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Sample records for construct improves anti-parasite

  1. Dual anti-inflammatory and anti-parasitic action of topical ivermectin 1% in papulopustular rosacea.

    Science.gov (United States)

    Schaller, M; Gonser, L; Belge, K; Braunsdorf, C; Nordin, R; Scheu, A; Borelli, C

    2017-11-01

    Recently, therapy of rosacea with inflammatory lesions (papulopustular) has improved substantially with the approval of topical ivermectin 1% cream. It is assumed to have a dual mode of action with anti-inflammatory capacities and anti-parasitic effects against Demodex, which however has not yet been demonstrated in vivo. To find scientific rationale for the dual anti-inflammatory and anti-parasitic mode of action of topical ivermectin 1% cream in patients with rosacea. A monocentric pilot study was performed including 20 caucasion patients with moderate to severe rosacea, as assessed by investigator global assessment (IGA score ≥3) and a Demodex density ≥15/cm 2 . Patients were treated with topical ivermectin 1% cream once daily (Soolantra ® ) for ≥12 weeks. The density of Demodex mites was assessed with skin surface biopsies. Expression of inflammatory and immune markers was evaluated with RT-PCR and by immunofluorescence staining. The mean density of mites was significantly decreased at week 6 and week 12 (P < 0.001). The gene expression levels of IL-8, LL-37, HBD3, TLR4 and TNF-α were downregulated at both time points. Reductions in gene expression were significant for LL-37, HBD3 and TNF-α at both follow-up time points and at week 12 for TLR4 (all P < 0.05). Reduced LL-37 expression (P < 0.05) and IL-8 expression were confirmed on the protein level by immunofluorescence staining. All patients improved clinically, and 16 of 20 patients reached therapeutic success defined as IGA score ≤1. Topical ivermectin 1% cream acts by a dual, anti-inflammatory and anti-parasitic mode of action against rosacea by killing Demodex spp. in vivo, in addition to significantly improving clinical signs and symptoms in the skin. © 2017 European Academy of Dermatology and Venereology.

  2. Medicinal Plants: A Source of Anti-Parasitic Secondary Metabolites

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    Michael Wink

    2012-10-01

    Full Text Available This review summarizes human infections caused by endoparasites, including protozoa, nematodes, trematodes, and cestodes, which affect more than 30% of the human population, and medicinal plants of potential use in their treatment. Because vaccinations do not work in most instances and the parasites have sometimes become resistant to the available synthetic therapeutics, it is important to search for alternative sources of anti-parasitic drugs. Plants produce a high diversity of secondary metabolites with interesting biological activities, such as cytotoxic, anti-parasitic and anti-microbial properties. These drugs often interfere with central targets in parasites, such as DNA (intercalation, alkylation, membrane integrity, microtubules and neuronal signal transduction. Plant extracts and isolated secondary metabolites which can inhibit protozoan parasites, such as Plasmodium, Trypanosoma, Leishmania, Trichomonas and intestinal worms are discussed. The identified plants and compounds offer a chance to develop new drugs against parasitic diseases. Most of them need to be tested in more detail, especially in animal models and if successful, in clinical trials.

  3. Anti-parasitic effects of plant secondary metabolites on swine nematodes

    DEFF Research Database (Denmark)

    Williams, A.R.; Pena-Espinoza, Miguel Angel; Fryganas, Christos

    Organic production presents challenges to animal health and productivity. In organic pig production, animals must have access to outdoor pastures which increases exposure to gastrointestinal parasites. Moreover, the routine use of synthetic anti-parasitic drugs is not allowed. Thus, novel parasite...

  4. The effectiveness of empirical anti-parasitic treatment in returning travellers with persistent abdominal symptoms.

    Science.gov (United States)

    Nissan, Batel; Lachish, Tamar; Schwartz, Eli

    2018-01-01

    Persistent abdominal symptoms (PAS) are common among returning-travellers. In the absence of sensitive tests to identify intestinal parasites, gastrointestinal (GI) symptoms often remain a diagnostic challenge. In this study we examined the effectiveness of empirical anti-parasitic treatment in returning-travellers with PAS despite no positive stool-test. A retrospective study among returning travellers who approached the clinic between the years 2014 and 2016 with GI complaints without a positive stool-test. The empirical treatment included broad-spectrum anti-parasitic agents-oral Tinidazole and Albendazole. A follow-up questionnaire was performed at least 6 months post-treatment. A total of 102 patients responded the questionnaire-50% women; average age 31.14 (±12.20) years. The average duration of complaints before treatment was 16.52 (±30.06) months. Common GI symptoms included abdominal pain (83.3%) and diarrhoea (78.4%); 67.6% of the patients complained of extreme fatigue. Overall, 69% of the patients reported an improvement in GI symptoms, 37% of them reported full recovery within a few weeks post-treatment. Furthermore, there was an improvement in the energy level and general well-being in 68% and 70% of the patients, respectively. Only 33% of the patients reported minor side effects related to the treatment. The improvement in GI symptoms, energy level and general well-being shortly after anti-parasitic treatment justifies this empirical approach in returning-travellers with PAS despite negative stool-tests. The association between fatigue and PAS post-travel and the improvement in both as a response to treatment defines fatigue as part of a new syndrome-'Post-travel fatigue and abdominal symptoms'. © International Society of Travel Medicine, 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

  5. Identifying rapidly parasiticidal anti-malarial drugs using a simple and reliable in vitro parasite viability fast assay.

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    Linares, María; Viera, Sara; Crespo, Benigno; Franco, Virginia; Gómez-Lorenzo, María G; Jiménez-Díaz, María Belén; Angulo-Barturen, Íñigo; Sanz, Laura María; Gamo, Francisco-Javier

    2015-11-05

    The emergence of Plasmodium falciparum resistance to artemisinins threatens to undermine the effectiveness of artemisinin-based combination anti-malarial therapy. Developing suitable drugs to replace artemisinins requires the identification of new compounds that display rapid parasite killing kinetics. However, no current methods fully meet the requirements to screen large compound libraries for candidates with such properties. This study describes the development and validation of an in vitro parasite viability fast assay for identifying rapidly parasiticidal anti-malarial drugs. Parasite killing kinetics were determined by first culturing unlabelled erythrocytes with P. falciparum in the presence of anti-malarial drugs for 24 or 48 h. After removing the drug, samples were added to erythrocytes pre-labelled with intracellular dye to allow their subsequent identification. The ability of viable parasites to re-establish infection in labelled erythrocytes could then be detected by two-colour flow cytometry after tagging of parasite DNA. Thus, double-stained erythrocytes (with the pre-labelled intracellular dye and the parasite DNA dye) result only after establishment of new infections by surviving parasites. The capacity of the test anti-malarial drugs to eliminate viable parasites within 24 or 48 h could, therefore, be determined. The parasite viability fast assay could be completed within 48 h following drug treatment and distinguished between rapidly parasiticidal anti-malarial drugs versus those acting more slowly. The assay was validated against ten standard anti-malarial agents with known properties and results correlated well with established methods. An abbreviated assay, suitable for adaption to medium-high throughput screening, was validated and applied against a set of 20 compounds retrieved from the publically available Medicines for Malaria Venture 'Malaria Box'. The quantification of new infections to determine parasite viability offers important

  6. Effect of Anti-Parasite Chemotherapeutic Agents on Immune Reactions.

    Science.gov (United States)

    1980-08-01

    observations). Similar effects of a number of other alkylating agents have been noticed (9, and personal observa- tions). Similarly, corticosteroids inhibit...Wellham, L. L., and Sigel, M. M. Ef- fect of anti-cancer chemotherapeutic agents on immune reactions of mice. I. Comparison of two nitrosoureas . J...7 D-Ri138 852 EFFECT OF ANTI-PARASITE CHEMOTHERAPEUTIC AGENTS ON i/i IMMUNE REACTIONS(U) SOUTH CAROLINA UNIV COLUMBIA DEPT OF MICROBIOLOGY AND

  7. Profiling the anti-protozoal activity of anti-cancer HDAC inhibitors against Plasmodium and Trypanosoma parasites.

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    Engel, Jessica A; Jones, Amy J; Avery, Vicky M; Sumanadasa, Subathdrage D M; Ng, Susanna S; Fairlie, David P; Skinner-Adams, Tina; Andrews, Katherine T

    2015-12-01

    Histone deacetylase (HDAC) enzymes work together with histone acetyltransferases (HATs) to reversibly acetylate both histone and non-histone proteins. As a result, these enzymes are involved in regulating chromatin structure and gene expression as well as other important cellular processes. HDACs are validated drug targets for some types of cancer, with four HDAC inhibitors clinically approved. However, they are also showing promise as novel drug targets for other indications, including malaria and other parasitic diseases. In this study the in vitro activity of four anti-cancer HDAC inhibitors was examined against parasites that cause malaria and trypanosomiasis. Three of these inhibitors, suberoylanilide hydroxamic acid (SAHA; vorinostat(®)), romidepsin (Istodax(®)) and belinostat (Beleodaq(®)), are clinically approved for the treatment of T-cell lymphoma, while the fourth, panobinostat, has recently been approved for combination therapy use in certain patients with multiple myeloma. All HDAC inhibitors were found to inhibit the growth of asexual-stage Plasmodium falciparum malaria parasites in the nanomolar range (IC50 10-200 nM), while only romidepsin was active at sub-μM concentrations against bloodstream form Trypanosoma brucei brucei parasites (IC50 35 nM). The compounds were found to have some selectivity for malaria parasites compared with mammalian cells, but were not selective for trypanosome parasites versus mammalian cells. All compounds caused hyperacetylation of histone and non-histone proteins in P. falciparum asexual stage parasites and inhibited deacetylase activity in P. falciparum nuclear extracts in addition to recombinant PfHDAC1 activity. P. falciparum histone hyperacetylation data indicate that HDAC inhibitors may differentially affect the acetylation profiles of histone H3 and H4.

  8. Investigating anti-parasitic effects of plant secondary metabolites: effects on swine nematodes

    DEFF Research Database (Denmark)

    Williams, Andrew; Pena-Espinoza, Miguel Angel; Fryganas, Christos

    2014-01-01

    Organic and outdoor animal production presents challenges to animal health and productivity. In organic pig production, animals must have access to outdoor pastures which increases exposure to pathogens such as gastrointestinal nematodes. Moreover, the routine use of synthetic anti-parasitic drugs...

  9. Profiling the anti-protozoal activity of anti-cancer HDAC inhibitors against Plasmodium and Trypanosoma parasites

    Directory of Open Access Journals (Sweden)

    Jessica A. Engel

    2015-12-01

    Full Text Available Histone deacetylase (HDAC enzymes work together with histone acetyltransferases (HATs to reversibly acetylate both histone and non-histone proteins. As a result, these enzymes are involved in regulating chromatin structure and gene expression as well as other important cellular processes. HDACs are validated drug targets for some types of cancer, with four HDAC inhibitors clinically approved. However, they are also showing promise as novel drug targets for other indications, including malaria and other parasitic diseases. In this study the in vitro activity of four anti-cancer HDAC inhibitors was examined against parasites that cause malaria and trypanosomiasis. Three of these inhibitors, suberoylanilide hydroxamic acid (SAHA; vorinostat®, romidepsin (Istodax® and belinostat (Beleodaq®, are clinically approved for the treatment of T-cell lymphoma, while the fourth, panobinostat, has recently been approved for combination therapy use in certain patients with multiple myeloma. All HDAC inhibitors were found to inhibit the growth of asexual-stage Plasmodium falciparum malaria parasites in the nanomolar range (IC50 10–200 nM, while only romidepsin was active at sub-μM concentrations against bloodstream form Trypanosoma brucei brucei parasites (IC50 35 nM. The compounds were found to have some selectivity for malaria parasites compared with mammalian cells, but were not selective for trypanosome parasites versus mammalian cells. All compounds caused hyperacetylation of histone and non-histone proteins in P. falciparum asexual stage parasites and inhibited deacetylase activity in P. falciparum nuclear extracts in addition to recombinant PfHDAC1 activity. P. falciparum histone hyperacetylation data indicate that HDAC inhibitors may differentially affect the acetylation profiles of histone H3 and H4.

  10. Transgenic Expression of the Anti-parasitic Factor TEP1 in the Malaria Mosquito Anopheles gambiae.

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    Gloria Volohonsky

    2017-01-01

    Full Text Available Mosquitoes genetically engineered to be resistant to Plasmodium parasites represent a promising novel approach in the fight against malaria. The insect immune system itself is a source of anti-parasitic genes potentially exploitable for transgenic designs. The Anopheles gambiae thioester containing protein 1 (TEP1 is a potent anti-parasitic protein. TEP1 is secreted and circulates in the mosquito hemolymph, where its activated cleaved form binds and eliminates malaria parasites. Here we investigated whether TEP1 can be used to create malaria resistant mosquitoes. Using a GFP reporter transgene, we determined that the fat body is the main site of TEP1 expression. We generated transgenic mosquitoes that express TEP1r, a potent refractory allele of TEP1, in the fat body and examined the activity of the transgenic protein in wild-type or TEP1 mutant genetic backgrounds. Transgenic TEP1r rescued loss-of-function mutations, but did not increase parasite resistance in the presence of a wild-type susceptible allele. Consistent with previous reports, TEP1 protein expressed from the transgene in the fat body was taken up by hemocytes upon a challenge with injected bacteria. Furthermore, although maturation of transgenic TEP1 into the cleaved form was impaired in one of the TEP1 mutant lines, it was still sufficient to reduce parasite numbers and induce parasite melanization. We also report here the first use of Transcription Activator Like Effectors (TALEs in Anopheles gambiae to stimulate expression of endogenous TEP1. We found that artificial elevation of TEP1 expression remains moderate in vivo and that enhancement of endogenous TEP1 expression did not result in increased resistance to Plasmodium. Taken together, our results reveal the difficulty of artificially influencing TEP1-mediated Plasmodium resistance, and contribute to further our understanding of the molecular mechanisms underlying mosquito resistance to Plasmodium parasites.

  11. Occurrence of anti-Toxoplasma gondii antibodies and parasite DNA in backyard chicken breeding in Northeast, Brazil

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    Marcela Fernanda Torres Samico Fernandes

    2016-03-01

    Full Text Available Abstract The aim of the present study was to investigate the occurrence of anti-Toxoplasma gondii antibodies and parasite DNA in backyard chickens bred in the metropolitan area of Recife, Brazil. In total, 212 serum samples were collected from 16 properties, and 12 backyard chickens were collected in the six sanitary districts of Recife. An indirect immunofluorescence assay (IFA was used to investigate the occurrence of anti-Toxoplasma gondii antibodies. Polymerase chain reaction (PCR was used to detect T. gondii DNA in brain, heart, liver and lung specimens. Of the samples analyzed by serology, 86/212 (40.56% were positive; of the samples analyzed by PCR, 2/12 (16.7% were positive, with both samples positive by both tests (serological and molecular. The presence of antibody anti-T. gondii and parasite DNA in tissues of these animals are worrying aspects for public health because there is a risk of transmission of the parasite to humans through eating undercooked or raw meat. Based on the results, the adoption of preventive measures to prevent the cats access to the chickens creations should be encouraged, since these animals were identified in most of the studied properties.

  12. Tulbaghia violacea and Allium ursinum Extracts Exhibit Anti-Parasitic and Antimicrobial Activities.

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    Krstin, Sonja; Sobeh, Mansour; Braun, Markus Santhosh; Wink, Michael

    2018-02-02

    Garlic has played an important role in culinary arts and remedies in the traditional medicine throughout human history. Parasitic infections represent a burden in the society of especially poor countries, causing more than 1 billion infections every year and leading to around one million deaths. In this study, we investigated the mode of anti-parasitic activity of "wild garlics" Tulbaghia violacea and Allium ursinum dichloromethane extracts against parasites Trypanosoma brucei brucei and Leishmania tarentolae with regard to their already known antimicrobial activity. We also evaluated their cytotoxic potential against human cells. Both extracts showed a relevant trypanocidal and leishmanicidal activity, although L. tarentolae was less sensitive. We determined that the probable mode of action of both extracts is the irreversible inhibition of the activity of Trypanosoma brucei trypanothione reductase enzyme. The extracts showed a mild cytotoxic activity against human keratinocytes. They also exhibited weak-in most cases comparable-antibacterial and antifungal activity. HPLC-MS/MS analysis showed that both extracts are abundant in sulfur compounds. Thus, for the first time, the ability of Allium ursinum and Tulbaghia violacea to kill Trypanosoma sp. and Leishmania sp. parasites, probably by binding to and inactivating sulfur-containing compounds essential for the survival of the parasite, is shown.

  13. Tulbaghia violacea and Allium ursinum Extracts Exhibit Anti-Parasitic and Antimicrobial Activities

    Directory of Open Access Journals (Sweden)

    Sonja Krstin

    2018-02-01

    Full Text Available Garlic has played an important role in culinary arts and remedies in the traditional medicine throughout human history. Parasitic infections represent a burden in the society of especially poor countries, causing more than 1 billion infections every year and leading to around one million deaths. In this study, we investigated the mode of anti-parasitic activity of “wild garlics” Tulbaghia violacea and Allium ursinum dichloromethane extracts against parasites Trypanosoma brucei brucei and Leishmania tarentolae with regard to their already known antimicrobial activity. We also evaluated their cytotoxic potential against human cells. Both extracts showed a relevant trypanocidal and leishmanicidal activity, although L. tarentolae was less sensitive. We determined that the probable mode of action of both extracts is the irreversible inhibition of the activity of Trypanosoma brucei trypanothione reductase enzyme. The extracts showed a mild cytotoxic activity against human keratinocytes. They also exhibited weak—in most cases comparable—antibacterial and antifungal activity. HPLC-MS/MS analysis showed that both extracts are abundant in sulfur compounds. Thus, for the first time, the ability of Allium ursinum and Tulbaghia violacea to kill Trypanosoma sp. and Leishmania sp. parasites, probably by binding to and inactivating sulfur-containing compounds essential for the survival of the parasite, is shown.

  14. Recombinant anti-tenascin antibody constructs

    Energy Technology Data Exchange (ETDEWEB)

    ZALUTSKY, MICHAEL R

    2006-08-29

    The general objective of this research is to combine genetically derived molecular constructs reactive with tenascin, with appropriate radionuclides and labeling methods in order to generate more effective diagnostic and therapeutic reagents for oncologic nuclear medicine. Tenascin, a polymorphic extracellular matrix glycoprotein, is of interest because of its high expression on glioma, melanoma, as well as prostate and breast carcinoma. Recently, we have also documented high levels of tenascin in lymphomas, particularly those of higher grade, making the potential clinical impact of tenascin-specific radiodiagnostics and therapeutics even greater. An essential feature of our work plan is the ability to exploit our extensive clinical experience in order to design second-generation constructs with properties which could improve clinical efficacy. To date, we have treated over 150 brain tumor patients with 131I-labeled murine 81C6, an antibody which binds specifically to the alternatively spliced fibronectin type III repeats CD of the tenascin molecule. During the current grant period, we have made several observations which form the basis for our proposed specific aims. First, tissue distribution and catabolism experiments in animal models have demonstrated enhanced stability for a chimeric construct composed of murine variable regions and human IgG2 constant domains. Furthermore, pharmacokinetic studies in patients with 131I-labeled chimeric 81C6 have shown significantly longer retention in glioma tumor resection cavities compared with its murine parent. Second, we have initiated the first clinical trial of an endoradiotherapeutic labeled with the 7.2-hr -particle emitter 211At. Twelve glioma patients have received 211At-labeled chimeric 81C6 directly into their brain tumor resection cavity, and very encouraging results have been obtained. Now that the feasibility of human studies with 211At, has been demonstrated, the development and evaluation of anti

  15. Irradiation-atenuated anti-parasitic vaccines against helminthic infections in ruminants

    International Nuclear Information System (INIS)

    Alabay, M.

    1986-01-01

    The only commercially available irradiated vaccine is Dictol, the anti-Dictiyocaulus viviparus vaccine used in cattle. This succesful product has been in use for over 20 years. Irradiated vaccines have been applied to a number of different host-parasite systems and it has been shown that a high degree of protection can be conferred on the host by administration of radiation-attenuated larvae. In this paper, present situation of radiation attenuated vaccines against helminthic diseases of ruminants is reviewed. (author)

  16. A Plasmodium falciparum screening assay for anti-gametocyte drugs based on parasite lactate dehydrogenase detection

    NARCIS (Netherlands)

    D'Alessandro, S.; Silvestrini, F.; Dechering, K.; Corbett, Y.; Parapini, S.; Timmerman, M.; Galastri, L.; Basilico, N.; Sauerwein, R.; Alano, P.; Taramelli, D.

    2013-01-01

    OBJECTIVES: Plasmodium gametocytes, responsible for malaria parasite transmission from humans to mosquitoes, represent a crucial target for new antimalarial drugs to achieve malaria elimination/eradication. We developed a novel colorimetric screening method for anti-gametocyte compounds based on the

  17. Seroprevalence rates of antibodies againstLeishmania infantum and other protozoan and rickettsial parasites in dogs

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    Silvana de Cássia Paulan

    Full Text Available Canine visceral leishmaniasis (CVL is caused by the protozoan Leishmania infantum, which infects dogs and humans in many regions of Brazil. The present study involved an indirect fluorescent antibody test (IFAT to analyze L. infantum,Ehrlichia spp., Babesia canis,Toxoplasma gondii and Neospora caninuminfection rates in serum samples from 93 dogs in a rural settlement in Ilha Solteira, SP, Brazil. The seroprevalence rates of anti-L. infantum, anti-Ehrlichia, anti-B. canis, anti-T. gondii and anti-N. caninum antibodies were 37.6%, 75.3%, 72%, 47.3% and 6.4%, respectively. In addition to IFAT, direct microscopic examination of popliteal lymph node aspirates revealed 26.9% of CVL positive dogs. Serological tests revealed that 17.2% of the dogs were seropositive for a single parasite, 29% for two parasites, 33% for three, 16.1% for four, and 1.1% for five parasites, while 3.2% were seronegative for five parasites. The presence of antibodies against these parasites in serum samples from dogs confirmed their exposure to these parasites in this rural area. Because of the potential zoonotic risk of these diseases, mainly leishmaniasis, ehrlichiosis and toxoplasmosis, special attention should focus on programs for the improvement of diagnostic assays and control measures against these parasites.

  18. The effect of different screw-rod design on the anti-rotational torque: a biomechanical comparison of three conventional screw-rod constructs.

    Science.gov (United States)

    Huang, Zifang; Wang, Chongwen; Fan, Hengwei; Sui, Wenyuan; Li, Xueshi; Wang, Qifei; Yang, Junlin

    2017-07-28

    Screw-rod constructs have been widely used to correct spinal deformities, but the effects of different screw-rod systems on anti-rotational torque have not been determined. This study aimed to analyze the biomechanical effect of different rod-screw constructs on anti-rotational torque. Three conventional spinal screw-rod systems (Legacy, RF-F-10 and USSII) were used to test the anti-rotational torque in the material test machine. ANOVA was performed to evaluate the anti-rotational capacity of different pedicle screws-rod constructs. The anti-rotational torque of Legacy group, RF-F-10 group and USSII group were 12.3 ± 1.9 Nm, 6.8 ± 0.4 Nm, and 3.9 ± 0.8 Nm, with a P value lower than 0.05. This results indicated that the Legacy screws-rod construct could provide a highest anti-rotation capacity, which is 68% and 210% greater than RF-F-10 screw-rod construct and USSII screw-rod respectively. The anti-rotational torque may be mainly affected by screw cap and groove design. Our result showed the anti-rotational torque are: Legacy system > RF-F-10 system > USSII system, suggesting that appropriate rod-screw constructs selection in surgery may be vital for anti-rotational torque improvement and preventing derotation correction loss.

  19. Wesleyan (AntiFeminism: A Religious Construction of Gender Equality

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    Lisa Weaver Swartz

    2018-03-01

    Full Text Available Using ethnographic research and interviews, this article explored the construction of gender equality among students and faculty members at the Asbury Theological Seminary. The institution constructed an unusual blend of egalitarianism and anti-feminism using explicitly religious tools. Specifically, it was found that community members constructed firm commitments to gender equality from their heavily individualistic theology and from identification with the New Testament Church. The community’s resonance with feminism was also limited by evangelical anti-structuralism and an ethic of Christian humility and moderation. Established constructions of gender equality and inequality in established scholarly, and especially feminist, literature could not fully explain this unusual blend. This paper argues that agency and empowerment can be available to women because of the theological content of their religion.

  20. Irradiation-attenuated anti-parasite vaccines in ruminants. Present status and future prospects

    International Nuclear Information System (INIS)

    Taylor, M.G.

    1981-01-01

    The only commercially available irradiated anti-parasite vaccine is Dictol, the anti-Dictyocaulus viviparus vaccine, which is still being widely used in cattle 20 years after its introduction. Several other similar helminth vaccines which showed promise early in their development or use have now been abandoned for reasons both scientific and commercial. Nevertheless, there is still active interest in the development of irradiated vaccines for fascioliasis and schistosomiasis, as recent field trials have shown that irradiated metacercarial and schistosomular vaccines are effective against F. hepatica and S. bovis in cattle. There are no commercially available irradiated vaccines against protozoal diseases. Although experiments showed that irradiated vaccines were effective against Babesia bigemina and Theileria parva in cattle, interest in these has waned as other forms of live vaccines have been introduced. Vaccination against African trypanosomiasis remains an intractable problem, because of the multiplicity of naturally occurring antigenically distinct strains. (author)

  1. Protective Effect of Different Anti-Rabies Virus VHH Constructs against Rabies Disease in Mice

    Science.gov (United States)

    Terryn, Sanne; Francart, Aurélie; Lamoral, Sophie; Hultberg, Anna; Rommelaere, Heidi; Wittelsberger, Angela; Callewaert, Filip; Stohr, Thomas; Meerschaert, Kris; Ottevaere, Ingrid; Stortelers, Catelijne; Vanlandschoot, Peter; Kalai, Michael; Van Gucht, Steven

    2014-01-01

    Rabies virus causes lethal brain infection in about 61000 people per year. Each year, tens of thousands of people receive anti-rabies prophylaxis with plasma-derived immunoglobulins and vaccine soon after exposure. Anti-rabies immunoglobulins are however expensive and have limited availability. VHH are the smallest antigen-binding functional fragments of camelid heavy chain antibodies, also called Nanobodies. The therapeutic potential of anti-rabies VHH was examined in a mouse model using intranasal challenge with a lethal dose of rabies virus. Anti-rabies VHH were administered directly into the brain or systemically, by intraperitoneal injection, 24 hours after virus challenge. Anti-rabies VHH were able to significantly prolong survival or even completely rescue mice from disease. The therapeutic effect depended on the dose, affinity and brain and plasma half-life of the VHH construct. Increasing the affinity by combining two VHH with a glycine-serine linker into bivalent or biparatopic constructs, increased the neutralizing potency to the picomolar range. Upon direct intracerebral administration, a dose as low as 33 µg of the biparatopic Rab-E8/H7 was still able to establish an anti-rabies effect. The effect of systemic treatment was significantly improved by increasing the half-life of Rab-E8/H7 through linkage with a third VHH targeted against albumin. Intraperitoneal treatment with 1.5 mg (2505 IU, 1 ml) of anti-albumin Rab-E8/H7 prolonged the median survival time from 9 to 15 days and completely rescued 43% of mice. For comparison, intraperitoneal treatment with the highest available dose of human anti-rabies immunoglobulins (65 mg, 111 IU, 1 ml) only prolonged survival by 2 days, without rescue. Overall, the therapeutic benefit seemed well correlated with the time of brain exposure and the plasma half-life of the used VHH construct. These results, together with the ease-of-production and superior thermal stability, render anti-rabies VHH into valuable

  2. Anti-Leishmania activity of new ruthenium(II) complexes: Effect on parasite-host interaction.

    Science.gov (United States)

    Costa, Mônica S; Gonçalves, Yasmim G; Nunes, Débora C O; Napolitano, Danielle R; Maia, Pedro I S; Rodrigues, Renata S; Rodrigues, Veridiana M; Von Poelhsitz, Gustavo; Yoneyama, Kelly A G

    2017-10-01

    Leishmaniasis is a parasitic disease caused by protozoa of the genus Leishmania. The many complications presented by the current treatment - including high toxicity, high cost and parasite resistance - make the development of new therapeutic agents indispensable. The present study aims to evaluate the anti-Leishmania potential of new ruthenium(II) complexes, cis‑[Ru II (η 2 -O 2 CR)(dppm) 2 ]PF 6 , with dppm=bis(diphenylphosphino)methane and R=4-butylbenzoate (bbato) 1, 4-(methylthio)benzoate (mtbato) 2 and 3-hydroxy-4-methoxybenzoate (hmxbato) 3, in promastigote cytotoxicity and their effect on parasite-host interaction. The cytotoxicity of complexes was analyzed by MTT assay against Leishmania (Leishmania) amazonensis, Leishmania (Viannia) braziliensis, Leishmania (Leishmania) infantum promastigotes and the murine macrophage (RAW 264.7). The effect of complexes on parasite-host interaction was evaluated by in vitro infectivity assay performed in the presence of two different concentrations of each complex: the promastigote IC 50 value and the concentration nontoxic to 90% of RAW 264.7 macrophages. Complexes 1-3 exhibited potent cytotoxic activity against all Leishmania species assayed. The IC 50 values ranged from 7.52-12.59μM (complex 1); 0.70-3.28μM (complex 2) and 0.52-1.75μM (complex 3). All complexes significantly inhibited the infectivity index at both tested concentrations. The infectivity inhibitions ranged from 37 to 85%. Interestingly, the infectivity inhibitions due to complex action did not differ significantly at either of the tested concentrations, except for the complex 1 against Leishmania (Leishmania) infantum. The infectivity inhibitions resulted from reductions in both percentage of infected macrophages and number of parasites per macrophage. Taken together the results suggest remarkable leishmanicidal activity in vitro by these new ruthenium(II) complexes. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Adaptations in the energy metabolism of parasites

    NARCIS (Netherlands)

    van Grinsven, K.W.A.|info:eu-repo/dai/nl/304833436

    2009-01-01

    For this thesis fundamental research was performed on the metabolic adaptations found in parasites. Studying the adaptations in parasite metabolisms leads to a better understanding of parasite bioenergetics and can also result in the identification of new anti-parasitic drug targets. We focussed on

  4. Chronic Giardia muris infection in anti-IgM-treated mice. I. Analysis of immunoglobulin and parasite-specific antibody in normal and immunoglobulin-deficient animals.

    Science.gov (United States)

    Snider, D P; Gordon, J; McDermott, M R; Underdown, B J

    1985-06-01

    To investigate the role of B cells and antibody in the immune response of mice to the murine intestinal parasite Giardia muris, we used mice treated from birth with rabbit anti-IgM antisera (aIgM). Such mice developed in serum and in gut secretions extreme Ig deficiency (IgM, IgA, and IgG) relative to control animals. The aIgM-treated mice showed no anti-G. muris antibody in serum or in gut wash material. Infections of G. muris in these mice were chronic, with a high load of parasite present in the small bowel, as reflected by prolonged cyst excretion (greater than 11 wk) and high trophozoite counts. In contrast, normal, untreated mice or NRS-treated animals developed anti-parasite IgA and IgG antibody in serum, demonstrated IgA antibody against the parasite in gut washings, and expelled the parasite within 9 wk. These effects of aIgM treatment on the murine response to primary infection with G. muris were demonstrated in two strains of mice: BALB/c and (C57BL/6 X C3H/He) F1. It was also observed that the response to G. muris infection in untreated animals was characterized by higher than normal total secretion of IgA into the gut and a concomitant increase in the serum polymeric IgA level. Mice treated with aIgM had a marked decrease of both monomeric and polymeric IgA in serum, and little detectable IgA in the intestinal lumen. These experiments provide the first demonstration that anti-IgM treatment suppresses a specific intestinal antibody response to antigen, and provide evidence that B cells and antibody play a role in the development of an effective response to a primary infection with G. muris in mice.

  5. Application of small RNA technology for improved control of parasitic helminths.

    Science.gov (United States)

    Britton, Collette; Winter, Alan D; Marks, Neil D; Gu, Henry; McNeilly, Tom N; Gillan, Victoria; Devaney, Eileen

    2015-08-15

    Over the last decade microRNAs (miRNAs) and small interfering RNAs (siRNAs) have emerged as important regulators of post-transcriptional gene expression. miRNAs are short, non-coding RNAs that regulate a variety of processes including cancer, organ development and immune function. This class of small RNAs bind with partial complementarity to their target mRNA sequences, most often in the 3'UTR, to negatively regulate gene expression. In parasitic helminths, miRNAs are being increasingly studied for their potential roles in development and host-parasite interactions. The availability of genome data, combined with small RNA sequencing, has paved the way to profile miRNAs expressed at particular developmental stages for many parasitic helminths. While some miRNAs are conserved across species, others appear to be unique to specific parasites, suggesting important roles in adaptation and survival in the host environment. Some miRNAs are released from parasites, in exosomes or in protein complexes, and the potential effects of these on host immune function are being increasingly studied. In addition, release of miRNAs from schistosome and filarial parasites into host plasma can be exploited for the development of specific and sensitive diagnostic biomarkers of infection. Interfering with miRNA function, as well as silencing key components of the pathways they regulate, will progress our understanding of parasite development and provide a novel approach to therapeutic control. RNA interference (RNAi) by siRNAs has proven to be inconsistent in parasitic nematodes. However, the recent successes reported for schistosome and liver fluke RNAi, encourage further efforts to enhance delivery of RNA and improve in vitro culture systems and assays to monitor phenotypic effects in nematodes. These improvements are important for the establishment of reliable functional genomic platforms for novel drug and vaccine development. In this review we focus on the important roles of mi

  6. Parasitic helminths: a pharmacopeia of anti-inflammatory molecules.

    Science.gov (United States)

    Johnston, M J G; MacDonald, J A; McKay, D M

    2009-02-01

    Infection with parasitic helminths takes a heavy toll on the health and well-being of humans and their domestic livestock, concomitantly resulting in major economic losses. Analyses have consistently revealed bioactive molecules in extracts of helminths or in their excretory/secretory products that modulate the immune response of the host. It is our view that parasitic helminths are an untapped source of immunomodulatory substances that, in pure form, could become new drugs (or models for drug design) to treat disease. Here, we illustrate the range of immunomodulatory molecules in selected parasitic trematodes, cestodes and nematodes, their impact on the immune cells in the host and how the host may recognize these molecules. There are many examples of the partial characterization of helminth-derived immunomodulatory molecules, but these have not yet translated into new drugs, reflecting the difficulty of isolating and fully characterizing proteins, glycoproteins and lipid-based molecules from small amounts of parasite material. However, this should not deter the investigator, since analytical techniques are now being used to accrue considerable structural information on parasite-derived molecules, even when only minute quantities of tissue are available. With the introduction of methodologies to purify and structurally-characterize molecules from small amounts of tissue and the application of high throughput immunological assays, one would predict that an assessment of parasitic helminths will yield a variety of novel drug candidates in the coming years.

  7. The development of anti-heat stress clothing for construction workers in hot and humid weather.

    Science.gov (United States)

    Chan, Albert P C; Guo, Y P; Wong, Francis K W; Li, Y; Sun, S; Han, X

    2016-04-01

    The purpose of this study was to develop anti-heat stress clothing for construction workers in hot and humid weather. Following DeJonge's functional clothing design process, the design situation was explored, including clothing fabric heat/moisture transporting properties and UV protection and the aspects of clothing ergonomic design (mobility, convenience, and safety). The problem structure was derived from the results of the surveys in three local construction sites, which agreed well with the task requirements and observations. Specifications were consequently described and 30 commercially available fabrics were identified and tested. Fabric testing data and design considerations were inputted in S-smart system to predict the thermal functional performance of the clothing. A new uniform prototype was developed and evaluated. The results of all measurements suggest that the new uniform which incorporated fabrics with superior heat/moisture transporting properties and loose-fitting design could reduce the workers' heat stress and improve their comfort and work performance. Practitioner Summary: The construction workers' uniform currently used in Hong Kong during summer was unsatisfactory. Following DeJonge's functional clothing design process, an anti-heat stress uniform was developed by testing 30 fabrics and predicting clothing thermal functional performance using S-smart system. The new uniform could reduce the workers' heat stress and improve their comfort and work performance.

  8. Nuclear techniques in the study of parasitic infections

    International Nuclear Information System (INIS)

    1982-01-01

    Out of 57 papers published, 47 fall within the INIS subject scope. Seven main topics were covered: resistance to infections with protozoan parasites; resistance to infections with African trypanosomes and helminths of ruminant animals; resistance to infections with filarial parasites and schistosomes; pathology of parasitic infections; epidemiology and diagnosis of parasitic infections; physiology and biochemistry of parasitic organisms; pharmacodynamics of anti-parasitic agents

  9. Genetic variation in anti-parasite behavior in oysters

    Science.gov (United States)

    Behavioral avoidance of disease-causing parasites provides a first line of defense against the threat of infection, particularly when hosts are exposed to free-living parasite stages in the external environment. We report that suspension-feeding oysters (Crassostrea virginica) respond to the presenc...

  10. Adipose Tissue-Derived Mesenchymal Stromal Cells Protect Mice Infected with Trypanosoma cruzi from Cardiac Damage through Modulation of Anti-parasite Immunity.

    Science.gov (United States)

    Mello, Debora B; Ramos, Isalira P; Mesquita, Fernanda C P; Brasil, Guilherme V; Rocha, Nazareth N; Takiya, Christina M; Lima, Ana Paula C A; Campos de Carvalho, Antonio C; Goldenberg, Regina S; Carvalho, Adriana B

    2015-01-01

    Chagas disease, caused by the protozoan Trypanosoma cruzi (T. cruzi), is a complex disease endemic in Central and South America. It has been gathering interest due to increases in non-vectorial forms of transmission, especially in developed countries. The objective of this work was to investigate if adipose tissue-derived mesenchymal stromal cells (ASC) can alter the course of the disease and attenuate pathology in a mouse model of chagasic cardiomyopathy. ASC were injected intraperitoneally at 3 days post-infection (dpi). Tracking by bioluminescence showed that cells remained in the abdominal cavity for up to 9 days after injection and most of them migrated to the abdominal or subcutaneous fat, an early parasite reservoir. ASC injection resulted in a significant reduction in blood parasitemia, which was followed by a decrease in cardiac tissue inflammation, parasitism and fibrosis at 30 dpi. At the same time point, analyses of cytokine release in cells isolated from the heart and exposed to T. cruzi antigens indicated an anti-inflammatory response in ASC-treated animals. In parallel, splenocytes exposed to the same antigens produced a pro-inflammatory response, which is important for the control of parasite replication, in placebo and ASC-treated groups. However, splenocytes from the ASC group released higher levels of IL-10. At 60 dpi, magnetic resonance imaging revealed that right ventricular (RV) dilation was prevented in ASC-treated mice. In conclusion, the injection of ASC early after T. cruzi infection prevents RV remodeling through the modulation of immune responses. Lymphoid organ response to the parasite promoted the control of parasite burden, while the heart, a target organ of Chagas disease, was protected from damage due to an improved control of inflammation in ASC-treated mice.

  11. Adipose Tissue-Derived Mesenchymal Stromal Cells Protect Mice Infected with Trypanosoma cruzi from Cardiac Damage through Modulation of Anti-parasite Immunity.

