giardins, represents the major protein component, besides tubulin, of the cytoskeleton of the human pathogenic parasite Giardia lamblia. One of its members, alpha19-giardin, carries an N-terminal sequence extension of MGCXXS, which in many proteins serves as a target for dual lipid conjugation: myristoylation at the glycine residue after removal of the methionine and palmitoylation at the cysteine residue. As the first experimental evidence of a lipid modification, we found alpha19-giardin to be associated with the membrane fraction of disrupted trophozoites. After heterologous coexpression of alpha19-giardin with giardial N-myristoyltransferase (NMT) in Escherichia coli, we found the protein in a myristoylated form. Additionally, after heterologous expression together with the palmitoyl transferase Pfa3 in Saccharomyces cerevisiae, alpha19-giardin associates with the membrane of the main vacuole. Immunocytochemical colocalization studies on wild-type Giardia trophozoites with tubulin provide evidence that alpha19-giardin exclusively localizes to the ventral pair of the giardial flagella. A mutant in which the putatively myristoylated N-terminal glycine residue was replaced by alanine lost this specific localization. Our findings suggest that the dual lipidation of alpha19-giardin is responsible for its specific flagellar localization. PMID:19684283

  13. Aquatic biomonitoring of Giardia cysts and Cryptosporidium oocysts in peninsular Malaysia.

    Lee, Soo Ching; Ngui, Romano; Tan, Tiong Kai; Roslan, Muhammad Aidil; Ithoi, Init; Lim, Yvonne A L

    2014-01-01

    An aquatic biomonitoring of Giardia cysts and Cryptosporidium oocysts in river water corresponding to five villages situated in three states in peninsular Malaysia was determined. There were 51.3% (20/39) and 23.1% (9/39) samples positive for Giardia and Cryptosporidium (oo)cysts, respectively. Overall mean concentration between villages for Giardia cysts ranged from 0.10 to 25.80 cysts/l whilst Cryptosporidium oocysts ranged from 0.10 to 0.90 oocysts/l. Detailed results of the river samples from five villages indicated that Kuala Pangsun 100% (9/9), Kemensah 77.8% (7/9), Pos Piah 33.3% (3/9) and Paya Lebar 33.3% (1/3) were contaminated with Giardia cysts whilst Cryptosporidium (oo)cysts were only detected in Kemensah (100 %; 9/9) and Kuala Pangsun (66.6%; 6/9). However, the water samples from Bentong were all negative for these waterborne parasites. Samples were collected from lower point, midpoint and upper point. Midpoint refers to the section of the river where the studied communities are highly populated. Meanwhile, the position of the lower point is at least 2 km southward of the midpoint and upper point is at least 2 km northward of the midpoint. The highest mean concentration for (oo)cysts was found at the lower points [3.15 ± 6.09 (oo)cysts/l], followed by midpoints [0.66 ± 1.10 (oo)cysts/l] and upper points [0.66 ± 0.92 (oo)cysts/l]. The mean concentration of Giardia cysts was highest at Kuala Pangsun (i.e. 5.97 ± 7.0 cysts/l), followed by Kemensah (0.83 ± 0.81 cysts/l), Pos Piah (0.20 ± 0.35 cysts/l) and Paya Lebar (0.10 ± 0.19 cysts/l). On the other hand, the mean concentration of Cryptosporidium oocysts was higher at Kemensah (0.31 ± 0.19 cysts/l) compared to Kuala Pangsun (0.03 ± 0.03cysts/l). All the physical and chemical parameters did not show significant correlation with both protozoa. In future, viability status and molecular characterisation of Giardia and Cryptosporidium should be applied to identify

  14. Characteristics and risk factors for symptomatic Giardia lamblia infections in Germany

    Stark Klaus; an der Heiden Matthias; Espelage Werner; Alpers Katharina

    2010-01-01

    Abstract Background In developed countries, giardiasis is considered a travel related disease. However, routine surveillance data from Germany indicate that >50% of infections were acquired indigenously. We studied the epidemiological characteristics of symptomatic Giardia infections acquired in Germany and abroad, and verified the proportion of cases acquired in Germany in order to investigate risk factors for sporadic autochthonous Giardia infections. Methods We identified Giardia cases not...

  15. Static Clathrin Assemblies at the Peripheral Vacuole-Plasma Membrane Interface of the Parasitic Protozoan Giardia lamblia.

    Zumthor, Jon Paulin; Cernikova, Lenka; Rout, Samuel; Kaech, Andres; Faso, Carmen; Hehl, Adrian B

    2016-07-01

    Giardia lamblia is a parasitic protozoan that infects a wide range of vertebrate hosts including humans. Trophozoites are non-invasive but associate tightly with the enterocyte surface of the small intestine. This narrow ecological specialization entailed extensive morphological and functional adaptations during host-parasite co-evolution, including a distinctly polarized array of endocytic organelles termed peripheral vacuoles (PVs), which are confined to the dorsal cortical region exposed to the gut lumen and are in close proximity to the plasma membrane (PM). Here, we investigated the molecular consequences of these adaptations on the Giardia endocytic machinery and membrane coat complexes. Despite the absence of canonical clathrin coated vesicles in electron microscopy, Giardia possesses conserved PV-associated clathrin heavy chain (GlCHC), dynamin-related protein (GlDRP), and assembly polypeptide complex 2 (AP2) subunits, suggesting a novel function for GlCHC and its adaptors. We found that, in contrast to GFP-tagged AP2 subunits and DRP, CHC::GFP reporters have no detectable turnover in living cells, indicating fundamental differences in recruitment to the membrane and disassembly compared to previously characterized clathrin coats. Histochemical localization in electron tomography showed that these long-lived GlCHC assemblies localized at distinctive approximations between the plasma and PV membrane. A detailed protein interactome of GlCHC revealed all of the conserved factors in addition to novel or highly diverged proteins, including a putative clathrin light chain and lipid-binding proteins. Taken together, our data provide strong evidence for giardial CHC as a component of highly stable assemblies at PV-PM junctions that likely have a central role in organizing continuities between the PM and PV membranes for controlled sampling of the fluid environment. This suggests a novel function for CHC in Giardia and the extent of molecular remodeling of

  16. Static Clathrin Assemblies at the Peripheral Vacuole—Plasma Membrane Interface of the Parasitic Protozoan Giardia lamblia

    Zumthor, Jon Paulin; Cernikova, Lenka; Rout, Samuel; Kaech, Andres; Faso, Carmen; Hehl, Adrian B.

    2016-01-01

    Giardia lamblia is a parasitic protozoan that infects a wide range of vertebrate hosts including humans. Trophozoites are non-invasive but associate tightly with the enterocyte surface of the small intestine. This narrow ecological specialization entailed extensive morphological and functional adaptations during host-parasite co-evolution, including a distinctly polarized array of endocytic organelles termed peripheral vacuoles (PVs), which are confined to the dorsal cortical region exposed to the gut lumen and are in close proximity to the plasma membrane (PM). Here, we investigated the molecular consequences of these adaptations on the Giardia endocytic machinery and membrane coat complexes. Despite the absence of canonical clathrin coated vesicles in electron microscopy, Giardia possesses conserved PV-associated clathrin heavy chain (GlCHC), dynamin-related protein (GlDRP), and assembly polypeptide complex 2 (AP2) subunits, suggesting a novel function for GlCHC and its adaptors. We found that, in contrast to GFP-tagged AP2 subunits and DRP, CHC::GFP reporters have no detectable turnover in living cells, indicating fundamental differences in recruitment to the membrane and disassembly compared to previously characterized clathrin coats. Histochemical localization in electron tomography showed that these long-lived GlCHC assemblies localized at distinctive approximations between the plasma and PV membrane. A detailed protein interactome of GlCHC revealed all of the conserved factors in addition to novel or highly diverged proteins, including a putative clathrin light chain and lipid-binding proteins. Taken together, our data provide strong evidence for giardial CHC as a component of highly stable assemblies at PV-PM junctions that likely have a central role in organizing continuities between the PM and PV membranes for controlled sampling of the fluid environment. This suggests a novel function for CHC in Giardia and the extent of molecular remodeling of

  17. Static Clathrin Assemblies at the Peripheral Vacuole-Plasma Membrane Interface of the Parasitic Protozoan Giardia lamblia.

    Jon Paulin Zumthor

    2016-07-01

    Full Text Available Giardia lamblia is a parasitic protozoan that infects a wide range of vertebrate hosts including humans. Trophozoites are non-invasive but associate tightly with the enterocyte surface of the small intestine. This narrow ecological specialization entailed extensive morphological and functional adaptations during host-parasite co-evolution, including a distinctly polarized array of endocytic organelles termed peripheral vacuoles (PVs, which are confined to the dorsal cortical region exposed to the gut lumen and are in close proximity to the plasma membrane (PM. Here, we investigated the molecular consequences of these adaptations on the Giardia endocytic machinery and membrane coat complexes. Despite the absence of canonical clathrin coated vesicles in electron microscopy, Giardia possesses conserved PV-associated clathrin heavy chain (GlCHC, dynamin-related protein (GlDRP, and assembly polypeptide complex 2 (AP2 subunits, suggesting a novel function for GlCHC and its adaptors. We found that, in contrast to GFP-tagged AP2 subunits and DRP, CHC::GFP reporters have no detectable turnover in living cells, indicating fundamental differences in recruitment to the membrane and disassembly compared to previously characterized clathrin coats. Histochemical localization in electron tomography showed that these long-lived GlCHC assemblies localized at distinctive approximations between the plasma and PV membrane. A detailed protein interactome of GlCHC revealed all of the conserved factors in addition to novel or highly diverged proteins, including a putative clathrin light chain and lipid-binding proteins. Taken together, our data provide strong evidence for giardial CHC as a component of highly stable assemblies at PV-PM junctions that likely have a central role in organizing continuities between the PM and PV membranes for controlled sampling of the fluid environment. This suggests a novel function for CHC in Giardia and the extent of molecular

  18. ISOLATION AND DETECTION OF GIARDIA CYSTS FROM WATER USING DIRECT IMMUNOFLUORESCENCE.

    Sorenson, Stephen K.; Riggs, John L.; Dileanis, Peter D.; Suk, Thomas J.