    Directory of Open Access Journals (Sweden)

    Debora B Mello

    Full Text Available Chagas disease, caused by the protozoan Trypanosoma cruzi (T. cruzi, is a complex disease endemic in Central and South America. It has been gathering interest due to increases in non-vectorial forms of transmission, especially in developed countries. The objective of this work was to investigate if adipose tissue-derived mesenchymal stromal cells (ASC can alter the course of the disease and attenuate pathology in a mouse model of chagasic cardiomyopathy.ASC were injected intraperitoneally at 3 days post-infection (dpi. Tracking by bioluminescence showed that cells remained in the abdominal cavity for up to 9 days after injection and most of them migrated to the abdominal or subcutaneous fat, an early parasite reservoir. ASC injection resulted in a significant reduction in blood parasitemia, which was followed by a decrease in cardiac tissue inflammation, parasitism and fibrosis at 30 dpi. At the same time point, analyses of cytokine release in cells isolated from the heart and exposed to T. cruzi antigens indicated an anti-inflammatory response in ASC-treated animals. In parallel, splenocytes exposed to the same antigens produced a pro-inflammatory response, which is important for the control of parasite replication, in placebo and ASC-treated groups. However, splenocytes from the ASC group released higher levels of IL-10. At 60 dpi, magnetic resonance imaging revealed that right ventricular (RV dilation was prevented in ASC-treated mice.In conclusion, the injection of ASC early after T. cruzi infection prevents RV remodeling through the modulation of immune responses. Lymphoid organ response to the parasite promoted the control of parasite burden, while the heart, a target organ of Chagas disease, was protected from damage due to an improved control of inflammation in ASC-treated mice.

  12. Research on construction quality and improvement of assembly construction

    Science.gov (United States)

    Cheng, Fei

    2017-11-01

    Based on the acceleration of the urbanization process and the improvement of the quality of life of our residents, the demand for building construction has been increasing. In this context, the construction industry in order to promote the construction efficiency, quality improvement, to meet the needs of the development of the times to strengthen the new technology, the use of new technologies. At present, China’s engineering construction units in the process of carrying out the project to strengthen the use of assembly-type construction technology, which thus achieved for the traditional construction work low-level, high time-consuming issues, and promote the steady improvement of production efficiency. Based on this, this paper focuses on the analysis of the connotation of the assembly structure and analyzes the quality problems in the construction process of the construction projects and puts forward the improvement measures to promote the improvement of the building quality and the construction of the building Construction speed. Based on this, this paper analyzes the structural system and design of prefabricated building.

  13. On the importance of targeting parasite stem cells in anti-echinococcosis drug development

    Directory of Open Access Journals (Sweden)

    Brehm Klaus

    2014-01-01

    Full Text Available The life-threatening diseases alveolar and cystic echinococcoses are caused by larvae of the tapeworms Echinococcus multilocularis and E. granulosus, respectively. In both cases, intermediate hosts, such as humans, are infected by oral uptake of oncosphere larvae, followed by asexual multiplication and almost unrestricted growth of the metacestode within host organs. Besides surgery, echinococcosis treatment relies on benzimidazole-based chemotherapy, directed against parasite beta-tubulin. However, since beta-tubulins are highly similar between cestodes and humans, benzimidazoles can only be applied at parasitostatic doses and are associated with adverse side effects. Mostly aiming at identifying alternative drug targets, the nuclear genome sequences of E. multilocularis and E. granulosus have recently been characterized, revealing a large number of druggable targets that are expressed by the metacestode. Furthermore, recent cell biological investigations have demonstrated that E. multilocularis employs pluripotent stem cells, called germinative cells, which are the only parasite cells capable of proliferation and which give rise to all differentiated cells. Hence, the germinative cells are the crucial cell type mediating proliferation of E. multilocularis, and most likely also E. granulosus, within host organs and should also be responsible for parasite recurrence upon discontinuation of chemotherapy. Interestingly, recent investigations have also indicated that germinative cells might be less sensitive to chemotherapy because they express a beta-tubulin isoform with limited affinity to benzimidazoles. In this article, we briefly review the recent findings concerning Echinococcus genomics and stem cell research and propose that future research into anti-echinococcosis drugs should also focus on the parasite’s stem cell population.

  14. Anti-Parasitic Activities of Allium sativum and Allium cepa against Trypanosoma b. brucei and Leishmania tarentolae.

    Science.gov (United States)

    Krstin, Sonja; Sobeh, Mansour; Braun, Markus Santhosh; Wink, Michael

    2018-04-21

    Background: Garlics and onions have been used for the treatment of diseases caused by parasites and microbes since ancient times. Trypanosomiasis and leishmaniasis are a concern in many areas of the world, especially in poor countries. Methods: Trypanosoma brucei brucei and Leishmania tarentolae were used to investigate the anti-parasitic effects of dichloromethane extracts of Allium sativum (garlic) and Allium cepa (onion) bulbs. As a confirmation of known antimicrobial activities, they were studied against a selection of G-negative, G-positive bacteria and two fungi. Chemical analyses were performed using high-performance liquid chromatography (HPLC) and electrospray ionization-mass spectrometry (LC-ESI-MS/MS). Results: Chemical analyses confirmed the abundance of several sulfur secondary metabolites in garlic and one (zwiebelane) in the onion extract. Both extracts killed both types of parasites efficiently and inhibited the Trypanosoma brucei trypanothione reductase irreversibly. In addition, garlic extract decreased the mitochondrial membrane potential in trypanosomes. Garlic killed the fungi C. albicans and C. parapsilosis more effectively than the positive control. The combinations of garlic and onion with common trypanocidal and leishmanicidal drugs resulted in a synergistic or additive effect in 50% of cases. Conclusion: The mechanism for biological activity of garlic and onion appears to be related to the amount and the profile of sulfur-containing compounds. It is most likely that vital substances inside the parasitic cell, like trypanothione reductase, are inhibited through disulfide bond formation between SH groups of vital redox compounds and sulfur-containing secondary metabolites.

  15. Microaspiration of esophageal gland cells and cDNA library construction for identifying parasitism genes of plant-parasitic nematodes.

    Science.gov (United States)

    Hussey, Richard S; Huang, Guozhong; Allen, Rex

    2011-01-01

    Identifying parasitism genes encoding proteins secreted from a plant-parasitic nematode's esophageal gland cells and injected through its stylet into plant tissue is the key to understanding the molecular basis of nematode parasitism of plants. Parasitism genes have been cloned by directly microaspirating the cytoplasm from the esophageal gland cells of different parasitic stages of cyst or root-knot nematodes to provide mRNA to create a gland cell-specific cDNA library by long-distance reverse-transcriptase polymerase chain reaction. cDNA clones are sequenced and deduced protein sequences with a signal peptide for secretion are identified for high-throughput in situ hybridization to confirm gland-specific expression.

  16. [Research progress on cathepsin F of parasitic helminths].

    Science.gov (United States)

    Qu, Zi-Gang; Fu, Bao-Quan

    2013-10-01

    Cathepsin F is an important member of papain-like subfamily in cysteine protease family. Cathepsin F of helminth parasites can hydrolyze the specific substrate, degrade host protein such as hemoglobin for nutrition, and be involved in invasion into host tissue. Therefore, cathepsin F serves as a potential target for parasitic disease immunodiagnosis, vaccine design and anti-parasite drug screening. This article reviews the structural characteristics and mechanisms of cathepsin F, and research advances on cathepsin F of parasitic helminths.

  17. Plasmodium falciparum in vitro continuous culture conditions: A comparison of parasite susceptibility and tolerance to anti-malarial drugs throughout the asexual intra-erythrocytic life cycle.

    Science.gov (United States)

    Duffy, Sandra; Avery, Vicky M

    2017-12-01

    The continuous culture of Plasmodium falciparum is often seen as a means to an end, that end being to probe the biology of the parasite in question, and ultimately for many in the malaria drug discovery arena, to identify means of killing the parasite in order to treat malaria. In vitro continuous culture of Plasmodium falciparum is a fundamental requirement when undertaking malaria research where the primary objectives utilise viable parasites of a desired lifecycle stage. This investigation, and resulting data, compared the impact culturing Plasmodium falciparum long term (4 months) in different environmental conditions had on experimental outcomes and thus conclusions. The example presented here focused specifically on the effect culture conditions had on the in vitro tolerance of Plasmodium falciparum to standard anti-malarial drugs, including artemisinin and lumefantrine. Historical data from an independent experiment for 3D7-ALB (5% O 2 ) was also compared with that obtained from this study. We concluded that parasites cultured for several months in media supplemented with a serum substitute such as Albumax II ® or within hyperoxic conditions (21% O 2 ), demonstrate highly variable responses to artemisinin and lumefantrine but not all anti-malarial drugs, when compared to those cultured in human serum in combination with Albumax II ® under normoxic conditions (5% O 2 ) for the parasite. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  18. Assessing the usefulness of mineral licks containing herbal extracts with anti-parasitic properties for the control of gastrointestinal helminths in grazing sheep – a field trial

    Directory of Open Access Journals (Sweden)

    Nosal P.

    2016-06-01

    Full Text Available One of the alternative methods of parasite control, of particular importance in sustainable farming, is the use of medicinal plants. The specific aim of the present field trial was to assess the anti-parasitic effects of herbal extracts contained in a commercially available lick formulation for sheep. At the outset of this study conducted during the grazing season, all animals were de-wormed and then randomly assigned to one of the two separately kept groups (treatment and control, each consisting of 25 animals (11 ewes and 14 lambs. The treatment group received mineral licks containing the extracts of the plants with anti-parasitic properties, while control animals received standard mineral licks ad libitum. Rectal fecal samples were collected monthly from all animals for the McMaster analyses. There were no significant differences in the prevalence and intensity of helminth infections between the treatment and control groups. Thus, we were not able to ascertain the efficacy of the commercial herbal de-wormer tested for the control of gastrointestinal helminths in grazing ewes and their lambs.

  19. Scaffold proteins LACK and TRACK as potential drug targets in kinetoplastid parasites: Development of inhibitors

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    Nir Qvit

    2016-04-01

    Full Text Available Parasitic diseases cause ∼500,000 deaths annually and remain a major challenge for therapeutic development. Using a rational design based approach, we developed peptide inhibitors with anti-parasitic activity that were derived from the sequences of parasite scaffold proteins LACK (Leishmania's receptor for activated C-kinase and TRACK (Trypanosoma receptor for activated C-kinase. We hypothesized that sequences in LACK and TRACK that are conserved in the parasites, but not in the mammalian ortholog, RACK (Receptor for activated C-kinase, may be interaction sites for signaling proteins that are critical for the parasites' viability. One of these peptides exhibited leishmanicidal and trypanocidal activity in culture. Moreover, in infected mice, this peptide was also effective in reducing parasitemia and increasing survival without toxic effects. The identified peptide is a promising new anti-parasitic drug lead, as its unique features may limit toxicity and drug-resistance, thus overcoming central limitations of most anti-parasitic drugs. Keywords: Chagas disease, Leishmaniasis, Peptide, LACK, TRACK, Scaffold protein

  20. Manipulating small ruminant parasite epidemiology through the combination of nutritional strategies.

    Science.gov (United States)

    Houdijk, Jos G M; Kyriazakis, Ilias; Kidane, Alemayehu; Athanasiadou, Spiridoula

    2012-05-04

    It is increasingly being recognized that non-chemical parasite control strategies may need to be combined to control more effectively gastrointestinal parasitism, result in resilient production systems and reduce reliance on anthelmintics. Here, we consider if and how metabolizable protein (MP) supplementation and anti-parasitic plant secondary metabolites (PSM) may modulate parasite epidemiology through intervention in pasture contamination, development of infection on pasture and larval challenge as target processes. We then propose that combining two or more non-chemical parasite control strategies may have additive effects on host resistance, especially if the individual strategies target different drivers of parasite epidemiology, different processes in the parasite life cycle or different phases of acquired immunity to parasites. This epidemiological framework is used to review recent findings on combining maternal MP supplementation and grazing the PSM-rich bioactive forage chicory as an example of combining nutritional treatments to manipulate parasite epidemiology in a temperate production system. In the absence of available data for combined nutritional strategies in tropical production systems, we make predictions on the consequences of combining such strategies in these systems. We conclude that currently published studies on combining nutritional strategies under temperate conditions show potential to improve additively host resilience and reduce reliance on anthelmintics; however, effects on epidemiology have to date not shown the additive results hypothesized. The framework developed may assist further in evaluating combined (nutritional) strategies to manipulate parasite epidemiology. Copyright © 2011 Elsevier B.V. All rights reserved.

  1. Systems analysis of chaperone networks in the malarial parasite Plasmodium falciparum.

    Directory of Open Access Journals (Sweden)

    Soundara Raghavan Pavithra

    2007-09-01

    Full Text Available Molecular chaperones participate in the maintenance of cellular protein homeostasis, cell growth and differentiation, signal transduction, and development. Although a vast body of information is available regarding individual chaperones, few studies have attempted a systems level analysis of chaperone function. In this paper, we have constructed a chaperone interaction network for the malarial parasite, Plasmodium falciparum. P. falciparum is responsible for several million deaths every year, and understanding the biology of the parasite is a top priority. The parasite regularly experiences heat shock as part of its life cycle, and chaperones have often been implicated in parasite survival and growth. To better understand the participation of chaperones in cellular processes, we created a parasite chaperone network by combining experimental interactome data with in silico analysis. We used interolog mapping to predict protein-protein interactions for parasite chaperones based on the interactions of corresponding human chaperones. This data was then combined with information derived from existing high-throughput yeast two-hybrid assays. Analysis of the network reveals the broad range of functions regulated by chaperones. The network predicts involvement of chaperones in chromatin remodeling, protein trafficking, and cytoadherence. Importantly, it allows us to make predictions regarding the functions of hypothetical proteins based on their interactions. It allows us to make specific predictions about Hsp70-Hsp40 interactions in the parasite and assign functions to members of the Hsp90 and Hsp100 families. Analysis of the network provides a rational basis for the anti-malarial activity of geldanamycin, a well-known Hsp90 inhibitor. Finally, analysis of the network provides a theoretical basis for further experiments designed toward understanding the involvement of this important class of molecules in parasite biology.

  2. Construct ability Improvement for Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dae Soo; Lee, Jong Rim; Kim, Jong Ku [Korea Electric Power Research Institute, Taejon (Korea, Republic of)

    1997-12-31

    The purpose of this study was to identify methods for improving the construct ability of nuclear power plants. This study reviewed several references of current construction practices of domestic and overseas nuclear plants in order to identify potential methods for improving construct ability. The identified methods for improving construct ability were then evaluated based on the applicability to domestic nuclear plant construction. The selected methods are expected to reduce the construction period, improve the quality of construction, cost, safety, and productivity. Selection of which methods should be implemented will require further evaluation of construction modifications, design changes, contract revisions. Among construction methods studied, platform construction methods can be applied through construction sequence modification without significant design changes, and Over the Top construction method of the NSSS, automatic welding of RCL pipes, CLP modularization, etc., are considered to be applied after design modification and adjustment of material lead time. (author). 49 refs., figs., tabs.

  3. Anti-Markovnikov hydroimination of terminal alkynes in gold-catalyzed pyridine construction from ammonia.

    Science.gov (United States)

    Wang, Liliang; Kong, Lingbing; Li, Yongxin; Ganguly, Rakesh; Kinjo, Rei

    2015-08-11

    Gold-catalyzed hydroimination of terminal alkynes, giving rise to anti-Markovnikov adducts concomitant with unstable Markovnikov adducts is described. The elementary step can be applied for the construction of pyridine derivatives from ammonia and alkynes.

  4. Intestinal parasitism and socio-environmental factors among Mbyá-Guarani indians, Porto Alegre, Rio Grande do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Clara Lia Costa Brandelli

    2012-06-01

    Full Text Available Disturbing data reveal the prevalence of intestinal parasites and their relationship with socio-environmental factors among Mbyá-Guarani Indians. The prevalence was determined by spontaneous sedimentation in water, centrifugation-floatation, and Kato-Katz. A socioeconomic questionnaire was submitted to each family. The overall prevalence of intestinal parasites was 88.7%, and 45.5% were polyparasitized. There was 90.5% prevalence of enteric parasites in children (1-12- year-old, and 85% among 13-65-year-old individuals, indicating that both age groups are extensively parasitized. The parasite load was low to moderate for geohelminths and 75% of the families did not have latrine, thus the practice of defecation occurred outdoors. These findings suggest that the multiple intestinal parasitism in the Mbyá-Guarani community is high to the point of being the rule, and that it relates essentially to the traditional lifestyle and health habits. It is urgently necessary to implement the association of anti-parasitic treatment with sanitation improvement. This should be done simultaneously with health education activities for this population.

  5. Intestinal parasitism and socio-environmental factors among Mbyá-Guarani Indians, Porto Alegre, Rio Grande do Sul, Brazil.

    Science.gov (United States)

    Brandelli, Clara Lia Costa; de Carli, Geraldo Attilio; Macedo, Alexandre José; Tasca, Tiana

    2012-01-01

    Disturbing data reveal the prevalence of intestinal parasites and their relationship with socio-environmental factors among Mbyá-Guarani Indians. The prevalence was determined by spontaneous sedimentation in water, centrifugation-floatation, and Kato-Katz. A socioeconomic questionnaire was submitted to each family. The overall prevalence of intestinal parasites was 88.7%, and 45.5% were polyparasitized. There was 90.5% prevalence of enteric parasites in children (1-12- year-old), and 85% among 13-65-year-old individuals, indicating that both age groups are extensively parasitized. The parasite load was low to moderate for geohelminths and 75% of the families did not have latrine, thus the practice of defecation occurred outdoors. These findings suggest that the multiple intestinal parasitism in the Mbyá-Guarani community is high to the point of being the rule, and that it relates essentially to the traditional lifestyle and health habits. It is urgently necessary to implement the association of anti-parasitic treatment with sanitation improvement. This should be done simultaneously with health education activities for this population.

  6. Immune escape strategies of malaria parasites

    Directory of Open Access Journals (Sweden)

    Pollyanna Stephanie Gomes

    2016-10-01

    Full Text Available Malaria is one of the most life-threatening infectious diseases worldwide. Immunity to malaria is slow and short-lived despite the repeated parasite exposure in endemic areas. Malaria parasites have evolved refined machinery to evade the immune system based on a range of genetic changes that include allelic variation, biomolecular exposure of proteins and intracellular replication. All of these features increase the probability of survival in both mosquitoes and the vertebrate host. Plasmodium species escape from the first immunological trap in its invertebrate vector host, the Anopheles mosquitoes. The parasites have to pass through various immunological barriers within the mosquito such as anti-microbial molecules and the mosquito microbiota in order to achieve successful transmission to the vertebrate host. Within these hosts, Plasmodium species employ various immune evasion strategies during different life cycle stages. Parasite persistence against the vertebrate immune response depends on the balance among virulence factors, pathology, metabolic cost of the host immune response, and the parasites ability to evade the immune response. In this review we discuss the strategies that Plasmodium parasites use to avoid the vertebrate host immune system and how they promote successful infection and transmission.

  7. ANTI-MICROBIAL AND ANTI-AMOEBIC ACTIVITY SOME AZOMETHINES - POTENTIAL TEXTILE DYESTUFFS

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    DJORDJEVIC Dragan

    2016-05-01

    Full Text Available In this paper, new synthesized three azomethine derivatives applied in dyeing textiles checking the anti-microbial properties of active components, at the same time [1-3]. The emphasis is thrown on the verification of anti-microbial properties that are important for obtaining textile with significantly improved performance. All compounds were characterized and evaluated for their anti-microbial activity against 7 pathogenic bacteria, 1 parasitic protozoan and 1 fungus. It estimated anti-bacterial activity in vitro against the following microorganisms Staphylococcus aureus, Bacillus anthracis, Streptococcus faecalis, Enterobacter sp., Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis, and Candida albicans. The anti-amoebic activity in vitro was evaluated against the HM1: IMSS strain of Entamoeba histolytica and the results were compared with the standard drug, metronidazole. The synthesized azomethines, showed very good substantivity for wool fibers, gave fine coloring, with good degree of exhaustion after dyeing. The combination of extended synthetic analogues of natural molecules leads to discovery of chemical entities which might be excellent anti-microbial and anti-amoebic compounds as depicted in our results. Being highly the effects this compound can be explored in future as an option for decreasing pathogenic potential of infecting from different sources. Azomethines containing hydrazone (dyestuff 1 and phenylhydrazone (dyestuff 2 as moiety show average yield and moderate inhibition activity while azomethines containing thiosemicarbazone (dyestuff 3 as moiety show higher yield and greater inhibition activity towards gram-negative and gram-positive bacteria as well as a fungus.

  8. Ultrasonic Nanobubbles Carrying Anti-PSMA Nanobody: Construction and Application in Prostate Cancer-Targeted Imaging.

    Directory of Open Access Journals (Sweden)

    Xiaozhou Fan

    Full Text Available To facilitate prostate cancer imaging using targeted molecules, we constructed ultrasonic nanobubbles coupled with specific anti-PSMA (prostate specific membrane antigen nanobodies, and evaluated their in vitro binding capacity and in vivo imaging efficacy. The "targeted" nanobubbles, which were constructed via a biotin-streptavidin system, had an average diameter of 487.60 ± 33.55 nm and carried the anti-PSMA nanobody as demonstrated by immunofluorescence. Microscopy revealed targeted binding of nanobubbles in vitro to PSMA-positive cells. Additionally, ultrasonography indicators of nanobubble imaging (including arrival time, peak time, peak intensity and enhanced duration were evaluated for the ultrasound imaging in three kinds of animal xenografts (LNCaP, C4-2 and MKN45, and showed that these four indicators of targeted nanobubbles exhibited significant differences from blank nanobubbles. Therefore, this study not only presents a novel approach to target prostate cancer ultrasonography, but also provides the basis and methods for constructing small-sized and high-efficient targeted ultrasound nanobubbles.

  9. Parasitic Helminths: New Weapons against Immunological Disorders

    OpenAIRE

    Osada, Yoshio; Kanazawa, Tamotsu

    2010-01-01

    The prevalence of allergic and autoimmune diseases is increasing in developed countries, possibly due to reduced exposure to microorganisms in childhood (hygiene hypothesis). Epidemiological and experimental evidence in support of this hypothesis is accumulating. In this context, parasitic helminths are now important candidates for antiallergic/anti-inflammatory agents. Here we summarize antiallergic/anti-inflammatory effects of helminths together along with our own study of the effects of Sc...

  10. Polypyridylruthenium(II complexes exert anti-schistosome activity and inhibit parasite acetylcholinesterases.

    Directory of Open Access Journals (Sweden)

    Madhu K Sundaraneedi

    2017-12-01

    Full Text Available Schistosomiasis affects over 200 million people and there are concerns whether the current chemotherapeutic control strategy (periodic mass drug administration with praziquantel (PZQ-the only licenced anti-schistosome compound is sustainable, necessitating the development of new drugs.We investigated the anti-schistosome efficacy of polypyridylruthenium(II complexes and showed they were active against all intra-mammalian stages of S. mansoni. Two compounds, Rubb12-tri and Rubb7-tnl, which were among the most potent in their ability to kill schistosomula and adult worms and inhibit egg hatching in vitro, were assessed for their efficacy in a mouse model of schistosomiasis using 5 consecutive daily i.v. doses of 2 mg/kg (Rubb12-tri and 10 mg/kg (Rubb7-tnl. Mice treated with Rubb12-tri showed an average 42% reduction (P = 0.009, over two independent trials, in adult worm burden. Liver egg burdens were not significantly decreased in either drug-treated group but ova from both of these groups showed significant decreases in hatching ability (Rubb12-tri-68%, Rubb7-tnl-56% and were significantly morphologically altered (Rubb12-tri-62% abnormal, Rubb7-tnl-35% abnormal. We hypothesize that the drugs exerted their activity, at least partially, through inhibition of both neuronal and tegumental acetylcholinesterases (AChEs, as worms treated in vitro showed significant decreases in activity of these enzymes. Further, treated parasites exhibited a significantly decreased ability to uptake glucose, significantly depleted glycogen stores and withered tubercules (a site of glycogen storage, implying drug-mediated interference in this nutrient acquisition pathway.Our data provide compelling evidence that ruthenium complexes are effective against all intra-mammalian stages of schistosomes, including schistosomula (refractory to PZQ and eggs (agents of disease transmissibility. Further, the results of this study suggest that schistosome AChE is a target of

  11. Identification of a secreted casein kinase 1 in Leishmania donovani: effect of protein over expression on parasite growth and virulence.

    Directory of Open Access Journals (Sweden)

    Mary Dan-Goor

    Full Text Available Casein kinase 1 (CK1 plays an important role in eukaryotic signaling pathways, and their substrates include key regulatory proteins involved in cell differentiation, proliferation and chromosome segregation. The Leishmania genome encodes six potential CK1 isoforms, of which five have orthologs in other trypanosomatidae. Leishmania donovani CK1 isoform 4 (Ldck1.4, orthologous to LmjF27.1780 is unique to Leishmania and contains a putative secretion signal peptide. The full-length gene and three shorter constructs were cloned and expressed in E. coli as His-tag proteins. Only the full-length 62.3 kDa protein showed protein kinase activity indicating that the N-terminal and C-terminal domains are essential for protein activity. LdCK1.4-FLAG was stably over expressed in L. donovani, and shown by immunofluorescence to be localized primarily in the cytosol. Western blotting using anti-FLAG and anti-CK1.4 antibodies showed that this CK1 isoform is expressed and secreted by promastigotes. Over expression of LdCK1.4 had a significant effect on promastigote growth in culture with these parasites growing to higher cell densities than the control parasites (wild-type or Ld:luciferase, P<0.001. Analysis by flow cytometry showed a higher percentage, ∼4-5-fold, of virulent metacyclic promastigotes on day 3 among the LdCK1.4 parasites. Finally, parasites over expressing LdCK1.4 gave significantly higher infections of mouse peritoneal macrophages compared to wild-type parasites, 28.6% versus 6.3%, respectively (p = 0.0005. These results suggest that LdCK1.4 plays an important role in parasite survival and virulence. Further studies are needed to validate CK1.4 as a therapeutic target in Leishmania.

  12. Anti-malarial Drug Design by Targeting Apicoplasts: New Perspectives

    Directory of Open Access Journals (Sweden)

    Avinaba Mukherjee

    2016-03-01

    Full Text Available Objectives: Malaria has been a major global health problem in recent times with increasing mortality. Current treatment methods include parasiticidal drugs and vaccinations. However, resistance among malarial parasites to the existing drugs has emerged as a significant area of concern in anti-malarial drug design. Researchers are now desperately looking for new targets to develop anti-malarials drug which is more target specific. Malarial parasites harbor a plastid-like organelle known as the ‘apicoplast’, which is thought to provide an exciting new outlook for the development of drugs to be used against the parasite. This review elaborates on the current state of development of novel compounds targeted againstemerging malaria parasites. Methods: The apicoplast, originates by an endosymbiotic process, contains a range of metabolic pathways and housekeeping processes that differ from the host body and thereby presents ideal strategies for anti-malarial drug therapy. Drugs are designed by targeting the unique mechanism of the apicoplasts genetic machinery. Several anabolic and catabolic processes, like fatty acid, isopenetyl diphosphate and heme synthess in this organelle, have also been targeted by drugs. Results: Apicoplasts offer exciting opportunities for the development of malarial treatment specific drugs have been found to act by disrupting this organelle’s function, which wouldimpede the survival of the parasite. Conclusion: Recent advanced drugs, their modes of action, and their advantages in the treatment of malaria by using apicoplasts as a target are discussed in this review which thought to be very useful in desigining anti-malarial drugs. Targetting the genetic machinery of apicoplast shows a great advantange regarding anti-malarial drug design. Critical knowledge of these new drugs would give a healthier understanding for deciphering the mechanism of action of anti-malarial drugs when targeting apicoplasts to overcome drug

  13. Assessing the utility of an anti-malarial pharmacokinetic-pharmacodynamic model for aiding drug clinical development

    Directory of Open Access Journals (Sweden)

    Zaloumis Sophie

    2012-08-01

    Full Text Available Abstract Background Mechanistic within-host models relating blood anti-malarial drug concentrations with the parasite-time profile help in assessing dosing schedules and partner drugs for new anti-malarial treatments. A comprehensive simulation study to assess the utility of a stage-specific pharmacokinetic-pharmacodynamic (PK-PD model for predicting within-host parasite response was performed. Methods Three anti-malarial combination therapies were selected: artesunate-mefloquine, dihydroartemisinin-piperaquine, and artemether-lumefantrine. The PK-PD model included parameters to represent the concentration-time profiles of both drugs, the initial parasite burden and distribution across the parasite life cycle, and the parasite multiplication factor due to asexual reproduction. The model also included the maximal killing rate of each drug, and the blood drug concentration associated with half of that killing effect (in vivo EC50, derived from the in vitro IC50, the extent of binding to 0.5% Albumax present in the in vitro testing media, and the drugs plasma protein binding and whole blood to plasma partitioning ratio. All stochastic simulations were performed using a Latin-Hypercube-Sampling approach. Results The simulations demonstrated that the proportion of patients cured was highly sensitive to the in vivo EC50 and the maximal killing rate of the partner drug co-administered with the artemisinin derivative. The in vivo EC50 values that corresponded to on average 95% of patients cured were much higher than the adjusted values derived from the in vitro IC50. The proportion clinically cured was not strongly influenced by changes in the parameters defining the age distribution of the initial parasite burden (mean age of 4 to 16 hours and the parasite multiplication factor every life cycle (ranging from 8 to 12 fold/cycle. The median parasite clearance times, however, lengthened as the standard deviation of the initial parasite burden increased (i

  14. Anti-parasite treatment and blood biochemistry in raptor nestlings

    DEFF Research Database (Denmark)

    Hanssen, Sveinn Are; Sonne, Christian; Bustnes, Jan Ove

    2017-01-01

    We investigated the effects of parasite removal on various blood clinical–chemical variables (BCCVs). BCCVs are indicators of health, reflecting, e.g., homeostasis of liver, kidney function, and bone metabolism. The study was conducted in Norway on chicks of two predatory birds: White-tailed Eagl...

  15. Getting the most out of parasitic helminth transcriptomes using HelmDB: implications for biology and biotechnology.

    Science.gov (United States)

    Mangiola, Stefano; Young, Neil D; Korhonen, Pasi; Mondal, Alinda; Scheerlinck, Jean-Pierre; Sternberg, Paul W; Cantacessi, Cinzia; Hall, Ross S; Jex, Aaron R; Gasser, Robin B

    2013-12-01

    Compounded by a massive global food shortage, many parasitic diseases have a devastating, long-term impact on animal and human health and welfare worldwide. Parasitic helminths (worms) affect the health of billions of animals. Unlocking the systems biology of these neglected pathogens will underpin the design of new and improved interventions against them. Currently, the functional annotation of genomic and transcriptomic sequence data for socio-economically important parasitic worms relies almost exclusively on comparative bioinformatic analyses using model organism- and other databases. However, many genes and gene products of parasitic helminths (often >50%) cannot be annotated using this approach, because they are specific to parasites and/or do not have identifiable homologs in other organisms for which sequence data are available. This inability to fully annotate transcriptomes and predicted proteomes is a major challenge and constrains our understanding of the biology of parasites, interactions with their hosts and of parasitism and the pathogenesis of disease on a molecular level. In the present article, we compiled transcriptomic data sets of key, socioeconomically important parasitic helminths, and constructed and validated a curated database, called HelmDB (www.helmdb.org). We demonstrate how this database can be used effectively for the improvement of functional annotation by employing data integration and clustering. Importantly, HelmDB provides a practical and user-friendly toolkit for sequence browsing and comparative analyses among divergent helminth groups (including nematodes and trematodes), and should be readily adaptable and applicable to a wide range of other organisms. This web-based, integrative database should assist 'systems biology' studies of parasitic helminths, and the discovery and prioritization of novel drug and vaccine targets. This focus provides a pathway toward developing new and improved approaches for the treatment and control

  16. Structural Basis for Carbohydrate Recognition and Anti-inflammatory Modulation by Gastrointestinal Nematode Parasite Toxascaris leonina Galectin*

    Science.gov (United States)

    Hwang, Eun Young; Jeong, Mi Suk; Park, Sang Kyun; Ha, Sung Chul; Yu, Hak Sun; Jang, Se Bok

    2016-01-01

    Toxascaris leonina galectin (Tl-gal) is a galectin-9 homologue protein isolated from an adult worm of the canine gastrointestinal nematode parasite, and Tl-gal-vaccinated challenge can inhibit inflammation in inflammatory bowel disease-induced mice. We determined the first X-ray structures of full-length Tl-gal complexes with carbohydrates (lactose, N-acetyllactosamine, lacto-N-tetraose, sialyllactose, and glucose). Bonds were formed on concave surfaces of both carbohydrate recognition domains (CRDs) in Tl-gal. All binding sites were found in the HXXXR and WGXEER motifs. Charged Arg61/Arg196 and Glu80/Glu215 on the conserved motif of Tl-gal N-terminal CRD and C-terminal CRD are critical amino acids for recognizing carbohydrate binding, and the residues can affect protein folding and structure. The polar amino acids His, Asn, and Trp are also important residues for the interaction with carbohydrates through hydrogen bonding. Hemagglutination activities of Tl-gal were inhibited by interactions with carbohydrates and mutations. We found that the mutation of Tl-gal (E80A/E215A) at the carbohydrate binding region induced protein aggregation and could be caused in many diseases. The short linker region between the N-terminal and C-terminal CRDs of Tl-gal was very stable against proteolysis and maintained its biological activity. This structural information is expected to elucidate the carbohydrate recognition mechanism of Tl-gal and improve our understanding of anti-inflammatory mediators and modulators of immune response. PMID:27742836

  17. Parasites, Plants, and People.

    Science.gov (United States)

    Johnson, Marion; Moore, Tony

    2016-06-01

    Anthelminthic resistance is acknowledged worldwide and is a major problem in Aotearoa New Zealand, thus alternative parasite management strategies are imperative. One Health is an initiative linking animal, human, and environmental health. Parasites, plants, and people illustrate the possibilities of providing diverse diets for stock thereby lowering parasite burdens, improving the cultural wellbeing of a local community, and protecting the environment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Towards improving construction labor productivity and projects’ performance

    Directory of Open Access Journals (Sweden)

    Mostafa E. Shehata

    2011-12-01

    Full Text Available Proper management of resources in construction projects can yield substantial savings in time and cost. As construction is a labor-intensive industry, this paper focuses on labor productivity in the construction industry. This study considers the current state-of-the-art issues relevant to this subject. It covers the construction labor productivity definitions, aspects, measurements, factors affecting it, different techniques used for measuring it and modeling techniques. The main outcome from the literature is that there is no standard definition of productivity. This study provides a guide for necessary steps required to improve construction labor productivity and consequently, the project performance. It can help improve the overall performance of construction projects through the implementation of the concept of benchmarks. Also, it gives an up to date concept of loss of productivity measurement for construction productivity claims. Two major case studies, from the literature, are presented to show construction labor productivity rates, factors affecting construction labor productivity and how to improve it.

  19. Stable-isotope analysis: a neglected tool for placing parasites in food webs.

    Science.gov (United States)

    Sabadel, A J M; Stumbo, A D; MacLeod, C D

    2018-02-28

    Parasites are often overlooked in the construction of food webs, despite their ubiquitous presence in almost every type of ecosystem. Researchers who do recognize their importance often struggle to include parasites using classical food-web theory, mainly due to the parasites' multiple hosts and life stages. A novel approach using compound-specific stable-isotope analysis promises to provide considerable insight into the energetic exchanges of parasite and host, which may solve some of the issues inherent in incorporating parasites using a classical approach. Understanding the role of parasites within food webs, and tracing the associated biomass transfers, are crucial to constructing new models that will expand our knowledge of food webs. This mini-review focuses on stable-isotope studies published in the past decade, and introduces compound-specific stable-isotope analysis as a powerful, but underutilized, newly developed tool that may answer many unresolved questions regarding the role of parasites in food webs.

  20. Transgenic Parasites Stably Expressing Full-Length Plasmodium falciparum Circumsporozoite Protein as a Model for Vaccine Down-Selection in Mice Using Sterile Protection as an Endpoint

    Science.gov (United States)

    Porter, Michael D.; Nicki, Jennifer; Pool, Christopher D.; DeBot, Margot; Illam, Ratish M.; Brando, Clara; Bozick, Brooke; De La Vega, Patricia; Angra, Divya; Spaccapelo, Roberta; Crisanti, Andrea; Murphy, Jittawadee R.; Bennett, Jason W.; Schwenk, Robert J.; Ockenhouse, Christian F.

    2013-01-01

    Circumsporozoite protein (CSP) of Plasmodium falciparum is a protective human malaria vaccine candidate. There is an urgent need for models that can rapidly down-select novel CSP-based vaccine candidates. In the present study, the mouse-mosquito transmission cycle of a transgenic Plasmodium berghei malaria parasite stably expressing a functional full-length P. falciparum CSP was optimized to consistently produce infective sporozoites for protection studies. A minimal sporozoite challenge dose was established, and protection was defined as the absence of blood-stage parasites 14 days after intravenous challenge. The specificity of protection was confirmed by vaccinating mice with multiple CSP constructs of differing lengths and compositions. Constructs that induced high NANP repeat-specific antibody titers in enzyme-linked immunosorbent assays were protective, and the degree of protection was dependent on the antigen dose. There was a positive correlation between antibody avidity and protection. The antibodies in the protected mice recognized the native CSP on the parasites and showed sporozoite invasion inhibitory activity. Passive transfer of anti-CSP antibodies into naive mice also induced protection. Thus, we have demonstrated the utility of a mouse efficacy model to down-select human CSP-based vaccine formulations. PMID:23536694

  1. Gastrointestinal parasite control during prepuberty improves mammary parenchyma development in Holstein heifers

    OpenAIRE

    Perri, AF; Mejía, ME; Licoff, N; Diab, SS; Formía, N; Ornstein, A; Becú-Villalobos, D; Lacau-Mengido, IM

    2013-01-01

    Parasitism during development impairs normal growth and delays the onset of puberty through altered hormone profiles, including insulin-like growth factor one (IGF-1).Asmammary gland development during prepuberty is strongly dependent on IGF-1, we determined if antiparasitic treatment during this stage of growth improved mammary gland development. One group of Holstein heifers was treated monthly, rotationally with antiparasitic drugs from birth to 70 weeks of age, a secon...

  2. Big bang in the evolution of extant malaria parasites.

    Science.gov (United States)

    Hayakawa, Toshiyuki; Culleton, Richard; Otani, Hiroto; Horii, Toshihiro; Tanabe, Kazuyuki

    2008-10-01

    Malaria parasites (genus Plasmodium) infect all classes of terrestrial vertebrates and display host specificity in their infections. It is therefore assumed that malaria parasites coevolved intimately with their hosts. Here, we propose a novel scenario of malaria parasite-host coevolution. A phylogenetic tree constructed using the malaria parasite mitochondrial genome reveals that the extant primate, rodent, bird, and reptile parasite lineages rapidly diverged from a common ancestor during an evolutionary short time period. This rapid diversification occurred long after the establishment of the primate, rodent, bird, and reptile host lineages, which implies that host-switch events contributed to the rapid diversification of extant malaria parasite lineages. Interestingly, the rapid diversification coincides with the radiation of the mammalian genera, suggesting that adaptive radiation to new mammalian hosts triggered the rapid diversification of extant malaria parasite lineages.

  3. Stress and sex in malaria parasites: Why does commitment vary?

    Science.gov (United States)

    Carter, Lucy M; Kafsack, Björn F C; Llinás, Manuel; Mideo, Nicole; Pollitt, Laura C; Reece, Sarah E

    2013-01-01

    For vector-borne parasites such as malaria, how within- and between-host processes interact to shape transmission is poorly understood. In the host, malaria parasites replicate asexually but for transmission to occur, specialized sexual stages (gametocytes) must be produced. Despite the central role that gametocytes play in disease transmission, explanations of why parasites adjust gametocyte production in response to in-host factors remain controversial. We propose that evolutionary theory developed to explain variation in reproductive effort in multicellular organisms, provides a framework to understand gametocyte investment strategies. We examine why parasites adjust investment in gametocytes according to the impact of changing conditions on their in-host survival. We then outline experiments required to determine whether plasticity in gametocyte investment enables parasites to maintain fitness in a variable environment. Gametocytes are a target for anti-malarial transmission-blocking interventions so understanding plasticity in investment is central to maximizing the success of control measures in the face of parasite evolution.

  4. Improvements in the construction of nuclear power plant

    International Nuclear Information System (INIS)

    1990-01-01

    This paper outlines activities to minimize the amount of work at a construction site by employing installation method with large size blocks and shop-assembled units, improvement in facilities such as mechanization of welding and huge roof cover which enables work in all weather conditions, and administration systems using computer for the work activity control as well as quality and progress control for construction work. These improvements are only achieved when supported by related system improvements at the design and fabrication stage, and these improvements contributed a great deal to the quality assurance and the shorter construction period. (author)

  5. Targeting channels and transporters in protozoan parasite infections

    Science.gov (United States)

    Meier, Anna; Erler, Holger; Beitz, Eric

    2018-03-01

    Infectious diseases caused by pathogenic protozoa are among the most significant causes of death in humans. Therapeutic options are scarce and massively challenged by the emergence of resistant parasite strains. Many of the current anti-parasite drugs target soluble enzymes, generate unspecific oxidative stress, or act by an unresolved mechanism within the parasite. In recent years, collections of drug-like compounds derived from large-scale phenotypic screenings, such as the malaria or pathogen box, have been made available to researchers free of charge boosting the identification of novel promising targets. Remarkably, several of the compound hits have been found to inhibit membrane proteins at the periphery of the parasites, i.e. channels and transporters for ions and metabolites. In this review, we will focus on the progress made on targeting channels and transporters at different levels and the potential for use against infections with apicomplexan parasites mainly Plasmodium spp. (malaria) and Toxoplasma gondii (toxoplasmosis), with kinetoplastids Trypanosoma brucei (sleeping sickness), Trypanosoma cruzi (Chagas disease) and Leishmania ssp. (leishmaniasis), and the amoeba Entamoeba histolytica (amoebiasis).

  6. Specific Stereoisomeric Conformations Determine the Drug Potency of Cladosporin Scaffold against Malarial Parasite.

    Science.gov (United States)

    Das, Pronay; Babbar, Palak; Malhotra, Nipun; Sharma, Manmohan; Jachak, Gorakhnath R; Gonnade, Rajesh G; Shanmugam, Dhanasekaran; Harlos, Karl; Yogavel, Manickam; Sharma, Amit; Reddy, D Srinivasa

    2018-05-21

    The dependence of drug potency on diastereomeric configurations is a key facet. Using a novel general divergent synthetic route for a three-chiral centre anti-malarial natural product cladosporin, we built its complete library of stereoisomers (cladologs) and assessed their inhibitory potential using parasite-, enzyme- and structure-based assays. We show that potency is manifest via tetrahyropyran ring conformations that are housed in the ribose binding pocket of parasite lysyl tRNA synthetase (KRS). Strikingly, drug potency between top and worst enantiomers varied 500-fold, and structures of KRS-cladolog complexes reveal that alterations at C3 and C10 are detrimental to drug potency where changes at C3 are sensed by rotameric flipping of Glutamate332. Given that scores of anti-malarial and anti-infective drugs contain chiral centers, this work provides a new foundation for focusing on inhibitor stereochemistry as a facet of anti-microbial drug development.

  7. Seroprevalences of anti-Sarcocystis neurona and anti-Neospora hughesi antibodies among healthy equids in the United States.

    Science.gov (United States)

    James, Kaitlyn E; Smith, Woutrina A; Conrad, Patricia A; Packham, Andrea E; Guerrero, Leopoldo; Ng, Mitchell; Pusterla, Nicola

    2017-06-01

    OBJECTIVE To describe the general seroprevalence of anti-Sarcocystis neurona and anti-Neospora hughesi antibodies among healthy equids by use of indirect fluorescent antibody tests and determine potential risk factors for seropositivity. DESIGN Cross-sectional study. SAMPLE Whole blood samples collected from 5,250 equids (1 sample/animal) across 18 states in the United States during October 2013. PROCEDURES Information regarding potential risk factors (geographic region, breed, primary use, sex, and age) was collected along with the blood samples. For each equid, an indirect fluorescent antibody test was used to determine serum titers of antibody against each of the 2 protozoal parasites. Mixed-effects logistic regression models were created to determine ORs for seropositivity. RESULTS The overall seroprevalence of anti-S neurona and anti-N hughesi antibodies in the tested equids was 78% and 34%, respectively. Of the equids, 31% were seropositive and 18% were seronegative for antibodies against both parasites. Factors associated with equids being seropositive for anti-S neurona antibodies were residence in the South, warmblood breed, and age > 5 years. Seroprevalence of anti-N hughesi antibodies did not differ among equids in different states across the country, but warmblood breed and age > 5 years were associated with seropositivity. CONCLUSIONS AND CLINICAL RELEVANCE With regard to risk factors for S neurona and N hughesi exposure and antibody response among tested equids, older age was not unexpected; however, the influences of warmblood breed and geographic location on seropositivity for anti-S neurona antibody but not for anti-N hughesi antibody deserve further investigation.

  8. Morphological and Molecular Descriptors of the Developmental Cycle of Babesia divergens Parasites in Human Erythrocytes.

    Directory of Open Access Journals (Sweden)

    Ingrid Rossouw

    2015-05-01

    Full Text Available Human babesiosis, especially caused by the cattle derived Babesia divergens parasite, is on the increase, resulting in renewed attentiveness to this potentially life threatening emerging zoonotic disease. The molecular mechanisms underlying the pathophysiology and intra-erythrocytic development of these parasites are poorly understood. This impedes concerted efforts aimed at the discovery of novel anti-babesiacidal agents. By applying sensitive cell biological and molecular functional genomics tools, we describe the intra-erythrocytic development cycle of B. divergens parasites from immature, mono-nucleated ring forms to bi-nucleated paired piriforms and ultimately multi-nucleated tetrads that characterizes zoonotic Babesia spp. This is further correlated for the first time to nuclear content increases during intra-erythrocytic development progression, providing insight into the part of the life cycle that occurs during human infection. High-content temporal evaluation elucidated the contribution of the different stages to life cycle progression. Moreover, molecular descriptors indicate that B. divergens parasites employ physiological adaptation to in vitro cultivation. Additionally, differential expression is observed as the parasite equilibrates its developmental stages during its life cycle. Together, this information provides the first temporal evaluation of the functional transcriptome of B. divergens parasites, information that could be useful in identifying biological processes essential to parasite survival for future anti-babesiacidal discoveries.

  9. Endoparasites of Stray Dogs in Mashhad, Khorasan Razavi Province, Northeast Iran with Special Reference to Zoonotic Parasites

    Directory of Open Access Journals (Sweden)

    Amir Adinezadeh

    2013-09-01

    Full Text Available Background: To find out different species of helminthes and blood/tissue proto­zoan parasites of stray dogs and their potential role for transmission of zoonotic species to human in Mashhad, Khorasan Razavi Province, northeast Iran, during 2008-2009.Methods: Totally, 100 stray dogs were selected among Mashhad municipal collection from different sites of the city. Internal organs were examined for any parasites. Helminthes were identified based on morphological characteristics. Smears prepared from peripheral blood as well as liver, spleen and any skin lesion were stained by Giemsa and examined microscopically. Samples obtained from spleen were aseptically cultured in three culture media including NNN, Schneider’s Drosophila (HIMEDIA and RPMI1640 (GIBCO for isolation of Leishmania spp. The titer of anti-Leishmania and anti-Toxoplasma antibodies were measured by direct agglutination test (DAT and indirect fluorescent antibody test (IFAT, respectively.Results: 84% of dogs were infected at least with one species of intestinal helminthes. The species of parasites and rate of infection were as follows: Taenia hydatigena (61%, Dipylidium caninum (46%, Mesocestoides lineatus (19%, Echinococcus granulosus (10%, Toxascaris leonina (53% and Toxocara canis (7%. Anti-Leishmania antibodies were detected by DAT in 8 dogs (8% at 1:320 titers and higher. Forty seven dogs (47% showed anti-Toxoplasma titer at 1:10 and 17 (17% showed titer of ≥1:100. No blood parasites were found in prepared blood smears.Conclusion: The high rate of parasitic infection and presence of zoonotic species

  10. Retrospective investigation of serological finding in diagnosis of parasite agents caused mass in liver

    Directory of Open Access Journals (Sweden)

    Safinaz Demirkaya

    2014-06-01

    Full Text Available Objective: Many of parasite agent cause diseases damaging the liver. The parasite infections settled the liver give rise to focal mass named as reactive hyperplasia or granulomatous reactions in this organ. Some of parasites caused focal mass in liver are cystic echinococ, Fasciola hepatica and Entamoeba histolytica. The diagnoses of these parasites which are localized to liver have been carried out with serological methods (Indirect hemagglutination (IHA, Indirect Fluorescent Antibody Technic (IFAT and ELISA (Enzyme Linked Immunosorbent Assay and radiological imaging. In this study, we was aimed to investigating of prevalence with serological methods of parasite diseases like cystic echinococcosis, fascioliasis and amebic liver abscess in patients determined preliminary diagnosis mass with radiological imaging Methods: For this study, One hundred patient’s sera were included to investigation. It were investigated E.histolytica antibody with IHA method, anti-echinococcus IgG antibody with IFAT method and anti-fasciolia hepatica IgG antibody with ELISA method in sera of patient’s determined mass preliminary diagnosis with radiological imaging. Results: It were encountered these parasite in 27% of patients who determined mass preliminary diagnosis. It was determined in 1% E.histolytica, 13% Cystic echinococcus and 13% Fasciola hepatica seropositive of patients. Conclusion: The patients detected mass preliminary in liver should be evaluated for these parasites. We believe that will not be enough only radiological imaging in identification of these parasitic infections and should definitely need to be supported with a serological test.

  11. Interaction between the solitary bee Chelostoma florisomne and its nest parasite Sapyga clavicornis - empty cells reduce the impact of parasites

    DEFF Research Database (Denmark)

    Münster-Swendsen (deceased), Mikael; Calabuig, Isabel

    2000-01-01

    Summary 1. Nesting behaviour and interactions between the bee Chelostoma florisomne (L.) (Megachilidae) and its nest parasite Sapyga clavicornis (L.) (Sapygidae) were studied through continual observations of individuals and dissections of bee nests. Protection of bee offspring is based on (1.......4% of all brood cells and, if the outermost brood cell in a nest was excluded, in front of 74.3% of inner brood cells. A vestibule closure is most often constructed in front of the outermost brood cell. 3. Following oviposition, the bee made only five flights, which together lasted 6–13 min, to construct...... a cell closure. A cell closure does not prevent the nest parasite from oviposition inside the brood cell, however, and parasite eggs deposited through the cell closure are not detected and removed by the bee. Only an additional cell closure, i.e. the formation of an empty cell, may protect a brood cell...

  12. Pitting of malaria parasites and spherocyte formation

    Directory of Open Access Journals (Sweden)

    Gichuki Charity W

    2006-07-01

    Full Text Available Abstract Background A high prevalence of spherocytes was detected in blood smears of children enrolled in a case control study conducted in the malaria holoendemic Lake Victoria basin. It was speculated that the spherocytes reflect intraerythrocytic removal of malarial parasites with a concurrent removal of RBC membrane through a process analogous to pitting of intraerythrocytic inclusion bodies. Pitting and re-circulation of RBCs devoid of malaria parasites could be a host mechanism for parasite clearance while minimizing the anaemia that would occur were the entire parasitized RBC removed. The prior demonstration of RBCs containing ring-infected erythrocyte surface antigen (pf 155 or RESA but no intracellular parasites, support the idea of pitting. Methods An in vitro model was developed to examine the phenomenon of pitting and spherocyte formation in Plasmodium falciparum infected RBCs (iRBC co-incubated with human macrophages. In vivo application of this model was evaluated using blood specimens from patients attending Kisumu Ditrict Hospital. RBCs were probed with anti-RESA monoclonal antibody and a DNA stain (propidium iodide. Flow cytometry and fluorescent microscopy was used to compare RBCs containing both the antigen and the parasites to those that were only RESA positive. Results Co-incubation of iRBC and tumor necrosis factor-alpha activated macrophages led to pitting (14% ± 1.31% macrophages with engulfed trophozoites as opposed to erythrophagocytosis (5.33% ± 0.95% (P Conclusion It is proposed that in malaria holoendemic areas where prevalence of asexual stage parasites approaches 100% in children, RBCs with pitted parasites are re-circulated and pitting may produce spherocytes.

  13. Improving Indonesian Construction Consulting Services

    Directory of Open Access Journals (Sweden)

    Rizal Z. Tamin

    2015-05-01

    Full Text Available Indonesian construction consulting services are facing a complex problem in fulfilling the nation’s expectations regarding high quality infrastructure development and the construction industry’s competitiveness. A study of this problem and a formulation of solutions to improve the situation are presented in this paper. A survey was carried out in Jakarta, West Java, East Java, and North Sumatra provinces to collect data related to this problem. A focus group discussion and a workshop with all stakeholders were conducted to formulate improvement actions that need to be taken. It was revealed that the problems faced include, among others, the limited number of professional engineers compared to the number of national consultancy companies, the uneven distribution of engineers in Indonesian regions, an imperfect procurement system, and low-quality work output in general. Recommended actions include improvement of the government’s role in consulting services nurturing and facilitation, development of partnerships, and amelioration of the professional engineer and consultant certification system.

  14. Parasitic helminths: new weapons against immunological disorders.

    Science.gov (United States)

    Osada, Yoshio; Kanazawa, Tamotsu

    2010-01-01

    The prevalence of allergic and autoimmune diseases is increasing in developed countries, possibly due to reduced exposure to microorganisms in childhood (hygiene hypothesis). Epidemiological and experimental evidence in support of this hypothesis is accumulating. In this context, parasitic helminths are now important candidates for antiallergic/anti-inflammatory agents. Here we summarize antiallergic/anti-inflammatory effects of helminths together along with our own study of the effects of Schistosoma mansoni on Th17-dependent experimental arthritis. We also discuss possible mechanisms of helminth-induced suppression according to the recent advances of immunology.

  15. Parasitic Helminths: New Weapons against Immunological Disorders

    Directory of Open Access Journals (Sweden)

    Yoshio Osada

    2010-01-01

    Full Text Available The prevalence of allergic and autoimmune diseases is increasing in developed countries, possibly due to reduced exposure to microorganisms in childhood (hygiene hypothesis. Epidemiological and experimental evidence in support of this hypothesis is accumulating. In this context, parasitic helminths are now important candidates for antiallergic/anti-inflammatory agents. Here we summarize antiallergic/anti-inflammatory effects of helminths together along with our own study of the effects of Schistosoma mansoni on Th17-dependent experimental arthritis. We also discuss possible mechanisms of helminth-induced suppression according to the recent advances of immunology.

  16. Cryptosporidium and other intestinal parasitic infections among HIV patients in southern Ethiopia: significance of improved HIV-related care.

    Science.gov (United States)

    Shimelis, Techalew; Tassachew, Yayehyirad; Lambiyo, Tariku

    2016-05-10

    Intestinal parasitic infections are known to cause gastroenteritis, leading to higher morbidity and mortality, particularly in people living with HIV/AIDS. This study aimed to determine the prevalence of Cryptosporidium and other intestinal parasitic infections among HIV patients receiving care at a hospital in Ethiopia where previous available baseline data helps assess if improved HIV-related care has reduced infection rates. A cross-sectional study was conducted at Hawassa University Hospital in southern Ethiopia from May, 2013 to March, 2014. A consecutive sample of 491 HIV- infected patients with diarrhea or a CD4 T cell count intestinal parasites. The study was approved by the Institutional Review Board of the College of Medicine and Health Sciences, Hawassa University. Physicians managed participants found to be infected with any pathogenic intestinal parasite. The overall prevalence of intestinal parasitic infections among the study population was 35.8 %. The most prevalent parasites were Cryptosporidium (13.2 %), followed by Entamoeba histolytica/dispar (10.2 %), and Giardia lamblia (7.9 %). The rate of single and multiple infections were 25.5 and 10.3 %, respectively. Patients with a CD4 T cell count intestinal parasitic infection or cryptosporidiosis compared to those with counts ≥ 200 cells/μl, but with some type of diarrhea. The study shows high prevalence of intestinal parasitic infections in the study population. However, the results in the current report are significantly lower compared to previous findings in the same hospital. The observed lower infection rate is encouraging and supports the need to strengthen and sustain the existing intervention measures in order to further reduce intestinal parasitic infections in people living with HIV/AIDS.

  17. Seroprevalence rates of antibodies against Leishmania infantum and other protozoan and rickettsial parasites in dogs Soroprevalência de anticorpos contra Leishmania infantum e outras espécies de protozoários e rickettsia em cães

    Directory of Open Access Journals (Sweden)

    Silvana de Cássia Paulan

    2013-03-01

    Full Text Available Canine visceral leishmaniasis (CVL is caused by the protozoan Leishmania infantum, which infects dogs and humans in many regions of Brazil. The present study involved an indirect fluorescent antibody test (IFAT to analyze L. infantum, Ehrlichia spp., Babesia canis, Toxoplasma gondii and Neospora caninum infection rates in serum samples from 93 dogs in a rural settlement in Ilha Solteira, SP, Brazil. The seroprevalence rates of anti-L. infantum, anti-Ehrlichia, anti-B. canis, anti-T. gondii and anti-N. caninum antibodies were 37.6%, 75.3%, 72%, 47.3% and 6.4%, respectively. In addition to IFAT, direct microscopic examination of popliteal lymph node aspirates revealed 26.9% of CVL positive dogs. Serological tests revealed that 17.2% of the dogs were seropositive for a single parasite, 29% for two parasites, 33% for three, 16.1% for four, and 1.1% for five parasites, while 3.2% were seronegative for five parasites. The presence of antibodies against these parasites in serum samples from dogs confirmed their exposure to these parasites in this rural area. Because of the potential zoonotic risk of these diseases, mainly leishmaniasis, ehrlichiosis and toxoplasmosis, special attention should focus on programs for the improvement of diagnostic assays and control measures against these parasites.Leishmaniose Visceral Canina (LVC é causada pelo protozoário Leishmania infantum, podendo infectar cães e humanos em várias regiões do Brasil. O presente estudo teve por objetivo realizar a reação de imunofluorescência indireta (RIFI para analisar os índices de infecção parasitária para L. infantum, Ehrlichia spp., Babesia canis, Toxoplasma gondii e Neospora caninum, em 93 amostras de soro de cães de um assentamento rural no município de Ilha Solteira, SP, Brasil. A taxa de soroprevalência de cães com anticorpos anti-L. infantum, anti-Ehrlichia, anti-B. canis, anti-T. gondii e anti-N. caninum foi de 37,6%, 75,3%, 72%, 47,3% e 6

  18. Collective defence portfolios of ant hosts shift with social parasite pressure.

    Science.gov (United States)

    Jongepier, Evelien; Kleeberg, Isabelle; Job, Sylwester; Foitzik, Susanne

    2014-09-22

    Host defences become increasingly costly as parasites breach successive lines of defence. Because selection favours hosts that successfully resist parasitism at the lowest possible cost, escalating coevolutionary arms races are likely to drive host defence portfolios towards ever more expensive strategies. We investigated the interplay between host defence portfolios and social parasite pressure by comparing 17 populations of two Temnothorax ant species. When successful, collective aggression not only prevents parasitation but also spares host colonies the cost of searching for and moving to a new nest site. However, once parasites breach the host's nest defence, host colonies should resort to flight as the more beneficial resistance strategy. We show that under low parasite pressure, host colonies more likely responded to an intruding Protomognathus americanus slavemaker with collective aggression, which prevented the slavemaker from escaping and potentially recruiting nest-mates. However, as parasite pressure increased, ant colonies of both host species became more likely to flee rather than to fight. We conclude that host defence portfolios shift consistently with social parasite pressure, which is in accordance with the degeneration of frontline defences and the evolution of subsequent anti-parasite strategies often invoked in hosts of brood parasites. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  19. Sirtuins of parasitic protozoa: In search of function(s)

    Science.gov (United States)

    Religa, Agnieszka A.; Waters, Andrew P.

    2012-01-01

    The SIR2 family of NAD+-dependent protein deacetylases, collectively called sirtuins, has been of central interest due to their proposed roles in life-span regulation and ageing. Sirtuins are one group of environment sensors of a cell interpreting external information and orchestrating internal responses at the sub-cellular level, through participation in gene regulation mechanisms. Remarkably conserved across all kingdoms of life SIR2 proteins in several protozoan parasites appear to have both conserved and intriguing unique functions. This review summarises our current knowledge of the members of the sirtuin families in Apicomplexa, including Plasmodium, and other protozoan parasites such as Trypanosoma and Leishmania. The wide diversity of processes regulated by SIR2 proteins makes them targets worthy of exploitation in anti-parasitic therapies. PMID:22906508

  20. Accuracy Improvement of Real-Time Location Tracking for Construction Workers

    Directory of Open Access Journals (Sweden)

    Hyunsoo Kim

    2018-05-01

    Full Text Available Extensive research has been conducted on the real-time locating system (RTLS for tracking construction components, including workers, equipment, and materials, in order to improve construction performance (e.g., productivity improvement or accident prevention. In order to prevent safety accidents and make more sustainable construction job sites, the higher accuracy of RTLS is required. To improve the accuracy of RTLS in construction projects, this paper presents a RTLS using radio frequency identification (RFID. For this goal, this paper develops a location tracking error mitigation algorithm and presents the concept of using assistant tags. The applicability and effectiveness of the developed RTLS are tested under eight different construction environments and the test results confirm the system’s strong potential for improving the accuracy of real-time location tracking in construction projects, thus enhancing construction performance.

  1. Improved DEA Cross Efficiency Evaluation Method Based on Ideal and Anti-Ideal Points

    Directory of Open Access Journals (Sweden)

    Qiang Hou

    2018-01-01

    Full Text Available A new model is introduced in the process of evaluating efficiency value of decision making units (DMUs through data envelopment analysis (DEA method. Two virtual DMUs called ideal point DMU and anti-ideal point DMU are combined to form a comprehensive model based on the DEA method. The ideal point DMU is taking self-assessment system according to efficiency concept. The anti-ideal point DMU is taking other-assessment system according to fairness concept. The two distinctive ideal point models are introduced to the DEA method and combined through using variance ration. From the new model, a reasonable result can be obtained. Numerical examples are provided to illustrate the new constructed model and certify the rationality of the constructed model through relevant analysis with the traditional DEA model.

  2. Parasites in food webs: the ultimate missing links

    Science.gov (United States)

    Lafferty, Kevin D.; Allesina, Stefano; Arim, Matias; Briggs, Cherie J.; De Leo, Giulio A.; Dobson, Andrew P.; Dunne, Jennifer A.; Johnson, Pieter T.J.; Kuris, Armand M.; Marcogliese, David J.; Martinez, Neo D.; Memmott, Jane; Marquet, Pablo A.; McLaughlin, John P.; Mordecai, Eerin A.; Pascual, Mercedes; Poulin, Robert; Thieltges, David W.

    2008-01-01

    Parasitism is the most common consumer strategy among organisms, yet only recently has there been a call for the inclusion of infectious disease agents in food webs. The value of this effort hinges on whether parasites affect food-web properties. Increasing evidence suggests that parasites have the potential to uniquely alter food-web topology in terms of chain length, connectance and robustness. In addition, parasites might affect food-web stability, interaction strength and energy flow. Food-web structure also affects infectious disease dynamics because parasites depend on the ecological networks in which they live. Empirically, incorporating parasites into food webs is straightforward. We may start with existing food webs and add parasites as nodes, or we may try to build food webs around systems for which we already have a good understanding of infectious processes. In the future, perhaps researchers will add parasites while they construct food webs. Less clear is how food-web theory can accommodate parasites. This is a deep and central problem in theoretical biology and applied mathematics. For instance, is representing parasites with complex life cycles as a single node equivalent to representing other species with ontogenetic niche shifts as a single node? Can parasitism fit into fundamental frameworks such as the niche model? Can we integrate infectious disease models into the emerging field of dynamic food-web modelling? Future progress will benefit from interdisciplinary collaborations between ecologists and infectious disease biologists.

  3. Parasitic infection improves survival from septic peritonitis by enhancing mast cell responses to bacteria in mice.

    Directory of Open Access Journals (Sweden)

    Rachel E Sutherland

    Full Text Available Mammals are serially infected with a variety of microorganisms, including bacteria and parasites. Each infection reprograms the immune system's responses to re-exposure and potentially alters responses to first-time infection by different microorganisms. To examine whether infection with a metazoan parasite modulates host responses to subsequent bacterial infection, mice were infected with the hookworm-like intestinal nematode Nippostrongylus brasiliensis, followed in 2-4 weeks by peritoneal injection of the pathogenic bacterium Klebsiella pneumoniae. Survival from Klebsiella peritonitis two weeks after parasite infection was better in Nippostrongylus-infected animals than in unparasitized mice, with Nippostrongylus-infected mice having fewer peritoneal bacteria, more neutrophils, and higher levels of protective interleukin 6. The improved survival of Nippostrongylus-infected mice depends on IL-4 because the survival benefit is lost in mice lacking IL-4. Because mast cells protect mice from Klebsiella peritonitis, we examined responses in mast cell-deficient Kit(W-sh/Kit(W-sh mice, in which parasitosis failed to improve survival from Klebsiella peritonitis. However, adoptive transfer of cultured mast cells to Kit(W-sh/Kit(W-sh mice restored survival benefits of parasitosis. These results show that recent infection with Nippostrongylus brasiliensis protects mice from Klebsiella peritonitis by modulating mast cell contributions to host defense, and suggest more generally that parasitosis can yield survival advantages to a bacterially infected host.

  4. Effective and specific in planta RNAi in cyst nematodes: expression interference of four parasitism genes reduces parasitic success.

    Science.gov (United States)

    Sindhu, Anoop S; Maier, Tom R; Mitchum, Melissa G; Hussey, Richard S; Davis, Eric L; Baum, Thomas J

    2009-01-01

    Cyst nematodes are highly evolved sedentary plant endoparasites that use parasitism proteins injected through the stylet into host tissues to successfully parasitize plants. These secretory proteins likely are essential for parasitism as they are involved in a variety of parasitic events leading to the establishment of specialized feeding cells required by the nematode to obtain nourishment. With the advent of RNA interference (RNAi) technology and the demonstration of host-induced gene silencing in parasites, a new strategy to control pests and pathogens has become available, particularly in root-knot nematodes. Plant host-induced silencing of cyst nematode genes so far has had only limited success but similarly should disrupt the parasitic cycle and render the host plant resistant. Additional in planta RNAi data for cyst nematodes are being provided by targeting four parasitism genes through host-induced RNAi gene silencing in transgenic Arabidopsis thaliana, which is a host for the sugar beet cyst nematode Heterodera schachtii. Here it is reported that mRNA abundances of targeted nematode genes were specifically reduced in nematodes feeding on plants expressing corresponding RNAi constructs. Furthermore, this host-induced RNAi of all four nematode parasitism genes led to a reduction in the number of mature nematode females. Although no complete resistance was observed, the reduction of developing females ranged from 23% to 64% in different RNAi lines. These observations demonstrate the relevance of the targeted parasitism genes during the nematode life cycle and, potentially more importantly, suggest that a viable level of resistance in crop plants may be accomplished in the future using this technology against cyst nematodes.

  5. Effects of road salt on larval amphibian susceptibility to parasitism through behavior and immunocompetence.

    Science.gov (United States)

    Milotic, Dino; Milotic, Marin; Koprivnikar, Janet

    2017-08-01

    Large quantities of road salts are used for de-icing in temperate climates but often leach into aquatic ecosystems where they can cause harm to inhabitants, including reduced growth and survival. However, the implications of road salt exposure for aquatic animal susceptibility to pathogens and parasites have not yet been examined even though infectious diseases can significantly contribute to wildlife population declines. Through a field survey, we found a range of NaCl concentrations (50-560mg/L) in ponds known to contain larval amphibians, with lower levels found in sites close to gravel- rather than hard-surfaced roads. We then investigated how chronic exposure to environmentally-realistic levels of road salt (up to 1140mg/L) affected susceptibility to infection by trematode parasites (helminths) in larval stages of two amphibian species (Lithobates sylvaticus - wood frogs, and L. pipiens - northern leopard frogs) by considering effects on host anti-parasite behavior and white blood cell profiles. Wood frogs exposed to road salt had higher parasite loads, and also exhibited reduced anti-parasite behavior in these conditions. In contrast, infection intensity in northern leopard frogs had a non-monotonic response to road salts even though lymphocytes were only elevated at the highest concentration. Our results indicate the potential for chronic road salt exposure to affect larval amphibian susceptibility to pathogenic parasites through alterations of behavior and immunocompetence, with further studies needed at higher concentrations, as well as that of road salts on free-living parasite infectious stages. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Hairworm anti-predator strategy: a study of causes and consequences

    DEFF Research Database (Denmark)

    Ponton, Fleur; Lebarbenchon, Camille; Lefèvre, Thierry

    2006-01-01

    One of the most fascinating anti-predator responses displayed by parasites is that of hairworms (Nematomorpha). Following the ingestion of the insect host by fish or frogs, the parasitic worm is able to actively exit both its host and the gut of the predator. Using as a model the hairworm, Parago...

  7. Discussion on anti-flood renovation of operational nuclear power plants

    International Nuclear Information System (INIS)

    Chen Jiangang; Chen Haiqiao; Zhang Lihan; Wang Sen; Liu Shifeng

    2014-01-01

    The design of nuclear power plants on anti-flood performance was only based on design basis condition in China. The Fukushima nuclear accident revealed the possibility of suffering flood under beyond design basis condition, which caused the continuously deterioration of Fukushima nuclear accident. After the accident, China national nuclear safety regulators proposed new requirements on performance of anti-flood of nuclear power plants. Then, Qinshan Phase II carried out research of anti-flood technology. This paper introduced the background, research and development of anti-flood renovation technology for important safety buildings of Qinshan Phase II, and discussed the necessary for improvement of anti-flood capacity of nuclear power plants and relative measures in China, which is helpful to improve anti-flood performance of operational nuclear power plants and nuclear power plants under construction. (authors)

  8. Approach to improve construction management utilizing information technology

    International Nuclear Information System (INIS)

    Lee, Woo Bang; Moon, Jin Yeong

    2003-01-01

    Korea Hydro and Nuclear Power (KHNP) has been managed Nuclear Power Plant (NPP) construction projects including basic project planning, design, procurement, construction and start-up for nearly 30 years, and taken the leading role in the self-reliance program for constructing NPP. To maintain its leading position of construction technology and export it to other countries, it is more likely required to build the strong and competitive business management system to improve internal business efficiency and transparency, and also to respond to the change of external business circumstances such as electricity market opening. KHNP is implementing Enterprise Resource Planning (ERP) System as a business innovation tool to improve business efficiency, which changes the way of performing work from organizational system to process-oriented system in order to optimize the company resources to achieve above goals. This change should be made based on the results of performing Business Process Re-engineering (BPR) to maximize overall business efficiency. For the construction project management area, the establishment of Integrated Construction Information Sharing System based on Information Technology (IT) is the most important part. It makes possible to build collaboration system with 'Win-Win strategy' between the project owner and all related entities and to contribute to secure transparency and cut the project cost down. We would like to introduce our NPP Construction Project Management System, Infrastructure for Information System, Information Sharing System among construction related entities and Implementation Practices in this paper and also include the suggestions on our customary practice and subject that should be improved

  9. Antiparasitic effects induced by polyclonal IgY antibodies anti-phospholipase A2 from Bothrops pauloensis venom.

    Science.gov (United States)

    Borges, Isabela Pacheco; Silva, Mariana Ferreira; Santiago, Fernanda Maria; de Faria, Lucas Silva; Júnior, Álvaro Ferreira; da Silva, Rafaela José; Costa, Mônica Soares; de Freitas, Vitor; Yoneyama, Kelly Aparecida Geraldo; Ferro, Eloísa Amália Vieira; Lopes, Daiana Silva; Rodrigues, Renata Santos; de Melo Rodrigues, Veridiana

    2018-06-01

    Activities of phospholipases (PLAs) have been linked to pathogenesis in various microorganisms, and implicated in cell invasion and so the interest in these enzymes as potential targets that could contribute to the control of parasite survival and proliferation. Chicken eggs immunized with BnSP-7, a Lys49 phospholipase A 2 (PLA 2 ) homologue from Bothrops pauloensis snake venom, represent an excellent source of polyclonal antibodies with potential inhibitory activity on parasite PLA s. Herein, we report the production, characterization and anti-parasitic effect of IgY antibodies from egg yolks of hens immunized with BnSP-7. Produced antibodies presented increasing avidity and affinity for antigenic toxin epitopes throughout immunization, attaining a plateau after 4weeks. Pooled egg yolks-purified anti-BnSP-7 IgY antibodies were able to specifically recognize different PLA 2 s from Bothrops pauloensis and Bothrops jararacussu venom. Antibodies also neutralized BnSP-7 cytotoxic activity in C2C12 cells. Also, the antibodies recognized targets in Leishmania (Leishmania) amazonensis and Toxoplasma gondii extracts by ELISA and immunofluorescence assays. Anti-BnSP-7 IgY antibodies were cytotoxic to T. gondii tachyzoite and L. (L.) amazonensis promastigotes, and were able to decrease proliferation of both parasites treated before infection. These data suggest that the anti-BnSP-7 IgY is an important tool for discovering new parasite targets and blocking parasitic effects. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Anti-Plasmodium activity of ceramide analogs

    Directory of Open Access Journals (Sweden)

    Gatt Shimon

    2004-12-01

    Full Text Available Abstract Background Sphingolipids are key molecules regulating many essential functions in eukaryotic cells and ceramide plays a central role in sphingolipid metabolism. A sphingolipid metabolism occurs in the intraerythrocytic stages of Plasmodium falciparum and is associated with essential biological processes. It constitutes an attractive and potential target for the development of new antimalarial drugs. Methods The anti-Plasmodium activity of a series of ceramide analogs containing different linkages (amide, methylene or thiourea linkages between the fatty acid part of ceramide and the sphingoid core was investigated in culture and compared to the sphingolipid analog PPMP (d,1-threo-1-phenyl-2-palmitoylamino-3-morpholino-1-propanol. This analog is known to inhibit the parasite sphingomyelin synthase activity and block parasite development by preventing the formation of the tubovesicular network that extends from the parasitophorous vacuole to the red cell membrane and delivers essential extracellular nutrients to the parasite. Results Analogs containing methylene linkage showed a considerably higher anti-Plasmodium activity (IC50 in the low nanomolar range than PPMP and their counterparts with a natural amide linkage (IC50 in the micromolar range. The methylene analogs blocked irreversibly P. falciparum development leading to parasite eradication in contrast to PPMP whose effect is cytostatic. A high sensitivity of action towards the parasite was observed when compared to their effect on the human MRC-5 cell growth. The toxicity towards parasites did not correlate with the inhibition by methylene analogs of the parasite sphingomyelin synthase activity and the tubovesicular network formation, indicating that this enzyme is not their primary target. Conclusions It has been shown that ceramide analogs were potent inhibitors of P. falciparum growth in culture. Interestingly, the nature of the linkage between the fatty acid part and the

  11. Peroxisomes in parasitic protists.

    Science.gov (United States)

    Gabaldón, Toni; Ginger, Michael L; Michels, Paul A M

    Representatives of all major lineages of eukaryotes contain peroxisomes with similar morphology and mode of biogenesis, indicating a monophyletic origin of the organelles within the common ancestor of all eukaryotes. Peroxisomes originated from the endoplasmic reticulum, but despite a common origin and shared morphological features, peroxisomes from different organisms show a remarkable diversity of enzyme content and the metabolic processes present can vary dependent on nutritional or developmental conditions. A common characteristic and probable evolutionary driver for the origin of the organelle is an involvement in lipid metabolism, notably H 2 O 2 -dependent fatty-acid oxidation. Subsequent evolution of the organelle in different lineages involved multiple acquisitions of metabolic processes-often involving retargeting enzymes from other cell compartments-and losses. Information about peroxisomes in protists is still scarce, but available evidence, including new bioinformatics data reported here, indicate striking diversity amongst free-living and parasitic protists from different phylogenetic supergroups. Peroxisomes in only some protists show major involvement in H 2 O 2 -dependent metabolism, as in peroxisomes of mammalian, plant and fungal cells. Compartmentalization of glycolytic and gluconeogenic enzymes inside peroxisomes is characteristic of kinetoplastids and diplonemids, where the organelles are hence called glycosomes, whereas several other excavate parasites (Giardia, Trichomonas) have lost peroxisomes. Amongst alveolates and amoebozoans patterns of peroxisome loss are more complicated. Often, a link is apparent between the niches occupied by the parasitic protists, nutrient availability, and the absence of the organelles or their presence with a specific enzymatic content. In trypanosomatids, essentiality of peroxisomes may be considered for use in anti-parasite drug discovery. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Improved anti-stiction coating of SU-8 molds

    DEFF Research Database (Denmark)

    Lange, Jacob Moresco; Clausen, Casper Hyttel; Svendsen, Winnie Edith

    2010-01-01

    of the epoxy groups by oxygen plasma or sulfuric acid improves the deposition of FDTS. The deposition of FDTS on acid-activated and untreated SU-8 gave an identical well performing anti-stiction coating, as opposed to oxygen plasma activated surface which resulted in a poor FDTS coverage. In this paper...

  13. Improving the Quality of Constructive Peer Feedback

    Science.gov (United States)

    Waggoner Denton, Ashley

    2018-01-01

    This article presents some simple strategies that instructors can use to improve the quality of the feedback students provide each other during a peer review activity. Briefly, I recommend that emphasis be placed solely on the provision of constructive comments, and that in order to qualify as constructive, a comment must: (1) identify a specific…

  14. Nanostructured composite films of ceria nanoparticles with anti-UV and scratch protection properties constructed using a layer-by-layer strategy

    International Nuclear Information System (INIS)

    Zhang, Songsong; Li, Jie; Guo, Xianpeng; Liu, Lianhe; Wei, Hao; Zhang, Yingwei

    2016-01-01

    Highlights: • The fabrication of LbL multilayers used functional nanoparticles. • The film structure can be controlled in the nanoscopic range. • The constructed multilayers were transparent in the visible spectral region and presented anti-UV properties. • The multilayers presented scratch protection properties. - Abstract: Rare earth cerium oxide (ceria) nanoparticles have attracted extensive research attention due to their advantageous anti-UV and anti-scratch properties. However, a general and facile method for the fabrication of composite films using ceria and possessing these advantages is still lacking. Here, we report the fabrication of multilayers of ceria and polymeric species poly(styrene sulfonate) (PSS) and poly(diallyl-dimethyl ammonium) (PDDA) via the layer-by-layer deposition strategy. The thickness of the multilayers increased linearly with the number of bilayers, indicating accurate control of the film structure in the nanoscopic range. The constructed multilayers were transparent in the visible spectral region and at the same time presented anti-UV properties. In addition, the multilayers also presented scratch protection properties.