    1986-01-01

    A water-sampling apparatus used for the isolation and detection of Giardia cysts in water has been designed and tested. The sampling apparatus uses one of a variety of pumps or waterline pressure to move water through a filter. Two of the optional pumps are lightweight enough to make the apparatus portable and thus suitable for sampling in remote areas. This technique of sample processing produces good cyst recovery in much less time than is required with previously established methods. Giardia cysts are identified using direct immunofluorescence.

  19. Hydrologic and vegetative removal of Cryptosporidium parvum, Giardia lamblia, and Toxoplasma gondii Surrogate microspheres in coastal wetlands.

    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; Miller, Woutrina A

    2013-03-01

    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

  20. Expression, purification, crystallization and preliminary X-ray diffraction analysis of α-11 giardin from Giardia lamblia

    Pathuri, Puja; Nguyen, Emily Tam [Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697 (United States); Luecke, Hartmut, E-mail: hudel@uci.edu [Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697 (United States); Department of Physiology and Biophysics, University of California, Irvine, CA 92697 (United States); Department of Information and Computer Sciences, University of California, Irvine, CA 92697 (United States)

    2006-11-01

    α-11 giardin from the intestinal protozoan parasite, G. lamblia has been cloned, expressed, purified and crystallized under two different conditions and in two different space groups. Crystals from the first condition diffracted to 1.1 Å and belong to a primitive orthorhombic space group and crystals obtained in the second condition diffracted to 2.93 Å and belong to a primitive monoclinic space group. α-11 Giardin, a protein from the annexin superfamily, is a 35.0 kDa protein from the intestinal protozoan parasite Giardia lamblia which triggers a form of diarrhea called giardiasis. Here, the cloning, expression, purification and the crystallization of α-11 giardin under two different conditions and in two different space groups is reported. Crystals from the first condition diffracted to 1.1 Å and belong to a primitive orthorhombic space group, while crystals from the second condition, which included calcium in the crystallization solution, diffracted to 2.93 Å and belong to a primitive monoclinic space group. Determination of the detailed atomic structure of α-11 giardin will provide a better insight into its biological function and might establish whether this class of proteins is a potential drug target against giardiasis.

  1. Identification and evolutionary implication of four novel box H/ACA snoRNAs from Giardia lamblia

    LUO Jun; ZHOU Hui; CHEN Chongjian; LI Yan; CHEN Yueqin; QU Lianghu

    2006-01-01

    From a specialized cDNA library, four novel box H/ACA snoRNAs, named GLsR22,GLsR23, GLsR24 and GLsR25, were identified from the primitive eukaryote, Giardia lamblia. Bioinformatics analyses indicated that all of them can be potentially folded into double hairpins, the typical secondary structures of box H/ACA snoRNAs. GLsR24 and GLsR25 are predicted to guide the site-specific pseudouridylation at U1753 and U2396 on 23S rRNA,respectively, while GLsR22 and GLsR23 belong to the family of "orphan" snoRNAs. All of the four novel snoRNAs are encoded by single copy genes and located in small intergenic regions. Interestingly,compared with the counterparts previously reported in Archaea and other unicellular protozoan, the box H/ACA snoRNAs identified from G. lamblia have unique structural features, implying that snoRNAs evolved from prokaryotes to eukaryotes in different ways.

  2. Expression, purification, crystallization and preliminary X-ray diffraction analysis of α-11 giardin from Giardia lamblia

    α-11 giardin from the intestinal protozoan parasite, G. lamblia has been cloned, expressed, purified and crystallized under two different conditions and in two different space groups. Crystals from the first condition diffracted to 1.1 Å and belong to a primitive orthorhombic space group and crystals obtained in the second condition diffracted to 2.93 Å and belong to a primitive monoclinic space group. α-11 Giardin, a protein from the annexin superfamily, is a 35.0 kDa protein from the intestinal protozoan parasite Giardia lamblia which triggers a form of diarrhea called giardiasis. Here, the cloning, expression, purification and the crystallization of α-11 giardin under two different conditions and in two different space groups is reported. Crystals from the first condition diffracted to 1.1 Å and belong to a primitive orthorhombic space group, while crystals from the second condition, which included calcium in the crystallization solution, diffracted to 2.93 Å and belong to a primitive monoclinic space group. Determination of the detailed atomic structure of α-11 giardin will provide a better insight into its biological function and might establish whether this class of proteins is a potential drug target against giardiasis

  3. Characterization of Giardia lamblia genotypes in dogs from Tucson, Arizona using SSU-rRNA and β-giardin sequences.

    Johansen, K M; Castro, N S; Lancaster, K E; Madrid, E; Havas, A; Simms, J; Sterling, C R

    2014-01-01

    The objective of this study was to determine if human genotypes of Giardia lamblia could be found in canine companion animals from urban and peri-urban environments in Tucson, Arizona. Canine fecal samples collected from the Humane Society of Southern Arizona between July 2006 and April 2009 were screened for G. lamblia infection using immunofluorescent microscopy and confirmed by polymerase chain reaction (PCR). Of the 672 samples screened, 196 were found positive by IFA and 185 of those positive were successfully amplified through PCR. Sequencing analysis showed samples were primarily of the C or D genotypes (n =154), or showing a mix of the C and D genotypes (n =10). One sample showed a mixed infection of a human genotype (A) and a dog-specific genotype (C). These data are consistent with previous studies showing dog specific genotypes to be dominant in environments where dog-to-dog transmission is likely to occur, and provides further evidence that multiple genes should be targeted for more accurate genotype characterization. PMID:24233408

  4. 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

    Escolástico Aguiar González

    2002-06-01

    habitats. These protozoan investigation and detection have acquired importance in the last years due to their dispersion forms, which show resistance to the habitual treatments of potabilization and purification, and their classification as emerging pathogens which are the causative agents of important hydrical transmission outbreaks.In our work, Giardia lamblia cyst and Cryptosporidium spp. oocyst presence in Santa Cruz de Tenerife treated wastewater which is transported to the South of the island to be reutilised in agriculture. Furthermore, transport, storage and advanced treatment effects against cyst and oocyst concentration throughout the system and relation existence with other bacteriological and physical-chemical parameters, are also investigated.The obtained results demonstrate variable behaviours in cyst and oocyst concentration against applied treatments, and the depurative effect of the long-distance transport which seems to have in treated wastewater.There was not found any relation between cyst and oocyst concentration in treated wastewater and the traditional indicators of faecal contamination.

  5. Cryptosporidium oocysts and giardia cysts on salad products irrigated with contaminated water.

    Amorós, Inmaculada; Alonso, José L; Cuesta, Gonzalo

    2010-06-01

    A field study in Valencia, Spain, was done to determine the occurrence of Giardia and Cryptosporidium on salad products that are frequently eaten raw, such as lettuces and Chinese cabbage, and in irrigation waters. Four water samples were taken weekly 1 month before harvesting the vegetables. All water samples were analyzed using techniques included in the U.S. Environmental Protection Agency Method 1623. Standard methods for detecting protozoan parasites on salad vegetables are not available. Published techniques for the isolation of parasites from vegetables generally have low and variable recovery efficiencies. In this study, vegetables were analyzed using a recently reported method for detection of Cryptosporidium oocysts and Giardia cysts on salad products. The waters tested were positive for both Cryptosporidium and Giardia. Of 19 salad products studied, we observed Cryptosporidium in 12 samples and Giardia in 10 samples. Recoveries of the Texas Red-stained Cryptosporidium and Giardia, which were used as internal controls, were 24.5% +/- 3.5% for Cryptosporidium and 16.7% +/- 8.1% for Giardia (n = 8). This study provides data on the occurrence of Cryptosporidium and Giardia in salad products in Spain. The method was useful in the detection of Cryptosporidium oocysts and Giardia cysts on the vegetables tested, and it provides a useful analytical tool for occurrence monitoring. PMID:20537274

  6. Oral Immunization of BALB/c Mice with Giardia duodenalis Recombinant Cyst Wall Protein Inhibits Shedding of Cysts

    Larocque, R; Nakagaki, K.; Lee, P.; Abdul-Wahid, A.; Faubert, G M

    2003-01-01

    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 immunogen...

  7. Occurrence of Cryptosporidium Oocysts and Giardia Cysts in Sewage in Norway†

    Robertson, L. J.; Hermansen, L.; Gjerde, B. K.

    2006-01-01

    Samples of sewage influent from 40 sewage treatment works (STW) throughout Norway were examined for Cryptosporidium oocysts and Giardia duodenalis cysts. Both parasites were detected frequently (80% of STW were Cryptosporidium positive; 93% of STW were Giardia positive) and at maximum concentrations of >20,000 parasites/liter. The data suggest giardiasis is more widespread, and/or occurs with greater infection intensity, than cryptosporidiosis in Norway. STW serving higher person equivalents ...