  15. Anti-trypanosomal activity of cationic N-heterocyclic carbene gold(I) complexes.

    Science.gov (United States)

    Winter, Isabel; Lockhauserbäumer, Julia; Lallinger-Kube, Gertrud; Schobert, Rainer; Ersfeld, Klaus; Biersack, Bernhard

    2017-06-01

    Two gold(I) N-heterocyclic carbene complexes 1a and 1b were tested for their anti-trypanosomal activity against Trypanosoma brucei parasites. Both gold compounds exhibited excellent anti-trypanosomal activity (IC 50 =0.9-3.0nM). The effects of the gold complexes 1a and 1b on the T. b. brucei cytoskeleton were evaluated. Rapid detachment of the flagellum from the cell body occurred after treatment with the gold complexes. In addition, a quick and complete degeneration of the parasitic cytoskeleton was induced by the gold complexes, only the microtubules of the detached flagellum remained intact. Both gold compounds 1a and 1b feature selective anti-trypanosomal agents and were distinctly more active against T. b. brucei cells than against human HeLa cells. Thus, the gold complexes 1a and 1b feature promising drug candidates for the treatment of trypanosome infections such as sleeping sickness (human African Trypanosomiasis caused by Trypanosoma brucei parasites). Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Anti-TNF-α biotherapies

    DEFF Research Database (Denmark)

    Bendtzen, Klaus

    2012-01-01

    This article discusses the rationale behind recommending immunopharmacological guidance of long-term therapies with genetically engineered anti-TNF-α immunoglobulin constructs. Arguments why therapeutic decision-making should not rely on clinical outcome alone are presented. Central...... to this is that the use of theranostics (i.e., monitoring circulating levels of functional anti-TNF-α drugs and antidrug antibodies) would markedly improve treatment because therapies can be tailored to individual patients and provide more effective and economical long-term therapies with minimal risk of side effects....... Large-scale immunopharmacological knowledge of how patients 'handle' TNF-α biopharmaceuticals would also help industry develop more effective and safer TNF-α inhibitors....

  17. The design and research of anti-color-noise chaos M-ary communication system

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Yongqing, E-mail: fuyongqing@hrbeu.edu.cn; Li, Xingyuan; Li, Yanan [College of information and Communication Engineering, Harbin Engineering University, Harbin 150001 (China); Zhang, Lin [College of Underwater Acoustic Engineering, Harbin Engineering University, Harbin 150001 (China)

    2016-03-15

    Previously a novel chaos M-ary digital communication method based on spatiotemporal chaos Hamilton oscillator has been proposed. Without chaos synchronization circumstance, it has performance improvement in bandwidth efficiency, transmission efficiency and anti-white-noise performance compared with traditional communication method. In this paper, the channel noise influence on chaotic modulation signals and the construction problem of anti-color-noise chaotic M-ary communication system are studied. The formula of zone partition demodulator’s boundary in additive white Gaussian noise is derived, besides, the problem about how to determine the boundary of zone partition demodulator in additive color noise is deeply studied; Then an approach on constructing anti-color-noise chaos M-ary communication system is proposed, in which a pre-distortion filter is added after the chaos baseband modulator in the transmitter and whitening filter is added before zone partition demodulator in the receiver. Finally, the chaos M-ary communication system based on Hamilton oscillator is constructed and simulated in different channel noise. The result shows that the proposed method in this paper can improve the anti-color-noise performance of the whole communication system compared with the former system, and it has better anti-fading and resisting disturbance performance than Quadrature Phase Shift Keying system.

  18. The design and research of anti-color-noise chaos M-ary communication system

    International Nuclear Information System (INIS)

    Fu, Yongqing; Li, Xingyuan; Li, Yanan; Zhang, Lin

    2016-01-01

    Previously a novel chaos M-ary digital communication method based on spatiotemporal chaos Hamilton oscillator has been proposed. Without chaos synchronization circumstance, it has performance improvement in bandwidth efficiency, transmission efficiency and anti-white-noise performance compared with traditional communication method. In this paper, the channel noise influence on chaotic modulation signals and the construction problem of anti-color-noise chaotic M-ary communication system are studied. The formula of zone partition demodulator’s boundary in additive white Gaussian noise is derived, besides, the problem about how to determine the boundary of zone partition demodulator in additive color noise is deeply studied; Then an approach on constructing anti-color-noise chaos M-ary communication system is proposed, in which a pre-distortion filter is added after the chaos baseband modulator in the transmitter and whitening filter is added before zone partition demodulator in the receiver. Finally, the chaos M-ary communication system based on Hamilton oscillator is constructed and simulated in different channel noise. The result shows that the proposed method in this paper can improve the anti-color-noise performance of the whole communication system compared with the former system, and it has better anti-fading and resisting disturbance performance than Quadrature Phase Shift Keying system.

  19. Anti-corrosion coatings in mine construction

    Energy Technology Data Exchange (ETDEWEB)

    Muchnik, P.I.; Plishevoi, A.N.; Semikina, N.I.

    1984-04-01

    This paper describes developments in methods used to protect mine equipment against corrosion. Paint/varnish materials such as EhF-1219 will protect metallic structures above ground for 8 years with a single coat (100-120 microns), and 2 coats will protect underground equipment (even in wet conditions) for up to 10 years. Various rust modifiers are also in use, based on oak tanning extract, oxalic acid and orthophosphoric acid in combination with zinc or aluminium phosphate. VNIIOMShS has developed an improved rust modifier which is applied with brush or spray and left to dry for 24 hours at 18-23 C. Experience has shown that paint/varnish coatings may be employed to give protection on equipment with a planned service life of up to 25 years, while for longer service lives zinc or combined coatings are preferred. VNIIOMShS has also developed methods for applying paint/varnish materials on tall structures without suspended gear, and for the preparation of surfaces for anti-corrosion coatings. (In Russian)

  20. On improving the NPP construction long-term planning

    International Nuclear Information System (INIS)

    Solov'ev, M.M.

    1980-01-01

    General approaches to solving the problems of long-term planning of the construction-mounting work volume and introduction of power capacities at different paces of power unit commission and norms of construction time are considered. Problems associated with location and development of subsidiary industries providing NPP construction are discussed. It is shown that decrease of WWER-1000 reactor type NPP construction time from 24 to 12 months results in reduction of required high-skilled engineers, managerial staff, unique construction mechanisms and engines as well as in improvement of conditions for conducting measures on work arrangement during preparation of construction industry and mounting of the first assemblies

  1. [Establishment of response system to emergency parasitic disease affairs in China].

    Science.gov (United States)

    Chun-Li, C; Le-Ping, S; Qing-Biao, H; Bian-Li, X U; Bo, Z; Jian-Bing, L; Dan-Dan, L; Shi-Zhu, L I; Oning, X; Xiao-Nong, Z

    2017-08-14

    China's prevention and control of parasitic diseases has made remarkable achievements. However, the prevalence and transmission of parasitic diseases is impacted by the complicated natural and social factors of environment, natural disasters, population movements, and so on. Therefore, there are still the risks of the outbreak of emergency parasitic diseases affairs, which may affect the control effectiveness of parasitic diseases and endanger the social stability seriously. In this article, we aim at the analysis of typical cases of emergency parasitic disease affairs and their impacts on public health security in China in recently years, and we also elaborate the disposal characteristics of emergency parasitic disease affairs, and propose the establishment of response system to emergency parasitic disease affairs in China, including the organizational structure and response flow path, and in addition, point out that, in the future, we should strengthen the system construction and measures of the response system to emergency parasitic disease affairs, so as to control the risk and harm of parasitic disease spread as much as possible and to realize the early intervention and proper disposal of emergency parasitic disease affairs.

  2. Fitness of Leishmania donovani parasites resistant to drug combinations.

    Directory of Open Access Journals (Sweden)

    Raquel García-Hernández

    2015-04-01

    Full Text Available Drug resistance represents one of the main problems for the use of chemotherapy to treat leishmaniasis. Additionally, it could provide some advantages to Leishmania parasites, such as a higher capacity to survive in stress conditions. In this work, in mixed populations of Leishmania donovani parasites, we have analyzed whether experimentally resistant lines to one or two combined anti-leishmanial drugs better support the stress conditions than a susceptible line expressing luciferase (Luc line. In the absence of stress, none of the Leishmania lines showed growth advantage relative to the other when mixed at a 1:1 parasite ratio. However, when promastigotes from resistant lines and the Luc line were mixed and exposed to different stresses, we observed that the resistant lines are more tolerant of different stress conditions: nutrient starvation and heat shock-pH stress. Further to this, we observed that intracellular amastigotes from resistant lines present a higher capacity to survive inside the macrophages than those of the control line. These results suggest that resistant parasites acquire an overall fitness increase and that resistance to drug combinations presents significant differences in their fitness capacity versus single-drug resistant parasites, particularly in intracellular amastigotes. These results contribute to the assessment of the possible impact of drug resistance on leishmaniasis control programs.

  3. Secondary Defense Chemicals in Milkweed Reduce Parasite Infection in Monarch Butterflies, Danaus plexippus.

    Science.gov (United States)

    Gowler, Camden D; Leon, Kristoffer E; Hunter, Mark D; de Roode, Jacobus C

    2015-06-01

    In tri-trophic systems, herbivores may benefit from their host plants in fighting parasitic infections. Plants can provide parasite resistance in two contrasting ways: either directly, by interfering with the parasite, or indirectly, by increasing herbivore immunity or health. In monarch butterflies, the larval diet of milkweed strongly influences the fitness of a common protozoan parasite. Toxic secondary plant chemicals known as cardenolides correlate strongly with parasite resistance of the host, with greater cardenolide concentrations in the larval diet leading to lower parasite growth. However, milkweed cardenolides may covary with other indices of plant quality including nutrients, and a direct experimental link between cardenolides and parasite performance has not been established. To determine if the anti-parasitic activity of milkweeds is indeed due to secondary chemicals, as opposed to nutrition, we supplemented the diet of infected and uninfected monarch larvae with milkweed latex, which contains cardenolides but no nutrients. Across three experiments, increased dietary cardenolide concentrations reduced parasite growth in infected monarchs, which consequently had longer lifespans. However, uninfected monarchs showed no differences in lifespan across treatments, confirming that cardenolide-containing latex does not increase general health. Our results suggest that cardenolides are a driving force behind plant-derived resistance in this system.

  4. Gastrointestinal parasite control during prepuberty improves mammary parenchyma development in Holstein heifers.

    Science.gov (United States)

    Perri, Adrián F; Mejía, Miguel E; Licoff, Nicolás; Diab, Santiago S; Formía, Néstor; Ornstein, Ana; Becú-Villalobos, Damasia; Lacau-Mengido, Isabel M

    2013-12-06

    Parasitism during development impairs normal growth and delays the onset of puberty through altered hormone profiles, including insulin-like growth factor one (IGF-1). As mammary gland development during prepuberty is strongly dependent on IGF-1, we determined if antiparasitic treatment during this stage of growth improved mammary gland development. One group of Holstein heifers was treated monthly, rotationally with antiparasitic drugs from birth to 70 weeks of age, a second group was untreated. Treated heifer calves had between 56% and 65% less EPG counts than untreated ones. Presence of Ostertagia, Cooperia, Haemonchus and Trichostrongylus was demonstrated. Treatment effectively advanced the onset of puberty and increased IGF-1 levels. At 20, 30, 40 and 70 weeks of age biopsies from the mammary gland were taken and histological sections were prepared and stained with hematoxylin-eosin. Pictures were analyzed to compare parenchyma area in relation to total mammary tissue between groups. Mammary samples from treated heifers had higher ratios of parenchyma/total area than untreated ones. As mammary development during prepuberty is crucial for mammary performance during lactation, these results add new evidence to the importance of gastrointestinal parasite control in heifers. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Improving Building Performance through Integrating Constructability in the Design Process

    OpenAIRE

    Ezzat Othman, Ayman Ahmed

    2011-01-01

    The traditional procurment approaches commonly adopted in construction projects and the involvement of multitude of various project participants with diverse objectives, skills and interests tended to separate design from construction.This separation obstructs contractors from providing designers with construction feedback and suggestions for design improvement, which ultimately hampers the improvement of building performance. Because of the importance of the design phase and the vit...

  6. Intestinal Parasitic Infections in HIV Infected and Non-Infected Patients in a Low HIV Prevalence Region, West-Cameroon

    Science.gov (United States)

    Nkenfou, Céline Nguefeu; Nana, Christelle Tafou; Payne, Vincent Khan

    2013-01-01

    The magnitude of intestinal parasitic infection in acquired immunodeficiency syndrome patients requires careful consideration in the developing world where poor nutrition is associated with poor hygiene and several tropical diseases. However, there have been very few studies addressing this issue in Cameroon. This study was conducted to determine the prevalence of intestinal parasitosis in HIV/AIDS patients in Dschang -Cameroon. Stool and blood specimens from HIV/AIDS patients and control group were screened respectively for intestinal parasites and for HIV antibodies. Intestinal parasites were identified using direct microscopy, formalin-ether concentration and Ziehl Neelsen methods. Out of 396 participants recruited among patients consulting at hospital, 42 (10.6%) were HIV positive, thirty of them treatment naïve. The overall prevalence of intestinal parasites was 14.64%. Out of 42 HIV/AIDS patients, 59.5% (25/42) were infected with intestinal parasites, while only 9.32% (33/354) of the HIV negative patients were infected with intestinal parasites. The parasites detected in our study population included Crystosporidium parvum (2.53%), Entamoeba histolytica (7.52%), Entamoeba coli (4.04%), Giardia lamblia (0.25%), Trichuris trichura (0.25%), Strongyloides stercoralis (0.25%) and Taenia spp. (0.25%). In the HIV infected group, Crystosporidium parvum (19.04%), Entamoeba histolytica (19.04%), Entamoeba coli (21.42%), Giardia lamblia (2.38%), Strongyloides stercoralis (0.25%) and Taenia spp. (0.25%) were found. Crystosporidium parvum was found to be significantly higher in HIV/AIDS patients than in controls (Pintestinal parasitosis. Routine examinations of stool samples for parasites would significantly benefit the HIV patients by contributing in reducing morbidity and improving the efficiency of antiretroviral treatment. Even after the introduction of free anti-retroviral drugs, opportunistic intestinal infections are still a threat. HIV patients should be screened

  7. [Cloning of VH and VL Gene of Human anti-IL1RAP McAb and Construction of Recombinant Chimeric Receptor].

    Science.gov (United States)

    Yin, Ling-Ling; Ruan, Su-Hong; Tian, Yu; Zhao, Kai; Xu, Kai Lin

    2015-10-01

    To clone the variable region genes of human anti-IL1RAP (IL-1 receptor accessory protein) monoclonal antibodies (McAb) and to construct IL1RAP chimeric antigen receptors (CARs). The VH and VL DNA of IL1RAP single chain antibodies were amplified by RACE and overlap extension PCR from total RNA extracted from 3H6E10 and 10D8A7 hybridoma and ligated into specific IL1RAP single-chain variable fragments (scFv). CD8α transmembrane domain, CD137 intracellular domain, TCR ζ chain, human CD8α signal peptide and scFv-anti-IL1RAP were cloned into plasmid LV-lac. Recombinant lentiviruses were generated by co-transfection of recombinant plasmid LV-lac, pMD2. G, and psPAX2 helper vectors into 293FT packing cells. The VH and VL genes of 2 human anti-IL1RAP McAb were acquired. The 3H6E10 VH and VL genes consisted of 402 bp and 393 bp encoding 134 and 131 aminoacid residues, respectively; 10D8A7 VH and VL genes consisted of 423 bp and 381 bp encoding 141 and 127 amine acid residues, respectively. Recombinant expression vertors LV-3H6E10 scFv-ICD and LV-10D8A7 scFv-ICD (ICD: CD8α transmembrane domain-CD137 intracellular domain-TCR ζ chain) were constructed. The target fragments were demonstrated by sequencing analysis. Recombinant plasmids were transfected into 293FT cells and lentiviral particles were acquired. Human anti-IL1RAP recombinant receptors are constructed successfully and lay a good foundation for the construction of IL1RAP-CAR killer T cell vaccine.

  8. An improved anti-leech mechanism based on session identifier

    Science.gov (United States)

    Zhang, Jianbiao; Zhu, Tong; Zhang, Han; Lin, Li

    2012-01-01

    With the rapid development of information technology and extensive requirement of network resource sharing, plenty of resource hotlinking phenomenons appear on the internet. The hotlinking problem not only harms the interests of legal websites but also leads to a great affection to fair internet environment. The anti-leech technique based on session identifier is highly secure, but the transmission of session identifier in plaintext form causes some security flaws. In this paper, a proxy hotlinking technique based on session identifier is introduced firstly to illustrate these security flaws; next, this paper proposes an improved anti-leech mechanism based on session identifier, the mechanism takes the random factor as the core and detects hotlinking request using a map table that contains random factor, user's information and time stamp; at last the paper analyzes the security of mechanism in theory. The result reveals that the improved mechanism has the merits of simple realization, high security and great flexibility.

  9. Functional expression of parasite drug targets and their human orthologs in yeast.

    Directory of Open Access Journals (Sweden)

    Elizabeth Bilsland

    2011-10-01

    Full Text Available The exacting nutritional requirements and complicated life cycles of parasites mean that they are not always amenable to high-throughput drug screening using automated procedures. Therefore, we have engineered the yeast Saccharomyces cerevisiae to act as a surrogate for expressing anti-parasitic targets from a range of biomedically important pathogens, to facilitate the rapid identification of new therapeutic agents.Using pyrimethamine/dihydrofolate reductase (DHFR as a model parasite drug/drug target system, we explore the potential of engineered yeast strains (expressing DHFR enzymes from Plasmodium falciparum, P. vivax, Homo sapiens, Schistosoma mansoni, Leishmania major, Trypanosoma brucei and T. cruzi to exhibit appropriate differential sensitivity to pyrimethamine. Here, we demonstrate that yeast strains (lacking the major drug efflux pump, Pdr5p expressing yeast ((ScDFR1, human ((HsDHFR, Schistosoma ((SmDHFR, and Trypanosoma ((TbDHFR and (TcDHFR DHFRs are insensitive to pyrimethamine treatment, whereas yeast strains producing Plasmodium ((PfDHFR and (PvDHFR DHFRs are hypersensitive. Reassuringly, yeast strains expressing field-verified, drug-resistant mutants of P. falciparum DHFR ((Pfdhfr(51I,59R,108N are completely insensitive to pyrimethamine, further validating our approach to drug screening. We further show the versatility of the approach by replacing yeast essential genes with other potential drug targets, namely phosphoglycerate kinases (PGKs and N-myristoyl transferases (NMTs.We have generated a number of yeast strains that can be successfully harnessed for the rapid and selective identification of urgently needed anti-parasitic agents.

  10. Gammaherpesvirus Co-infection with Malaria Suppresses Anti-parasitic Humoral Immunity.

    Directory of Open Access Journals (Sweden)

    Caline G Matar

    2015-05-01

    Full Text Available Immunity to non-cerebral severe malaria is estimated to occur within 1-2 infections in areas of endemic transmission for Plasmodium falciparum. Yet, nearly 20% of infected children die annually as a result of severe malaria. Multiple risk factors are postulated to exacerbate malarial disease, one being co-infections with other pathogens. Children living in Sub-Saharan Africa are seropositive for Epstein Barr Virus (EBV by the age of 6 months. This timing overlaps with the waning of protective maternal antibodies and susceptibility to primary Plasmodium infection. However, the impact of acute EBV infection on the generation of anti-malarial immunity is unknown. Using well established mouse models of infection, we show here that acute, but not latent murine gammaherpesvirus 68 (MHV68 infection suppresses the anti-malarial humoral response to a secondary malaria infection. Importantly, this resulted in the transformation of a non-lethal P. yoelii XNL infection into a lethal one; an outcome that is correlated with a defect in the maintenance of germinal center B cells and T follicular helper (Tfh cells in the spleen. Furthermore, we have identified the MHV68 M2 protein as an important virus encoded protein that can: (i suppress anti-MHV68 humoral responses during acute MHV68 infection; and (ii plays a critical role in the observed suppression of anti-malarial humoral responses in the setting of co-infection. Notably, co-infection with an M2-null mutant MHV68 eliminates lethality of P. yoelii XNL. Collectively, our data demonstrates that an acute gammaherpesvirus infection can negatively impact the development of an anti-malarial immune response. This suggests that acute infection with EBV should be investigated as a risk factor for non-cerebral severe malaria in young children living in areas endemic for Plasmodium transmission.

  11. The transport of nifurtimox, an anti-trypanosomal drug, in an in vitro model of the human blood-brain barrier: evidence for involvement of breast cancer resistance protein.

    Science.gov (United States)

    Watson, Christopher P; Dogruel, Murat; Mihoreanu, Larisa; Begley, David J; Weksler, Babette B; Couraud, Pierre O; Romero, Ignacio A; Thomas, Sarah A

    2012-02-03

    Human African trypanosomiasis (HAT) is a parasitic disease affecting sub-Saharan Africa. The parasites are able to traverse the blood-brain barrier (BBB), which marks stage 2 (S2) of the disease. Delivery of anti-parasitic drugs across the BBB is key to treating S2 effectively and the difficulty in achieving this goal is likely to be a reason why some drugs require highly intensive treatment regimes to be effective. This study aimed to investigate not only the drug transport mechanisms utilised by nifurtimox at the BBB, but also the impact of nifurtimox-eflornithine combination therapy (NECT) and other anti-HAT drug combination therapies (CTs) on radiolabelled-nifurtimox delivery in an in vitro model of drug accumulation and the human BBB, the hCMEC/D3 cell line. We found that nifurtimox appeared to use several membrane transporters, in particular breast-cancer resistance protein (BCRP), to exit the BBB cells. The addition of eflornithine caused no change in the accumulation of nifurtimox, nor did the addition of clinically relevant doses of the other anti-HAT drugs suramin, nifurtimox or melarsoprol, but a significant increase was observed with the addition of pentamidine. The results provide evidence that anti-HAT drugs are interacting with membrane transporters at the human BBB and suggest that combination with known transport inhibitors could potentially improve their efficacy. Copyright © 2011 Elsevier B.V. All rights reserved.

  12. Immunodiagnosis of parasitic infections using nuclear techniques

    International Nuclear Information System (INIS)

    1985-07-01

    This report documents the recommendations of the ''Advisory Group on Immunodiagnosis of Parasitic Infections Using Nuclear Techniques'' with a focus on malaria, schistosomiasis and filariasis. Radionuclide tracers are considered an important component of present and future immunological methods for the assessment of the host's humoral and cellular immunity to the parasite and the detection of parasite antigen(s) in human body fluids. The Advisory Group has concluded that there is a continuing need for the development and application of immunodiagnostic methods in parasitic diseases. This report concerns methods which are currently or potentially applicable to immunodiagnostic investigations in parasitic diseases. Reference is made, where appropriate, to recent developments in research which may lead to improvement and standardization of methods now available and the development of new methodology. Separate abstracts on various papers presented were prepared

  13. Drug target identification in protozoan parasites.

    Science.gov (United States)

    Müller, Joachim; Hemphill, Andrew

    2016-08-01

    Despite the fact that diseases caused by protozoan parasites represent serious challenges for public health, animal production and welfare, only a limited panel of drugs has been marketed for clinical applications. Herein, the authors investigate two strategies, namely whole organism screening and target-based drug design. The present pharmacopoeia has resulted from whole organism screening, and the mode of action and targets of selected drugs are discussed. However, the more recent extensive genome sequencing efforts and the development of dry and wet lab genomics and proteomics that allow high-throughput screening of interactions between micromolecules and recombinant proteins has resulted in target-based drug design as the predominant focus in anti-parasitic drug development. Selected examples of target-based drug design studies are presented, and calcium-dependent protein kinases, important drug targets in apicomplexan parasites, are discussed in more detail. Despite the enormous efforts in target-based drug development, this approach has not yet generated market-ready antiprotozoal drugs. However, whole-organism screening approaches, comprising of both in vitro and in vivo investigations, should not be disregarded. The repurposing of already approved and marketed drugs could be a suitable strategy to avoid fastidious approval procedures, especially in the case of neglected or veterinary parasitoses.

  14. Combined Immune Therapy for the Treatment of Visceral Leishmaniasis.

    Directory of Open Access Journals (Sweden)

    Rebecca J Faleiro

    2016-02-01

    Full Text Available Chronic disease caused by infections, cancer or autoimmunity can result in profound immune suppression. Immunoregulatory networks are established to prevent tissue damage caused by inflammation. Although these immune checkpoints preserve tissue function, they allow pathogens and tumors to persist, and even expand. Immune checkpoint blockade has recently been successfully employed to treat cancer. This strategy modulates immunoregulatory mechanisms to allow host immune cells to kill or control tumors. However, the utility of this approach for controlling established infections has not been extensively investigated. Here, we examined the potential of modulating glucocorticoid-induced TNF receptor-related protein (GITR on T cells to improve anti-parasitic immunity in blood and spleen tissue from visceral leishmaniasis (VL patients infected with Leishmania donovani. We found little effect on parasite growth or parasite-specific IFNγ production. However, this treatment reversed the improved anti-parasitic immunity achieved by IL-10 signaling blockade. Further investigations using an experimental VL model caused by infection of C57BL/6 mice with L. donovani revealed that this negative effect was prominent in the liver, dependent on parasite burden and associated with an accumulation of Th1 cells expressing high levels of KLRG-1. Nevertheless, combined anti-IL-10 and anti-GITR mAb treatment could improve anti-parasitic immunity when used with sub-optimal doses of anti-parasitic drug. However, additional studies with VL patient samples indicated that targeting GITR had no overall benefit over IL-10 signaling blockade alone at improving anti-parasitic immune responses, even with drug treatment cover. These findings identify several important factors that influence the effectiveness of immune modulation, including parasite burden, target tissue and the use of anti-parasitic drug. Critically, these results also highlight potential negative effects of

  15. Analysis of nematode motion using an improved light-scatter based system.

    Directory of Open Access Journals (Sweden)

    Chuck S Nutting

    2015-02-01

    Full Text Available The detailed assessment of nematode activity and viability still remains a relatively undeveloped area of biological and medical research. Computer-based approaches to assessing the motility of larger nematode stages have been developed, yet these lack the capability to detect and analyze the more subtle and important characteristics of the motion of nematodes. There is currently a need to improved methods of assessing the viability and health of parasitic worms.We describe here a system that converts the motion of nematodes through a light-scattering system into an electrical waveform, and allows for reproducible, and wholly non-subjective, assessment of alterations in motion, as well as estimation of the number of nematode worms of different forms and sizes. Here we have used Brugia sp. microfilariae (L1, infective larvae (L3 and adults, together with the free-living nematode Caenorhabditis elegans.The motion of worms in a small (200 ul volume can be detected, with the presence of immotile worms not interfering with the readings at practical levels (up to at least 500 L1 /200 ul. Alterations in the frequency of parasite movement following the application of the anti-parasitic drugs, (chloroquine and imatinib; the anti-filarial effect of the latter agent is the first demonstrated here for the first time. This system can also be used to estimate the number of parasites, and shortens the time required to estimate parasites numbers, and eliminates the need for microscopes and trained technicians to provide an estimate of microfilarial sample sizes up to 1000 parasites/ml. Alterations in the form of motion of the worms can also be depicted.This new instrument, named a "WiggleTron", offers exciting opportunities to further study nematode biology and to aid drug discovery, as well as contributing to a rapid estimate of parasite numbers in various biological samples.

  16. Improving Construction Process through Integration and Concurrent Engineering

    Directory of Open Access Journals (Sweden)

    Malik Khalfan

    2012-11-01

    Full Text Available In an increasingly competitive business environment, improvedtime-to-market, reduced production cost, quality of the productand customer involvement are rapidly becoming the key successfactors for any product development process. Consequently, mostorganisations are moving towards the adoption of latest technologyand new management concepts and philosophies such as totalquality management and concurrent engineering (CE to bringimprovement in their product development process. This paperdiscusses the adoption of integrated processes and CE withinthe construction industry to enable construction organisations toimprove their project development process. It also discusses aproposed integrated database model for the construction projects,which should enable the construction process to improve, becomemore effective and more efficient.

  17. Nectar chemistry mediates the behavior of parasitized bees: consequences for plant fitness.

    Science.gov (United States)

    Richardson, Leif L; Bowers, M Deane; Irwin, Rebecca E

    2016-02-01

    Plants produce an array of secondary metabolites that play important ecological roles as anti-herbivore and anti-pathogen defenses. Many herbivores experience physiological costs when they consume secondary metabolites, yet some also benefit, for example when these chemicals confer resistance to parasites and predators. Secondary metabolites are often present in nectar and pollen, which is paradoxical given that floral rewards are important in the attraction of mutualists rather than deterrence of antagonists. Motivated by studies of interactions among plants, herbivores, and parasites, as well as research showing that secondary metabolites can reduce bee disease, we characterized the occurrence of two iridoid glycosides, aucubin and catalpol, in floral rewards and other tissues of the bee pollinated plant, Chelone glabra. We then experimentally investigated effects of nectar iridoid glycoside concentrations on the foraging behavior of bumble bee pollinators naturally afflicted by a parasitoid fly and a protozoan intestinal parasite, and subsequent effects on an estimate of plant reproduction. We found that floral nectar had lower iridoid glycoside concentrations than leaves, pollen, and corollas, and that, compared to those plant parts, the relative ratio of the two primary iridoid glycosides, aucubin and catalpol, was reversed in nectar. Whether bees carried parasitoid fly larvae did not affect their response to nectar chemistry; however, there was a significant interaction between protozoan parasite infection and nectar treatment, with infected bees foraging longer at flowers with high compared to low nectar iridoid glycoside concentrations. Parasitized bees were also more likely to return to inflorescences with high iridoid glycoside nectar. Consequently, flowers in the high iridoid glycoside nectar treatment donated significantly more pollen to conspecific stigmas than did flowers in the low iridoid glycoside treatment, suggesting an increase in male plant

  18. Towards identifying novel anti-Eimeria agents: trace elements, vitamins, and plant-based natural products.

    Science.gov (United States)

    Wunderlich, Frank; Al-Quraishy, Saleh; Steinbrenner, Holger; Sies, Helmut; Dkhil, Mohamed A

    2014-10-01

    Eimeriosis, a widespread infectious disease of livestock, is caused by coccidian protozoans of the genus Eimeria. These obligate intracellular parasites strike the digestive tract of their hosts and give rise to enormous economic losses, particularly in poultry, ruminants including cattle, and rabbit farming. Vaccination, though a rational prophylactic measure, has not yet been as successful as initially thought. Numerous broad-spectrum anti-coccidial drugs are currently in use for treatment and prophylactic control of eimeriosis. However, increasing concerns about parasite resistance, consumer health, and environmental safety of the commercial drugs warrant efforts to search for novel agents with anti-Eimeria activity. This review summarizes current approaches to prevent and treat eimeriosis such as vaccination and commercial drugs, as well as recent attempts to use dietary antioxidants as novel anti-Eimeria agents. In particular, the trace elements selenium and zinc, the vitamins A and E, and natural products extracted from garlic, barberry, pomegranate, sweet wormwood, and other plants are discussed. Several of these novel anti-Eimeria agents exhibit a protective role against oxidative stress that occurs not only in the intestine of Eimeria-infected animals, but also in their non-parasitized tissues, in particular, in the first-pass organ liver. Currently, it appears to be promising to identify safe combinations of low-cost natural products with high anti-Eimeria efficacy for a potential use as feed supplementation in animal farming.

  19. Paternity-parasitism trade-offs: a model and test of host-parasite cooperation in an avian conspecific brood parasite.

    Science.gov (United States)

    Lyon, Bruce E; Hochachka, Wesley M; Eadie, John M

    2002-06-01

    Efforts to evaluate the evolutionary and ecological dynamics of conspecific brood parasitism in birds and other animals have focused on the fitness costs of parasitism to hosts and fitness benefits to parasites. However, it has been speculated recently that, in species with biparental care, host males might cooperate with parasitic females by allowing access to the host nest in exchange for copulations. We develop a cost-benefit model to explore the conditions under which such host-parasite cooperation might occur. When the brood parasite does not have a nest of her own, the only benefit to the host male is siring some of the parasitic eggs (quasi-parasitism). Cooperation with the parasite is favored when the ratio of host male paternity of his own eggs relative to his paternity of parasitic eggs exceeds the cost of parasitism. When the brood parasite has a nest of her own, a host male can gain additional, potentially more important benefits by siring the high-value, low-cost eggs laid by the parasite in her own nest. Under these conditions, host males should be even more likely to accept parasitic eggs in return for copulations with the parasitic female. We tested these predictions for American coots (Fulica americana), a species with a high frequency of conspecific brood parasitism. Multilocus DNA profiling indicated that host males did not sire any of the parasitic eggs laid in host nests, nor did they sire eggs laid by the parasite in her own nest. We used field estimates of the model parameters from a four-year study of coots to predict the minimum levels of paternity required for the costs of parasitism to be offset by the benefits of mating with brood parasites. Observed levels of paternity were significantly lower than those predicted under a variety of assumptions, and we reject the hypothesis that host males cooperated with parasitic females. Our model clarifies the specific costs and benefits that influence host-parasite cooperation and, more generally

  20. Social Parasites

    Science.gov (United States)

    Lopez, Miguel A.; Nguyen, HoangKim T.; Oberholzer, Michael; Hill, Kent L.

    2011-01-01

    Summary of recent advances Protozoan parasites cause tremendous human suffering worldwide, but strategies for therapeutic intervention are limited. Recent studies illustrate that the paradigm of microbes as social organisms can be brought to bear on questions about parasite biology, transmission and pathogenesis. This review discusses recent work demonstrating adaptation of social behaviors by parasitic protozoa that cause African sleeping sickness and malaria. The recognition of social behavior and cell-cell communication as a ubiquitous property of bacteria has transformed our view of microbiology, but protozoan parasites have not generally been considered in this context. Works discussed illustrate the potential for concepts of sociomicrobiology to provide insight into parasite biology and should stimulate new approaches for thinking about parasites and parasite-host interactions. PMID:22020108

  1. Co-ordinated stage-dependent enhancement of Plasmodium falciparum antioxidant enzymes and heat shock protein expression in parasites growing in oxidatively stressed or G6PD-deficient red blood cells

    Directory of Open Access Journals (Sweden)

    Müller Sylke

    2009-05-01

    Full Text Available Abstract Background Plasmodium falciparum-parasitized red blood cells (RBCs are equipped with protective antioxidant enzymes and heat shock proteins (HSPs. The latter are only considered to protect against thermal stress. Important issues are poorly explored: first, it is insufficiently known how both systems are expressed in relation to the parasite developmental stage; secondly, it is unknown whether P. falciparum HSPs are redox-responsive, in view of redox sensitivity of HSP in eukaryotic cells; thirdly, it is poorly known how the antioxidant defense machinery would respond to increased oxidative stress or inhibited antioxidant defense. Those issues are interesting as several antimalarials increase the oxidative stress or block antioxidant defense in the parasitized RBC. In addition, numerous inhibitors of HSPs are currently developed for cancer therapy and might be tested as anti-malarials. Thus, the joint disruption of the parasite antioxidant enzymes/HSP system would interfere with parasite growth and open new perspectives for anti-malaria therapy. Methods Stage-dependent mRNA expression of ten representative P. falciparum antioxidant enzymes and hsp60/70–2/70–3/75/90 was studied by quantitative real-time RT-PCR in parasites growing in normal RBCs, in RBCs oxidatively-stressed by moderate H2O2 generation and in G6PD-deficient RBCs. Protein expression of antioxidant enzymes was assayed by Western blotting. The pentosephosphate-pathway flux was measured in isolated parasites after Sendai-virus lysis of RBC membrane. Results In parasites growing in normal RBCs, mRNA expression of antioxidant enzymes and HSPs displayed co-ordinated stage-dependent modulation, being low at ring, highest at early trophozoite and again very low at schizont stage. Additional exogenous oxidative stress or growth in antioxidant blunted G6PD-deficient RBCs indicated remarkable flexibility of both systems, manifested by enhanced, co-ordinated mRNA expression of

  2. Co-ordinated stage-dependent enhancement of Plasmodium falciparum antioxidant enzymes and heat shock protein expression in parasites growing in oxidatively stressed or G6PD-deficient red blood cells.

    Science.gov (United States)

    Akide-Ndunge, Oscar Bate; Tambini, Elisa; Giribaldi, Giuliana; McMillan, Paul J; Müller, Sylke; Arese, Paolo; Turrini, Francesco

    2009-05-29

    Plasmodium falciparum-parasitized red blood cells (RBCs) are equipped with protective antioxidant enzymes and heat shock proteins (HSPs). The latter are only considered to protect against thermal stress. Important issues are poorly explored: first, it is insufficiently known how both systems are expressed in relation to the parasite developmental stage; secondly, it is unknown whether P. falciparum HSPs are redox-responsive, in view of redox sensitivity of HSP in eukaryotic cells; thirdly, it is poorly known how the antioxidant defense machinery would respond to increased oxidative stress or inhibited antioxidant defense. Those issues are interesting as several antimalarials increase the oxidative stress or block antioxidant defense in the parasitized RBC. In addition, numerous inhibitors of HSPs are currently developed for cancer therapy and might be tested as anti-malarials. Thus, the joint disruption of the parasite antioxidant enzymes/HSP system would interfere with parasite growth and open new perspectives for anti-malaria therapy. Stage-dependent mRNA expression of ten representative P. falciparum antioxidant enzymes and hsp60/70-2/70-3/75/90 was studied by quantitative real-time RT-PCR in parasites growing in normal RBCs, in RBCs oxidatively-stressed by moderate H2O2 generation and in G6PD-deficient RBCs. Protein expression of antioxidant enzymes was assayed by Western blotting. The pentosephosphate-pathway flux was measured in isolated parasites after Sendai-virus lysis of RBC membrane. In parasites growing in normal RBCs, mRNA expression of antioxidant enzymes and HSPs displayed co-ordinated stage-dependent modulation, being low at ring, highest at early trophozoite and again very low at schizont stage. Additional exogenous oxidative stress or growth in antioxidant blunted G6PD-deficient RBCs indicated remarkable flexibility of both systems, manifested by enhanced, co-ordinated mRNA expression of antioxidant enzymes and HSPs. Protein expression of

  3. Acetate formation in the energy metabolism of parasitic helminths and protists.

    Science.gov (United States)

    Tielens, Aloysius G M; van Grinsven, Koen W A; Henze, Katrin; van Hellemond, Jaap J; Martin, William

    2010-03-15

    Formation and excretion of acetate as a metabolic end product of energy metabolism occurs in many protist and helminth parasites, such as the parasitic helminths Fasciola hepatica, Haemonchus contortus and Ascaris suum, and the protist parasites, Giardia lamblia, Entamoeba histolytica, Trichomonas vaginalis as well as Trypanosoma and Leishmania spp. In all of these parasites acetate is a main end product of their energy metabolism, whereas acetate formation does not occur in their mammalian hosts. Acetate production might therefore harbour novel targets for the development of new anti-parasitic drugs. In parasites, acetate is produced from acetyl-CoA by two different reactions, both involving substrate level phosphorylation, that are catalysed by either a cytosolic acetyl-CoA synthetase (ACS) or an organellar acetate:succinate CoA-transferase (ASCT). The ACS reaction is directly coupled to ATP synthesis, whereas the ASCT reaction yields succinyl-CoA for ATP formation via succinyl-CoA synthetase (SCS). Based on recent work on the ASCTs of F. hepatica, T. vaginalis and Trypanosoma brucei we suggest the existence of three subfamilies of enzymes within the CoA-transferase family I. Enzymes of these three subfamilies catalyse the ASCT reaction in eukaryotes via the same mechanism, but the subfamilies share little sequence homology. The CoA-transferases of the three subfamilies are all present inside ATP-producing organelles of parasites, those of subfamily IA in the mitochondria of trypanosomatids, subfamily IB in the mitochondria of parasitic worms and subfamily IC in hydrogenosome-bearing parasites. Together with the recent characterisation among non-parasitic protists of yet a third route of acetate formation involving acetate kinase (ACK) and phosphotransacetylase (PTA) that was previously unknown among eukaryotes, these recent developments provide a good opportunity to have a closer look at eukaryotic acetate formation. (c) 2010 Australian Society for Parasitology

  4. Improved superposition schemes for approximate multi-caloron configurations

    International Nuclear Information System (INIS)

    Gerhold, P.; Ilgenfritz, E.-M.; Mueller-Preussker, M.

    2007-01-01

    Two improved superposition schemes for the construction of approximate multi-caloron-anti-caloron configurations, using exact single (anti-)caloron gauge fields as underlying building blocks, are introduced in this paper. The first improvement deals with possible monopole-Dirac string interactions between different calorons with non-trivial holonomy. The second one, based on the ADHM formalism, improves the (anti-)selfduality in the case of small caloron separations. It conforms with Shuryak's well-known ratio-ansatz when applied to instantons. Both superposition techniques provide a higher degree of (anti-)selfduality than the widely used sum-ansatz, which simply adds the (anti)caloron vector potentials in an appropriate gauge. Furthermore, the improved configurations (when discretized onto a lattice) are characterized by a higher stability when they are exposed to lattice cooling techniques

  5. Trans-specific gene silencing of acetyl-CoA carboxylase in a root-parasitic plant.

    Science.gov (United States)

    Bandaranayake, Pradeepa C G; Yoder, John I

    2013-05-01

    Parasitic species of the family Orobanchaceae are devastating agricultural pests in many parts of the world. The control of weedy Orobanchaceae spp. is challenging, particularly due to the highly coordinated life cycles of the parasite and host plants. Although host genetic resistance often provides the foundation of plant pathogen management, few genes that confer resistance to root parasites have been identified and incorporated into crop species. Members of the family Orobanchaceae acquire water, nutrients, macromolecules, and oligonucleotides from host plants through haustoria that connect parasite and host plant roots. We are evaluating a resistance strategy based on using interfering RNA (RNAi) that is made in the host but inhibitory in the parasite as a parasite-derived oligonucleotide toxin. Sequences from the cytosolic acetyl-CoA carboxylase (ACCase) gene from Triphysaria versicolor were cloned in hairpin conformation and introduced into Medicago truncatula roots by Agrobacterium rhizogenes transformation. Transgenic roots were recovered for four of five ACCase constructions and infected with T. versicolor against parasitic weeds. In all cases, Triphysaria root viability was reduced up to 80% when parasitizing a host root bearing the hairpin ACCase. Triphysaria root growth was recovered by exogenous application of malonate. Reverse-transcriptase polymerase chain reaction (RT-PCR) showed that ACCase transcript levels were dramatically decreased in Triphysaria spp. parasitizing transgenic Medicago roots. Northern blot analysis identified a 21-nucleotide, ACCase-specific RNA in transgenic M. truncatula and in T. versicolor attached to them. One hairpin ACCase construction was lethal to Medicago spp. unless grown in media supplemented with malonate. Quantitative RT-PCR showed that the Medicago ACCase was inhibited by the Triphysaria ACCase RNAi. This work shows that ACCase is an effective target for inactivation in parasitic plants by trans-specific gene

  6. Sequence mining and transcript profiling to explore cyst nematode parasitism

    Directory of Open Access Journals (Sweden)

    Recknor Justin

    2009-01-01

    currently known 6,860 H. glycines genes to a pool of 788 most promising candidate genes (including known parasitism genes and documented their expression profiles. Using our approach to pre-select genes likely involved in parasitism now allows detailed functional analyses in a manner not feasible for larger numbers of genes. The generation of the candidate pool described here is an important enabling advance because it will significantly facilitate the unraveling of fascinating plant-animal interactions and deliver knowledge that can be transferred to other pathogen-host systems. Ultimately, the exploration of true parasitism genes verified from the gene pool delineated here will identify weaknesses in the nematode life cycle that can be exploited by novel anti-nematode efforts.

  7. Cysteine Protease Inhibitors as Chemotherapy: Lessons from a Parasite Target

    Science.gov (United States)

    Selzer, Paul M.; Pingel, Sabine; Hsieh, Ivy; Ugele, Bernhard; Chan, Victor J.; Engel, Juan C.; Bogyo, Matthew; Russell, David G.; Sakanari, Judy A.; McKerrow, James H.

    1999-09-01

    Papain family cysteine proteases are key factors in the pathogenesis of cancer invasion, arthritis, osteoporosis, and microbial infections. Targeting this enzyme family is therefore one strategy in the development of new chemotherapy for a number of diseases. Little is known, however, about the efficacy, selectivity, and safety of cysteine protease inhibitors in cell culture or in vivo. We now report that specific cysteine protease inhibitors kill Leishmania parasites in vitro, at concentrations that do not overtly affect mammalian host cells. Inhibition of Leishmania cysteine protease activity was accompanied by defects in the parasite's lysosome/endosome compartment resembling those seen in lysosomal storage diseases. Colocalization of anti-protease antibodies with biotinylated surface proteins and accumulation of undigested debris and protease in the flagellar pocket of treated parasites were consistent with a pathway of protease trafficking from flagellar pocket to the lysosome/endosome compartment. The inhibitors were sufficiently absorbed and stable in vivo to ameliorate the pathology associated with a mouse model of Leishmania infection.

  8. Noise Depression of Parasitic Capacitance for Frequency Detection of Micromechanical Bulk Disk Resonator

    DEFF Research Database (Denmark)

    Tang, Meng; Cagliani, Alberto; Escouflaire, Marie

    2010-01-01

    the frequency noise of the system. A capacitor cancellation circuit is used to subtract the parasitic capacitor. Measurements are conducted before and after the cancellation, and results show that after cancellation, the anti resonance is suppressed and the frequency noise is decreased, thus decreasing...

  9. Intestinal parasitic infections in HIV infected and non-infected patients in a low HIV prevalence region, West-Cameroon.

    Directory of Open Access Journals (Sweden)

    Céline Nguefeu Nkenfou

    Full Text Available The magnitude of intestinal parasitic infection in acquired immunodeficiency syndrome patients requires careful consideration in the developing world where poor nutrition is associated with poor hygiene and several tropical diseases. However, there have been very few studies addressing this issue in Cameroon. This study was conducted to determine the prevalence of intestinal parasitosis in HIV/AIDS patients in Dschang -Cameroon. Stool and blood specimens from HIV/AIDS patients and control group were screened respectively for intestinal parasites and for HIV antibodies. Intestinal parasites were identified using direct microscopy, formalin-ether concentration and Ziehl Neelsen methods. Out of 396 participants recruited among patients consulting at hospital, 42 (10.6% were HIV positive, thirty of them treatment naïve. The overall prevalence of intestinal parasites was 14.64%. Out of 42 HIV/AIDS patients, 59.5% (25/42 were infected with intestinal parasites, while only 9.32% (33/354 of the HIV negative patients were infected with intestinal parasites. The parasites detected in our study population included Crystosporidium parvum (2.53%, Entamoeba histolytica (7.52%, Entamoeba coli (4.04%, Giardia lamblia (0.25%, Trichuris trichura (0.25%, Strongyloides stercoralis (0.25% and Taenia spp. (0.25%. In the HIV infected group, Crystosporidium parvum (19.04%, Entamoeba histolytica (19.04%, Entamoeba coli (21.42%, Giardia lamblia (2.38%, Strongyloides stercoralis (0.25% and Taenia spp. (0.25% were found. Crystosporidium parvum was found to be significantly higher in HIV/AIDS patients than in controls (P<0.05. Multivariate analysis showed that the HIV status and the quality of water were the major risk factors for intestinal parasitosis. Routine examinations of stool samples for parasites would significantly benefit the HIV patients by contributing in reducing morbidity and improving the efficiency of antiretroviral treatment. Even after the introduction

  10. Inhibitory effect of apicidin on in vitro and in vivo growth of Babesia parasites

    OpenAIRE

    Munkhjargal, T; Aboulaila, M.R.A; Sivakumar, T; Yokoyama, Naoaki; Igarashi, Ikuo

    2009-01-01

    Apicidin, a histone deacetylase inhibitor, has a broad spectrum of anti-protozoal activities against apicomplexan parasites. In the present study, we evaluated the inhibitory effect of apicidin on the asexual growth of bovine Babesia parasites (B. bovis and B. bigemina) in vitro, as well as on the in vivo growth of B. microti in mice. The growth of B. bovis and B. bigemina was significantly inhibited in the presence of 3 ng/ml apicidin. Complete inhibition of B. bovis and B. bigemina growth w...

  11. Immune response to Taenia solium cysticerci after anti-parasitic therapy.

    Science.gov (United States)

    Singh, Aloukick K; Singh, Satyendra K; Singh, Amrita; Gupta, Kamlesh K; Khatoon, Jahanarah; Prasad, Amit; Rai, Ravi P; Gupta, Rakesh K; Tripathi, Mukesh; Husain, Nuzhat; Prasad, Kashi N

    2015-10-01

    Albendazole is the drug of choice for Taenia solium infection. Concomitant administration of steroid has been advocated to avoid adverse reactions to albendazole therapy in neurocysticercosis. Some T. solium cysticerci (larvae) respond to albendazole therapy while others do not and the reasons remain unexplained. We hypothesise that the immune response differs between treatment responder and non-responder cysticerci and this may determine the outcome. Twenty swine naturally infected with T. solium were purchased from the market and the infection was confirmed by magnetic resonance imaging. Swine were divided into two groups; swine in group 1 were treated with albendazole and those in group 2 were treated with albendazole plus steroid (prednisolone). All the animals underwent follow-up MRIs at 6 and 12 weeks after start of therapy and were then sacrificed. Tissues surrounding the cysticerci were collected and studied for the expression of different cytokines by reverse transcriptase PCR and ELISA. Albendazole therapy was found to be more effective in parasite killing than albendazole plus steroid (94.11% versus 70.96%, P=0.011). Albendazole therapy provoked a pro-inflammatory, Th1 (IFN-γ) and pleiotropic (IL-6) cytokine response around the dead cysticerci. Despite a heavy parasite burden in the brain, all the pigs treated with albendazole plus steroid survived. In this group of animals, a mixed pro-inflammatory Th1, Th2 (IL-4) and regulatory cytokine (IL-10) response was associated with responder cysticerci. Further, Th2 and regulatory cytokine responses were associated with non-responder cysticerci. Copyright © 2015 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

  12. Construction and Characterization of a Humanized Anti-Epstein-Barr Virus gp350 Antibody with Neutralizing Activity in Cell Culture

    Directory of Open Access Journals (Sweden)

    Jerome E. Tanner

    2018-04-01

    Full Text Available Acute Epstein-Barr virus (EBV infection in immunosuppressed transplant patients can give rise to a malignant B-cell proliferation known as post-transplant lymphoproliferative disease (PTLD. The EBV major virion surface glycoprotein (gp350 is a principal target of naturally occurring neutralizing antibodies and is viewed as the best target to prevent acute infection and PTLD in at-risk transplant recipients. We have constructed a humanized (hu version of the murine anti-gp350 neutralizing monoclonal antibody 72a1. The hu72a1 IgG1 antibody displayed no significant anti-mouse activity, recognized both gp350 and its splice variant gp220 as well as a gp350 peptide that was shown to constitute the principal EBV gp350 neutralizing epitope when tested in immunoassays. Hu72a1 antibody blocked in vitro EBV infection of B cells at a level which equaled that of a mouse-human chimeric 72a1 antibody construct. This work provides a further structural and immunological understanding of the 72a1 antibody interaction with EBV gp350, and constitutes a launch point for future anti-EBV therapeutic antibodies designed to block EBV infection and prevent PTLD while eliminating the deleterious antigenic murine features of the original 72a1 antibody.

  13. A PKA survival pathway inhibited by DPT-PKI, a new specific cell permeable PKA inhibitor, is induced by T. annulata in parasitized B-lymphocytes.

    Science.gov (United States)

    Guergnon, Julien; Dessauge, Frederic; Traincard, François; Cayla, Xavier; Rebollo, Angelita; Bost, Pierre Etienne; Langsley, Gordon; Garcia, Alphonse

    2006-08-01

    T. annulata, an intracellular pathogenic parasite of the Aplicomplexa protozoan family infects bovine B-lymphocytes and macrophages. Parasitized cells that become transformed survive and proliferate independently of exogenous growth factors. In the present study, we used the isogenic non parasitized BL3 and parasitized TBL3 B cell lines, as a model to evaluate the contribution of two-major PI3-K- and PKA-dependent anti-apoptotic pathways in the survival of T. annulata parasitized B lymphocytes. We found that T. annulata increases PKA activity, induces over-expression of the catalytic subunit and down-regulates the pro-survival phosphorylation state of Akt/PKB. Consistent with a role of PKA activation in survival, two pharmacological inhibitors H89 and KT5720 ablate PKA-dependent survival of parasitized cells. To specifically inhibit PKA pro-survival pathways we linked the DPTsh1 peptide shuttle sequence to PKI(5-24) and we generated DPT-PKI, a cell permeable PKI. DPT-PKI specifically inhibited PKA activity in bovine cell extracts and, as expected, also inhibited the PKA-dependent survival of T. annulata parasitized TBL3 cells. Thus, parasite-dependent constitutive activation of PKA in TBL3 cells generates an anti-apoptotic pathway that can protect T. annulata-infected B cells from apoptosis. These results also indicate that DPT-PKI could be a powerful tool to inhibit PKA pathways in other cell types.

  14. Impacts of parasite infection on columnaris disease of tilapia

    Science.gov (United States)

    There is no information available on whether parasite infection will increase the susceptibility of tilapia to Flavobacterium columnare and whether parasite treatment could improve fish survival after F. columnare exposure. Two trials were conducted to evaluate 1) the susceptibility of hybrid tilapi...

  15. Improved consistency in dosing anti-tuberculosis drugs in Taipei, Taiwan.

    Science.gov (United States)

    Chiang, Chen-Yuan; Yu, Ming-Chih; Shih, Hsiu-Chen; Yen, Muh-Yong; Hsu, Yu-Ling; Yang, Shiang-Lin; Lin, Tao-Ping; Bai, Kuan-Jen

    2012-01-01

    It was reported that 35.5% of tuberculosis (TB) cases reported in 2003 in Taipei City had no recorded pre-treatment body weight and that among those who had, inconsistent dosing of anti-TB drugs was frequent. Taiwan Centers for Disease Control (CDC) have taken actions to strengthen dosing of anti-TB drugs among general practitioners. Prescribing practices of anti-TB drugs in Taipei City in 2007-2010 were investigated to assess whether interventions on dosing were effective. Lists of all notified culture positive TB cases in 2007-2010 were obtained from National TB Registry at Taiwan CDC. A medical audit of TB case management files was performed to collect pretreatment body weight and regimens prescribed at commencement of treatment. Dosages prescribed were compared with dosages recommended. The proportion of patients with recorded pre-treatment body weight was 64.5% in 2003, which increased to 96.5% in 2007-2010 (pTaipei City has remarkably improved after health authorities implemented a series of interventions.

  16. Essential multimeric enzymes in kinetoplastid parasites: A host of potentially druggable protein-protein interactions.

    Science.gov (United States)

    Wachsmuth, Leah M; Johnson, Meredith G; Gavenonis, Jason

    2017-06-01

    Parasitic diseases caused by kinetoplastid parasites of the genera Trypanosoma and Leishmania are an urgent public health crisis in the developing world. These closely related species possess a number of multimeric enzymes in highly conserved pathways involved in vital functions, such as redox homeostasis and nucleotide synthesis. Computational alanine scanning of these protein-protein interfaces has revealed a host of potentially ligandable sites on several established and emerging anti-parasitic drug targets. Analysis of interfaces with multiple clustered hotspots has suggested several potentially inhibitable protein-protein interactions that may have been overlooked by previous large-scale analyses focusing solely on secondary structure. These protein-protein interactions provide a promising lead for the development of new peptide and macrocycle inhibitors of these enzymes.

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

    Directory of Open Access Journals (Sweden)

    Thibault Allain

    2018-02-01

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

  18. [Construction of the lentiviral expression vector for anti-p185(erbB2) mouse/human chimeric antibody].

    Science.gov (United States)

    Liu, Fang; Li, Li; Zhang, Wei; Wang, Qi

    2013-04-01

    This research was to construct the lentiviral expression vector for anti- p185(erbB2) mouse/human chimeric antibody and to determine the expression of the chimeric antibody gene in 293T cells transfected with this vector. The genes (vL and vH) coding light and heavy chain of variable regions of anti-p185(erbB2) mAb and the constant regions of human IgG1 (kappa and gamma1) were cloned with PCR method. The target genes were assembled by three-primers PCR method to obtain the chimeric light chain (L) and the chimeric heavy chain (H). Both chains inserted into the down stream and upper stream of IRES gene of the plasmid pVAX1/IRES respectively. We digested the plasmid pVAX1/ H-IRES-L with endoenzyme and subcloned H-IRES-L into the lentiviral vector pWPI. The enzyme digestion and sequence analysis showed that the lentiviral expression vector pWPI/H-IRES-L was constructed correctly. Then, it was transfected into 293T cells and after 48h, GFP protein expression in 293T cells were detected by fluorescent microscope and the chimeric antibody expression was detected by RT-PCR and direct ELISA. The results showed that after 293T cells were transfected with recombination plasmid, both light and heavy chains of the chimeric antibody genes could express together. The chimeric antibody expressed could bind to p185(erbB2) specifically. This research may lay a sound foundation for further study of anti-p185(erbB2) engineered antibody.

  19. APPLICATION OF BIOTECHNOLOGY TO THE STUDY OF FILARIAL PARASITES AND THEIR VECTORS

    Directory of Open Access Journals (Sweden)

    A. C. Vickery

    2012-09-01

    Full Text Available Over 200 species of filarial parasites have been described, although the life cycle and nature of their obligate intermediate arthropod vectors have been identified for only about a quarter of them. Traditional methods of studying phylogenetic relationships between closely related parasite species have utilized morphologic, biochemical and biologic characteristics, usually of the microfilarial stage. Identification of competent vectors from among complexes of sibling species, has employed similar techniques, despite the fact that differences between geographical isolates may reflect environmental rather than genetically controlled factors. Studies of the prevalence and transmission of animal, human and zoonotic filarids, so important for vector identification and control, has lead to the examination of filarial parasites at the genetic level. Genomic DNA libraries are being constructed and screened for clones which are species specific. From this work, DNA probes which can accurately enumerate larval stages in vector squash preparations, and monoclonal antibodies specific for defined filarial antigens, are being prepared. The nucleotide sequences of rRNA are also being defined. The application of these technologies to the study of filarial parasites and their vectors, promises to not only allow the construction of accurate phylogenetic trees, but also to provide the data necessary for the identification and control of the vectors of filarial pathogens of animals and man.

  20. Can the behaviour of threespine stickleback parasitized with Schistocephalus solidus be replicated by manipulating host physiology?

    Science.gov (United States)

    Grécias, Lucie; Hébert, François Olivier; Berger, Chloé Suzanne; Barber, Iain; Aubin-Horth, Nadia

    2017-01-15

    Sticklebacks infected by the parasitic flatworm Schistocephalus solidus show dramatic changes in phenotype, including a loss of species-typical behavioural responses to predators. The timing of host behaviour change coincides with the development of infectivity of the parasite to the final host (a piscivorous bird), making it an ideal model for studying the mechanisms of infection-induced behavioural modification. However, whether the loss of host anti-predator behaviour results from direct manipulation by the parasite, or is a by-product (e.g. host immune response) or side effect of infection (e.g. energetic loss), remains controversial. To understand the physiological mechanisms that generate these behavioural changes, we quantified the behavioural profiles of experimentally infected fish and attempted to replicate these in non-parasitized fish by exposing them to treatments including immunity activation and fasting, or by pharmacologically inhibiting the stress axis. All fish were screened for the following behaviours: activity, water depth preference, sociability, phototaxis, anti-predator response and latency to feed. We were able to change individual behaviours with certain treatments. Our results suggest that the impact of S. solidus on the stickleback might be of a multifactorial nature. The behaviour changes observed in infected fish might result from the combined effects of modifying the serotonergic axis, lack of energy and activation of the immune system. © 2017. Published by The Company of Biologists Ltd.

  1. Flow cytometric readout based on Mitotracker Red CMXRos staining of live asexual blood stage malarial parasites reliably assesses antibody dependent cellular inhibition

    DEFF Research Database (Denmark)

    Jogdand, Prajakta S; Singh, Susheel K; Christiansen, Michael

    2012-01-01

    asynchronous and tightly synchronized asexual blood stage cultures of Plasmodium falciparum were stained with CMXRos and subjected to detection by flow cytometry and fluorescence microscopy. The parasite counts obtained by flow cytometry were compared to standard microscopic counts obtained through examination......ABSTRACT: BACKGROUND: Functional in vitro assays could provide insights into the efficacy of malaria vaccine candidates. For estimating the anti-parasite effect induced by a vaccine candidate, an accurate determination of live parasite count is an essential component of most in vitro bioassays....... Although traditionally parasites are counted microscopically, a faster, more accurate and less subjective method for counting parasites is desirable. In this study mitochondrial dye (Mitotracker Red CMXRos) was used for obtaining reliable live parasite counts through flow cytometry. METHODS: Both...

  2. Anti-Transgender Prejudice: A Structural Equation Model of Associated Constructs

    Science.gov (United States)

    Tebbe, Esther N.; Moradi, Bonnie

    2012-01-01

    This study aimed to identify theoretically relevant key correlates of anti-transgender prejudice. Specifically, structural equation modeling was used to test the unique relations of anti-lesbian, gay, and bisexual (LGB) prejudice; traditional gender role attitudes; need for closure; and social dominance orientation with anti-transgender prejudice.…

  3. An Inventory of the Plants Used for Parasitic Ailments of Animals

    Directory of Open Access Journals (Sweden)

    Wasim Babar, Zafar Iqbal*, Muhammad Nisar Khan and Ghulam Muhammad

    2012-05-01

    Full Text Available This study was conducted to document the botanicals used for major parasitic ailments of animals in Bhakkar District of Pakistan. Rapid Rural Appraisal was carried out to identify the key respondents (n=115 including local healers, quacks, herders and farmers for the present study. Information was collected using a pre-designed questionnaire and verified through focused group discussions through participatory rural appraisal technique. Gastrointestinal parasites were the most frequently (n=105/115; 91% reported problem of livestock followed by tick infestation (n=91/115; 79% and myiasis (n=84/115; 73%. A total of 69 prescriptions based on 30 plants including 32 for GI parasites, 16 for tick infestation and 21 for myiasis were documented. There were some plants which were reported to be used with a different dose, method of preparation and/or vehicle within the same or a different parasitic condition. Leaves, seeds and/or seed oil and fruit were the most commonly used parts of the plants. The plant materials were given orally in crude form as powder, oil and decoction, and topical application as powder, sprinkling, bath, washing and paste. Plants documented in the present study were new to the area but have already been reported elsewhere for different ailments of animals. Majority of the plants, however, need to be evaluated using standard parasitological procedures to validate their use as anti-parasitics.

  4. Major Reduction in Anti-Malarial Drug Consumption in Senegal after Nation-Wide Introduction of Malaria Rapid Diagnostic Tests

    Science.gov (United States)

    Thiam, Sylla; Thior, Moussa; Faye, Babacar; Ndiop, Médoune; Diouf, Mamadou Lamine; Diouf, Mame Birame; Diallo, Ibrahima; Fall, Fatou Ba; Ndiaye, Jean Louis; Albertini, Audrey; Lee, Evan; Jorgensen, Pernille; Gaye, Oumar; Bell, David

    2011-01-01

    Background While WHO recently recommended universal parasitological confirmation of suspected malaria prior to treatment, debate has continued as to whether wide-scale use of rapid diagnostic tests (RDTs) can achieve this goal. Adherence of health service personnel to RDT results has been poor in some settings, with little impact on anti-malarial drug consumption. The Senegal national malaria control programme introduced universal parasite-based diagnosis using malaria RDTs from late 2007 in all public health facilities. This paper assesses the impact of this programme on anti-malarial drug consumption and disease reporting. Methods and Findings Nationally-collated programme data from 2007 to 2009 including malaria diagnostic outcomes, prescription of artemisinin-based combination therapy (ACT) and consumption of RDTs in public health facilities, were reviewed and compared. Against a marked seasonal variation in all-cause out-patient visits, non-malarial fever and confirmed malaria, parasite-based diagnosis increased nationally from 3.9% of reported malaria-like febrile illness to 86.0% over a 3 year period. The prescription of ACT dropped throughout this period from 72.9% of malaria-like febrile illness to 31.5%, reaching close equivalence to confirmed malaria (29.9% of 584873 suspect fever cases). An estimated 516576 courses of inappropriate ACT prescription were averted. Conclusions The data indicate high adherence of anti-malarial prescribing practice to RDT results after an initial run-in period. The large reduction in ACT consumption enabled by the move from symptom-based to parasite-based diagnosis demonstrates that effective roll-out and use of malaria RDTs is achievable on a national scale through well planned and structured implementation. While more detailed information on management of parasite-negative cases is required at point of care level to assess overall cost-benefits to the health sector, considerable cost-savings were achieved in ACT

  5. Antibodies against the Plasmodium falciparum glutamate-rich protein from naturally exposed individuals living in a Brazilian malaria-endemic area can inhibit in vitro parasite growth

    DEFF Research Database (Denmark)

    Pratt-Riccio, Lilian Rose; Bianco, Cesare; Totino, Paulo Renato Rivas

    2011-01-01

    The glutamate-rich protein (GLURP) is an exoantigen expressed in all stages of the Plasmodium falciparum life cycle in humans. Anti-GLURP antibodies can inhibit parasite growth in the presence of monocytes via antibody-dependent cellular inhibition (ADCI), and a major parasite-inhibitory region h...

  6. Using rapid diagnostic tests as source of malaria parasite DNA for molecular analyses in the era of declining malaria prevalence

    DEFF Research Database (Denmark)

    Ishengoma, Deus S; Lwitiho, Sudi; Madebe, Rashid A

    2011-01-01

    was conducted to examine if sufficient DNA could be successfully extracted from malaria rapid diagnostic tests (RDTs), used and collected as part of routine case management services in health facilities, and thus forming the basis for molecular analyses, surveillance and quality control (QC) testing of RDTs....... continued molecular surveillance of malaria parasites is important to early identify emerging anti-malarial drug resistance, it is becoming increasingly difficult to obtain parasite samples from ongoing studies, such as routine drug efficacy trials. To explore other sources of parasite DNA, this study...

  7. Determining intestinal parasitic infections (IPIs) in inmates from Kajang Prison, Selangor, Malaysia for improved prison management.

    Science.gov (United States)

    Angal, Lorainne; Mahmud, Rohela; Samin, Sajideh; Yap, Nan-Jiun; Ngui, Romano; Amir, Amirah; Ithoi, Init; Kamarulzaman, Adeeba; Lim, Yvonne A L

    2015-10-29

    The prison management in Malaysia is proactively seeking to improve the health status of the prison inmates. Intestinal parasitic infections (IPIs) are widely distributed throughout the world and are still gaining great concern due to their significant morbidity and mortality among infected humans. In Malaysia, there is a paucity of information on IPIs among prison inmates. In order to further enhance the current health strategies employed, the present study aims to establish firm data on the prevalence and diversity of IPIs among HIV-infected and non-HIV-infected individuals in a prison, an area in which informed knowledge is still very limited. Samples were subjected to microscopy examination and serological test (only for Strongyloides). Speciation for parasites on microscopy-positive samples and seropositive samples for Strongyloides were further determined via polymerase chain reaction. SPSS was used for statistical analysis. A total of 294 stool and blood samples each were successfully collected, involving 131 HIV positive and 163 HIV negative adult male inmates whose age ranged from 21 to 69-years-old. Overall prevalence showed 26.5% was positive for various IPIs. The IPIs detected included Blastocystis sp., Strongyloides stercoralis, Entamoeba spp., Cryptosporidium spp., Giardia spp., and Trichuris trichiura. Comparatively, the rate of IPIs was slightly higher among the HIV positive inmates (27.5%) than HIV negative inmates (25.8%). Interestingly, seropositivity for S. stercoralis was more predominant in HIV negative inmates (10.4%) compared to HIV-infected inmates (6.9%), however these findings were not statistically significant. Polymerase chain reaction (PCR) confirmed the presence of Blastocystis, Strongyloides, Entamoeba histolytica and E. dispar. These data will enable the health care providers and prison management staff to understand the trend and epidemiological situations in HIV/parasitic co-infections in a prison. This information will further

  8. In vitro and in vivo anti-malarial activity of Boerhavia elegans and Solanum surattense

    Directory of Open Access Journals (Sweden)

    Khodakarim Nastaran

    2010-05-01

    Full Text Available Abstract Background There is an urgent need to identify new anti-malarial drug targets for both prophylaxis and chemotherapy, due to the increasing problem of drug resistance to malaria parasites. In the present study, the aim was to discover novel, effective plant-based extracts for the activity against malaria. Methods Ten plants found in Iran were selected by ethnobotanical survey of medicinal plants. The crude ethanolic extracts were tested for in vitro anti-plasmodial activity against two strains of Plasmodium falciparum: K1 (chloroquine-resistant strain and CY27 (chloroquine-sensitive strain, using the parasite lactate dehydrogenase (pLDH assay. The anti-plasmodial activity of the extracts was also assessed in the 4-day suppressive anti-malarial assay in mice inoculated with Plasmodium berghei (ANKA strain. Crude ethanolic extracts showed good anti-plasmodial activity were further fractionated by partitioning in water and dichloromethane. Results Of 10 plant species assayed, three species: Boerhavia elegans (Choisy, Solanum surattense (Burm.f. and Prosopis juliflora (Sw. showed promising anti-plasmodial activity in vitro (IC50 ≤ 50 μg/ml and in vivo with no toxicity. The dichloromethane fraction of three extracts revealed stronger anti-plasmodial activity than the total extracts. Conclusion Anti-plasmodial activities of extracts of B. elegans and S. surattense are reported for the first time.

  9. In vitro and in vivo anti-malarial activity of Boerhavia elegans and Solanum surattense

    Science.gov (United States)

    2010-01-01

    Background There is an urgent need to identify new anti-malarial drug targets for both prophylaxis and chemotherapy, due to the increasing problem of drug resistance to malaria parasites. In the present study, the aim was to discover novel, effective plant-based extracts for the activity against malaria. Methods Ten plants found in Iran were selected by ethnobotanical survey of medicinal plants. The crude ethanolic extracts were tested for in vitro anti-plasmodial activity against two strains of Plasmodium falciparum: K1 (chloroquine-resistant strain) and CY27 (chloroquine-sensitive strain), using the parasite lactate dehydrogenase (pLDH) assay. The anti-plasmodial activity of the extracts was also assessed in the 4-day suppressive anti-malarial assay in mice inoculated with Plasmodium berghei (ANKA strain). Crude ethanolic extracts showed good anti-plasmodial activity were further fractionated by partitioning in water and dichloromethane. Results Of 10 plant species assayed, three species: Boerhavia elegans (Choisy), Solanum surattense (Burm.f.) and Prosopis juliflora (Sw.) showed promising anti-plasmodial activity in vitro (IC50 ≤ 50 μg/ml) and in vivo with no toxicity. The dichloromethane fraction of three extracts revealed stronger anti-plasmodial activity than the total extracts. Conclusion Anti-plasmodial activities of extracts of B. elegans and S. surattense are reported for the first time. PMID:20462416

  10. Experience of light thin-walled structures improvement in construction

    Science.gov (United States)

    Frolovskaia, A. V.; Deordiev, S. V.; Falk, A.; Klinduh, N. Y.; Terehova, I. I.

    2018-05-01

    The authors on the basis of practical experience have analyzed low-rise construction with the use of energy-saving technologies. Characteristic features of possible variants of frame construction are looked at and described. The relevance of the paper consists in the improvement of the building frame design solution based on the analysis and elimination of disadvantages taking into account consumers’ point of view.

  11. 4-aminopyridyl-based lead compounds targeting CYP51 prevent spontaneous parasite relapse in a chronic model and improve cardiac pathology in an acute model of Trypanosoma cruzi infection.

    Science.gov (United States)

    Calvet, Claudia Magalhaes; Choi, Jun Yong; Thomas, Diane; Suzuki, Brian; Hirata, Ken; Lostracco-Johnson, Sharon; de Mesquita, Liliane Batista; Nogueira, Alanderson; Meuser-Batista, Marcelo; Silva, Tatiana Araujo; Siqueira-Neto, Jair Lage; Roush, William R; de Souza Pereira, Mirian Claudia; McKerrow, James H; Podust, Larissa M

    2017-12-01

    Chagas disease, caused by the protozoan Trypanosoma cruzi, is the leading cause of heart failure in Latin America. The clinical treatment of Chagas disease is limited to two 60 year-old drugs, nifurtimox and benznidazole, that have variable efficacy against different strains of the parasite and may lead to severe side effects. CYP51 is an enzyme in the sterol biosynthesis pathway that has been exploited for the development of therapeutics for fungal and parasitic infections. In a target-based drug discovery program guided by x-ray crystallography, we identified the 4-aminopyridyl-based series of CYP51 inhibitors as being efficacious versus T.cruzi in vitro; two of the most potent leads, 9 and 12, have now been evaluated for toxicity and efficacy in mice. Both acute and chronic animal models infected with wild type or transgenic T. cruzi strains were evaluated. There was no evidence of toxicity in the 28-day dosing study of uninfected animals, as judged by the monitoring of multiple serum and histological parameters. In two acute models of Chagas disease, 9 and 12 drastically reduced parasitemia, increased survival of mice, and prevented liver and heart injury. None of the compounds produced long term sterile cure. In the less severe acute model using the transgenic CL-Brenner strain of T.cruzi, parasitemia relapsed upon drug withdrawal. In the chronic model, parasitemia fell to a background level and, as evidenced by the bioluminescence detection of T. cruzi expressing the red-shifted luciferase marker, mice remained negative for 4 weeks after drug withdrawal. Two immunosuppression cycles with cyclophosphamide were required to re-activate the parasites. Although no sterile cure was achieved, the suppression of parasitemia in acutely infected mice resulted in drastically reduced inflammation in the heart. The positive outcomes achieved in the absence of sterile cure suggest that the target product profile in anti-Chagasic drug discovery should be revised in favor of

  12. Pre-trained convolutional neural networks as feature extractors toward improved malaria parasite detection in thin blood smear images

    Directory of Open Access Journals (Sweden)

    Sivaramakrishnan Rajaraman

    2018-04-01

    Full Text Available Malaria is a blood disease caused by the Plasmodium parasites transmitted through the bite of female Anopheles mosquito. Microscopists commonly examine thick and thin blood smears to diagnose disease and compute parasitemia. However, their accuracy depends on smear quality and expertise in classifying and counting parasitized and uninfected cells. Such an examination could be arduous for large-scale diagnoses resulting in poor quality. State-of-the-art image-analysis based computer-aided diagnosis (CADx methods using machine learning (ML techniques, applied to microscopic images of the smears using hand-engineered features demand expertise in analyzing morphological, textural, and positional variations of the region of interest (ROI. In contrast, Convolutional Neural Networks (CNN, a class of deep learning (DL models promise highly scalable and superior results with end-to-end feature extraction and classification. Automated malaria screening using DL techniques could, therefore, serve as an effective diagnostic aid. In this study, we evaluate the performance of pre-trained CNN based DL models as feature extractors toward classifying parasitized and uninfected cells to aid in improved disease screening. We experimentally determine the optimal model layers for feature extraction from the underlying data. Statistical validation of the results demonstrates the use of pre-trained CNNs as a promising tool for feature extraction for this purpose.

  13. Antitumor effect of malaria parasite infection in a murine Lewis lung cancer model through induction of innate and adaptive immunity.

    Science.gov (United States)

    Chen, Lili; He, Zhengxiang; Qin, Li; Li, Qinyan; Shi, Xibao; Zhao, Siting; Chen, Ling; Zhong, Nanshan; Chen, Xiaoping

    2011-01-01

    Lung cancer is the most common malignancy in humans and its high fatality means that no effective treatment is available. Developing new therapeutic strategies for lung cancer is urgently needed. Malaria has been reported to stimulate host immune responses, which are believed to be efficacious for combating some clinical cancers. This study is aimed to provide evidence that malaria parasite infection is therapeutic for lung cancer. Antitumor effect of malaria infection was examined in both subcutaneously and intravenously implanted murine Lewis lung cancer (LLC) model. The results showed that malaria infection inhibited LLC growth and metastasis and prolonged the survival of tumor-bearing mice. Histological analysis of tumors from mice infected with malaria revealed that angiogenesis was inhibited, which correlated with increased terminal deoxynucleotidyl transferase-mediated (TUNEL) staining and decreased Ki-67 expression in tumors. Through natural killer (NK) cell cytotoxicity activity, cytokine assays, enzyme-linked immunospot assay, lymphocyte proliferation, and flow cytometry, we demonstrated that malaria infection provided anti-tumor effects by inducing both a potent anti-tumor innate immune response, including the secretion of IFN-γ and TNF-α and the activation of NK cells as well as adaptive anti-tumor immunity with increasing tumor-specific T-cell proliferation and cytolytic activity of CD8(+) T cells. Notably, tumor-bearing mice infected with the parasite developed long-lasting and effective tumor-specific immunity. Consequently, we found that malaria parasite infection could enhance the immune response of lung cancer DNA vaccine pcDNA3.1-hMUC1 and the combination produced a synergistic antitumor effect. Malaria infection significantly suppresses LLC growth via induction of innate and adaptive antitumor responses in a mouse model. These data suggest that the malaria parasite may provide a novel strategy or therapeutic vaccine vector for anti-lung cancer

  14. Antitumor effect of malaria parasite infection in a murine Lewis lung cancer model through induction of innate and adaptive immunity.

    Directory of Open Access Journals (Sweden)

    Lili Chen

    Full Text Available BACKGROUND: Lung cancer is the most common malignancy in humans and its high fatality means that no effective treatment is available. Developing new therapeutic strategies for lung cancer is urgently needed. Malaria has been reported to stimulate host immune responses, which are believed to be efficacious for combating some clinical cancers. This study is aimed to provide evidence that malaria parasite infection is therapeutic for lung cancer. METHODOLOGY/PRINCIPAL FINDINGS: Antitumor effect of malaria infection was examined in both subcutaneously and intravenously implanted murine Lewis lung cancer (LLC model. The results showed that malaria infection inhibited LLC growth and metastasis and prolonged the survival of tumor-bearing mice. Histological analysis of tumors from mice infected with malaria revealed that angiogenesis was inhibited, which correlated with increased terminal deoxynucleotidyl transferase-mediated (TUNEL staining and decreased Ki-67 expression in tumors. Through natural killer (NK cell cytotoxicity activity, cytokine assays, enzyme-linked immunospot assay, lymphocyte proliferation, and flow cytometry, we demonstrated that malaria infection provided anti-tumor effects by inducing both a potent anti-tumor innate immune response, including the secretion of IFN-γ and TNF-α and the activation of NK cells as well as adaptive anti-tumor immunity with increasing tumor-specific T-cell proliferation and cytolytic activity of CD8(+ T cells. Notably, tumor-bearing mice infected with the parasite developed long-lasting and effective tumor-specific immunity. Consequently, we found that malaria parasite infection could enhance the immune response of lung cancer DNA vaccine pcDNA3.1-hMUC1 and the combination produced a synergistic antitumor effect. CONCLUSIONS/SIGNIFICANCE: Malaria infection significantly suppresses LLC growth via induction of innate and adaptive antitumor responses in a mouse model. These data suggest that the malaria

  15. Improvement of the cost-benefit analysis algorithm for high-rise construction projects

    Directory of Open Access Journals (Sweden)

    Gafurov Andrey

    2018-01-01

    Full Text Available The specific nature of high-rise investment projects entailing long-term construction, high risks, etc. implies a need to improve the standard algorithm of cost-benefit analysis. An improved algorithm is described in the article. For development of the improved algorithm of cost-benefit analysis for high-rise construction projects, the following methods were used: weighted average cost of capital, dynamic cost-benefit analysis of investment projects, risk mapping, scenario analysis, sensitivity analysis of critical ratios, etc. This comprehensive approach helped to adapt the original algorithm to feasibility objectives in high-rise construction. The authors put together the algorithm of cost-benefit analysis for high-rise construction projects on the basis of risk mapping and sensitivity analysis of critical ratios. The suggested project risk management algorithms greatly expand the standard algorithm of cost-benefit analysis in investment projects, namely: the “Project analysis scenario” flowchart, improving quality and reliability of forecasting reports in investment projects; the main stages of cash flow adjustment based on risk mapping for better cost-benefit project analysis provided the broad range of risks in high-rise construction; analysis of dynamic cost-benefit values considering project sensitivity to crucial variables, improving flexibility in implementation of high-rise projects.