  8. Molecular Characterization of Giardia lamblia: First Report of Assemblage B in Human Isolates from Rio de Janeiro (Brazil)

    Faria, Clarissa Perez; Zanini, Graziela Maria; Dias, Gisele Silva; da Silva, Sidnei; Sousa, Maria do Céu

    2016-01-01

    Background Despite the high prevalence of giardiasis, the genetic characterization of Giardia lamblia has been poorly documented in Brazil and molecular epidemiology research has only been conducted in the last few years. The aim of this study was to determine the prevalence of different G. lamblia assemblages and detect mixed infections among patients with giardiasis. Methods and Principal Findings The cross-section survey was conducted among patients attending the FIOCRUZ in Rio de Janeiro. In order to discriminate the genetic assemblages/sub-assemblages, G. lamblia isolates were characterized by PCR-RFLP and qPCR using four loci genes (bg, gdh, tpi and orfC4). Of the 65 positive samples, 41 (63.1%) were successfully amplified by nested-PCR of bg and gdh genes. Among them, 16 were typed as sub-assemblage AII, 7 as BIII, 4 as BIV and 8 as a mixture of BIII and BIV. After the analysis by qPCR assay, a total of 55 (84.6%) samples were amplified using at least one locus: bg gene was amplified in 38 (58.5%) samples, gdh in 41 (63.1%), tpi in 39 (60%), and orfC4 in 39 (60%). Multilocus genotyping results showed that 29 (52.7%) samples belonged to Assemblage A and 26 (47.3%) samples belonged to Assemblage B. In 2011 and 2012, 20 (74.1%) samples belonged to Assemblage A and 7 (25.9%) belonged to Assemblage B. In subsequent years (2013–2015) there was a predominance of Assemblage B, 19 (67.9%) versus 9 (32.1%) Assemblage A. Conclusions This is the first time that Assemblage B of G. lamblia was reported in human clinical samples from Rio de Janeiro (Brazil) and is the first report about genetic characterization using four genes. The qPCR assemblage-specific showed no mixed infections by Assemblages A and B. A switch in genetic profile over the years was observed, firstly predominance of Assemblage A and lastly of Assemblage B. PMID:27517469

  9. Effects of Dietary Zinc Manipulation on Growth Performance, Zinc Status and Immune Response during Giardia lamblia Infection: A Study in CD-1 Mice

    Humberto Astiazarán-García

    2013-09-01

    Full Text Available Associations between Giardia lamblia infection and low serum concentrations of zinc have been reported in young children. Interestingly, relatively few studies have examined the effects of different dietary zinc levels on the parasite-infected host. The aims of this study were to compare the growth performance and zinc status in response to varying levels of dietary zinc and to measure the antibody-mediated response of mice during G. lamblia infection. Male CD-1 mice were fed using 1 of 4 experimental diets: adequate-zinc (ZnA, low-zinc (ZnL, high-zinc (ZnH and supplemented-zinc (ZnS diet containing 30, 10, 223 and 1383 mg Zn/kg respectively. After a 10 days feeding period, mice were inoculated orally with 5 × 106 G. lamblia trophozoites and were maintained on the assigned diet during the course of infection (30 days. Giardia-free mice fed ZnL diets were able to attain normal growth and antibody-mediated response. Giardia-infected mice fed ZnL and ZnA diets presented a significant growth retardation compared to non-infected controls. Zinc supplementation avoided this weight loss during G. lamblia infection and up-regulated the host’s humoral immune response by improving the production of specific antibodies. Clinical outcomes of zinc supplementation during giardiasis included significant weight gain, higher anti-G. lamblia IgG antibodies and improved serum zinc levels despite the ongoing infection. A maximum growth rate and antibody-mediated response were attained in mice fed ZnH diet. No further increases in body weight, zinc status and humoral immune capacity were noted by feeding higher zinc levels (ZnS than the ZnH diet. These findings probably reflect biological effect of zinc that could be of public health importance in endemic areas of infection.

  10. Evaluation of nine immunoassay kits (enzyme immunoassay and direct fluorescence) for detection of Giardia lamblia and Cryptosporidium parvum in human fecal specimens.

    Garcia, L S; Shimizu, R Y

    1997-01-01

    It is well known that Giardia lamblia and Cryptosporidium parvum can cause severe symptoms in humans, particularly those who are immunologically compromised. Immunoassay procedures offer both increased sensitivity and specificity compared to conventional staining methods. These reagents are also helpful when screening large numbers of patients, particularly in an outbreak situation or when screening patients with minimal symptoms. The data obtained by using 9 diagnostic kits were compared: di...

  11. 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

    Abreu Acosta, N.; Macrina Martín Delgado; Antonio Ortega Rivas; Antonio del Castillo Remiro; Escolástico Aguiar González; Basilio Valladares Hernández

    2002-01-01

    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 habitats. These protozoan investigation and detection have acquired importance in the last years due to their dispersion forms, which show resistance to the habitual treatments of potabilization and purif...

  12. Existence of Cryptosporidium spp. oocysts and Giardia spp. cysts in well water in Nineveh governorate

    R. G. Mohammad

    2011-01-01

    Full Text Available The study included examination of 110 water samples from well distributed in Mosul city and few towns and villages around it from May 2009 to March 2010 for detection of Cryptosporidium spp oocysts and Giardia spp cysts in well water. The results revealed that the prevalence of Cryptosporidium oocysts was 16.36% while the prevalence of Giardia cysts was 12.72%. The percentages of prevalence with Cryptosporidium and Giardia were in high rate in Bartilla and some villages around it 20% for Cryptosporidium and 17.14% for Giardia, the low rates were in Mosul city 10% for both protozoa. The highest prevalence rate of Cryptosporidium was in March 38.46% and the lowest was in November and July 0%. The highest prevalence rate of Giardia was in October 23.53% and the lowest rate in July 0%. This first study shows the presence of Cryptosporidium oocysts and Giardia cysts in well water (Ground water in Nineveh governorate.

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

    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

  14. Oxidative stress-induced cell cycle blockage and a protease-independent programmed cell death in  microaerophilic Giardia lamblia

    Esha Ghosh

    2009-03-01

    Full Text Available Esha Ghosh1, Arjun Ghosh1, Amar Nath Ghosh2, Tomoyoshi Nozaki3, Sandipan Ganguly11Division of Parasitology; 2Division of Electron Microscopy, National Institute of Cholera and Enteric Diseases, Beliaghata, Kolkata, West Bengal, India; 3Division of Parasitology, National Institute of Infectious Diseases, Tokyo, JapanAbstract: Giardia lamblia is a microaerophilic human gastrointestinal parasite and considered as an early-diverged eukaryote. In vitro oxidative stress generation plays a significant role in cell cycle progression and cell death of this parasite. In the present study hydrogen peroxide, metronidazole, and a modified growth medium without cysteine and ascorbic acid have been chosen as oxidative stress-inducing agents. Cell cycle progression has been found to be regulated by different types of oxidative stresses. Apoptosis is not an established pathway in Giardia, which is devoid of ideal mitochondria, but in the present investigation, apoptosis-like programmed cell death has been found by the experiments like AnnexinV-FITC assay, DNA fragmentation pattern, etc. On the contrary, Caspase-9 assay, which confirms the caspase-mediated apoptotic pathway, has been found to be negative in all the stress conditions. Protease inhibitor assay confirmed that, even in absence of any proteases, programmed cell death does occur in this primitive eukaryote. All these results signify a novel pathway of programmed suicidal death in Giardia lamblia under oxidative stress. This is the first demonstration of protease-independent programmed cell death regulation in Giardia exclusive for its own specialties.Keywords: Giardia lamblia, oxidative stress, reactive oxygen species, programmed cell death, apoptosis, early branching eukaryotes

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

    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. PMID:26657313

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

    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 micro-o

  17. MATRIX ASSISTED LASER DESORPTION/IONIZATION TIME OF FLIGHT MASS SPECTROMETRY BASED ANALYSIS OF GIARDIA LAMBLIA

    Giardia is the protozoan parasite that is the etiologic agent of giardiasis. This illness is the most common parasitic disease, estimated to infect 2.5 million people in the United States and up to 280 million people worldwide each year [8,19]. Symptoms of giardiasis range from ...

  18. A Ten-year Survey of Giardia Cysts in Drinking Water Supplies of Seoul, the Republic of Korea

    Lee, Mok-Young; Cho, Eun-Joo; Lee, Jin-Hyo; Han, Sun-Hee; Park, Yong-Sang

    2011-01-01

    To understand the distribution of Giardia cysts in drinking water supplies in Seoul, Korea, we collected water samples quarterly at 6 intakes in the Han River, its largest stream and 6 conventional water treatment plants (WTPs) serving drinking water, from 2000 to 2009. Giardia cysts in each of 10 L water were confirmed in 35.0% of intake water samples and the arithmetic mean was 1.65 cysts/10 L (range 0-35 cysts/10 L). The lowest cyst density was observed at Paldang and Kangbuk intakes, and ...

  19. Freqüência de Giardia lamblia em cães atendidos em clínicas veterinárias de Porto Alegre, RS, Brasil Frequency of Giardia lamblia in dogs attended by veterinary clinics in Porto Alegre city, RS, Brazil

    Adriane Bartmann; Flávio Antônio Pacheco de Araújo

    2004-01-01

    A pesquisa de cistos de Giardia lamblia em fezes de cães oriundos de clínicas veterinárias de Porto Alegre, RS, Brasil, foi realizada pelo método de FAUST et al. (1939). Das 526 amostras analisadas, 38% (198) foram positivas para cistos de G. lamblia, sendo 22% (116) constituídos por animais menores de 11 meses de idade e 16% (82) constituídos por animais com 12 meses ou mais de idade. Houve diferença significativa (p

  20. Giardia y giardiasis Giardia and giardiasis

    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

  1. Phenotypic and genotypic variation in Giardia lamblia isolates during chronic infection.

    Butcher, P D; Cevallos, A M; Carnaby, S; Alstead, E M; Swarbrick, E T; Farthing, M J

    1994-01-01

    Two Giardia isolates were axenised in vitro after recovery by duodenal aspiration from a man with hypo-gamma globulinaemia and chronic giardiasis, before and after three unsuccessful courses of metronidazole. In vitro drug sensitivity assays showed that the pretreatment isolate was sensitive to metronidazole with minimum inhibitory concentration (MIC) and dose that inhibited growth by 50% (ED50) values of 0.1 and 0.03 mumol/l, respectively. The post-treatment isolate was 20-fold more resistan...

  2. 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.

    Chatterjee, Aparajita; Bandini, Giulia; Motari, Edwin; Samuelson, John

    2015-11-01

    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

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

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

    2011-01-01

    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....... Results: The results showed that exposure of Cryptosporidium oocysts and Giardia cysts to ultrasound could reduce their survival rate even if the exposure time was limited to a few seconds. When sonication time was extended, changes in parasite characteristics became clearly visible. Several other factors...