  16. Improvement of the cost-benefit analysis algorithm for high-rise construction projects

    Science.gov (United States)

    Gafurov, Andrey; Skotarenko, Oksana; Plotnikov, Vladimir

    2018-03-01

    The specific nature of high-rise investment projects entailing long-term construction, high risks, etc. implies a need to improve the standard algorithm of cost-benefit analysis. An improved algorithm is described in the article. For development of the improved algorithm of cost-benefit analysis for high-rise construction projects, the following methods were used: weighted average cost of capital, dynamic cost-benefit analysis of investment projects, risk mapping, scenario analysis, sensitivity analysis of critical ratios, etc. This comprehensive approach helped to adapt the original algorithm to feasibility objectives in high-rise construction. The authors put together the algorithm of cost-benefit analysis for high-rise construction projects on the basis of risk mapping and sensitivity analysis of critical ratios. The suggested project risk management algorithms greatly expand the standard algorithm of cost-benefit analysis in investment projects, namely: the "Project analysis scenario" flowchart, improving quality and reliability of forecasting reports in investment projects; the main stages of cash flow adjustment based on risk mapping for better cost-benefit project analysis provided the broad range of risks in high-rise construction; analysis of dynamic cost-benefit values considering project sensitivity to crucial variables, improving flexibility in implementation of high-rise projects.

  17. Regulation of anti-Plasmodium immunity by a LITAF-like transcription factor in the malaria vector Anopheles gambiae.

    Directory of Open Access Journals (Sweden)

    Ryan C Smith

    Full Text Available The mosquito is the obligate vector for malaria transmission. To complete its development within the mosquito, the malaria parasite Plasmodium must overcome the protective action of the mosquito innate immune system. Here we report on the involvement of the Anopheles gambiae orthologue of a conserved component of the vertebrate immune system, LPS-induced TNFα transcription factor (LITAF, and its role in mosquito anti-Plasmodium immunity. An. gambiae LITAF-like 3 (LL3 expression is up-regulated in response to midgut invasion by both rodent and human malaria parasites. Silencing of LL3 expression greatly increases parasite survival, indicating that LL3 is part of an anti-Plasmodium defense mechanism. Electrophoretic mobility shift assays identified specific LL3 DNA-binding motifs within the promoter of SRPN6, a gene that also mediates mosquito defense against Plasmodium. Further experiments indicated that these motifs play a direct role in LL3 regulation of SRPN6 expression. We conclude that LL3 is a transcription factor capable of modulating SRPN6 expression as part of the mosquito anti-Plasmodium immune response.

  18. Using of science technologies for mining machinery constructions' strength improvement

    Science.gov (United States)

    Yurchenko, E. V.; Mehtiev, A. D.; Yugai, V. V.; Bulatbayev, F. N.

    2015-04-01

    Recommendations for strengthening the brake construction in accident dangerous areas of fatigue destruction were developed. Computer modeling was made using the ANSYS program that helps to visualize stained condition of the construction for further practical testing of the strength and reliability improving technology of mining elevating machines' constructions, which are being in a long-term use, with a help of the strengthening elements. A way of construction strengthening, which eliminates the possibility of further fatigue destruction of the brake system elements, because of the load cycle in exploitation process.

  19. A novel progesterone receptor membrane component (PGRMC) in the human and swine parasite Taenia solium: implications to the host-parasite relationship.

    Science.gov (United States)

    Aguilar-Díaz, Hugo; Nava-Castro, Karen E; Escobedo, Galileo; Domínguez-Ramírez, Lenin; García-Varela, Martín; Del Río-Araiza, Víctor H; Palacios-Arreola, Margarita I; Morales-Montor, Jorge

    2018-03-09

    field of host-parasite co-evolution as well as the sex-associated susceptibility to this infection. In a more practical matter, present results may contribute to the molecular design of new drugs with anti-parasite actions.

  20. Anti-parasitic action and elimination of intracellular Toxoplasma gondii in the presence of novel thiosemicarbazone and its 4-thiazolidinone derivatives

    Directory of Open Access Journals (Sweden)

    C.S. Carvalho

    2010-02-01

    Full Text Available Toxoplasma, which infects all eukaryotic cells, is considered to be a good system for the study of drug action and of the behavior of infected host cells. In the present study, we asked if thiosemicarbazone derivatives can be effective against tachyzoites and which morphological and ultrastructural features of host cells and parasites are associated with the destruction of Toxoplasma. The compounds were tested in infected Vero cell culture using concentration screens (0.1 to 20 mM. The final concentration of 1 mM was chosen for biological assay. The following results were obtained: 1 These new derivatives decreased T. gondii infection with an in vitro parasite IC50% of 0.2-0.7 mM, without a significant effect on host cells and the more efficient compounds were 2, 3 (thiosemicarbazone derivatives and 4 (thiazolidinone derivative; 2 The main feature observed during parasite elimination was continuous morphological disorganization of the tachyzoite secretory system, progressive organelle vesiculation, and then complete disruption; 3 Ultrastructural assays also revealed that progressive vesiculation in the cytoplasm of treated parasites did not occur in the host cell; 4 Vesiculation inside the parasite resulted in death, but this feature occurred asynchronously in different intracellular tachyzoites; 5 The death and elimination of T. gondii was associated with features such as apoptosis-like stage, acidification and digestion of parasites into parasitophorous vacuoles. Our results suggest that these new chemical compounds are promising for the elimination of intracellular parasites by mainly affecting tachyzoite development at 1 mM concentration for 24 h of treatment.

  1. Comprehensive Anti-error Study on Power Grid Dispatching Based on Regional Regulation and Integration

    Science.gov (United States)

    Zhang, Yunju; Chen, Zhongyi; Guo, Ming; Lin, Shunsheng; Yan, Yinyang

    2018-01-01

    With the large capacity of the power system, the development trend of the large unit and the high voltage, the scheduling operation is becoming more frequent and complicated, and the probability of operation error increases. This paper aims at the problem of the lack of anti-error function, single scheduling function and low working efficiency for technical support system in regional regulation and integration, the integrated construction of the error prevention of the integrated architecture of the system of dispatching anti - error of dispatching anti - error of power network based on cloud computing has been proposed. Integrated system of error prevention of Energy Management System, EMS, and Operation Management System, OMS have been constructed either. The system architecture has good scalability and adaptability, which can improve the computational efficiency, reduce the cost of system operation and maintenance, enhance the ability of regional regulation and anti-error checking with broad development prospects.

  2. Gap Analysis Approach for Construction Safety Program Improvement

    Directory of Open Access Journals (Sweden)

    Thanet Aksorn

    2007-06-01

    Full Text Available To improve construction site safety, emphasis has been placed on the implementation of safety programs. In order to successfully gain from safety programs, factors that affect their improvement need to be studied. Sixteen critical success factors of safety programs were identified from safety literature, and these were validated by safety experts. This study was undertaken by surveying 70 respondents from medium- and large-scale construction projects. It explored the importance and the actual status of critical success factors (CSFs. Gap analysis was used to examine the differences between the importance of these CSFs and their actual status. This study found that the most critical problems characterized by the largest gaps were management support, appropriate supervision, sufficient resource allocation, teamwork, and effective enforcement. Raising these priority factors to satisfactory levels would lead to successful safety programs, thereby minimizing accidents.

  3. Introduced species: domestic mammals are more significant transmitters of parasites to native mammals than are feral mammals.

    Science.gov (United States)

    Landaeta-Aqueveque, Carlos; Henríquez, Analía; Cattan, Pedro E

    2014-03-01

    The study of parasitism related to biological invasion has focused on attributes and impacts of parasites as invaders and the impact of introduced hosts on endemic parasitism. Thus, there is currently no study of the attributes of hosts which influence the invasiveness of parasites. We aimed to determine whether the degree of domestication of introduced mammalian species - feral introduced mammals, livestock or pets, hereafter 'D' - is important in the spillover of introduced parasites. The literature on introduced parasites of mammals in Chile was reviewed. We designed an index for estimating the relevance of the introduced host species to parasite spillover and determined whether the D of introduced mammals predicted this index. A total of 223 introduced parasite species were found. Our results indicate that domestic mammals have a higher number of introduced parasites and spillover parasites, and the index indicates that these mammals, particularly pets, are more relevant introducers than introduced feral mammals. Further analyses indicated that the higher impact is due to higher parasite richness, a longer time since introduction and wider dispersal, as well as how these mammals are maintained. The greater relevance of domestic mammals is important given that they are basically the same species distributed worldwide and can become the main transmitters of parasites to native mammals elsewhere. This finding also underlines the feasibility of management in order to reduce the transmission of parasites to native fauna through anti-parasitic treatment of domestic mammals, animal-ownership education and the prevention of importing new parasite species. Copyright © 2014 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

  4. Improved quantification of a commercial enzyme-linked immunosorbent assay kit for measuring anti-MDA5 antibody.

    Science.gov (United States)

    Gono, Takahisa; Okazaki, Yuka; Murakami, Akihiro; Kuwana, Masataka

    2018-04-09

    To compare the quantitative performance for measuring anti-MDA5 antibody titer of two enzyme-linked immunosorbent assay (ELISA) systems: an in-house ELISA and the commercial MESACUP TM anti-MDA5 test. Anti-MDA5 antibody titer was measured in sera from 70 patients with dermatomyositis using an in-house ELISA and the MESACUP TM anti-MDA5 test side-by-side. For the commercial ELISA kit, serum samples diluted 1:101 were used according to the manufacturer's protocol, but serial dilutions of sera were also examined to identify the optimal serum dilution for quantification. The anti-MDA5 antibody titers measured by the in-house and commercial ELISAs were positively correlated with each other (r = 0.53, p = .0001), but the antibody titer measured by the commercial ELISA was less sensitive to change after medical treatment, and 37 (80%) of 46 anti-MDA5-positive sera had antibody titer exceeding the quantification range specified by the manufacturer (≥150 index). Experiments using diluted serum samples revealed that diluting the sera 1:5050 improved the quantitative performance of the MESACUP TM anti-MDA5 test, including a better correlation with the in-house ELISA results and an increased sensitivity to change. We improved the ability of the commercial ELISA kit to quantify anti-MDA5 antibody titer by altering its protocol.

  5. Echinococcus multilocularis and Its Intermediate Host: A Model of Parasite-Host Interplay

    Directory of Open Access Journals (Sweden)

    Dominique Angèle Vuitton

    2010-01-01

    Full Text Available Host-parasite interactions in the E. multilocularis-intermediate host model depend on a subtle balance between cellular immunity, which is responsible for host's resistance towards the metacestode, the larval stage of the parasite, and tolerance induction and maintenance. The pathological features of alveolar echinococcosis. the disease caused by E. multilocularis, are related both to parasitic growth and to host's immune response, leading to fibrosis and necrosis, The disease spectrum is clearly dependent on the genetic background of the host as well as on acquired disturbances of Th1-related immunity. The laminated layer of the metacestode, and especially its carbohydrate components, plays a major role in tolerance induction. Th2-type and anti-inflammatory cytokines, IL-10 and TGF-β, as well as nitric oxide, are involved in the maintenance of tolerance and partial inhibition of cytotoxic mechanisms. Results of studies in the experimental mouse model and in patients suggest that immune modulation with cytokines, such as interferon-α, or with specific antigens could be used in the future to treat patients with alveolar echinococcosis and/or to prevent this very severe parasitic disease.

  6. A Study on Nonconformance and Construction Method Improvement for Nuclear Power Plant

    International Nuclear Information System (INIS)

    Kim, Jong Yeob; Roh, Myung Sub

    2014-01-01

    Advanced power reactor was developed by domestic technology, and finally exported to abroad. In order to place the current nuclear power industrial base, construction has played a big role. Without magnificent construction technology, it would have been impossible to get a safe nuclear power plant on time and in budget. Construction industry occupies very large portion of the economy in South Korea and it has been a core of South Korea's economic growth. With a competitive construction industry and advanced nuclear power plant construction know-how, South Korea could provide safe and reliable nuclear power plants in domestic and world. However there are many repairs and number of corrective actions are in actual construction. Thus, this paper suggested the result of nonconformance and construction method improvement for nuclear power plant. Constructional engineering is a kind of science that has a variety of disciplines including structure, geology, mechanical equipment and other fields. Thus, the development of constructional engineering is closely associated with experience from failure and application advanced construction method. The recent experience in nuclear power plants construction has shown that those improved methods are fully applicable and can help shorten the construction schedule. The future of nuclear power plant construction seems to be more encouraged, even though it has many obstacles

  7. Parasites

    Centers for Disease Control (CDC) Podcasts

    2010-05-06

    In this podcast, a listener wants to know what to do if he thinks he has a parasite or parasitic disease.  Created: 5/6/2010 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 5/6/2010.

  8. [Design and development of an online system of parasite's images for training and evaluation].

    Science.gov (United States)

    Yuan-Chun, Mao; Sui, Xu; Jie, Wang; Hua-Yun, Zhou; Jun, Cao

    2017-08-08

    To design and develop an online training and evaluation system for parasitic pathogen recognition. The system was based on a Parasitic Diseases Specimen Image Digitization Construction Database by using MYSQL 5.0 as the system of database development software, and PHP 5 as the interface development language. It was mainly used for online training and evaluation of parasitic pathology diagnostic techniques. The system interface was designed simple, flexible, and easy to operate for medical staff. It enabled full day and 24 hours accessible to online training study and evaluation. Thus, the system broke the time and space constraints of the traditional training models. The system provides a shared platform for the professional training of parasitic diseases, and a reference for other training tasks.

  9. Improving NAVFAC's total quality management of construction drawings with CLIPS

    Science.gov (United States)

    Antelman, Albert

    1991-01-01

    A diagnostic expert system to improve the quality of Naval Facilities Engineering Command (NAVFAC) construction drawings and specification is described. C Language Integrated Production System (CLIPS) and computer aided design layering standards are used in an expert system to check and coordinate construction drawings and specifications to eliminate errors and omissions.

  10. IMPROVING THE QUALITY OF INVESTMENT DESIGN IN INDUSTRIAL CONSTRUCTION

    Directory of Open Access Journals (Sweden)

    I. M. Meylanov

    2017-01-01

    Full Text Available Objectives. The development of a set of practical measures in order to improve the quality of investment design in industrial construction.Methods. The basis of research comprises a project management methodology as well as methods for logical and statistical analysis of decisionmaking in investment activities.Results. A mechanism of inclusion of industrial construction objects into the Federal targeted investment programme is revealed. The sequence of the state expert evaluation of investment projects is determined, which optimises the design solutions aimed at minimising their estimated cost if the investment is made with the involvement of the Federal budget. Qualitative and quantitative criteria are systematised for the integrated assessment of the effectiveness of investment fund usage sent to industrial construction objects.Conclusion. The consistent implementation of the state investment policy is aimed at developing the scientific-technological and scientific-industrial potential of industrial construction by providing favourable conditions for effective innovation activity, selecting rational investment strategies and priority projects aimed at solving urgent problems of improving the competitiveness of construction. Successful implementation of the state investment policy in industrial construction largely depends on the effectiveness of investment design, starting from the accuracy of the formulation of the investment plan (idea, in which the interests of all participants in investment activities are concentrated and taken into account, and to the development of an agreed set of actions to complete the project. A unified register covering the data on the cost and results of investment projects is proposed to be created with the purpose of facilitating decision-making in the process of allocation of the Federal budget funds, planning of state capital investments and approval of project documentation for new industrial construction

  11. Human Albumin Fragments Nanoparticles as PTX Carrier for Improved Anti-cancer Efficacy

    Directory of Open Access Journals (Sweden)

    Liang Ge

    2018-06-01

    Full Text Available For enhanced anti-cancer performance, human serum albumin fragments (HSAFs nanoparticles (NPs were developed as paclitaxel (PTX carrier in this paper. Human albumins were broken into fragments via degradation and crosslinked by genipin to form HSAF NPs for better biocompatibility, improved PTX drug loading and sustained drug release. Compared with crosslinked human serum albumin NPs, the HSAF-NPs showed relative smaller particle size, higher drug loading, and improved sustained release. Cellular and animal results both indicated that the PTX encapsulated HSAF-NPs have shown good anti-cancer performance. And the anticancer results confirmed that NPs with fast cellular internalization showed better tumor inhibition. These findings will not only provide a safe and robust drug delivery NP platform for cancer therapy, but also offer fundamental information for the optimal design of albumin based NPs.

  12. Aufforderung zum Kampf. Geschlechterkonstruktionen und Antisemitismus zum Tanzen bringen! A Call to Arms. Bringing Gender Constructions and Anti-Semitism to Dance!

    Directory of Open Access Journals (Sweden)

    Iris Homann

    2006-07-01

    Full Text Available Der Band Antisemitismus und Geschlecht der Gruppe A.G.Gender-Killer versammelt Untersuchungen über die Bedeutung der Kategorie Geschlecht in antisemitischen Diskursen seit dem 19. Jahrhundert. Ihnen gemeinsam ist die These einer konstitutiven Verknüpfung von Antisemitismus und Geschlechterkonstruktionen. Von der Notwendigkeit eines antifaschistischen gesellschaftlichen Engagements ausgehend, versuchen die Beiträger/-innen einen Brückenschlag zwischen Universität und Politik, Theorie und Praxis. Ihre Ergebnisse belegen die Abrufbarkeit und damit auch die Wirkungsmacht antisemitischer Sexualphantasien und Geschlechterbilder bis heute.The volume Anti-Semitism and Gender (Antisemitismus und Geschlecht published by the group A.G. Gender-Killer collects studies about the meaning of the category of gender in anti-Semitic discourses since the nineteenth century. They share the thesis that sees a constitutive connection between anti-Semitism and gender constructs. The studies attempt to bridge university and politics, theory and practice by beginning with the necessity of an anti-fascist engagement in society. Their results prove that anti-Semitic sexual fantasies and gender images are both immediately recallable and potent today.

  13. Control of parasitic infections among school children in the peri-urban area of Botucatu, São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Regina Coeli Cunha Dórea

    1996-10-01

    Full Text Available Tide prevalence of intestinal parasitosis ivas investigated in a primaiy school located in Rubiâo Júnior, a peri-urban district of Botucatu, São Paulo slate, Brazil, in order to assess the effect of treatment and practical measures of prophylaxis in the control of parasitic infections among 7-to- 18-year-old school children of a low socio-economic status. The first series of parasitological examinations included 219 school children, ef which 123 (56.1 % were found to be infected with one or more parasite species. Eighty- four children canying pathogenic parasites were submitted to various anti-parasitic treatment schedules. We re-evaluated 15 (89 % students after 4 to 6 months post- chemotherapy. The results indicate that the combination of treatment with prophylactic measures has been successful in the control of parasitic infections, since reinfection rates were generally low ( 73-1 % in children infected with most parasite species. The reasons for the apparent failure in the control of infections caused by Hymenolepis nana and Strongyloides stercoralis are discussed.

  14. Advances in the application of genetic manipulation methods to apicomplexan parasites

    Science.gov (United States)

    Apicomplexan parasites such as Babesia, Theileria, Cryptosporidium, and Toxoplasma have a high negative impact on animal health globally, and improved, cost-effective measures to control them are urgently required. These parasites have complex multi-stage life cycles including obligate intracellular...

  15. Parasites and cancers: parasite antigens as possible targets for cancer immunotherapy.

    Science.gov (United States)

    Darani, Hossein Yousofi; Yousefi, Morteza

    2012-12-01

    An adverse relationship between some parasite infections and cancer in the human population has been reported by different research groups. Anticancer activity of some parasites such as Trypanosoma cruzi, Toxoplasma gondii, Toxocara canis, Acantamoeba castellani and Plasmodium yoelii has been shown in experimental animals. Moreover, it has been shown that cancer-associated mucin-type O-glycan compositions are made by parasites, therefore cancers and parasites have common antigens. In this report anticancer activities of some parasites have been reviewed and the possible mechanisms of these actions have also been discussed.

  16. a rational approach for predicting the minimum composition of anti ...

    African Journals Online (AJOL)

    of Cv may deviate from what is predicted by the formula given above are discussed. Extensive literature search on malaria, onchocerciasis and schistosomiasis sub-unit vaccine development ... provides a rational framework for constituting a sub-unit anti-parasite vaccine. ..... vaccine formulation produced greater protection.

  17. Anti-inflammatory thalidomide improves islet grafts survival and functions in a xenogenic environment.

    Directory of Open Access Journals (Sweden)

    Chunguang Chen

    Full Text Available Thalidomide possesses both anti-inflammatory and anti-angiogenic properties. This study investigates its potential application in islet transplantation with a xenogenic transplantation model. Transplantation was performed using C57Bl/6 mice and NMRI nu/nu mice as recipients of porcine islets. Moreover, islet graft vasculature and inflammation were investigated to identify the mechanisms of thalidomide action. In the immunocompetent environment of C57Bl/6 mice, a fast graft rejection was observed. The group treated with thalidomide 200 mg/kg BW per day achieved and maintained euglycemia in the complete observation period for 42 days. The treated mice had more functional islet graft mass with less leukocyte infiltration. The pro-inflammatory TNF-alpha and VEGF content in islet grafted kidneys was significantly lowered by the treatment. By comparison, thalidomide was not effective in improving graft survival in immunocompromised nude mice. It strongly inhibited the VEGF and TNF-alpha-induced endothelial proliferation of isolated pig islets in a dose dependent manner. The magnitude of thalidomide's inhibitory effect was nearly identical to the effect of VEGF- receptor 2 inhibitor SU416 and anti-TNF-receptor 1 neutralizing antibody, and was reversed by sphingosine-1-phosphate. In conclusion, the anti-inflammatory effect of thalidomide improved islet graft survival and function in a transplantation model with a maximum immune barrier.

  18. Enhanced Host-Parasite Resistance Based on Down-Regulation of Phelipanche aegyptiaca Target Genes Is Likely by Mobile Small RNA

    Directory of Open Access Journals (Sweden)

    Neeraj K. Dubey

    2017-09-01

    Full Text Available RNA silencing refers to diverse mechanisms that control gene expression at transcriptional and post-transcriptional levels which can also be used in parasitic pathogens of plants that Broomrapes (Orobanche/Phelipanche spp. are holoparasitic plants that subsist on the roots of a variety of agricultural crops and cause severe negative effects on the yield and yield quality of those crops. Effective methods for controlling parasitic weeds are scarce, with only a few known cases of genetic resistance. In the current study, we suggest an improved strategy for the control of parasitic weeds based on trans-specific gene-silencing of three parasite genes at once. We used two strategies to express dsRNA containing selected sequences of three Phelipanche aegyptiaca genes PaACS, PaM6PR, and PaPrx1 (pma: transient expression using Tobacco rattle virus (TRV:pma as a virus-induced gene-silencing vector and stable expression in transgenic tomato Solanum lycopersicum (Mill. plants harboring a hairpin construct (pBINPLUS35:pma. siRNA-mediated transgene-silencing (20–24 nt was detected in the host plants. Our results demonstrate that the quantities of PaACS and PaM6PR transcripts from P. aegyptiaca tubercles grown on transgenic tomato or on TRV-infected Nicotiana benthamiana plants were significantly reduced. However, only partial reductions in the quantity of PaPrx1 transcripts were observed in the parasite tubercles grown on tomato and on N. benthamiana plants. Concomitant with the suppression of the target genes, there were significant decreases in the number and weight of the parasite tubercles that grew on the host plants, in both the transient and the stable experimental systems. The results of the work carried out using both strategies point to the movement of mobile exogenous siRNA from the host to the parasite, leading to the impaired expression of essential parasite target genes.

  19. Killing of trypanosomatid parasites by a modified bovine host defense peptide, BMAP-18.

    Directory of Open Access Journals (Sweden)

    Lee R Haines

    Full Text Available BACKGROUND: Tropical diseases caused by parasites continue to cause socioeconomic devastation that reverberates worldwide. There is a growing need for new control measures for many of these diseases due to increasing drug resistance exhibited by the parasites and problems with drug toxicity. One new approach is to apply host defense peptides (HDP; formerly called antimicrobial peptides to disease control, either to treat infected hosts, or to prevent disease transmission by interfering with parasites in their insect vectors. A potent anti-parasite effector is bovine myeloid antimicrobial peptide-27 (BMAP-27, a member of the cathelicidin family. Although BMAP-27 is a potent inhibitor of microbial growth, at higher concentrations it also exhibits cytotoxicity to mammalian cells. We tested the anti-parasite activity of BMAP-18, a truncated peptide that lacks the hydrophobic C-terminal sequence of the BMAP-27 parent molecule, an alteration that confers reduced toxicity to mammalian cells. METHODOLOGY/PRINCIPAL FINDINGS: BMAP-18 showed strong growth inhibitory activity against several species and life cycle stages of African trypanosomes, fish trypanosomes and Leishmania parasites in vitro. When compared to native BMAP-27, the truncated BMAP-18 peptide showed reduced cytotoxicity on a wide variety of mammalian and insect cells and on Sodalis glossindius, a bacterial symbiont of the tsetse vector. The fluorescent stain rhodamine 123 was used in immunofluorescence microscopy and flow cytometry experiments to show that BMAP-18 at low concentrations rapidly disrupted mitochondrial potential without obvious alteration of parasite plasma membranes, thus inducing death by apoptosis. Scanning electron microscopy revealed that higher concentrations of BMAP-18 induced membrane lesions in the parasites as early as 15 minutes after exposure, thus killing them by necrosis. In addition to direct killing of parasites, BMAP-18 was shown to inhibit LPS

  20. Helminth allergens, parasite-specific IgE and its protective role in human immunity

    Directory of Open Access Journals (Sweden)

    Colin Matthew Fitzsimmons

    2014-02-01

    Full Text Available The Th2 immune response, culminating in eosinophilia and IgE production, is not only characteristic of allergy but also of infection by parasitic worms (helminths. Anti-parasite IgE has been associated with immunity against a range of helminth infections and many believe that IgE and its receptors evolved to help counter metazoan parasites. Allergens (IgE-antigens are present in only a small minority of protein families and known IgE targets in helminths belong to these same families (e.g. EF-hand proteins, tropomyosin, and PR-1 proteins.During some helminth infection, especially with the well adapted hookworm, the Th2 response is moderated by parasite-expressed molecules. This has been associated with reduced allergy in helminth endemic areas and worm infection or products have been proposed as treatments for allergic conditions. However some infections (especially Ascaris are associated with increased allergy and this has been linked to cross-reactivity between worm proteins (e.g., tropomyosins and highly similar molecules in dust mites and insects. The overlap between allergy and helminth infection is best illustrated in Anisakis simplex, a nematode that when consumed in under-cooked fish can be both an infective helminth and a food allergen. Nearly 20 molecular allergens have been isolated from this species, including tropomyosin (Ani s3 and the EF-hand protein, Ani s troponin.In this review, we highlight aspects of the biology and biochemistry of helminths that may have influenced the evolution of the IgE response. We compare dominant IgE antigens in worms with clinically important environmental allergens and suggest that arrays of such molecules will provide important information on anti-worm immunity as well as allergy.

  1. Identification of a RAC/AKT-like gene in Leishmania parasites as a putative therapeutic target in leishmaniasis.

    Science.gov (United States)

    Varela-M, Rubén E; Ochoa, Rodrigo; Muskus, Carlos E; Muro, Antonio; Mollinedo, Faustino

    2017-10-10

    Leishmaniasis is one of the world's most neglected diseases caused by at least 20 different species of the protozoan parasite Leishmania. Although new drugs have become recently available, current therapy for leishmaniasis is still unsatisfactory. A subgroup of serine/threonine protein kinases named as related to A and C protein kinases (RAC), or protein kinase B (PKB)/AKT, has been identified in several organisms including Trypanosoma cruzi parasites. PKB/AKT plays a critical role in mammalian cell signaling promoting cell survival and is a major drug target in cancer therapy. However, the role of protozoan parasitic PKB/AKT remains to be elucidated. We have found that anti-human AKT antibodies recognized a protein of about 57 kDa in Leishmania spp. parasites. Anti-human phospho-AKT(Thr308) antibodies identified a protein in extracts from Leishmania spp. that was upregulated following parasite exposure to stressful conditions, such as nutrient deprivation or heat shock. Incubation of AKT inhibitor X with Leishmania spp. promastigotes under stressful conditions or with Leishmania-infected macrophages led to parasite cell death. We have identified and cloned a novel gene from Leishmania donovani named Ld-RAC/AKT-like gene, encoding a 510-amino acid protein of approximately 57.6 kDa that shows a 26.5% identity with mammalian AKT1. Ld-RAC/AKT-like protein contains major mammalian PKB/AKT hallmarks, including the typical pleckstrin, protein kinase and AGC kinase domains. Unlike mammalian AKT that contains key phosphorylation sites at Thr308 and Ser473 in the activation loop and hydrophobic motif, respectively, Ld-RAC/AKT-like protein has a Thr residue in both motifs. By domain sequence comparison, we classified AKT proteins from different origins in four major subcategories that included different parasites. Our data suggest that Ld-RAC/AKT-like protein represents a Leishmania orthologue of mammalian AKT involved in parasite stress response and survival, and

  2. Nature is the best source of anti-inflammatory drugs: indexing natural products for their anti-inflammatory bioactivity.

    Science.gov (United States)

    Aswad, Miran; Rayan, Mahmoud; Abu-Lafi, Saleh; Falah, Mizied; Raiyn, Jamal; Abdallah, Ziyad; Rayan, Anwar

    2018-01-01

    The aim was to index natural products for less expensive preventive or curative anti-inflammatory therapeutic drugs. A set of 441 anti-inflammatory drugs representing the active domain and 2892 natural products representing the inactive domain was used to construct a predictive model for bioactivity-indexing purposes. The model for indexing the natural products for potential anti-inflammatory activity was constructed using the iterative stochastic elimination algorithm (ISE). ISE is capable of differentiating between active and inactive anti-inflammatory molecules. By applying the prediction model to a mix set of (active/inactive) substances, we managed to capture 38% of the anti-inflammatory drugs in the top 1% of the screened set of chemicals, yielding enrichment factor of 38. Ten natural products that scored highly as potential anti-inflammatory drug candidates are disclosed. Searching the PubMed revealed that only three molecules (Moupinamide, Capsaicin, and Hypaphorine) out of the ten were tested and reported as anti-inflammatory. The other seven phytochemicals await evaluation for their anti-inflammatory activity in wet lab. The proposed anti-inflammatory model can be utilized for the virtual screening of large chemical databases and for indexing natural products for potential anti-inflammatory activity.

  3. The sight of an adult brood parasite near the nest is an insufficient cue for a honeyguide host to reject foreign eggs.

    Science.gov (United States)

    Tong, Wenfei; Horrocks, Nicholas P C; Spottiswoode, Claire N

    2015-07-01

    Hosts of brood-parasitic birds typically evolve anti-parasitism defences, including mobbing of parasitic intruders at the nest and the ability to recognize and reject foreign eggs from their clutches. The Greater Honeyguide Indicator indicator is a virulent brood parasite that punctures host eggs and kills host young, and accordingly, a common host, the Little Bee-eater Merops pusillus frequently rejects entire clutches that have been parasitized. We predicted that given the high costs of accidentally rejecting an entire clutch, and that the experimental addition of a foreign egg is insufficient to induce this defence, Bee-eaters require the sight of an adult parasite near the nest as an additional cue for parasitism before they reject a clutch. We found that many Little Bee-eater parents mobbed Greater Honeyguide dummies while ignoring barbet control dummies, showing that they recognized them as a threat. Surprisingly, however, neither a dummy Honeyguide nor the presence of a foreign egg, either separately or in combination, was sufficient to stimulate egg rejection.

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

    Directory of Open Access Journals (Sweden)

    Bharat Bashyal

    2017-08-01

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

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

    Science.gov (United States)

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

    2017-08-01

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

  6. [A new method of anti-jamming ability improvement for Michelson Interferometer].

    Science.gov (United States)

    Li, Yang-Jun; Lian, Su-Jie; Shi, Jia; Guo, Ya-Fei; Wang, Gao

    2014-05-01

    In order to improve anti-jamming capability of Michelson interferometer system, replace the traditional structure of the moving mirror scanning was replaced, an interference system based on electro-optic modulation of crystal refractive index was designed to achieve optical path scanning. The system modulated voltage signal on the variable refractive crystal, to generate cyclical changes, changed the refractive index to control optical path difference in the original optical path system. Using electronic scanning to replace of mechanical scanning, improved the system's noise immunity was improved. In the electro-optic modulation process, computed the maximum optical path difference of the system was computed, and analyzed of the crystal thickness and crystal diffraction efficiency of the modulation process were analyzed. The simulation experiment shows that, with the modulation voltage range increasing, the available range of the optical path is also increased, and the system spectrum resolving power will also increase accordingly. Meanwhile, in the modulation process set the modulation range was set to make the energy of diffraction energy losses less than 10% of the total energy, so as to ensure a better signal to noise ratio. Experimental results show that, as the modulation voltage changes, interference fringes occurred continuously moved. When the voltage is further increased, the nonlinear error appears. After non-linear error correction for the system, spectrum resolution reached to 7. 2 cm-1, slightly lower than the original system. But its anti-jamming capability is greatly enhanced, as in the absence of experimental platform for seismic conditions, conventional interferometer relative error is more than 20%, while the relative error of the system is less than 5%, in line with the design requirements. It was proved that the anti-jamming capability of the system was enhanced greatly, when the static electro-optical modulation was used.

  7. Anti-tachycardia therapy can improve altered cardiac adrenergic function in tachycardia-induced cardiomyopathy

    Energy Technology Data Exchange (ETDEWEB)

    Ohkusu, Yasuo; Takahashi, Nobukazu; Ishikawa, Toshiyuki [Yokohama City Univ. (Japan). School of Medicine] [and others

    2002-11-01

    We investigated whether anti-tachycardia therapy might improve the altered cardiac adrenergic and systolic function in tachycardia-induced cardiomyopathy (TC) in contrast to dilated cardiomyopathy (DCM). The subjects were 23 patients with heart failure, consisting of 8 patients with TC (43.6{+-}10.0 yrs) and 15 with DCM (45.3{+-}8.2 yrs). TC was determined as impairment of left ventricular function secondary to chronic or very frequent arrhythmia during more than 10% of the day. All patients were receiving anti-tachycardia treatment. Cardiac {sup 123}I-MIBG uptake was assessed as the heart/mediastinum activity ratio (H/M) before and after treatment. Left ventricular ejection fraction (LVEF) was also assessed. In the baseline study, H/M and LVEF showed no difference between TC and DCM (2.21{+-}0.44 vs. 2.10{+-}0.42, 35.3{+-}13.1 vs. 36.0{+-}10.9%, respectively). After treatment, the degree of change in H/M and LVEF differed significantly (0.41{+-}0.34 vs. 0.08{+-}0.20, 20.5{+-}14.4 vs. -2.1{+-}9.6%, p<0.01). In TC, heart failure improved after a shorter duration of treatment (p<0.05). In conclusion, anti-tachycardia therapy can improve altered cardiac adrenergic function and systolic function in patients with TC over a shorter period than in those with DCM. (author)

  8. Volutin granules of Eimeria parasites are acidic compartments and have physiological and structural characteristics similar to acidocalcisomes

    Science.gov (United States)

    Medeiros, Lia Carolina Soares; Gomes, Fabio; Maciel, Luis Renato Maia; Seabra, Sergio Henrique; Docampo, Roberto; Moreno, Silvia; Plattner, Helmut; Hentschel, Joachim; Kawazoe, Urara; Barrabin, Hector; de Souza, Wanderley; DaMatta, Renato Augusto; Miranda, Kildare

    2012-01-01

    The structural organization of parasites has been the subject of investigation by many groups and has lead to the identification of structures and metabolic pathways that may represent targets for anti-parasitic drugs. A specific group of organelles named acidocalcisomes has been identified in a number of organisms, including the apicomplexan parasites such as Toxoplasma and Plasmodium, where they have been shown to be involved in cation homeostasis, polyphosphate metabolism, and osmoregulation. Their structural counterparts in the apicomplexan parasite Eimeria have not been fully characterized. In this work, the ultrastructural and chemical properties of acidocalcisomes in Eimeria were characterized. Electron microscopy analysis of Eimeria parasites showed the dense organelles called volutin granules similar to acidocalcisomes. Immunolocalization of the vacuolar proton pyrophosphatase, considered as a marker for acidocalcisomes, showed labeling in vesicles of size and distribution similar to the dense organelles seen by electron microscopy. Spectrophotometric measurements of the kinetics of proton uptake showed a vacuolar proton pyrophosphatase activity. X-ray mapping revealed significant amounts of Na, Mg, P, K, Ca, and Zn in their matrix. The results suggest that volutin granules of Eimeria parasites are acidic, dense organelles and possess structural and chemical properties analogous to those of other acidocalcisomes, suggesting a similar functional role in these parasites. PMID:21699625

  9. Anti-trypanosomal activity of pentacyclic triterpenes isolated from Austroplenckia populnea (Celastraceae).

    Science.gov (United States)

    Duarte, Lucienir Pains; Vieira Filho, Sidney Augusto; Silva, Grácia Divina de Fátima; de Sousa, José Rego; Pinto, Artur da Silveira

    2002-01-01

    Four pentacyclic triterpenes isolated from Austroplenckia populnea and four compounds of known anti T. cruzi or anti-malarial activity were tested. Of those triterpenes tested 20alpha-hydroxy-tingenone showed high activity, epikatonic acid was less active, while populnilic and populninic acids were inactive against the trypanosome of the subgenus Schizotrypanum tested. Benzonidazole, nifurtimox, ketoconazole and primaquine presented a remarkable dose-dependent inhibitory effect reaching practically to a total growth inhibition of the parasite at the end of incubation time. The trypanosome tested appear to be a suitable model for preliminary screen for anti T. (S.) cruzi compounds.