  4. Prevalence of and associated risk factors for shedding Cryptosporidium parvum oocysts and Giardia cysts within feral pig populations in California.

    Atwill, E. R.; Sweitzer, R A; M. G. Pereira; Gardner, I A; Van Vuren, D; Boyce, W. M.

    1997-01-01

    Populations of feral pigs (Sus scrofa) may serve as an environmental reservoir of Cryptosporidium parvum oocysts and Giardia sp. cysts for source water. We conducted a cross-sectional study to determine the prevalence of and associated demographic and environmental risk factors for the shedding of C. parvum oocysts and Giardia sp. cysts. Feral pigs were either live-trapped or dispatched from 10 populations located along the coastal mountains of western California, and fecal samples were obtai...

  5. Impacto de la dieta sobre la inducción de infección con quistes de Giardia lamblia en ratas Sprague-Dawley

    Díaz-Cinco Martha Elvia

    2002-01-01

    Full Text Available Objetivo. Evaluar el efecto de la desnutrición en la inducción de la giardiosis con diferentes concentraciones de quistes de Giardia lamblia utilizando como modelo animal ratas Sprague-Dawley. Material y métodos. Es un estudio experimental efectuado entre 1995 y 1999, en el Centro de Investigación en Alimentación y Desarrollo, de la ciudad de Hermosillo, estado de Sonora, México, y cuya muestra estuvo integrada por dos grupos de 6 a 8 unidades experimentales, las cuales recibieron dos tipos de dieta y cinco tratamientos con diferente concentración de inóculo de quistes de Giardia lamblia. Durante la fase experimental se monitoreó la excreción de quistes, ganancia de peso, consumo de alimento, análisis del contenido intestinal y daños macro y microscópicos en mucosa intestinal. El tratamiento estadístico de los datos consistió en análisis de varianza, y de residuales cuando fue necesario. Resultados. En los animales alimentados con una dieta que cubre sus requerimientos nutricionales (DN se observó que es posible provocar la infección con 60 quistes, mientras que en los animales desnutridos (dieta DLN la concentración que se requiere es de únicamente seis quistes para establecer daños a nivel de mucosa intestinal. Conclusiones. La ganancia de peso monitoreada durante los 10 días de ensayo no resultó ser un buen indicador de la infección por Giardia lamblia. El porcentaje de infección depende de la concentración de quistes inoculados y del estado de nutrición de los animales evaluados.

  6. 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

    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

  7. The anti-giardial effectiveness of fungal and commercial chitosan against Giardia intestinalis cysts in vitro.

    Yarahmadi, Mohammad; Fakhar, Mahdi; Ebrahimzadeh, Mohammad Ali; Chabra, Aroona; Rahimi-Esboei, Bahman

    2016-03-01

    Chitosan with poly-N-acetylglucosamine sequences is a deacetylated derivative of chitin that can be found in the exoskeletons of crabs, shrimp and lobsters, the cuticles of insects and the cell walls of fungi. The aim of the present study was to compare the effects of fungal chitosan (FC) prepared from the cell walls of Penicillium viridicatum and Penicillium aurantiogriseum with commercially available chitosan (CC) against Giardia intestinalis cysts in vitro. The giardia cysts were isolated using a sucrose method. Four concentrations (50, 100, 200 and 400 μg/ml) of each type of prepared chitosan were applied for 10, 30, 60 and 180 min. The viability of the cysts was checked via 0.1 % eosin staining. Our results indicate that P. viridicatum (with a 47.5 % DD) and P. aurantiogriseum (with a 47.3 % DD) at different concentrations after 180 min precipitated, respectively, 56, 69, 81 and 100 %, and 63, 75, 86 and 100 % mortality rates. CC (with a 54 % DD) showed 79, 84, 93 and 100 % mortality rates. In conclusion, both FC and CC at 400 μg/ml concentrations after 180 min of exposure showed the most potent effect against G. intestinalis cysts. Accordingly, chitosan could be suggested as a new natural nanoform agent for future research in the safe and effective treatment of Giardia infections. PMID:27065602

  8. Impacto de la dieta sobre la inducción de infección con quistes de Giardia lamblia en ratas Sprague-Dawley

    Díaz-Cinco Martha Elvia; Ballesteros-Vázquez Martha Nydia; Pérez-Morales Rosalba; Mata-Haro Verónica

    2002-01-01

    Objetivo. Evaluar el efecto de la desnutrición en la inducción de la giardiosis con diferentes concentraciones de quistes de Giardia lamblia utilizando como modelo animal ratas Sprague-Dawley. Material y métodos. Es un estudio experimental efectuado entre 1995 y 1999, en el Centro de Investigación en Alimentación y Desarrollo, de la ciudad de Hermosillo, estado de Sonora, México, y cuya muestra estuvo integrada por dos grupos de 6 a 8 unidades experimentales, las cuales recibieron dos tipos d...

  9. The single epsin homolog in Giardia lamblia localizes to the ventral disk of trophozoites and is not associated with clathrin membrane coats.

    Ebneter, Jacqueline A; Hehl, Adrian B

    2014-10-01

    Epsins serve as recruitment platforms for clathrin membrane coat protein components and induce membrane curvature via their N-terminal homology (ENTH) domain. Unexpectedly, the single ENTH domain protein, a putative epsinR homolog (Glepsin), in the diverged protozoan parasite Giardia lamblia, localizes exclusively to the specialized attachment organelle, the ventral disk (VD). Glepsin binds both to phosphatidylinositol (3,4,5)-trisphosphate phospholipids and the VD cytoskeleton, but lacks canonical domains for interaction with clathrin coat components. This suggests reassignment of giardial epsin function from membrane trafficking to a structural role in linking the plasma membrane to the highly specialized VD during evolution of this genus. PMID:25286382

  10. Predominance of Giardia lamblia assemblage A among iron deficiency anaemic pre-school Egyptian children.

    Hussein, Eman M; Zaki, Wafaa M; Ahmed, Shahira A; Almatary, Amal M; Nemr, Nader I; Hussein, Abdalla M

    2016-04-01

    Intestinal parasites and nutritional deficiency can coexist and influence each other. This study aimed to clarify the association between Giardia genotypes and presence of iron deficiency anaemia (IDA) among pre-school Egyptian children. Two groups (IDA and non-anaemic) of giardiasis children (44/group) were selected according to their recovery response after treatment of giardiasis. Each group included 24 and 20 gastrointestinal symptomatic and asymptomatic, respectively. Giardia human genotypes were performed by intergenic spacer (IGS) gene based polymerase chain reaction (PCR) with high-resolution melting curve (HRM). PCR/HRM proved that Tms of assemblage A and B ranged from 79.31 ± 0.29 to 84.77 ± 0.31. In IDA patients, assemblages A and B were found among 40/44 (90.9 %) and 4/44 (9.1 %), respectively, while in non-anaemic patients, assemblages A and B were found in 10/44 (22.7 %) and 32/44 (72.7 %), respectively, beside two (4.6 %) cases had mixed infection. The difference was statistically significant. No significant relation was found between symptomatic or asymptomatic assemblages and IDA as assemblage A was found in 21/24 (87.5 %) and 19/20 (95 %) of symptomatic and asymptomatic, respectively, while 3/24 (12.5 %) and 1/20 (5 %) of assemblage B were symptomatic was asymptomatic, respectively. A significant relation was found between assemblage A subtypes distribution among IDA patients as AI and AII were detected on 23 (52.3 %) and 16 (36.4 %) of patients, respectively, while one case (2.3 %) had mixed infection. In conclusion, assemblage A is predominant among IDA giardiasis children suggesting its role in enhancing the occurrence of IDA while B has a protective role. PMID:26758448

  11. Structural and functional perturbation of Giardia lamblia triosephosphate isomerase by modification of a non-catalytic, non-conserved region.

    Gloria Hernández-Alcántara

    Full Text Available BACKGROUND: We have previously proposed triosephosphate isomerase of Giardia lamblia (GlTIM as a target for rational drug design against giardiasis, one of the most common parasitic infections in humans. Since the enzyme exists in the parasite and the host, selective inhibition is a major challenge because essential regions that could be considered molecular targets are highly conserved. Previous biochemical evidence showed that chemical modification of the non-conserved non-catalytic cysteine 222 (C222 inactivates specifically GlTIM. The inactivation correlates with the physicochemical properties of the modifying agent: addition of a non-polar, small chemical group at C222 reduces the enzyme activity by one half, whereas negatively charged, large chemical groups cause full inactivation. RESULTS: In this work we used mutagenesis to extend our understanding of the functional and structural effects triggered by modification of C222. To this end, six GlTIM C222 mutants with side chains having diverse physicochemical characteristics were characterized. We found that the polarity, charge and volume of the side chain in the mutant amino acid differentially alter the activity, the affinity, the stability and the structure of the enzyme. The data show that mutagenesis of C222 mimics the effects of chemical modification. The crystallographic structure of C222D GlTIM shows the disruptive effects of introducing a negative charge at position 222: the mutation perturbs loop 7, a region of the enzyme whose interactions with the catalytic loop 6 are essential for TIM stability, ligand binding and catalysis. The amino acid sequence of TIM in phylogenetic diverse groups indicates that C222 and its surrounding residues are poorly conserved, supporting the proposal that this region is a good target for specific drug design. CONCLUSIONS: The results demonstrate that it is possible to inhibit species-specifically a ubiquitous, structurally highly conserved enzyme by

  12. Rational Design Synthesis and Evaluation of First Generation Inhibitors of the Giardia Lamblia Fructose-1 6-biphosphate Aldolase

    Z Li; Z Liu; D Cho; J Zou; M Gong; R Breece; A Galkin; L Li; H Zhao; et al.

    2011-12-31

    Inhibitors of the Giardia lamblia fructose 1,6-bisphosphate aldolase (GlFBPA), which transforms fructose 1,6-bisphosphate (FBP) to dihydroxyacetone phosphate and glyceraldehyde 3-phosphate, were designed based on 3-hydroxy-2-pyridone and 1,2-dihydroxypyridine scaffolds that position two negatively charged tetrahedral groups for interaction with substrate phosphate binding residues, a hydrogen bond donor to the catalytic Asp83, and a Zn{sup 2+} binding group. The inhibition activities for the GlFBPA catalyzed reaction of FBP of the prepared alkyl phosphonate/phosphate substituted 3-hydroxy-2-pyridinones and a dihydroxypyridine were determined. The 3-hydroxy-2-pyridone inhibitor 8 was found to bind to GlFBPA with an affinity (K{sub i} = 14 {micro}M) that is comparable to that of FBP (K{sub m} = 2 {micro}M) or its inert analog TBP (K{sub i} = 1 {micro}M). The X-ray structure of the GlFBPA-inhibitor 8 complex (2.3 {angstrom}) shows that 8 binds to the active site in the manner predicted by in silico docking with the exception of coordination with Zn{sup 2+}. The observed distances and orientation of the pyridone ring O=C-C-OH relative to Zn{sup 2+} are not consistent with a strong interaction. To determine if Zn{sup 2+} coordination occurs in the GlFBPA-inhibitor 8 complex in solution, EXAFS spectra were measured. A four coordinate geometry comprised of the three enzyme histidine ligands and an oxygen atom from the pyridone ring O=C-C-OH was indicated. Analysis of the Zn{sup 2+} coordination geometries in recently reported structures of class II FBPAs suggests that strong Zn{sup 2+} coordination is reserved for the enediolate-like transition state, accounting for minimal contribution of Zn{sup 2+} coordination to binding of 8 to GlFBPA.

  13. A comparative study of different methods used in the detection of Giardia lamblia on fecal specimens of children

    Muhammad Farooq Baig

    2012-01-01

    Full Text Available Objective: The purpose of this study was to compare results obtained using a single fecal specimen for ova and parasite (O and P examination, direct immunofluorescent assay (DFA, and two conventional staining methods. Design: Fecal specimens of 150 children were collected and examined by each method. The O and P and the DFA were used as the reference methods. Setting: The study was performed at the laboratory in the Basic Medical Science Institute JPMC Karachi. Materials and Methods: The fecal specimens were collected from children with a suspected Giardia lamblia infection. Agreement and disagreement between the methods was determined based on (1 the presence of giardiasis in our population and (2 the sensitivity and specificity of each method. Results: There was 45 (30% positive and 105 (70% negative cases found with DFA, 41 (27.4% positive and 109 (72.6% negative cases detected by iodine method, and 34 (22.6% positive and 116 (77.4% negative cases found with saline method. The sensitivity and specificity of DFA in comparison to iodine were 92.2 and 92.7%, respectively. The sensitivity and specificity of DFA in comparison to saline method were 91.2 and 87.9%, respectively. The sensitivities of iodine method and saline method in comparison to DFA were 82.2 and 68.8%, respectively. There is marked difference in sensitivity of DFA compared to conventional methods. Conclusion: The study supported the findings of other investigators who concluded that DFA method has the greatest sensitivity. The immunologic methods were more efficient and quicker than the conventional O and P method.

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

    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 at...... predetermined time intervals to loosen all parasites and other particles from the filter and break up clusters. The concentrated parasite suspension was backwashed and counted after immuno-fluorescence staining. Results and discussion: Without sonication the recovery rates of both Cryptosporidium and Giardia...

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

    Maria Antonella Di Benedetto; Florinda Di Piazza; Carmelo Massimo Maida; Nino Romano

    2010-01-01

    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 livest...

  16. Giardia Cysts in Wastewater Treatment Plants in Italy

    Cacciò, Simone M; De Giacomo, Marzia; Aulicino, Francesca A.; Pozio, Edoardo

    2003-01-01

    Reductions in annual rainfall in some regions and increased human consumption have caused a shortage of water resources at the global level. The recycling of treated wastewaters has been suggested for certain domestic, industrial, and agricultural activities. The importance of microbiological and parasitological criteria for recycled water has been repeatedly emphasized. Among water-borne pathogens, protozoa of the genera Giardia and Cryptosporidium are known to be highly resistant to water t...

  17. Static tank depuration and chronic short-term experimental contamination of Eastern oysters (Crassostrea virginica) with Giardia duodenalis cysts.

    Willis, Jessica E; McClure, J T; McClure, Carol; Spears, Jonathan; Davidson, Jeff; Greenwood, Spencer J

    2015-01-01

    Cysts of the protozoan parasite Giardia have been detected in many bivalve shellfish species worldwide. The detection of zoonotic Giardia duodenalis assemblages A and B is of public health concern, yet there is limited data available demonstrating the bioaccumulation and elimination of Giardia cysts in bivalve shellfish. This study quantified G. duodenalis cysts that were filtered and retained by oysters (Crassostrea virginica) over a one week chronic exposure period, or 24 hour exposure followed by a 6 day depuration period, using static tank systems containing 10 L of 29 ppt water inoculated with 1000 or 10,000 cysts. Under chronic exposure, each oyster retained a mean of 13.4 and 87.4 cysts during the first 24h of exposure at low and high doses, respectively, and the cysts bioaccumulated at a rate of 1.2 and 6.8 cysts/oyster/day, respectively, for the remaining duration of the trials. In acute exposure trials, oysters retained 13.8 cysts or 78.9 cysts at low and high doses, respectively, during the initial 24 hour exposure and naturally depurated cysts at a rate of -0.92 cysts/oyster/day and -2.2 cysts/oyster/day, respectively, after transfer. Although most G. duodenalis cysts were eliminated within the first 24h via pseudofeces and feces, detection of some cysts in the fecal material on day 7 of acute exposure trials was indicative of cysts which passed through the digestive tract and released in feces. Only 48-53% of the initial tank inocula were recovered and may indicate that some cysts were selectively filtered by oysters but degraded through digestion. PMID:25305439

  18. Cryptosporidium and Giardia in Humans, Domestic Animals, and Village Water Sources in Rural India.

    Daniels, ME; Shrivastava, A.; Smith, WA; P. Sahu; Odagiri, M; Misra, PR; Panigrahi, P; Suar, M; Clasen, T; Jenkins, MW

    2015-01-01

    Cryptosporidium parvum and Giardia lamblia are zoonotic enteric protozoa of significant health concern where sanitation, hygiene, and water supplies are inadequate. We examined 85 stool samples from diarrhea patients, 111 pooled fecal samples by species across seven domestic animal types, and water from tube wells (N = 207) and ponds (N = 94) across 60 villages in coastal Odisha, India, for Cryptosporidium oocysts and Giardia cysts to measure occurrence, concentration/shedding, and environmen...

  19. A microRNA derived from an apparent canonical biogenesis pathway regulates variant surface protein gene expression in Giardia lamblia

    Saraiya, Ashesh A.; Li, Wei; Wang, Ching C.

    2011-01-01

    Giardia is a deeply branching unicellular eukaryote. Here, the authors provide evidence for a microRNA, miR4, that regulates the expression of variant surface proteins (VSPs). Biogenesis of this miRNA requires Giardia dicer and the miRNA to be associated with the Giardia Argonaute protein. These results suggest a very ancient origin of miRNA regulatory systems.

  20. THE EFFICIENCY OF YARN WOUND FILTERS IN GIARDIA CYSTS REMOVAL USING THE IMPROVED SUCROSE GRADIENT

    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

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

    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.

  2. The progress on detection methods of Giardia lamblia%蓝氏贾第鞭毛虫检测方法的研究进展

    朱海波; 李国清

    2010-01-01

    Giardia lamblia is an important waterborne zoonotic parasitic protozoan. It can cause diarrhea in humans and animals. Traditional detection methods are mainly stool examinations. With the application of immunological and molecular biology techniques, its immunological and molecular detection methods have made considerable developments in recent years. This article reviewed the progress in this field.%蓝氏贾第鞭毛虫是一种重要的水源性人兽共患的寄生原虫,可致人和动物的腹泻.传统的检测方法主要为粪便检查,随着免疫学与分子生物学技术的应用,其免疫学检测和分子生物学检测近年来有了较大的发展.该文就上述研究进展进行综述.

  3. Influence of Refrigeration and Formalin on the Floatability of Giardia duodenalis Cysts

    Maria da Luz Ribeiro Moitinho

    1999-07-01

    Full Text Available Giardia duodenalis cysts obtained from fresh fecal samples, fecal samples kept under refrigeration and fecal samples treated with formalin were studied as to their floatability on sucrose solutions with the following specific gravities: 1,040 kg/m3; 1,050 kg/m3; 1,060 kg/m3; 1,070 kg/m3; 1,080 kg/m3; 1,090 kg/m3; 1,100 kgm3; 1,150 kg/m3; 1,200 kg/m3; and 1,250 kg/m3, contained within counting-chambers 0.17 mm high. Cysts that floated on and those settled down as sediments were counted, and had their percentages estimated. Sucrose solutions of 1,200 kg/m3 specific gravity (the average specific gravity of diluting liquids employed in floatation techniques caused to float 77.7%, 78.4% and 6.6% of the G. duodenalis cysts obtained, respectively, from fresh fecal samples, fecal samples kept under refrigeration, and fecal samples treated with formalin. Cysts obtained both from fresh fecal samples and fecal samples kept under refrigeration presented similar results concerning floatability. It was observed, however, that the treatment of feces with formalin diminished the cysts floatability under the various specific gravities studied. This results should influence, the recommendations for transport and storage of fecal samples used for parasitological coproscopy.

  4. Validation of housekeeping genes as an internal control for gene expression studies in Giardia lamblia using quantitative real-time PCR.