  10. Fishing drives declines in fish parasite diversity and has variable effects on parasite abundance.

    Science.gov (United States)

    Wood, Chelsea L; Sandin, Stuart A; Zgliczynski, Brian; Guerra, Ana Sofía; Micheli, Fiorenza

    2014-07-01

    Despite the ubiquity and ecological importance of parasites, relatively few studies have assessed their response to anthropogenic environmental change. Heuristic models have predicted both increases and decreases in parasite abundance in response to human disturbance, with empirical support for both. However, most studies focus on one or a few selected parasite species. Here, we assess the abundance of parasites of seven species of coral reef fishes collected from three fished and three unfished islands of the Line Islands archipelago in the central equatorial Pacific. Because we chose fish hosts that spanned different trophic levels, taxonomic groups, and body sizes, we were able to compare parasite responses across a broad cross section of the total parasite community in the presence and absence of fishing, a major human impact on marine ecosystems. We found that overall parasite species richness was substantially depressed on fished islands, but that the response of parasite abundance varied among parasite taxa: directly transmitted parasites were significantly more abundant on fished than on unfished islands, while the reverse was true for trophically transmitted parasites. This probably arises because trophically transmitted parasites require multiple host species, some of which are the top predators most sensitive to fishing impacts. The increase in directly transmitted parasites appeared to be due to fishing-driven compensatory increases in the abundance of their hosts. Together, these results provide support for the predictions of both heuristic models, and indicate that the direction of fishing's impact on parasite abundance is mediated by parasite traits, notably parasite transmission strategies.

  11. Paradigms for parasite conservation.

    Science.gov (United States)

    Dougherty, Eric R; Carlson, Colin J; Bueno, Veronica M; Burgio, Kevin R; Cizauskas, Carrie A; Clements, Christopher F; Seidel, Dana P; Harris, Nyeema C

    2016-08-01

    Parasitic species, which depend directly on host species for their survival, represent a major regulatory force in ecosystems and a significant component of Earth's biodiversity. Yet the negative impacts of parasites observed at the host level have motivated a conservation paradigm of eradication, moving us farther from attainment of taxonomically unbiased conservation goals. Despite a growing body of literature highlighting the importance of parasite-inclusive conservation, most parasite species remain understudied, underfunded, and underappreciated. We argue the protection of parasitic biodiversity requires a paradigm shift in the perception and valuation of their role as consumer species, similar to that of apex predators in the mid-20th century. Beyond recognizing parasites as vital trophic regulators, existing tools available to conservation practitioners should explicitly account for the unique threats facing dependent species. We built upon concepts from epidemiology and economics (e.g., host-density threshold and cost-benefit analysis) to devise novel metrics of margin of error and minimum investment for parasite conservation. We define margin of error as the risk of accidental host extinction from misestimating equilibrium population sizes and predicted oscillations, while minimum investment represents the cost associated with conserving the additional hosts required to maintain viable parasite populations. This framework will aid in the identification of readily conserved parasites that present minimal health risks. To establish parasite conservation, we propose an extension of population viability analysis for host-parasite assemblages to assess extinction risk. In the direst cases, ex situ breeding programs for parasites should be evaluated to maximize success without undermining host protection. Though parasitic species pose a considerable conservation challenge, adaptations to conservation tools will help protect parasite biodiversity in the face of

  12. Leishmania eukaryotic initiation factor (LeIF inhibits parasite growth in murine macrophages.

    Directory of Open Access Journals (Sweden)

    Olga Koutsoni

    Full Text Available The leishmaniases constitute neglected global public health problems that require adequate control measures, prophylactic clinical vaccines and effective and non-toxic drug treatments. In this study, we explored the potential of Leishmania infantum eukaryotic initiation factor (LieIF, an exosomal protein, as a novel anti-infective therapeutic molecule. More specifically, we assessed the efficacy of recombinant LieIF, in combination with recombinant IFN-γ, in eliminating intracellular L. donovani parasites in an in vitro macrophage model. J774A.1 macrophages were initially treated with LieIF/IFN-γ prior to in vitro infection with L. donovani stationary phase promastigotes (pre-infection treatment, and resistance to infection was observed 72 h after infection. J774A.1 macrophages were also treated with LieIF/IFN-γ after L. donovani infection (post-infection treatment, and resistance to infection was also observed at both time points tested (19 h and 72 h after infection. To elucidate the LieIF/IFN-γ-induced mechanism(s that mediate the reduction of intracellular parasite growth, we examined the generation of potent microbicidal molecules, such as nitric oxide (NO and reactive oxygen species (ROS, within infected macrophages. Furthermore, macrophages pre-treated with LieIF/IFN-γ showed a clear up-regulation in macrophage inflammatory protein 1α (MIP-1α as well as tumor necrosis factor alpha (TNF-α expression. However, significant different protein levels were not detected. In addition, macrophages pre-treated with LieIF/IFN-γ combined with anti-TNF-α monoclonal antibody produced significantly lower amounts of ROS. These data suggest that during the pre-treatment state, LieIF induces intramacrophage parasite growth inhibition through the production of TNF-α, which induces microbicidal activity by stimulating NO and ROS production. The mechanisms of NO and ROS production when macrophages are treated with LieIF after infection are probably

  13. 7 CFR 3015.16 - Construction and facility improvement.

    Science.gov (United States)

    2010-01-01

    ... subgrant. (b) Bids and contracts or subcontracts of $100,000 or less. Unless otherwise required by law, the... payment bonds. (c) Bids and contracts or subcontracts exceeding $100,000. Unless otherwise required by law... § 3015.16 Construction and facility improvement. (a) Scope. This section covers requirements for bid...

  14. Combined antiparasitic and anti-inflammatory effects of the natural polyphenol curcumin on turbot scuticociliatosis.

    Science.gov (United States)

    Mallo, N; DeFelipe, A P; Folgueira, I; Sueiro, R A; Lamas, J; Leiro, J M

    2017-02-01

    The histiophagous scuticociliate Philasterides dicentrarchi is the aetiological agent of scuticociliatosis, a parasitic disease of farmed turbot. Curcumin, a polyphenol from Curcuma longa (turmeric), is known to have antioxidant and anti-inflammatory properties. We investigated the in vitro effects of curcumin on the growth of P. dicentrarchi and on the production of pro-inflammatory cytokines in turbot leucocytes activated by parasite cysteine proteases. At 100 μm, curcumin had a cytotoxic effect and completely inhibited the growth of the parasite. At 50 μm, curcumin inhibited the protease activity of the parasite and expression of genes encoding two virulence-associated proteases: leishmanolysin-like peptidase and cathepsin L-like. At concentrations between 25 and 50 μm, curcumin inhibited the expression of S-adenosyl-L-homocysteine hydrolase, an enzyme involved in the biosynthesis of the amino acids methionine and cysteine. At 100 μm, curcumin inhibited the expression of the cytokines tumour necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β) produced in turbot leucocytes activated by parasite proteases. Results show that curcumin has a dual effect on scuticociliatosis: an antiparasitic effect on the catabolism and anabolism of ciliate proteins, and an anti-inflammatory effect that inhibits the production of proinflammatory cytokines in the host. The present findings suggest the potential usefulness of this polyphenol in treating scuticociliatosis. © 2016 John Wiley & Sons Ltd.

  15. Analysis of a summary network of co-infection in humans reveals that parasites interact most via shared resources

    OpenAIRE

    Griffiths, Emily C; Pedersen, Amy B; Fenton, Andy; Petchey, Owen L

    2014-01-01

    Simultaneous infection by multiple parasite species (viruses, bacteria, helminths, protozoa or fungi) is commonplace. Most reports show co-infected humans to have worse health than those with single infections. However, we have little understanding of how co-infecting parasites interact within human hosts. We used data from over 300 published studies to construct a network that offers the first broad indications of how groups of co-infecting parasites tend to interact. The network had three l...

  16. Anti-Trypanosoma, anti-Leishmania and cytotoxic activities of natural products from Psidium brownianum Mart. ex DC. and Psidium guajava var. Pomifera analysed by LC-MS.

    Science.gov (United States)

    de Souza, Celestina Elba Sobral; da Silva, Ana Raquel Pereira; Gomez, Maria Celeste Vega; Rolóm, Míriam; Coronel, Cathia; da Costa, José Galberto Martins; Sousa, Amanda K; Rolim, Larissa A; de Souza, Francisco Hugo Sobral; Coutinho, Henrique Douglas Melo

    2017-12-01

    Neglected diseases are those that are prevalent in developing countries, even with a rich biodiversity. These diseases still persist because of the lack of scientific studies, government negligence or failures of the public health system. This study aims to identify the composition of extracts and fractions from Psidium brownianum and Psidium guajava through LC-MS, to evaluate its in vitro anti-parasitic and cytotoxic activity against Trypanosoma cruzi, Leishmania brasiliensis and L. infantum epismastigote and promastigote forms, as well as mammalian cells. The results showed the presence of chemical constituents in the two Psidium species as quercetin, myricetin and gallic acid derivatives. The P. brownianum extract and fractions showed low toxicity at all tested concentrations and all samples were effective at the concentration of 1000μg/mL against the parasites, with the extract being the most efficient against the L. infantum promastigote form. The ethanolic extract, and the flavonoid and tannic fractions, from P. guajava showed low toxicity for the fibroblasts. All samples showed effectiveness at the highest concentration tested and the extract was more effective against the promastigote forms tested. The results showed that the species Psidium brownianum and Psidium guajava demonstrated an anti-parasitic activity against the T. cruzi, L. brasiliensis and L. infantum parasite cell lines indicating these species as an alternative therapy given their efficacy in the in vitro assays performed, opening the possibility for new biological studies to further this knowledge through in vivo assays. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Gastrointestinal parasites and Trypanosoma evansi in buffaloes

    International Nuclear Information System (INIS)

    Sani, R.A.; Chandrawathani, P.; Rosli, M.

    1990-01-01

    Gastrointestinal parasitism is common in buffalo calves. The effect of helminths on growth was studied by administration of an anthelmintic to buffalo calves following natural infections with gastrointestinal parasites. In studies conducted on calves belonging to an institute and a smallholder farmer, the treated calves showed improved weight gains. Serial parasitic examinations showed these animals had moderate to high faecal counts with Strongyloides, Toxocara vitulorum and Haemonchus eggs and Eimeria oocytes. In another study, there was no live weight advantage in treated over untreated calves. Few animals in this study had evidence of parasites and even those which were infested had low faecal egg counts. Hence, in general, helminths at certain levels of infection do affect the live weight gains of young buffalo calves. The prevalence of Trypanosoma evansi, as assessed parasitologically using the haematocrit centrifugation technique and mice inoculation, was 2.7 and 1%, respectively, in cattle and buffaloes. The serological prevalence using the enzyme linked immunosorbent assay was 35 and 2% for cattle and buffaloes, respectively. (author). 6 refs, 5 figs, 2 tabs

  18. Application of a widely-used tropical anti-worm agent, mebendazole ...

    African Journals Online (AJOL)

    well-known anti-parasitic drug widely used in the tropical areas, inhibits cancer cell growth. Preclinical .... Bcl-2 and related proteins, encoded by the Bcl-2 oncogene ... homodimer that acts as an apoptosis inducer, while the ... Figure 1: Schematic presentation of proposed mebendazole anticancer mechanisms of action in.

  19. Application of a widely-used tropical anti-worm agent, mebendazole ...

    African Journals Online (AJOL)

    Although clinical trials have not been completed, it has already been confirmed that mebendazole, a well-known anti-parasitic drug widely used in the tropical areas, inhibits cancer cell growth. Preclinical studies show that mebendazole notably impedes the growth of malignant and metastatic tumors such as osteosarcoma ...

  20. Sustainability of a Compartmentalized Host-Parasite Replicator System under Periodic Washout-Mixing Cycles

    Directory of Open Access Journals (Sweden)

    Taro Furubayashi

    2018-01-01

    Full Text Available The emergence and dominance of parasitic replicators are among the major hurdles for the proliferation of primitive replicators. Compartmentalization of replicators is proposed to relieve the parasite dominance; however, it remains unclear under what conditions simple compartmentalization uncoupled with internal reaction secures the long-term survival of a population of primitive replicators against incessant parasite emergence. Here, we investigate the sustainability of a compartmentalized host-parasite replicator (CHPR system undergoing periodic washout-mixing cycles, by constructing a mathematical model and performing extensive simulations. We describe sustainable landscapes of the CHPR system in the parameter space and elucidate the mechanism of phase transitions between sustainable and extinct regions. Our findings revealed that a large population size of compartments, a high mixing intensity, and a modest amount of nutrients are important factors for the robust survival of replicators. We also found two distinctive sustainable phases with different mixing intensities. These results suggest that a population of simple host–parasite replicators assumed before the origin of life can be sustained by a simple compartmentalization with periodic washout-mixing processes.

  1. The Ecology of Parasite-Host Interactions at Montezuma Well National Monument, Arizona - Appreciating the Importance of Parasites

    Science.gov (United States)

    O'Brien, Chris; van Riper, Charles

    2009-01-01

    activities alter these associations, scientists usually make inferences by methods of statistical hypotheses testing. This type of hypothesis testing places additional importance on the analysis and interpretation of parasite-host interactions. We address these ideas in this report, focusing on the following questions: (1) How do two parasites with complex life cycles alter the behavior of a novel amphipod host, and how do host and non-host predators respond to infected amphipod prey? (2) Does human recreation affect spatial patterns of infection in an otherwise natural ecosystem? (3) How is hypothesis-testing applied in studies of wildlife disease? (4) What conclusions can we make about the relative usefulness of these methodologies? and (5) How can the analysis and interpretation of wildlife disease studies be improved? Each chapter of this report contains its own literature-cited section, with tables included in appendixes at the end of the full report.

  2. Non-traditional Forages in a Managed Grazing System for Control of Gastrointestinal Parasites in Sheep: Preliminary Work

    Science.gov (United States)

    This project compared lambs grazing forage chicory (Cichorium intybus L.) with lambs grazing brown mid-rib forage sorghum (Sorghum bicolor (L.) Moench.) x sudangrass (Sorghum sudanense Piper) hybrid (BMR) to determine if anti-parasitic effects of chicory could be demonstrated. Lambs grazed these fo...

  3. Structural basis of malaria parasite lysyl-tRNA synthetase inhibition by cladosporin.

    Science.gov (United States)

    Khan, Sameena; Sharma, Arvind; Belrhali, Hassan; Yogavel, Manickam; Sharma, Amit

    2014-06-01

    Malaria parasites inevitably develop drug resistance to anti-malarials over time. Hence the immediacy for discovering new chemical scaffolds to include in combination malaria drug therapy. The desirable attributes of new chemotherapeutic agents currently include activity against both liver and blood stage malaria parasites. One such recently discovered compound called cladosporin abrogates parasite growth via inhibition of Plasmodium falciparum lysyl-tRNA synthetase (PfKRS), an enzyme central to protein translation. Here, we present crystal structure of ternary PfKRS-lysine-cladosporin (PfKRS-K-C) complex that reveals cladosporin's remarkable ability to mimic the natural substrate adenosine and thereby colonize PfKRS active site. The isocoumarin fragment of cladosporin sandwiches between critical adenine-recognizing residues while its pyran ring fits snugly in the ribose-recognizing cavity. PfKRS-K-C structure highlights ample space within PfKRS active site for further chemical derivatization of cladosporin. Such derivatives may be useful against additional human pathogens that retain high conservation in cladosporin chelating residues within their lysyl-tRNA synthetase.

  4. Parasites as prey

    NARCIS (Netherlands)

    Goedknegt, M.A.; Welsh, J.E.; Thieltges, D.W.

    2012-01-01

    Parasites are usually considered to use their hosts as a resource for energy. However, there is increasing awareness that parasites can also become a resource themselves and serve as prey for other organisms. Here we describe various types of predation in which parasites act as prey for other

  5. Impacts of parasites in early life: contrasting effects on juvenile growth for different family members.

    Directory of Open Access Journals (Sweden)

    Thomas E Reed

    Full Text Available Parasitism experienced early in ontogeny can have a major impact on host growth, development and future fitness, but whether siblings are affected equally by parasitism is poorly understood. In birds, hatching asynchrony induced by hormonal or behavioural mechanisms largely under parental control might predispose young to respond to infection in different ways. Here we show that parasites can have different consequences for offspring depending on their position in the family hierarchy. We experimentally treated European Shag (Phalacrocorax aristoteli nestlings with the broad-spectrum anti-parasite drug ivermectin and compared their growth rates with nestlings from control broods. Average growth rates measured over the period of linear growth (10 days to 30 days of age and survival did not differ for nestlings from treated and control broods. However, when considering individuals within broods, parasite treatment reversed the patterns of growth for individual family members: last-hatched nestlings grew significantly slower than their siblings in control nests but grew faster in treated nests. This was at the expense of their earlier-hatched brood-mates, who showed an overall growth rate reduction relative to last-hatched nestlings in treated nests. These results highlight the importance of exploring individual variation in the costs of infection and suggest that parasites could be a key factor modulating within-family dynamics, sibling competition and developmental trajectories from an early age.

  6. Consumption of high-dose vitamin C (1250 mg per day) enhances functional and structural properties of serum lipoprotein to improve anti-oxidant, anti-atherosclerotic, and anti-aging effects via regulation of anti-inflammatory microRNA.

    Science.gov (United States)

    Kim, Seong-Min; Lim, So-Mang; Yoo, Jeong-Ah; Woo, Moon-Jea; Cho, Kyung-Hyun

    2015-11-01

    Background Although the health effects of vitamin C are well known, its physiological effect on serum lipoproteins and microRNA still remain to be investigated, especially daily consumption of a high dosage. Objectives To investigate the physiological effect of vitamin C on serum lipoprotein metabolism in terms of its anti-oxidant and anti-glycation activities, and gene expression via microRNA regulation. Methods We analyzed blood parameters and lipoprotein parameters in young subjects (n = 46, 22 ± 2 years old) including smokers who consumed a high dose of vitamin C (1250 mg) daily for 8 weeks. Results Antioxidant activity of serum was enhanced with the elevation of Vit C content in plasma during 8 weeks consumption. In the LDL fraction, the apo-B48 band disappeared at 8 weeks post-consumption in all subjects. In the HDL fraction, apoA-I expression was enhanced by 20% at 8 weeks, especially in male smokers. In the lipoprotein fraction, all subjects showed significantly reduced contents of advanced glycated end products and reactive oxygen species (ROS). Triglyceride (TG) contents in each LDL and HDL fraction were significantly reduced in all groups following the Vit C consumption, suggesting that the lipoprotein was changed to be more anti-inflammatory and atherogenic properties. Phagocytosis of LDL, which was purified from each individual, into macrophages was significantly reduced at 8-weeks post-consumption of vitamin C. Anti-inflammatory and anti-senescence effects of HDL from all subjects were enhanced after the 8-weeks consumption. The expression level of microRNA 155 in HDL3 was reduced by 49% and 75% in non-smokers and smokers, respectively. Conclusion The daily consumption of a high dose of vitamin C for 8 weeks resulted in enhanced anti-senescence and anti-atherosclerotic effects via an improvement of lipoprotein parameters and microRNA expression through anti-oxidation and anti-glycation, especially in smokers.

  7. Parasites: Water

    Science.gov (United States)

    ... Consultations, and General Public. Contact Us Parasites Home Water Language: English Español (Spanish) Recommend on Facebook Tweet Share Compartir Parasites can live in natural water sources. When outdoors, treat your water before drinking ...

  8. Improving concrete overlay construction.

    Science.gov (United States)

    2010-03-01

    Several road construction projects involving concrete overlays at the state and county levels in Iowa in 2009 were studied for : construction techniques and methods. The projects that were evaluated consisted of sites in four Iowa counties: Osceola, ...

  9. Bandwidth-Enhanced Low-Profile Antenna with Parasitic Patches

    Directory of Open Access Journals (Sweden)

    Son Xuat Ta

    2017-01-01

    Full Text Available This paper presents low-profile broadband antennas, which are composed of four parasitic patches placed between planar radiators and a perfect electric conductor ground plane. Two types of planar radiators, a conventional dipole and a crossed dipole, are employed to produce linearly polarized (LP and circularly polarized (CP radiations, respectively. The radiator and parasitic patches are realized on thin substrates to lower the cost. Owing to the presence of parasitic patches, the antenna performance improves in terms of profile reduction, resonant frequency decrease, and bandwidth enhancement. These improvements are discussed and confirmed computationally and experimentally. The LP design with the overall dimensions of 120 mm × 120 mm × 16.3 mm (0.64λ0 × 0.64λ0 × 0.087λ0 at 1.6 GHz has a |S11|  96%. The CP design, which has the same physical size as the LP case, has a |S11|  90%.

  10. Physical evaluation of prototype high-performance anti-scatter grids: potential for improved digital radiographic image quality

    International Nuclear Information System (INIS)

    Fetterly, Kenneth A; Schueler, Beth A

    2009-01-01

    Grid evaluation for a screen-film x-ray system has typically included independent measurement of the opposing contrast improvement factor and Bucky factor. Neither of these metrics, however, is appropriate when assessing grid performance in a digital imaging environment. For digital radiographic systems, the benefit of an anti-scatter grid is well characterized by the quantum signal-to-noise ratio improvement factor (K SNR ) provided by the grid. The purpose of this work was to measure K SNR of prototype grids designed for use with digital radiographic systems. The prototype grids had 5 mm tall lead septa, fiber interspace material, line rate N = 25 and 36 cm -1 and ratio r = 15 and 21, respectively. The primary and scatter transmission properties of the grids were measured, and K SNR was evaluated over a phantom thickness range of 10-50 cm. To provide a comparison, the K SNR of similarly constructed N44r15 and N80r15 grids is also reported. K SNR of the prototype grids ranged from 1.4 for the 10 cm phantom to 2.4 for the 50 cm phantom. For the thickest phantom, the SNR improvement factor of the prototype grids was 18-83% higher than that of the N44r15 and N80r15 grids, respectively. (note)

  11. Cell based assays for anti-Plasmodium activity evaluation.

    Science.gov (United States)

    Mokgethi-Morule, Thabang; N'Da, David D

    2016-03-10

    Malaria remains one of the most common and deadly infectious diseases worldwide. The severity of this global public health challenge is reflected by the approximately 198 million people, who were reportedly infected in 2013 and by the more than 584,000 related deaths in that same year. The rising emergence of drug resistance towards the once effective artemisinin combination therapies (ACTs) has become a serious concern and warrants more robust drug development strategies, with the objective of eradicating malaria infections. The intricate biology and life cycle of Plasmodium parasites complicate the understanding of the disease in such a way that would enhance the development of more effective chemotherapies that would achieve radical clinical cure and that would prevent disease relapse. Phenotypic cell based assays have for long been a valuable approach and involve the screening and analysis of diverse compounds with regards to their activities towards whole Plasmodium parasites in vitro. To achieve the Millennium Development Goal (MDG) of malaria eradication by 2020, new generation drugs that are active against all parasite stages (erythrocytic (blood), exo-erythrocytic (liver stages and gametocytes)) are needed. Significant advances are being made in assay development to overcome some of the practical challenges of assessing drug efficacy, particularly in the liver and transmission stage Plasmodium models. This review discusses primary screening models and the fundamental progress being made in whole cell based efficacy screens of anti-malarial activity. Ongoing challenges and some opportunities for improvements in assay development that would assist in the discovery of effective, safe and affordable drugs for malaria treatments are also discussed. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. ConStruct: Improved construction of RNA consensus structures

    Directory of Open Access Journals (Sweden)

    Steger Gerhard

    2008-04-01

    Full Text Available Abstract Background Aligning homologous non-coding RNAs (ncRNAs correctly in terms of sequence and structure is an unresolved problem, due to both mathematical complexity and imperfect scoring functions. High quality alignments, however, are a prerequisite for most consensus structure prediction approaches, homology searches, and tools for phylogeny inference. Automatically created ncRNA alignments often need manual corrections, yet this manual refinement is tedious and error-prone. Results We present an extended version of CONSTRUCT, a semi-automatic, graphical tool suitable for creating RNA alignments correct in terms of both consensus sequence and consensus structure. To this purpose CONSTRUCT combines sequence alignment, thermodynamic data and various measures of covariation. One important feature is that the user is guided during the alignment correction step by a consensus dotplot, which displays all thermodynamically optimal base pairs and the corresponding covariation. Once the initial alignment is corrected, optimal and suboptimal secondary structures as well as tertiary interaction can be predicted. We demonstrate CONSTRUCT's ability to guide the user in correcting an initial alignment, and show an example for optimal secondary consensus structure prediction on very hard to align SECIS elements. Moreover we use CONSTRUCT to predict tertiary interactions from sequences of the internal ribosome entry site of CrP-like viruses. In addition we show that alignments specifically designed for benchmarking can be easily be optimized using CONSTRUCT, although they share very little sequence identity. Conclusion CONSTRUCT's graphical interface allows for an easy alignment correction based on and guided by predicted and known structural constraints. It combines several algorithms for prediction of secondary consensus structure and even tertiary interactions. The CONSTRUCT package can be downloaded from the URL listed in the Availability and

  13. Improvement of Construction Project Management Processes

    Directory of Open Access Journals (Sweden)

    Nazarko, J.

    2017-07-01

    Full Text Available The common denominator of the five papers published in the current edition of the Journal of Engineering, Project, and Production Management is the improvement of construction project management processes for effective use of resources. Execution of proper project management processes is widely recognized as a key success factor influencing likelihood of project success (Alleman, 2014. It is noticeable that four out of five papers in this issue of the Journal are authored or co-authored by Iranian researchers from the same Institute but their conclusions bear importance that cannot be limited to the authors’ region.

  14. The sight of an adult brood parasite near the nest is an insufficient cue for a honeyguide host to reject foreign eggs

    Science.gov (United States)

    Tong, Wenfei; Horrocks, Nicholas P C; Spottiswoode, Claire N

    2015-01-01

    Hosts of brood-parasitic birds typically evolve anti-parasitism defences, including mobbing of parasitic intruders at the nest and the ability to recognize and reject foreign eggs from their clutches. The Greater Honeyguide Indicator indicator is a virulent brood parasite that punctures host eggs and kills host young, and accordingly, a common host, the Little Bee-eater Merops pusillus frequently rejects entire clutches that have been parasitized. We predicted that given the high costs of accidentally rejecting an entire clutch, and that the experimental addition of a foreign egg is insufficient to induce this defence, Bee-eaters require the sight of an adult parasite near the nest as an additional cue for parasitism before they reject a clutch. We found that many Little Bee-eater parents mobbed Greater Honeyguide dummies while ignoring barbet control dummies, showing that they recognized them as a threat. Surprisingly, however, neither a dummy Honeyguide nor the presence of a foreign egg, either separately or in combination, was sufficient to stimulate egg rejection. PMID:26300559

  15. Parasites in marine food webs

    Science.gov (United States)

    Lafferty, Kevin D.

    2013-01-01

    Most species interactions probably involve parasites. This review considers the extent to which marine ecologists should consider parasites to fully understand marine communities. Parasites are influential parts of food webs in estuaries, temperate reefs, and coral reefs, but their ecological importance is seldom recognized. Though difficult to observe, parasites can have substantial biomass, and they can be just as common as free-living consumers after controlling for body mass and trophic level. Parasites have direct impacts on the energetics of their hosts and some affect host behaviors, with ecosystem-level consequences. Although they cause disease, parasites are sensitive components of ecosystems. In particular, they suffer secondary extinctions due to biodiversity loss. Some parasites can also return to a system after habitat restoration. For these reasons, parasites can make good indicators of ecosystem integrity. Fishing can indirectly increase or decrease parasite populations and the effects of climate change on parasites are likely to be equally as complex.

  16. Characterizing Ancylostoma caninum transcriptome and exploring nematode parasitic adaptation

    Directory of Open Access Journals (Sweden)

    Hawdon John

    2010-05-01

    Full Text Available Abstract Background Hookworm infection is one of the most important neglected diseases in developing countries, with approximately 1 billion people infected worldwide. To better understand hookworm biology and nematode parasitism, the present study generated a near complete transcriptome of the canine hookworm Ancylostoma caninum to a very high coverage using high throughput technology, and compared it to those of the free-living nematode Caenorhabditis elegans and the parasite Brugia malayi. Results The generated transcripts from four developmental stages, infective L3, serum stimulated L3, adult male and adult female, covered 93% of the A. caninum transcriptome. The broad diversity among nematode transcriptomes was confirmed, and an impact of parasitic adaptation on transcriptome diversity was inferred. Intra-population analysis showed that A. caninum has higher coding sequence diversity than humans. Examining the developmental expression profiles of A. caninum revealed major transitions in gene expression from larval stages to adult. Adult males expressed the highest number of selectively expressed genes, but adult female expressed the highest number of selective parasitism-related genes. Genes related to parasitism adaptation and A. caninum specific genes exhibited more expression selectivity while those conserved in nematodes tend to be consistently expressed. Parasitism related genes were expressed more selectively in adult male and female worms. The comprehensive analysis of digital expression profiles along with transcriptome comparisons enabled identification of a set of parasitism genes encoding secretory proteins in animal parasitic nematode. Conclusions This study validated the usage of deep sequencing for gene expression profiling. Parasitic adaptation of the canine hookworm is related to its diversity and developmental dynamics. This comprehensive comparative genomic and expression study substantially improves our understanding of

  17. Advances in the application of genetic manipulation methods to apicomplexan parasites.

    Science.gov (United States)

    Suarez, C E; Bishop, R P; Alzan, H F; Poole, W A; Cooke, B M

    2017-10-01

    Apicomplexan parasites such as Babesia, Theileria, Eimeria, Cryptosporidium and Toxoplasma greatly impact animal health globally, and improved, cost-effective measures to control them are urgently required. These parasites have complex multi-stage life cycles including obligate intracellular stages. Major gaps in our understanding of the biology of these relatively poorly characterised parasites and the diseases they cause severely limit options for designing novel control methods. Here we review potentially important shared aspects of the biology of these parasites, such as cell invasion, host cell modification, and asexual and sexual reproduction, and explore the potential of the application of relatively well-established or newly emerging genetic manipulation methods, such as classical transfection or gene editing, respectively, for closing important gaps in our knowledge of the function of specific genes and proteins, and the biology of these parasites. In addition, genetic manipulation methods impact the development of novel methods of control of the diseases caused by these economically important parasites. Transient and stable transfection methods, in conjunction with whole and deep genome sequencing, were initially instrumental in improving our understanding of the molecular biology of apicomplexan parasites and paved the way for the application of the more recently developed gene editing methods. The increasingly efficient and more recently developed gene editing methods, in particular those based on the CRISPR/Cas9 system and previous conceptually similar techniques, are already contributing to additional gene function discovery using reverse genetics and related approaches. However, gene editing methods are only possible due to the increasing availability of in vitro culture, transfection, and genome sequencing and analysis techniques. We envisage that rapid progress in the development of novel gene editing techniques applied to apicomplexan parasites of

  18. A novel alternative method for 3D visualisation in Parasitology: the construction of a 3D model of a parasite from 2D illustrations.

    Science.gov (United States)

    Teo, B G; Sarinder, K K S; Lim, L H S

    2010-08-01

    Three-dimensional (3D) models of the marginal hooks, dorsal and ventral anchors, bars and haptoral reservoirs of a parasite, Sundatrema langkawiense Lim & Gibson, 2009 (Monogenea) were developed using the polygonal modelling method in Autodesk 3ds Max (Version 9) based on two-dimensional (2D) illustrations. Maxscripts were written to rotate the modelled 3D structures. Appropriately orientated 3D haptoral hard-parts were then selected and positioned within the transparent 3D outline of the haptor and grouped together to form a complete 3D haptoral entity. This technique is an inexpensive tool for constructing 3D models from 2D illustrations for 3D visualisation of the spatial relationships between the different structural parts within organisms.

  19. Parasitic diseases

    International Nuclear Information System (INIS)

    Rozenshtraukh, L.S.

    1983-01-01

    Foundations of roentgenological semiotics of parasitic diseases of lungs, w hich are of the greatest practical value, are presented. Roentgenological pictu res of the following parasitic diseases: hydatid and alveolar echinococcosis, pa ragonimiasis, toxoplasmosis, ascariasis, amebiasis, bilharziasis (Schistosomias is) of lungs, are considered

  20. Fucoidan Supplementation Improves Exercise Performance and Exhibits Anti-Fatigue Action in Mice

    Directory of Open Access Journals (Sweden)

    Yi-Ming Chen

    2014-12-01

    Full Text Available Fucoidan (FCD is a well-known bioactive constituent of seaweed extract that possess a wide spectrum of activities in biological systems, including anti-cancer, anti-inflammation and modulation of immune systems. However, evidence on the effects of FCD on exercise performance and physical fatigue is limited. Therefore, we investigated the potential beneficial effects of FCD on ergogenic and anti-fatigue functions following physiological challenge. Male ICR mice from three groups (n = 8 per group were orally administered FCD for 21 days at 0, 310 and 620 mg/kg/day, which were, respectively, designated the vehicle, FCD-1X and FCD-2X groups. The results indicated that the FCD supplementations increased the grip strength (p = 0.0002 and endurance swimming time (p = 0.0195 in a dose-depend manner. FCD treatments also produced dose-dependent decreases in serum levels of lactate (p < 0.0001 and ammonia (p = 0.0025, and also an increase in glucose level (p < 0.0001 after the 15-min swimming test. In addition, FCD supplementation had few subchronic toxic effects. Therefore, we suggest that long-term supplementation with FCD can have a wide spectrum of bioactivities on health promotion, performance improvement and anti-fatigue.

  1. Anti-N-methyl-D-aspartate receptor encephalitis associated with intracranial Angiostrongylus cantonensis infection: a case report.

    Science.gov (United States)

    Peng, Yu; Liu, Xiaojia; Pan, Suyue; Xie, Zuoshan; Wang, Honghao

    2017-04-01

    Anti-N-methyl-D-aspartate (NMDA) receptor encephalitis is a recently described paraneoplastic syndrome with prominent neuropsychiatric symptoms. Many of these cases are associated with neoplasma especially teratoma. In addition, a few of cases with anti-NMDAR antibodies triggered by viral infection have been reported, but never by parasitic infection. Here, we report a novel case of NMDA receptor encephalitis in a 51-year-old male related to the development of anti-NMDAR antibodies triggered by Angiostrongylus cantonensis infection.

  2. Effect of BMAP-28 antimicrobial peptides on Leishmania major promastigote and amastigote growth: role of leishmanolysin in parasite survival.

    Directory of Open Access Journals (Sweden)

    Miriam A Lynn

    Full Text Available Protozoan parasites, such as Leishmania, still pose an enormous public health problem in many countries throughout the world. Current measures are outdated and have some associated drug resistance, prompting the search into novel therapies. Several innovative approaches are under investigation, including the utilization of host defence peptides (HDPs as emerging anti-parasitic therapies. HDPs are characterised by their small size, amphipathic nature and cationicity, which induce permeabilization of cell membranes, whilst modulating the immune response of the host. Recently, members of the cathelicidin family of HDPs have demonstrated significant antimicrobial activities against various parasites including Leishmania. The cathelicidin bovine myeloid antimicrobial peptide 28 (BMAP-28 has broad antimicrobial activities and confers protection in animal models of bacterial infection or sepsis. We tested the effectiveness of the use of BMAP-28 and two of its isomers the D-amino acid form (D-BMAP-28 and the retro-inverso form (RI-BMAP-28, as anti-leishmanial agents against the promastigote and amastigote intracellular Leishmania major lifecycle stages.An MTS viability assay was utilized to show the potent antiparasitic activity of BMAP-28 and its protease resistant isomers against L. major promastigotes in vitro. Cell membrane permeability assays, caspase 3/7, Tunel assays and morphologic studies suggested that this was a late stage apoptotic cell death with early osmotic cell lysis caused by the antimicrobial peptides. Furthermore, BMAP-28 and its isomers demonstrated anti-leishmanial activities against intracellular amastigotes within a macrophage infection model.Interestingly, D-BMAP-28 appears to be the most potent antiparasitic of the three isomers against wild type L. major promastigotes and amastigotes. These exciting results suggest that BMAP-28 and its protease resistant isomers have significant therapeutic potential as novel anti-leishmanials.

  3. How have fisheries affected parasite communities?

    Science.gov (United States)

    Wood, Chelsea L; Lafferty, Kevin D

    2015-01-01

    To understand how fisheries affect parasites, we conducted a meta-analysis of studies that contrasted parasite assemblages in fished and unfished areas. Parasite diversity was lower in hosts from fished areas. Larger hosts had a greater abundance of parasites, suggesting that fishing might reduce the abundance of parasites by selectively removing the largest, most heavily parasitized individuals. After controlling for size, the effect of fishing on parasite abundance varied according to whether the host was fished and the parasite's life cycle. Parasites of unfished hosts were more likely to increase in abundance in response to fishing than were parasites of fished hosts, possibly due to compensatory increases in the abundance of unfished hosts. While complex life cycle parasites tended to decline in abundance in response to fishing, directly transmitted parasites tended to increase. Among complex life cycle parasites, those with fished hosts tended to decline in abundance in response to fishing, while those with unfished hosts tended to increase. However, among directly transmitted parasites, responses did not differ between parasites with and without fished hosts. This work suggests that parasite assemblages are likely to change substantially in composition in increasingly fished ecosystems, and that parasite life history and fishing status of the host are important in predicting the response of individual parasite species or groups to fishing.

  4. Viruses of parasites as actors in the parasite-host relationship: A "ménage à trois".

    Science.gov (United States)

    Gómez-Arreaza, Amaranta; Haenni, Anne-Lise; Dunia, Irene; Avilán, Luisana

    2017-02-01

    The complex parasite-host relationship involves multiple mechanisms. Moreover, parasites infected by viruses modify this relationship adding more complexity to the system that now comprises three partners. Viruses infecting parasites were described several decades ago. However, until recently little was known about the viruses involved and their impact on the resulting disease caused to the hosts. To clarify this situation, we have concentrated on parasitic diseases caused to humans and on how virus-infected parasites could alter the symptoms inflicted on the human host. It is clear that the effect caused to the human host depends on the virus and on the parasite it has infected. Consequently, the review is divided as follows: Viruses with a possible effect on the virulence of the parasite. This section reviews pertinent articles showing that infection of parasites by viruses might increase the detrimental effect of the tandem virus-parasite on the human host (hypervirulence) or decrease virulence of the parasite (hypovirulence). Parasites as vectors affecting the transmission of viruses. In some cases, the virus-infected parasite might facilitate the transfer of the virus to the human host. Parasites harboring viruses with unidentified effects on their host. In spite of recently renewed interest in parasites in connection with their viruses, there still remains a number of cases in which the effect of the virus of a given parasite on the human host remains ambiguous. The triangular relationship between the virus, the parasite and the host, and the modulation of the pathogenicity and virulence of the parasites by viruses should be taken into account in the rationale of fighting against parasites. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Factors contributing to delay in parasite clearance in uncomplicated falciparum malaria in children

    Directory of Open Access Journals (Sweden)

    Sijuade Abayomi

    2010-02-01

    Full Text Available Abstract Background Drug resistance in Plasmodium falciparum is common in many endemic and other settings but there is no clear recommendation on when to change therapy when there is delay in parasite clearance after initiation of therapy in African children. Methods The factors contributing to delay in parasite clearance, defined as a clearance time > 2 d, in falciparum malaria were characterized in 2,752 prospectively studied children treated with anti-malarial drugs between 1996 and 2008. Results 1,237 of 2,752 children (45% had delay in parasite clearance. Overall 211 children (17% with delay in clearance subsequently failed therapy and they constituted 72% of those who had drug failure, i.e., 211 of 291 children. The following were independent risk factors for delay in parasite clearance at enrolment: age less than or equal to 2 years (Adjusted odds ratio [AOR] = 2.13, 95% confidence interval [CI]1.44-3.15, P 50,000/ul (AOR = 2.21, 95% CI = 1.77-2.75, P 20000/μl a day after treatment began, were independent risk factors for delay in clearance. Non-artemisinin monotherapies were associated with delay in clearance and treatment failures, and in those treated with chloroquine or amodiaquine, with pfmdr 1/pfcrt mutants. Delay in clearance significantly increased gametocyte carriage (P Conclusion Delay in parasite clearance is multifactorial, is related to drug resistance and treatment failure in uncomplicated malaria and has implications for malaria control efforts in sub-Saharan Africa.