    Marcial-Quino, Jaime; Fierro, Francisco; De la Mora-De la Mora, Ignacio; Enríquez-Flores, Sergio; Gómez-Manzo, Saúl; Vanoye-Carlo, America; Garcia-Torres, Itzhel; Sierra-Palacios, Edgar; Reyes-Vivas, Horacio

    2016-04-25

    The analysis of transcript levels of specific genes is important for understanding transcriptional regulation and for the characterization of gene function. Real-time quantitative reverse transcriptase PCR (RT-qPCR) has become a powerful tool to quantify gene expression. The objective of this study was to identify reliable housekeeping genes in Giardia lamblia. Twelve genes were selected for this purpose, and their expression was analyzed in the wild type WB strain and in two strains with resistance to nitazoxanide (NTZ) and metronidazole (MTZ), respectively. RefFinder software analysis showed that the expression of the genes is different in the three strains. The integrated data from the four analyses showed that the NADH oxidase (NADH) and aldolase (ALD) genes were the most steadily expressed genes, whereas the glyceraldehyde-3-phosphate dehydrogenase gene was the most unstable. Additionally, the relative expression of seven genes were quantified in the NTZ- and MTZ-resistant strains by RT-qPCR, using the aldolase gene as the internal control, and the results showed a consistent differential pattern of expression in both strains. The housekeeping genes found in this work will facilitate the analysis of mRNA expression levels of other genes of interest in G. lamblia. PMID:26778241

  5. Prevalence and spatial distribution of Entamoeba histolytica/dispar and Giardia lamblia among schoolchildren in Agboville area (Cote d'Ivoire.

    Mamadou Ouattara

    Full Text Available BACKGROUND: New efforts are being made to improve understanding of the epidemiology of the helminths and intensifying the control efforts against these parasites. In contrast, relatively few studies are being carried out in this direction for the intestinal protozoa. To contribute to a better comprehension of the epidemiology of the intestinal protozoa, prevalence, and spatial distribution of Entamoeba histolytica/dispar and Giardia lamblia, and their association with drinking water supplies, were determined in the Agboville department in southeast Côte d'Ivoire. METHODS/FINDINGS: Stool samples were taken from more than 1,300 schoolchildren in the third year of primary education (CE1 from 30 primary schools and preserved in SAF (sodium acetate-acetic acid-formalin. The samples were analyzed by formalin-ether concentration. Then, a survey questionnaire addressed to schoolchildren and school directors was used to collect data on water supplies. Prevalence of E. histolytica/dispar and G. lamblia were, respectively, 18.8% and 13.9%. No particular focus zone was observed in the spatial distribution of the two species. Significant negative association was observed between use of tap water and high prevalence of E. histolytica/dispar infection (OR = 0.83, p = 0.01. High prevalence of G. lamblia infection was positively associated with use of ponds as the source of drinking water (OR = 1.28, p = 0.009. CONCLUSION: These two species of pathogenic protozoa are present with substantial prevalence in this area of Côte d'Ivoire. Although their spatial distribution is not focused in any one place, determination of the population segments with the highest levels of infection will help to target the chemotherapeutic fight. To reinforce treatment with chemotherapeutic agents, tap water should be made available in all the localities of this area.

  6. Influence of Refrigeration and Formalin on the Floatability of Giardia duodenalis Cysts

    Maria da Luz Ribeiro Moitinho; Marta Bértoli; Terezinha Aparecida Guedes; Cláudio Santos Ferreira

    1999-01-01

    Giardia duodenalis cysts obtained from fresh fecal samples, fecal samples kept under refrigeration and fecal samples treated with formalin were studied as to their floatability on sucrose solutions with the following specific gravities: 1,040 kg/m3; 1,050 kg/m3; 1,060 kg/m3; 1,070 kg/m3; 1,080 kg/m3; 1,090 kg/m3; 1,100 kgm3; 1,150 kg/m3; 1,200 kg/m3; and 1,250 kg/m3, contained within counting-chambers 0.17 mm high. Cysts that floated on and those settled down as sediments were counted, and ha...

  7. Simultaneous detection and differentiation of Entamoeba histolytica, E. dispar, E. moshkovskii, Giardia lamblia and Cryptosporidium spp. in human fecal samples using multiplex PCR and qPCR-MCA.

    Zebardast, Nozhat; Yeganeh, Farshid; Gharavi, Mohammad Javad; Abadi, Alireza; Seyyed Tabaei, Seyyed Javad; Haghighi, Ali

    2016-10-01

    Entamoeba histolytica, Giardia lamblia and Cryptosporidium spp. are common causes of diarrheal and intestinal diseases all over the world. Microscopic methods are useful in the diagnosis of intestinal parasites (IPs), but their sensitivity was assessed approximately 60 percent. Recently, molecular techniques have been used increasingly for the identification and characterization of the parasites. Among those, in this study we have used multiplex PCR and Real-time PCR with melting curve analysis (qPCR-MCA) for simultaneous detection and differentiation of E. histolytica, E. dispar, E. moshkovskii, G. lamblia and Cryptosporidium spp. in human fecal samples. Twenty DNA samples from 12 E. histolytica and 8 E. dispar samples and twenty stool samples confirmed positive for G. lamblia and Cryptosporidium spp. were analyzed. After DNA extraction from the samples, multiplex PCR was done for detection and differentiation of above mentioned parasites. QPCR-MCA was also performed for the detection and differentiation of 11 isolates of above mentioned parasite in a cycle with a time and temperature. Multiplex PCR was able to simultaneous detect and differentiate of above mentioned parasite in a single reaction. QPCR-MCA was able to differentiate genus and species those five protozoa using melting temperature simultaneously at the same time and temperature programs. In total, qPCR-MCA diagnosed 7/11 isolation of E. histolytica, 6/8 isolation of E. dispar, 1/1 E. moshkovskii Laredo, 10/11 G. Lamblia and 6/11 Cryptosporidium spp. Application of multiplex PCR for detection of more than one species in a test in developing countries, at least in reference laboratories has accurate diagnosis and plays a critical role in differentiation of protozoan species. Multiplex PCR assay with a template and multi template had different results and it seems that using a set of primers with one template has higher diagnostic capability in compare with multi template. The results of this study

  8. Freqüencia da infecção por Giardia lamblia (Kunstler, 1882) em cães (Canis familiaris) avaliada pelo Método de Faust e cols. (1939) e pela Coloração da Auramina, no município de Canoas, RS, Brasil Frequence of infection by Giardia lamblia (Kunstler, 1882) in dogs (Canis familiaris) available trough the Faust and Collaborators Method (1939) and Auramine Staining in Canoas, RS, Brazil

    Cristiane Beck; Flávio Antônio Pacheco de Araújo; Adriana Tarnowski Olicheski; Adriana Schneider Breyer

    2005-01-01

    Giardia lamblia é um protozoário que acomete mais comumente animais jovens e que convivem em grupos. Apesar da alta prevalência, nem todos os animais apresentam a forma clínica da doença. Mesmo assim, a giardíase tem importância epidemiológica por possuir um elevado potencial zoonótico. O presente estudo teve como objetivo determinar a freqüência de Giardia lamblia em cães no município de Canoas, RS, Brasil, através do Método de Faust e cols. (1939) e da Técnica de Coloração da Auramina. Os g...

  9. ETV STATEMENT - PHYSICAL REMOVAL OF CRYPTOSPORIDIUM OOCYSTS AND GIARDIA CYSTS IN DRINKING WATER - ZENON ZEEWEED ZW500 ULTRAFILTRATION MEMBRANE SYSTEM AT PITTSBURGH, PA

    Verification testing of the ZENON Environmental Inc. ZeeWeed ZW500 UF Drinking Water System was conducted from 2/6-3/7/99. The treatment system underwent Giardia and Cryptosporidium removal challenge testing on 3/2/99 and demonstrated a 5.3 log10 removal of Giardia cysts and a 6...

  10. PCR DETECTION OF GIARDIA LAMBLIA BY TIM GENE AMPLIFICATION%用PCR扩增tim基因检测蓝氏贾第鞭毛虫

    丁慧萍; 卢思奇; 戎煜; 李凤舞; 王凤云

    2002-01-01

    采用聚合酶链反应(PCR)对蓝氏贾第鞭毛虫(Giardia lamblia)的磷酸丙糖异构酶(triose phosphate isomerase,缩写为tim)基因进行特异性扩增,结果扩增出1条683bp的DNA片段.此方法的特异性可高达100%,而其它DNA样本,如日本血吸虫(Schistosoma japonicum)、刚地弓形虫(Toxoplasma gondii)、微小隐孢子虫(Cryptosporidium parvum)、溶组织内阿米巴(Entamoeba histolytica)、旋毛虫(Trichinella spiralis)和阴道毛滴虫(Trichomonas vaginalis),以及人体血细胞等均未出现扩增反应.本法的敏感性也很高,可检测到0.4pg贾第虫包囊的DNA.13株来自不同地理位置和/或宿主的贾第虫DNA样本在PCR中均各产生1条长为683bp的目的片段.上述结果表明本实验建立的检测贾第虫的PCR方法有效.

  11. Occurence of Giardia lamblia in children of municipal day-care centers from Botucatu, São Paulo State, Brazil Ocorrência de Giardia lamblia em crianças atendidas em creches municipais de Botucatu, Estado de São Paulo, Brasil

    Semíramis Guimarães

    1995-12-01

    crianças examinadas, 93 (63,3% apresentaram cistos de G. lamblia nas fezes. Apenas 1 funcionário foi positivo para G. lamblia. O uso de 3 amostras de fezes aumentou a positividade do exame para o diagnóstico deste parasita, uma vez que dos 93 casos positivos, 24 (25,5% e 8 (8,5% foram diagnosticados somente após exame da segunda e terceira amostras, respectivamente. Outros parasitas e comensais intestinais como Ascaris lumbricoides (20,4%, Trichuris trichiura (19,0%, Hymenolepis nana (8,8%, Entamoeba coli (22,4% e Blastocystis hominis (32,0% foram diagnosticados. A análise estatística revelou não haver associação entre localização das creches, sexo e a frequência de infecção por G. lamblia. As porcentagens mais altas de infecção por Giardia foram observadas entre as crianças com idade variando de 1 a 4 anos.

  12. Strategies To Discover the Structural Components of Cyst and Oocyst Walls

    Samuelson, John; Bushkin, G. Guy; Chatterjee, Aparajita; Robbins, Phillips W.

    2013-01-01

    Cysts of Giardia lamblia and Entamoeba histolytica and oocysts of Toxoplasma gondii and Cryptosporidium parvum are the infectious and sometimes diagnostic forms of these parasites. To discover the structural components of cyst and oocyst walls, we have developed strategies based upon a few simple assumptions. Briefly, the most abundant wall proteins are identified by monoclonal antibodies or mass spectrometry. Structural components include a sugar polysaccharide (chitin for Entamoeba, β-1,3-l...

  13. Occurrence of Giardia cysts and Cryptosporidium oocysts in sewage and their reduction in treatment process; Gesuichu no Giardia shisuto oyobi Cryptosporidium oshisuto noudo to gesui syori ni okeru jyokyosei

    Hashimoto, A.; Hirata, T. [Azabu University, Kanagawa (Japan); Magara, Y. [National Institute of Public Health, Tokyo (Japan); Ogaki, S. [The University of Tokyo, Tokyo (Japan)

    1997-06-10

    Recently, the water system infection owing to protozoan, virus and so on which is different from the conventional infection like represented by bacteria, is reported. There are few examples for the infection conditional study and epidemiological investigation of these protozoan and virus in Japan. Authors carried out a field survey at nine sewage treatment plants, in order to investigate the occurrence of Giardia cysts and Cryptosporidium oocysts in raw sewage and the removal in sewage treatment processes. As a result, in all plants, Giardia cysts were detected in raw sewage and effluent of primary sedimentation. Cryptosporidium oocysts were detected from only one raw sewage sample. Indicator bacteria counts tested, C.perfringens spores, coliforms and E.coli, were statistically correlated with Giardia cyst densities and the most significant relationship was observed between C.perfringens spore counts and Giardia cyst densities. It was found that turbidity was the most appropriate indicator for Giardia cyst removal in activated sludge treatment process. 18 refs., 6 figs., 2 tabs.

  14. Development and evaluation of an off-the-slide genotyping technique for identifying Giardia cysts and Cryptosporidium oocysts directly from US EPA Method 1623 slides

    ABSTRACT Aims This study developed and systematically evaluated performance and limit of detection of an off-the-slide genotyping procedure for both Cryptosporidium oocysts and Giardia cysts. Methods and Results Slide standards containing flow sorted (oo)cysts were used to e...

  15. 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

    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.

  16. Genome Sequencing of Giardia lamblia Genotypes A2 and B Isolates (DH and GS) and Comparative Analysis with the Genomes of Genotypes A1 and E (WB and Pig)

    Adam, Rodney D.; Dahlstrom, Eric W.; Martens, Craig A.; Bruno, Daniel P.; Barbian, Kent D.; Ricklefs, Stacy M.; Hernandez, Matthew M.; Narla, Nirmala P.; Patel, Rima B.; Porcella, Stephen F.; Nash, Theodore E.

    2013-01-01

    Giardia lamblia (syn G. intestinalis, G. duodenalis) is the most common pathogenic intestinal parasite of humans worldwide and is a frequent cause of endemic and epidemic diarrhea. G. lamblia is divided into eight genotypes (A–H) which infect a wide range of mammals and humans, but human infections are caused by Genotypes A and B. To unambiguously determine the relationship among genotypes, we sequenced GS and DH (Genotypes B and A2) to high depth coverage and compared the assemblies with the nearly completed WB genome and draft sequencing surveys of Genotypes E (P15; pig isolate) and B (GS; human isolate). Our results identified DH as the smallest Giardia genome sequenced to date, while GS is the largest. Our open reading frame analyses and phylogenetic analyses showed that GS was more distant from the other three genomes than any of the other three were from each other. Whole-genome comparisons of DH_A2 and GS_B with the optically mapped WB_A1 demonstrated substantial synteny across all five chromosomes but also included a number of rearrangements, inversions, and chromosomal translocations that were more common toward the chromosome ends. However, the WB_A1/GS_B alignment demonstrated only about 70% sequence identity across the syntenic regions. Our findings add to information presented in previous reports suggesting that GS is a different species of Giardia as supported by the degree of genomic diversity, coding capacity, heterozygosity, phylogenetic distance, and known biological differences from WB_A1 and other G. lamblia genotypes. PMID:24307482

  17. Infectivity of Giardia duodenalis Cysts from UV Light-Disinfected Wastewater Effluent Using a Nude BALB/c Mouse Model

    dos Santos, Luciana Urbano; Alves, Delma Pegolo; Guaraldo, Ana Maria Aparecida; Cantusio Neto, Romeu; Durigan, Mauricio; Franco, Regina Maura Bueno

    2013-01-01

    Giardia duodenalis is a protozoan of public health interest that causes gastroenteritis in humans and other animals. In the city of Campinas in southeast Brazil, giardiasis is endemic, and this pathogen is detected at high concentrations in wastewater effluents, which are potential reservoirs for transmission. The Samambaia wastewater treatment plant (WWTP) in the city of Campinas employs an activated sludge system for sewage treatment and ultraviolet (UV) light for disinfection of effluents. To evaluate this disinfection process with respect to inactivating G. duodenalis cysts, two sample types were investigated: (i) effluent without UV disinfection (EFL) and (ii) effluent with UV disinfection (EFL+UV). Nude immunodeficient BALB/c mice were intragastrically inoculated with a mean dose of 14 cysts of G. duodenalis recovered from effluent from this WWTP, EFL, or EFL+UV. All animals inoculated with G. duodenalis cysts developed the infection, but animals inoculated with UV-exposed cysts released a lower average concentration of cysts in their faeces than animals inoculated with cysts that were not UV disinfected. Trophozoites were also observed in both groups of animals. These findings suggest that G. duodenalis cysts exposed to UV light were damaged but were still able to cause infection.

  18. Impacto de la dieta sobre la inducción de infección con quistes de Giardia lamblia en ratas Sprague-Dawley The effect of malnourishment on the development of giardiosis in Sprague-Dawley rats

    Martha Elvia Díaz-Cinco; Martha Nydia Ballesteros-Vázquez; Rosalba Pérez-Morales; Verónica Mata-Haro

    2002-01-01

    Objetivo. Evaluar el efecto de la desnutrición en la inducción de la giardiosis con diferentes concentraciones de quistes de Giardia lamblia utilizando como modelo animal ratas Sprague-Dawley. Material y métodos. Es un estudio experimental efectuado entre 1995 y 1999, en el Centro de Investigación en Alimentación y Desarrollo, de la ciudad de Hermosillo, estado de Sonora, México, y cuya muestra estuvo integrada por dos grupos de 6 a 8 unidades experimentales, las cuales recibieron dos tipos d...

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

    Núñez Fidel Ángel; López Jorge Luis; de la Cruz Ana Margarita; Finlay Carlos M.

    2003-01-01

    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 a...

  20. Apo And Calcium-Bound Crystal Structures of Alpha-11 Giardin, An Unusual Annexin From 'Giardia Lamblia'

    Pathuri, P.; Nguyen, E.T.; Svard, S.G.; Luecke, H.; /UC, Irvine /Uppsala U. /Karolinska Inst.

    2007-07-12

    Alpha-11 giardin is a member of the multi-gene alpha-giardin family in the intestinal protozoan, Giardia lamblia. This gene family shares an ancestry with the annexin super family, whose common characteristic is calcium-dependent binding to membranes that contain acidic phospholipids. Several alpha giardins are highly expressed during parasite-induced diarrhea in humans. Despite being a member of a large family of proteins, little is known about the function and cellular localization of alpha-11 giardin, although giardins are often associated with the cytoskeleton. It has been shown that Giardia exhibits high levels of alpha-11 giardin mRNA transcript throughout its life cycle; however, constitutive over-expression of this protein is lethal to the parasite. Determining the three-dimensional structure of an alpha-giardin is essential to identifying functional domains shared in the alpha-giardin family. Here we report the crystal structures of the apo and Ca{sup 2+}-bound forms of alpha-11 giardin, the first alpha giardin to be characterized structurally. Crystals of apo and Ca{sup 2+}-bound alpha-11 giardin diffracted to 1.1 angstroms and 2.93 angstroms, respectively. The crystal structure of selenium-substituted apo alpha-11 giardin reveals a planar array of four tandem repeats of predominantly {alpha}-helical domains, reminiscent of previously determined annexin structures, making this the highest-resolution structure of an annexin to date. The apo alpha-11 giardin structure also reveals a hydrophobic core formed between repeats I/IV and II/III, a region typically hydrophilic in other annexins. Surprisingly, the Ca{sup 2+}-bound structure contains only a single calcium ion, located in the DE loop of repeat I and coordinated differently from the two types of calcium sites observed in previous annexin structures. The apo and Ca{sup 2+}-bound alpha-11 giardin structures assume overall similar conformations; however, Ca2+-bound alpha-11 giardin crystallized in a lower

  1. 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

    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.

  2. 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

    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

  3. Research Progress on the Mechanisms of Antigenic Variation in Giardia lamblia%蓝氏贾第鞭毛虫表面抗原变异机制研究进展

    冯宪敏; 王月华; 鞠晓红

    2012-01-01

    蓝氏贾第鞭毛虫(Giardia lamblia,简称贾第虫)是引起腹泻的最常见的肠道寄生原虫之一.同大多数肠道寄生的病原体一样,表面抗原(variant-specific surface proteins,VSPs)变异是虫体逃避宿主免疫攻击的重要机制,从而导致疾病慢性化和/或重复感染的发生.本文将从基因水平的调控、转录和转录后调控、VSPs表达修饰调节和VSPs的加工、处理与转运等4个方面对贾第虫表面抗原变异机制的研究进展进行综述.%The intestinal protozoan parasite Giardia lamblia is one of the most common causes of diarrhoea and undergoes antigenic variation. In pathogenic microorganisms, antigenic variation is often described as a mechanism to evade the host immune system, resulting in chronic and/or recurrent infections. In the recent years, significant advances in the knowledge of the antigen switching process have been achieved. Here we review the principal knowledge on the mechanisms that regulate this process, including genomic organization, post-tanscriptional gene silencing, expressional modifications, and processing and turnover of VSPs.

  4. Detection of Giardia cysts with a cDNA probe and applications to water samples.

    Abbaszadegan, M; Gerba, C P; Rose, J B

    1991-01-01

    Giardiasis is the most common human parasite infection in the United States, causing a lengthy course of diarrhea. Transmission of Giardia species is by the fecal-oral route, and numerous waterborne outbreaks have been documented. The Environmental Protection Agency has regulated Giardia species in drinking water through the Surface Water Treatment Rule. Current methods for detection of Giardia species in water rely primarily on microscopic observation of water concentrates with immunofluores...

  5. 基于TPI基因的城市污水中蓝氏贾第鞭毛虫的分子鉴定%Molecular identification of Giardia lamblia isolates from raw urban wastewater using the TPI gene

    张唯哲; 凌虹; 张晓丽; 李懿宏; 姬红; 杨凤坤; 沈玉娟; 刘爱芹

    2012-01-01

    目的 对哈尔滨市污水处理厂原水中的蓝氏贾第鞭毛虫进行分子鉴定.方法 收集哈尔滨市污水处理厂原水样,提取基因组DNA,巢式PCR扩增蓝氏贾第鞭毛虫TPI基因,通过序列分析确定蓝氏贾第鞭毛虫的集聚体类型和亚型,并进行同源性分析.结果 从哈尔滨市污水处理厂原水DNA提取物中扩增出蓝氏贾第鞭毛虫TPI基因,经分子鉴定为蓝氏贾第鞭毛虫集聚体AⅡ,其序列与文献报道人源蓝氏贾第鞭毛虫集聚体AII序列(AB516351,FJ560570,EF688021)的同源性为100%.结论 哈尔滨市污水处理厂原水中存在蓝氏贾第鞭毛虫集聚体AII,威胁当地居民健康.%Objective To molecularly identify Giardia lamblia isolates from raw urban wastewater at a wastewater treatment plant in Haerbin. Methods Genomic DNA of G. lamblia was extracted and the TPI gene was amplified by nested PCRj the assemblage/genotype and sub-assemblage/subtype of C lamblia were identified and sequenced. The ho-mology of the gene was analyzed with reference nucleotide sequences downloaded from GenBank. Results The TPI gene of G. lamblia was amplified from DNA extracts prepared from raw wastewater from a wastewater treatment plant in Harbin, and the isolate was identified as assemblage AH. The obtained sequence based on TPI had 100% homology with the previously reported sequences of human-derived G. lamblia assemblage All (AB516351 ;FJ560570;EF688021). Conclusion The presence of G. lamblia assemblage All in raw urban wastewater in Harbin poses a threat to the health of local inhabitants.

  6. Comparative Analysis of the 15.5kD Box C/D snoRNP Core Protein in the Primitive Eukaryote Giardia lamblia Reveals Unique Structural and Functional Features

    Biswas, Shyamasri; Buhrman, Greg; Gagnon, Keith; Mattos, Carla; Brown, II, Bernard A.; Maxwell, E. Stuart (NCSU); (UTSMC)

    2012-07-11

    Box C/D ribonucleoproteins (RNP) guide the 2'-O-methylation of targeted nucleotides in archaeal and eukaryotic rRNAs. The archaeal L7Ae and eukaryotic 15.5kD box C/D RNP core protein homologues initiate RNP assembly by recognizing kink-turn (K-turn) motifs. The crystal structure of the 15.5kD core protein from the primitive eukaryote Giardia lamblia is described here to a resolution of 1.8 {angstrom}. The Giardia 15.5kD protein exhibits the typical {alpha}-{beta}-{alpha} sandwich fold exhibited by both archaeal L7Ae and eukaryotic 15.5kD proteins. Characteristic of eukaryotic homologues, the Giardia 15.5kD protein binds the K-turn motif but not the variant K-loop motif. The highly conserved residues of loop 9, critical for RNA binding, also exhibit conformations similar to those of the human 15.5kD protein when bound to the K-turn motif. However, comparative sequence analysis indicated a distinct evolutionary position between Archaea and Eukarya. Indeed, assessment of the Giardia 15.5kD protein in denaturing experiments demonstrated an intermediate stability in protein structure when compared with that of the eukaryotic mouse 15.5kD and archaeal Methanocaldococcus jannaschii L7Ae proteins. Most notable was the ability of the Giardia 15.5kD protein to assemble in vitro a catalytically active chimeric box C/D RNP utilizing the archaeal M. jannaschii Nop56/58 and fibrillarin core proteins. In contrast, a catalytically competent chimeric RNP could not be assembled using the mouse 15.5kD protein. Collectively, these analyses suggest that the G. lamblia 15.5kD protein occupies a unique position in the evolution of this box C/D RNP core protein retaining structural and functional features characteristic of both archaeal L7Ae and higher eukaryotic 15.5kD homologues.

  7. COMPARISON OF DIRECT IMMUNOFLUORESCENCE, IODINE-SAL INE WET MOUNT AND MODIFIED ACID FAST STAINING METHODS F OR DETECTION OF CRYPTOSPORIDIUM AND GIARDIA SPP. IN HU MAN FECAL SPECIMENS

    Prakriti

    2012-10-01

    Full Text Available ABSTRACT: BACKGROUND: Cryptosporidiosis and Giardiasis are leading causes o f parasitic intestinal diseases. There are various methods to d etect them including iodine-saline wet mount for Giardia, Modified Acid fast (MAF staining for Cryptosporidia and Direct Fluorescent Antigen detection (DFA method. OBJECTIVES: This study was conducted to compare three methods f or the detection of Cryptosporidium oocysts and Giardia cysts in fecal s amples. METHOD: 44 stool specimens from patients with history of diarrhea were examined for Giardia lamblia and Cryptosporidium parvum by using a direct immunofluores cent-monoclonal antibody stain (for unspun specimens, Iodine- saline wet mount method fo r Giardia cysts & trophozoites and Modified acid-fast for Cryptosporidium oocysts. RESULTS: From the total of 44 specimens; 29 (65.9 % Cryptosporidia oocysts were isolated and 6 ( 13.6% Giardia cysts by all the Iodine- Saline wet mount, MAF, DFA methods. The direct immu nofluorescent-monoclonal antibody method resulted in a significantly increased detect ion of both Giardia cysts (5 versus 1 specimens, p value =0.01 and Cryptosporidium oocysts ( 19 versus 10 specimens, p value=0.01. CONCLUSIONS: DFA is a sensitive method for detection of Cryptospo ridium oocysts and Giardia cysts in fecal samples whereas M AF is a reliable screening method.

  8. Immunolocalization of Delta-Giardin within the Ventral Disc in of Trophozoites and in cysts of Giardia duodenalis using the Multiplex Laser Scanning Confocal Microscopy

    Immunolocalization of alpha2-, beta- and delta-giardin in Giardia showed that in the trophozoites and cysts delta-giardin it strictly associated with the ventral disc. Optical sectioning of the ventral discs, together with quantitative colocalization of the immunoreactivity for delta- and beta-giard...

  9. 实时荧光PCR检测蓝氏贾第鞭毛虫和隐孢子虫方法的建立%Detection of Giardia lamblia and Cryptosporidium by the real-time PCR method

    杨晓华; 侯炎昌

    2013-01-01

    目的 建立贾第鞭毛虫和隐孢子虫的基因检测方法.方法 根据GenBank中贾第鞭毛虫和隐孢子虫相对保守序列,设计引物及其相应的Taqman探针.通过对引物和探针浓度、Taq酶以及反应条件等优化筛选后,建立检测贾第鞭毛虫和隐孢子虫的荧光PCR方法.结果 贾第鞭毛虫和隐孢子虫的检测结果为阳性,对其它DNA样本如日本血吸虫、刚地弓形虫、溶组织内阿米巴、旋毛虫和阴道毛滴虫的检测均为阴性.本法的敏感性高,可检测到10~102copies/μl的DNA浓度.结论 建立的基因检测方法,对贾第鞭毛虫和隐孢子虫的检测具有高度的特异性和敏感性,可用于饮用水和临床样本等的快速检测.%Objeetive The present study aims to establish a real-time PCR method for the detection of Giardia lamblia and Cryptosporidium.Methods Specific primers and the corresponding Taqman probes were designed according to the conserved sequences recorded in GenBank.Results Using the designed primers and probes,positive results were obtained from the samples of Giardia lamblia and Cryptosporidium.Non-specific detection of other DNA samples,such as Schistosoma japonicum,Toxoplasma gondii,Entamoeba histolytica,Trichinella spiralis and Trichomonas vaginalis was not observed.The sensitivity of this method is 10 ~ 102 copies/μl.Conclusion The established method is specific and sensitive for the detection of Giardia lamblia and Cryptosporidium.This method could be used in the rapid detection of drinking water and clinical samples.

  10. Development of monoclonal antibodies specifically recognizing the cyst stage of Entamoeba histolytica.

    Walderich, B; Burchard, G D; Knobloch, J; Müller, L

    1998-09-01

    Protozoan cysts were isolated according to a two-step sucrose gradient procedure. Pure cysts of Entamoeba histolytica, in fixed and native states, were injected into BALB/c mice intraperitoneally for immunization. The spleens of these animals were used for fusion with AG8 mouse myeloma cells. Hybridomas were obtained and tested for the recognition of E. histolytica, E. dispar, E. coli, E. hartmanni, Endolimax nana, Jodamoeba biitschlii, and Giardia lamblia. Three monoclonal antibodies were identified that reacted only with cysts and trophozoites of E. histolytica. These can be used for differentiation and identification of E. histolytica in feces. PMID:9749623