  6. Anti-parasitic activity of pelleted sainfoin (Onobrychis viciifolia) against Ostertagia ostertagi and Cooperia oncophora in calves

    DEFF Research Database (Denmark)

    Desrues, O.; Pena-Espinoza, Miguel Angel; Hansen, T. V.

    2016-01-01

    BACKGROUND: Increasing anthelmintic-resistance in nematodes of ruminants emphasises the need for sustainable parasite control. Condensed tannin-containing legume forages such as sainfoin (Onobrychis viciifolia) have shown promising anthelmintic properties in small ruminants but this has never been...

  7. Host and parasite morphology influence congruence between host and parasite phylogenies.

    Science.gov (United States)

    Sweet, Andrew D; Bush, Sarah E; Gustafsson, Daniel R; Allen, Julie M; DiBlasi, Emily; Skeen, Heather R; Weckstein, Jason D; Johnson, Kevin P

    2018-03-23

    Comparisons of host and parasite phylogenies often show varying degrees of phylogenetic congruence. However, few studies have rigorously explored the factors driving this variation. Multiple factors such as host or parasite morphology may govern the degree of phylogenetic congruence. An ideal analysis for understanding the factors correlated with congruence would focus on a diverse host-parasite system for increased variation and statistical power. In this study, we focused on the Brueelia-complex, a diverse and widespread group of feather lice that primarily parasitise songbirds. We generated a molecular phylogeny of the lice and compared this tree with a phylogeny of their avian hosts. We also tested for the contribution of each host-parasite association to the overall congruence. The two trees overall were significantly congruent, but the contribution of individual associations to this congruence varied. To understand this variation, we developed a novel approach to test whether host, parasite or biogeographic factors were statistically associated with patterns of congruence. Both host plumage dimorphism and parasite ecomorphology were associated with patterns of congruence, whereas host body size, other plumage traits and biogeography were not. Our results lay the framework for future studies to further elucidate how these factors influence the process of host-parasite coevolution. Copyright © 2018 Australian Society for Parasitology. Published by Elsevier Ltd. All rights reserved.

  8. Parasites as prey in aquatic food webs: implications for predator infection and parasite transmission

    NARCIS (Netherlands)

    Thieltges, D.W.; Amundsen, P.-A.; Hechinger, R.F.; Johnson, P.T.J.; Lafferty, K.D.; Mouritsen, K.N.; Preston, D.L.; Reise, K.; Zander, C.D.; Poulin, R.

    2013-01-01

    While the recent inclusion of parasites into food-web studies has highlighted the role of parasites as consumers, there is accumulating evidence that parasites can also serve as prey for predators. Here we investigated empirical patterns of predation on parasites and their relationships with

  9. On the analysis of parasite effect for Aedes aegypti and Aedes albopictus population

    Science.gov (United States)

    Kallista, Meta; Aldila, Dipo; Nuraini, Nuning; Soewono, Edy

    2014-03-01

    It has been reported in some countries that the population of Aedes aegypti has been significantly reduced by the invasion of Aedes albopictus. There has been a hypothesis explaining this phenomenon of which investigated the influence of parasites pathogenesis to the competition between these two mosquito species in the fields. Ascogregarina taiwanensis and Ascogregarina culicis are known as parasites that infect Aedes albopictus and Aedes aegypti, respectively. Several studies have concluded that Ascogregarina taiwanensis caused high fatality for Aedes aegypti larvae, but Ascogregarina culicis was not pathogenic to Aedes albopictus larvae. Therefore, Ascogregarina taiwanensis may contribute to reduce the number of populations Aedes aegypti in the fields. Inspired by these facts, a mathematical model depicting interaction between parasites and mosquitoes is constructed in this paper. In this model are included six dynamic mosquito compartments, i.e. egg, larvae, infected larvae, adult, infected adult and one dynamic compartment for parasite. Derivation of the existence criteria and the stability analysis of parasite-free equilibrium as well as the basic offspring for the model are presented. Numerical simulations for sensitivity analysis indicating the invasive species for variation parameters are shown.

  10. Improved performance of mesostructured perovskite solar cells via an anti-solvent method

    Science.gov (United States)

    Hao, Jiabin; Hao, Huiying; Cheng, Feiyu; Li, Jianfeng; Zhang, Haiyu; Dong, Jingjing; Xing, Jie; Liu, Hao; Wu, Jian

    2018-06-01

    One-step solution process is a facile and widely used procedure to prepare organic-inorganic perovskite materials. However, the poor surface morphology of the films attributed to the uncontrollable nucleation and crystal growth in the process is unfavorable to solar cells. In this study, an anti-solvent treatment during the one-step solution process, in which ethyl acetate (EA) was dropped on the sample during spinning the precursor solution containing CH3NH3Cl, was adopted to fabricate perovskite materials and solar cells. It was found that the morphology of the perovskite film was significantly improved due to the rapid nucleation and slow crystal growth process. The modified process enabled us to fabricate the mesoporous solar cell with power conversion efficiency of 14%, showing an improvement of 40% over the efficiency of 9.7% of the device prepared by conventional one-step method. The controlling effect of annealing time on the morphology, crystal structure and transport properties of perovskite layer as well as the performance of device fabricated by the anti-solvent method were investigated and the possible mechanism was discussed.

  11. Within- and among-family variation in parasite load and parasite-induced mortality in the land snail Arianta arbustorum, a host of parasitic mites.

    Science.gov (United States)

    Schüpbach, Hans Ulrich; Baur, Bruno

    2010-08-01

    Variation in host susceptibility and parasite-induced mortality are preconditions for parasite-related selection on host populations. In terrestrial gastropods, variation in resistance against ectoparasite infection is poorly understood. We examined the within- and among-family variation in parasite load in full-siblings of the land snail Arianta arbustorum experimentally infected with Riccardoella limacum , a mite living in the mantle cavity of helicid land snails. We also quantified the influence of family origin and host size on parasite load and calculated its heritability (h(2)). Furthermore, we examined the influence of parasite load, snail size, and family origin on host winter mortality, an important life-history trait of A. arbustorum . Parasite load was heritable (h(2) = 0.63). In infected snails, parasite load was affected by family origin and increased with increasing shell size. Host mortality during hibernation increased with increasing parasite load and differed among families, but was not affected by snail size. Our results show high among-family variation both in resistance against ectoparasite infection and in host winter mortality. Furthermore, we show that parasite load is linked to snail size, which suggests that the proliferation of R. limacum is limited by resources provided by A. arbustorum .

  12. Human Parasitic Diseases in Bulgaria in Between 2013-2014

    Science.gov (United States)

    Rainova, Iskra; Harizanov, Rumen; Kaftandjiev, Iskren; Tsvetkova, Nina; Mikov, Ognyan; Kaneva, Eleonora

    2018-01-01

    Background: In Bulgaria, more than 20 autochthonous human parasitic infections have been described and some of them are widespread. Over 50 imported protozoan and helminthic infections represent diagnostic and therapeutic challenges and pose epidemiological risks due to the possibility of local transmission. Aims: To establish the distribution of autochthonous and imported parasitic diseases among the population of the country over a 2-year period (2013-2014) and to evaluate their significance in the public health system. Study Design: Cross sectional study. Methods: We used the annual reports by regional health inspectorates and data from the National Reference Laboratory at the National Centre of Infectious and Parasitic Diseases on all individuals infected with parasitic diseases in the country. Prevalence was calculated for parasitic diseases with few or absent clinical manifestations (oligosymptomatic or asymptomatic infections). Incidence per 100.000 was calculated for diseases with an overt clinical picture or those that required hospitalisation and specialised medical interventions (e.g. surgery). Results: During the research period, parasitological studies were conducted on 1441.244 persons, and parasitic infections were diagnosed in 22.039 individuals. Distribution of various parasitic pathogens among the population displayed statistically significant differences in prevalence for some intestinal parasites (enterobiasis 0.81%, giardiasis 0.34% and blastocystosis 0.22%). For certain zoonotic diseases such as cystic echinococcosis (average incidence of 3.99 per 100.000) and trichinellosis (average incidence of 0.8 per 100.000), the incidence exceeds several times the annual incidence recorded in the European Union. Conclusion: Parasitic diseases still pose a substantial problem with social and medical impacts on the residents of our country. Improved efficiency regarding autochthonous and imported parasitic diseases is essential in providing the public

  13. Host-Parasite Interaction: Parasite-Derived and -Induced Proteases That Degrade Human Extracellular Matrix

    Directory of Open Access Journals (Sweden)

    Carolina Piña-Vázquez

    2012-01-01

    Full Text Available Parasitic protozoa are among the most important pathogens worldwide. Diseases such as malaria, leishmaniasis, amoebiasis, giardiasis, trichomoniasis, and trypanosomiasis affect millions of people. Humans are constantly threatened by infections caused by these pathogens. Parasites engage a plethora of surface and secreted molecules to attach to and enter mammalian cells. The secretion of lytic enzymes by parasites into host organs mediates critical interactions because of the invasion and destruction of interstitial tissues, enabling parasite migration to other sites within the hosts. Extracellular matrix is a complex, cross-linked structure that holds cells together in an organized assembly and that forms the basement membrane lining (basal lamina. The extracellular matrix represents a major barrier to parasites. Therefore, the evolution of mechanisms for connective-tissue degradation may be of great importance for parasite survival. Recent advances have been achieved in our understanding of the biochemistry and molecular biology of proteases from parasitic protozoa. The focus of this paper is to discuss the role of protozoan parasitic proteases in the degradation of host ECM proteins and the participation of these molecules as virulence factors. We divide the paper into two sections, extracellular and intracellular protozoa.

  14. [Evaluation on intervention measures of comprehensive control for parasitic diseases in demonstration plot of Xiangyun County].

    Science.gov (United States)

    Wen-Juan, Li; Shao-Rong, Chen; Yan-Hong, Li; Wen, Fang; Chun-Rong, Ke; Li-Bo, Wang

    2011-10-01

    To evaluate the effect of comprehensive intervention measures to control and prevent parasitic diseases in the demonstration plot of Xiangyun County, so as to provide the evidence for establishing appropriate measures of parasitic diseases control and prevention. The baseline data of soil-transmitted nematode infections were obtained in 2006. A series of intervention measures, including health education, deworming, drinking water improvement,latrine improvement, and environment reconstruction, were performed for three years and the effect of the comprehensive intervention measures was evaluated by the national expert group in 2009. The awareness rate of parasitic disease knowledge of residents in 2009 (86.96%) was significantly higher than that in 2006 (35.20%) (Chi2 = 122.95, P transmitted nematode infections, the infection rates of Ascaris lumbricoides in both 2006 and 2009 were the highest and the rates were 18.74% and 2.08%, respectively. In the demonstration plots for parasitic diseases control and prevention of Xiangyun County, the effect of the comprehensive intervention measures which take health education as the forerunner and give priority to control source of parasite infection is remarkable. The measures implemented can achieve the purpose to reduce the infection rates of parasites and improve human health.

  15. One Health: parasites and beyond.

    Science.gov (United States)

    Blake, Damer P; Betson, Martha

    2017-01-01

    The field of parasitism is broad, encompassing relationships between organisms where one benefits at the expense of another. Traditionally the discipline focuses on eukaryotes, with the study of bacteria and viruses complementary but distinct. Nonetheless, parasites vary in size and complexity from single celled protozoa, to enormous plants like those in the genus Rafflesia. Lifecycles range from obligate intracellular to extensive exoparasitism. Examples of parasites include high-profile medical and zoonotic pathogens such as Plasmodium, veterinary pathogens of wild and captive animals and many of the agents which cause neglected tropical diseases, stretching to parasites which infect plants and other parasites (e.g. Kikuchi et al. 2011; Hotez et al. 2014; Blake et al. 2015; Hemingway, 2015; Meekums et al. 2015; Sandlund et al. 2015). The breadth of parasitology has been matched by the variety of ways in which parasites are studied, drawing upon biological, chemical, molecular, epidemiological and other expertise. Despite such breadth bridging between disciplines has commonly been problematic, regardless of extensive encouragement from government agencies, peer audiences and funding bodies promoting multidisciplinary research. Now, progress in understanding and collaboration can benefit from establishment of the One Health concept (Zinsstag et al. 2012; Stark et al. 2015). One Health draws upon biological, environmental, medical, veterinary and social science disciplines in order to improve human, animal and environmental health, although it remains tantalizingly difficult to engage many relevant parties. For infectious diseases traditional divides have been exacerbated as the importance of wildlife reservoirs, climate change, food production systems and socio-economic diversity have been recognized but often not addressed in a multidisciplinary manner. In response the 2015 Autumn Symposium organized by the British Society for Parasitology (BSP; https

  16. Identifying anti-Toxocara IgG antibodies in horses of Mexico

    Directory of Open Access Journals (Sweden)

    R. Heredia

    Full Text Available ABSTRACT Both the presence of owned dogs and stray dogs allows the spread of Toxocara, a parasite whose eggs can be found in soil, water and food. Animals, including horses, serve as definitive and paratenic hosts. In México, where consumption of horse meat is common, Toxocara is a zoonotic parasite. The aim of this study was to identify the presence of anti-Toxocara antibodies in work horses and horses intended for human consumption by ELISA. ELISA was chosen for analysis as paratenic hosts do not shed Toxocara eggs in their feces. Blood samples were collected from a total of 188 horses, 94 of which were work horses and 94 horses from the slaughter house. Samples were analyzed by ELISA, and the general equine seroprevalence was found to be 44.6% (n = 188. Adult horses for slaughter had a 61.7% greater presence of anti-Toxocara antibodies (p = 0.006. Toxocara IgG antibodies were found in horses, confirming that horses are paratenic hosts and possible sources of infection for other animals and people.

  17. Lipid Bodies as Sites of Prostaglandin E2 Synthesis During Chagas Disease: Impact in the Parasite Escape Mechanism

    Directory of Open Access Journals (Sweden)

    Patrícia E. de Almeida

    2018-03-01

    Full Text Available During Chagas disease, the Trypanosoma cruzi can induce some changes in the host cells in order to escape or manipulate the host immune response. The modulation of the lipid metabolism in the host phagocytes or in the parasite itself is one feature that has been observed. The goal of this mini review is to discuss the mechanisms that regulate intracellular lipid body (LB biogenesis in the course of this parasite infection and their meaning to the pathophysiology of the disease. The interaction host–parasite induces LB (or lipid droplet formation in a Toll-like receptor 2-dependent mechanism in macrophages and is enhanced by apoptotic cell uptake. Simultaneously, there is a lipid accumulation in the parasite due to the incorporation of host fatty acids. The increase in the LB accumulation during infection is correlated with an increase in the synthesis of PGE2 within the host cells and the parasite LBs. Moreover, the treatment with fatty acid synthase inhibitor C75 or non-steroidal anti-inflammatory drugs such as NS-398 and aspirin inhibited the LB biogenesis and also induced the down modulation of the eicosanoid production and the parasite replication. These findings show that LBs are organelles up modulated during the course of infection. Furthermore, the biogenesis of the LB is involved in the lipid mediator generation by both the macrophages and the parasite triggering escape mechanisms.

  18. Effect of clinically approved HDAC inhibitors on Plasmodium, Leishmania and Schistosoma parasite growth.

    Science.gov (United States)

    Chua, Ming Jang; Arnold, Megan S J; Xu, Weijun; Lancelot, Julien; Lamotte, Suzanne; Späth, Gerald F; Prina, Eric; Pierce, Raymond J; Fairlie, David P; Skinner-Adams, Tina S; Andrews, Katherine T

    2017-04-01

    Malaria, schistosomiasis and leishmaniases are among the most prevalent tropical parasitic diseases and each requires new innovative treatments. Targeting essential parasite pathways, such as those that regulate gene expression and cell cycle progression, is a key strategy for discovering new drug leads. In this study, four clinically approved anti-cancer drugs (Vorinostat, Belinostat, Panobinostat and Romidepsin) that target histone/lysine deacetylase enzymes were examined for in vitro activity against Plasmodium knowlesi, Schistosoma mansoni, Leishmania amazonensis and L. donovani parasites and two for in vivo activity in a mouse malaria model. All four compounds were potent inhibitors of P. knowlesi malaria parasites (IC 50 9-370 nM), with belinostat, panobinostat and vorinostat having 8-45 fold selectivity for the parasite over human neonatal foreskin fibroblast (NFF) or human embryonic kidney (HEK 293) cells, while romidepsin was not selective. Each of the HDAC inhibitor drugs caused hyperacetylation of P. knowlesi histone H4. None of the drugs was active against Leishmania amastigote or promastigote parasites (IC 50  > 20 μM) or S. mansoni schistosomula (IC 50  > 10 μM), however romidepsin inhibited S. mansoni adult worm parings and egg production (IC 50 ∼10 μM). Modest in vivo activity was observed in P. berghei infected mice dosed orally with vorinostat or panobinostat (25 mg/kg twice daily for four days), with a significant reduction in parasitemia observed on days 4-7 and 4-10 after infection (P < 0.05), respectively. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  19. Effect of clinically approved HDAC inhibitors on Plasmodium, Leishmania and Schistosoma parasite growth

    Directory of Open Access Journals (Sweden)

    Ming Jang Chua

    2017-04-01

    Full Text Available Malaria, schistosomiasis and leishmaniases are among the most prevalent tropical parasitic diseases and each requires new innovative treatments. Targeting essential parasite pathways, such as those that regulate gene expression and cell cycle progression, is a key strategy for discovering new drug leads. In this study, four clinically approved anti-cancer drugs (Vorinostat, Belinostat, Panobinostat and Romidepsin that target histone/lysine deacetylase enzymes were examined for in vitro activity against Plasmodium knowlesi, Schistosoma mansoni, Leishmania amazonensis and L. donovani parasites and two for in vivo activity in a mouse malaria model. All four compounds were potent inhibitors of P. knowlesi malaria parasites (IC50 9–370 nM, with belinostat, panobinostat and vorinostat having 8–45 fold selectivity for the parasite over human neonatal foreskin fibroblast (NFF or human embryonic kidney (HEK 293 cells, while romidepsin was not selective. Each of the HDAC inhibitor drugs caused hyperacetylation of P. knowlesi histone H4. None of the drugs was active against Leishmania amastigote or promastigote parasites (IC50 > 20 μM or S. mansoni schistosomula (IC50 > 10 μM, however romidepsin inhibited S. mansoni adult worm parings and egg production (IC50 ∼10 μM. Modest in vivo activity was observed in P. berghei infected mice dosed orally with vorinostat or panobinostat (25 mg/kg twice daily for four days, with a significant reduction in parasitemia observed on days 4–7 and 4–10 after infection (P < 0.05, respectively.

  20. Inevitability of Genetic Parasites

    Science.gov (United States)

    Iranzo, Jaime; Puigbò, Pere; Lobkovsky, Alexander E.; Wolf, Yuri I.

    2016-01-01

    Abstract Almost all cellular life forms are hosts to diverse genetic parasites with various levels of autonomy including plasmids, transposons and viruses. Theoretical modeling of the evolution of primordial replicators indicates that parasites (cheaters) necessarily evolve in such systems and can be kept at bay primarily via compartmentalization. Given the (near) ubiquity, abundance and diversity of genetic parasites, the question becomes pertinent: are such parasites intrinsic to life? At least in prokaryotes, the persistence of parasites is linked to the rate of horizontal gene transfer (HGT). We mathematically derive the threshold value of the minimal transfer rate required for selfish element persistence, depending on the element duplication and loss rates as well as the cost to the host. Estimation of the characteristic gene duplication, loss and transfer rates for transposons, plasmids and virus-related elements in multiple groups of diverse bacteria and archaea indicates that most of these rates are compatible with the long term persistence of parasites. Notably, a small but non-zero rate of HGT is also required for the persistence of non-parasitic genes. We hypothesize that cells cannot tune their horizontal transfer rates to be below the threshold required for parasite persistence without experiencing highly detrimental side-effects. As a lower boundary to the minimum DNA transfer rate that a cell can withstand, we consider the process of genome degradation and mutational meltdown of populations through Muller’s ratchet. A numerical assessment of this hypothesis suggests that microbial populations cannot purge parasites while escaping Muller’s ratchet. Thus, genetic parasites appear to be virtually inevitable in cellular organisms. PMID:27503291

  1. Spider silk constructs enhance axonal regeneration and remyelination in long nerve defects in sheep.

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    Christine Radtke

    Full Text Available BACKGROUND: Surgical reapposition of peripheral nerve results in some axonal regeneration and functional recovery, but the clinical outcome in long distance nerve defects is disappointing and research continues to utilize further interventional approaches to optimize functional recovery. We describe the use of nerve constructs consisting of decellularized vein grafts filled with spider silk fibers as a guiding material to bridge a 6.0 cm tibial nerve defect in adult sheep. METHODOLOGY/PRINCIPAL FINDINGS: The nerve constructs were compared to autologous nerve grafts. Regeneration was evaluated for clinical, electrophysiological and histological outcome. Electrophysiological recordings were obtained at 6 months and 10 months post surgery in each group. Ten months later, the nerves were removed and prepared for immunostaining, electrophysiological and electron microscopy. Immunostaining for sodium channel (NaV 1.6 was used to define nodes of Ranvier on regenerated axons in combination with anti-S100 and neurofilament. Anti-S100 was used to identify Schwann cells. Axons regenerated through the constructs and were myelinated indicating migration of Schwann cells into the constructs. Nodes of Ranvier between myelin segments were observed and identified by intense sodium channel (NaV 1.6 staining on the regenerated axons. There was no significant difference in electrophysiological results between control autologous experimental and construct implantation indicating that our construct are an effective alternative to autologous nerve transplantation. CONCLUSIONS/SIGNIFICANCE: This study demonstrates that spider silk enhances Schwann cell migration, axonal regrowth and remyelination including electrophysiological recovery in a long-distance peripheral nerve gap model resulting in functional recovery. This improvement in nerve regeneration could have significant clinical implications for reconstructive nerve surgery.

  2. The risk of pathogenic intestinal parasite infections in Kisii Municipality, Kenya

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    Kabiru Ephantus W

    2008-07-01

    Full Text Available Abstract Background Intestinal parasitic infections are among the most common infections worldwide. Various epidemiological studies indicate that the prevalence of intestinal parasites is high especially in developing countries, although in many of these, the environmental risk factors have not been clearly elucidated. The objective of this study was to determine the risk of pathogenic intestinal parasites infections in Kisii Municipality. Methods Random sampling was used in the selection of the study samples. Stool parasitological profiles of food handlers were done by direct smear and formalin-ethyl acetate sedimentation method. Both vegetable and meat samples were examined for the presence of intestinal parasites. The storage and meat handling practices of the various butcheries were observed. Results Types of samples examined for occurrence of intestinal parasites includes, a total of 84 vegetable, 440 meat and 168 stool samples. Fifty five (65.5% vegetable, 334 (75.9% meat and 69 (41.1% of the stool samples were found positive for intestinal parasites indicating a high overall risk (66.18% for intestinal parasite infections. Of the parasites detected, the most common parasites infesting the foodstuffs and infecting the food handlers were Ascaris lumbricoides and Entamoeba histolytica. Parasites were significantly less likely to be present on meat that was refrigerated during display than meat that was displayed at ambient temperature. Conclusion There is a high risk of infection with intestinal parasites in the sampled Municipal markets. About half of the food handlers surveyed (41.1 % at the Municipal Hospital had one or more parasitic infections. Furthermore, meat (65.5% and vegetables (75.9% sold at the Municipal market were found to be contaminated with parasites hence the inhabitants requires a need for education on food safety, good distribution practices and improvement on sanitary conditions.

  3. The "Ass" Camouflage Construction: Masks as Parasitic Heads

    Science.gov (United States)

    Levine, Robert D.

    2010-01-01

    Collins et al. 2008 offers a principles-and-parameters-based analysis of an AAVE construction first described in Spears 1998, in which nominal phrases such as "John's ass" appear to have exactly the same denotation, and behavior with respect to familiar conditions on anaphora, as the possessor ["John," and similarly for pronominal possessors.…

  4. Big Data is a powerful tool for environmental improvements in the construction business

    Science.gov (United States)

    Konikov, Aleksandr; Konikov, Gregory

    2017-10-01

    The work investigates the possibility of applying the Big Data method as a tool to implement environmental improvements in the construction business. The method is recognized as effective in analyzing big volumes of heterogeneous data. It is noted that all preconditions exist for this method to be successfully used for resolution of environmental issues in the construction business. It is proven that the principal Big Data techniques (cluster analysis, crowd sourcing, data mixing and integration) can be applied in the sphere in question. It is concluded that Big Data is a truly powerful tool to implement environmental improvements in the construction business.

  5. Occurrence of anti-Neospora caninum and anti-Toxoplasma gondii IgG antibodies in goats and sheep in western Maranhão, Brazil Ocorrência de anticorpos IgG anti-Neospora caninum e anti-Toxoplasma gondii em caprinos e ovinos do oeste do Maranhão, Brasil

    Directory of Open Access Journals (Sweden)

    Larissa Martins de Brito Moraes

    2011-12-01

    Full Text Available Neosporosis and toxoplasmosis are parasitic diseases which can cause reproductive problems in goats and sheep. The current study aimed to determine the occurrence of anti-Neospora caninum and anti-Toxoplasma gondii IgG antibodies in goats and sheep from the districts of Amarante do Maranhão and Buritirana, Imperatriz microregion, western area of Maranhão State, northeastern Brazil, and to assess factors associated to infection by these etiologic agents. Blood samples from 110 animals (46 goats and 64 sheep from five herds were collected, and indirect immunofluorescence assay was used for serological testing. Of 46 goat samples, 17.39% (n = 8 showed anti-N. caninum antibodies and 4.35% (n = 2 anti-T. gondii, while of 64 sheep samples 4.69% (n = 3 and 18.75% (n = 12 showed anti-N. caninum and anti-T. gondii antibodies, respectively. No significant difference regarding the presence of domestic cats and/or dogs on the property and veterinary care was seen for both etiologic agents studied. However, food supplementation and animal reproductive failure were significantly (p A neosporose e a toxoplasmose são doenças parasitárias que podem causar problemas reprodutivos em caprinos e ovinos. O objetivo deste estudo foi determinar a ocorrência de anticorpos IgG anti-Neospora caninum e anti-Toxoplasma gondii em caprinos e ovinos dos municípios de Amarante do Maranhão e Buritirana, microrregião de Imperatriz, Oeste maranhense, Nordeste do Brasil, bem como avaliar fatores associados à infecção por esses agentes etiológicos. Amostras de sangue de 110 animais (46 caprinos e 64 ovinos, provenientes de cinco propriedades, foram coletadas, e a reação de imunofluorescência indireta utilizada para o diagnóstico sorológico. Das 46 amostras de caprinos, 17,39% (n = 8 apresentaram anticorpos anti-N. caninum e 4,35% (n = 2 anti-T. gondii, enquanto das 64 amostras de ovinos, 4,69% (n = 3 e 18,75% (n = 12 apresentaram anticorpos anti-N. caninum e anti

  6. Evaluation of Iowa's anti-bullying law.

    Science.gov (United States)

    Ramirez, Marizen; Ten Eyck, Patrick; Peek-Asa, Corinne; Onwuachi-Willig, Angela; Cavanaugh, Joseph E

    2016-12-01

    Bullying is the most common form of youth aggression. Although 49 of all 50 states in the U.S. have an anti-bullying law in place to prevent bullying, little is known about the effectiveness of these laws. Our objective was to measure the effectiveness of Iowa's anti-bullying law in preventing bullying and improving teacher response to bullying. Sixth, 8th, and 11th grade children who completed the 2005, 2008 and 2010 Iowa Youth Survey were included in this study (n = 253,000). Students were coded according to exposure to the law: pre-law for 2005 survey data, one year post-law for 2008 data, and three years post-law for 2010 data. The outcome variables were: 1) being bullied (relational, verbal, physical, and cyber) in the last month and 2) extent to which teachers/adults on campus intervened with bullying. Generalized linear mixed models were constructed with random effects. The odds of being bullied increased from pre-law to one year post-law periods, and then decreased from one year to three years post-law but not below 2005 pre-law levels. This pattern was consistent across all bullying types except cyberbullying. The odds of teacher intervention decreased 11 % (OR = 0.89, 95 % CL = 0.88, 0.90) from 2005 (pre-law) to 2010 (post-law). Bullying increased immediately after Iowa's anti-bullying law was passed, possibly due to improved reporting. Reductions in bullying occurred as the law matured. Teacher response did not improve after the passage of the law.

  7. Northeast India Helminth Parasite Information Database (NEIHPID: Knowledge Base for Helminth Parasites.

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    Devendra Kumar Biswal

    Full Text Available Most metazoan parasites that invade vertebrate hosts belong to three phyla: Platyhelminthes, Nematoda and Acanthocephala. Many of the parasitic members of these phyla are collectively known as helminths and are causative agents of many debilitating, deforming and lethal diseases of humans and animals. The North-East India Helminth Parasite Information Database (NEIHPID project aimed to document and characterise the spectrum of helminth parasites in the north-eastern region of India, providing host, geographical distribution, diagnostic characters and image data. The morphology-based taxonomic data are supplemented with information on DNA sequences of nuclear, ribosomal and mitochondrial gene marker regions that aid in parasite identification. In addition, the database contains raw next generation sequencing (NGS data for 3 foodborne trematode parasites, with more to follow. The database will also provide study material for students interested in parasite biology. Users can search the database at various taxonomic levels (phylum, class, order, superfamily, family, genus, and species, or by host, habitat and geographical location. Specimen collection locations are noted as co-ordinates in a MySQL database and can be viewed on Google maps, using Google Maps JavaScript API v3. The NEIHPID database has been made freely available at http://nepiac.nehu.ac.in/index.php.

  8. Northeast India Helminth Parasite Information Database (NEIHPID): Knowledge Base for Helminth Parasites.

    Science.gov (United States)

    Biswal, Devendra Kumar; Debnath, Manish; Kharumnuid, Graciously; Thongnibah, Welfrank; Tandon, Veena

    2016-01-01

    Most metazoan parasites that invade vertebrate hosts belong to three phyla: Platyhelminthes, Nematoda and Acanthocephala. Many of the parasitic members of these phyla are collectively known as helminths and are causative agents of many debilitating, deforming and lethal diseases of humans and animals. The North-East India Helminth Parasite Information Database (NEIHPID) project aimed to document and characterise the spectrum of helminth parasites in the north-eastern region of India, providing host, geographical distribution, diagnostic characters and image data. The morphology-based taxonomic data are supplemented with information on DNA sequences of nuclear, ribosomal and mitochondrial gene marker regions that aid in parasite identification. In addition, the database contains raw next generation sequencing (NGS) data for 3 foodborne trematode parasites, with more to follow. The database will also provide study material for students interested in parasite biology. Users can search the database at various taxonomic levels (phylum, class, order, superfamily, family, genus, and species), or by host, habitat and geographical location. Specimen collection locations are noted as co-ordinates in a MySQL database and can be viewed on Google maps, using Google Maps JavaScript API v3. The NEIHPID database has been made freely available at http://nepiac.nehu.ac.in/index.php.

  9. Northeast India Helminth Parasite Information Database (NEIHPID): Knowledge Base for Helminth Parasites

    Science.gov (United States)

    Debnath, Manish; Kharumnuid, Graciously; Thongnibah, Welfrank; Tandon, Veena

    2016-01-01

    Most metazoan parasites that invade vertebrate hosts belong to three phyla: Platyhelminthes, Nematoda and Acanthocephala. Many of the parasitic members of these phyla are collectively known as helminths and are causative agents of many debilitating, deforming and lethal diseases of humans and animals. The North-East India Helminth Parasite Information Database (NEIHPID) project aimed to document and characterise the spectrum of helminth parasites in the north-eastern region of India, providing host, geographical distribution, diagnostic characters and image data. The morphology-based taxonomic data are supplemented with information on DNA sequences of nuclear, ribosomal and mitochondrial gene marker regions that aid in parasite identification. In addition, the database contains raw next generation sequencing (NGS) data for 3 foodborne trematode parasites, with more to follow. The database will also provide study material for students interested in parasite biology. Users can search the database at various taxonomic levels (phylum, class, order, superfamily, family, genus, and species), or by host, habitat and geographical location. Specimen collection locations are noted as co-ordinates in a MySQL database and can be viewed on Google maps, using Google Maps JavaScript API v3. The NEIHPID database has been made freely available at http://nepiac.nehu.ac.in/index.php PMID:27285615

  10. Approaches towards DNA vaccination against a skin ciliate parasite in fish.

    Directory of Open Access Journals (Sweden)

    Louise von Gersdorff Jørgensen

    Full Text Available Rainbow trout (Oncorhynchus mykiss were immunized with plasmid DNA vaccine constructs encoding selected antigens from the parasite Ichthyophthirius multifiliis. Two immobilization antigens (I-ags and one cysteine protease were tested as genetic vaccine antigen candidates. Antigenicity was evaluated by immunostaining of transfected fish cells using I-ag specific mono- and polyclonal antibodies. I. multifiliis specific antibody production, regulation of immune-relevant genes and/or protection in terms of parasite burden or mortality was measured to evaluate the induced immune response in vaccinated fish. Apart from intramuscular injection, needle free injection and gene gun delivery were tested as alternative administration techniques. For the I-ags the complement protein fragment C3d and the termini of the viral haemorrhagic septicaemia virus glyco(Gprotein (VHSV G were tested as opsonisation and cellular localisation mediators, respectively, while the full length viral G protein was tested as molecular adjuvant. Expression of I-ags in transfected fish cells was demonstrated for several constructs and by immunohistochemistry it was possible to detect expression of a secreted form of the Iag52B in the muscle cells of injected fish. Up-regulations of mRNA coding for IgM, MHC I, MHC II and TCR β, respectively, were observed in muscle tissue at the injection site in selected trials. In the spleen up-regulations were found for IFN-γ and IL-10. The highest up-regulations were seen following co-administration of I-ag and cysteine protease plasmid constructs. This correlated with a slight elevation of an I. multifiliis specific antibody response. However, in spite of detectable antigen expression and immune reactions, none of the tested vaccination strategies provided significant protection. This might suggest an insufficiency of DNA vaccination alone to trigger protective mechanisms against I. multifiliis or that other or additional parasite antigens

  11. Motivation in Construction Innovation: Commercial Opportunities, Problem-Solving and Passion for Improvement

    Directory of Open Access Journals (Sweden)

    Fang Chang Yean

    2016-01-01

    Full Text Available This article analyses motivations for innovation in construction using the service sector adaptation of the Sectoral System of Innovation (SSI framework. Interviews and site visits were conducted with four Malaysian firms. Innovation in construction is similar to the service sector. There is evidence of technology-push, capability-push and demand-pull; capability push is the most important. Construction firms innovate to gain commercial opportunities, to solve project-related problems and to improve processes. By simplifying construction work, process innovation saves time and costs, increasing efficiency and productivity, and providing increased competitiveness. Innovation is also motivated by committed and passionate actors within construction firm.

  12. Addition of 2-(ethylamino)acetonitrile group to nitroxoline results in significantly improved anti-tumor activity in vitro and in vivo.

    Science.gov (United States)

    Mitrović, Ana; Sosič, Izidor; Kos, Špela; Tratar, Urša Lampreht; Breznik, Barbara; Kranjc, Simona; Mirković, Bojana; Gobec, Stanislav; Lah, Tamara; Serša, Gregor; Kos, Janko

    2017-08-29

    Lysosomal cysteine peptidase cathepsin B, involved in multiple processes associated with tumor progression, is validated as a target for anti-cancer therapy. Nitroxoline, a known antimicrobial agent, is a potent and selective inhibitor of cathepsin B, hence reducing tumor progression in vitro and in vivo . In order to further improve its anti-cancer properties we developed a number of derivatives using structure-based chemical synthesis. Of these, the 7-aminomethylated derivative (compound 17 ) exhibited significantly improved kinetic properties over nitroxoline, inhibiting cathepsin B endopeptidase activity selectively. In the present study, we have evaluated its anti-cancer properties. It was more effective than nitroxoline in reducing tumor cell invasion and migration, as determined in vitro on two-dimensional cell models and tumor spheroids, under either endpoint or real time conditions. Moreover, it exhibited improved action over nitroxoline in impairing tumor growth in vivo in LPB mouse fibrosarcoma tumors in C57Bl/6 mice. Taken together, the addition of a 2-(ethylamino)acetonitrile group to nitroxoline at position 7 significantly improves its pharmacological characteristics and its potential for use as an anti-cancer drug.

  13. Construction and expression of an anti-VEGFR2 Nanobody-Fc fusionbody in NS0 host cell.

    Science.gov (United States)

    Qasemi, Maryam; Behdani, Mahdi; Shokrgozar, Mohammad Ali; Molla-Kazemiha, Vahid; Mohseni-Kuchesfahani, Homa; Habibi-Anbouhi, Mahdi

    2016-07-01

    Angiogenesis is the formation of new blood vessels which is involved in migration, growth and differentiation of endothelial cells. This process regularly occurs during growth and development in children however, in adults is usually part of a disease process such as cancer. The vascular endothelial growth factor (VEGF) is a vital player in the vascular development and angiogenesis in physiological and pathological processes. Camelid's immune system has unique antibodies which are composed of only a heavy chain homodimer and the variable domain (VHH, Nanobody). Nanobodies are small, around 15 kDa and stable. In this study, we engineered and constructed a new Nanobody-Fc fusion protein (fusionbody) composed of an anti-VEGFR2 Nanobody and an Fc fragment of human IgG1 antibody. The recombinant vector was transfected into NS0 host cells. Stable producer clones were developed and the recombinant fusionbody was expressed and purified. Functional assay showed the anti-VEGFR2 fusionbody could bind to VEGFR2 on cell surface via VHH part and could mediate killing the targeted cells through direct cell death and complement-dependent cytotoxicity (CDC). Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Molecular genetic transfection of the coccidian parasite Sarcocystis neurona.

    Science.gov (United States)

    Gaji, Rajshekhar Y; Zhang, Deqing; Breathnach, Cormac C; Vaishnava, Shipra; Striepen, Boris; Howe, Daniel K

    2006-11-01

    Sarcocystis neurona is an apicomplexan parasite that is the major cause of equine protozoal myeloencephalitis (EPM). The biology of this pathogen remains poorly understood in part due to unavailability of molecular genetic tools. Hence, with an objective to develop DNA transfection capabilities for S. neurona, the 5' flanking region of the SnSAG1 gene was isolated from a genomic library and used to construct expression plasmids. In transient assays, the reporter molecules beta-galactosidase (beta-gal) and yellow fluorescent protein (YFP) could be detected in electroporated S. neurona, thereby confirming the feasibility of transgene expression in this organism. Stable transformation of S. neurona was achieved using a mutant dihydrofolate reductase thymidylate synthase (DHFR-TS) gene of Toxoplasma gondii that confers resistance to pyrimethamine. This selection system was used to create transgenic S. neurona that stably express beta-gal and YFP. As shown in this study, these transgenic clones can be useful for analyzing growth rate of parasites in vitro and for assessing drug sensitivities. More importantly, the DNA transfection methods described herein should greatly facilitate studies examining intracellular parasitism by this important coccidian pathogen.

  15. Cross-reactive anti-PfCLAG9 antibodies in the sera of asymptomatic parasite carriers of Plasmodium vivax

    Science.gov (United States)

    Costa, Joana D'Arc Neves; Zanchi, Fernando Berton; Rodrigues, Francisco Lurdevanhe da Silva; Honda, Eduardo Rezende; Katsuragawa, Tony Hiroschi; Pereira, Dhélio Batista; Taborda, Roger Lafontaine Mesquita; Tada, Mauro Shugiro; Ferreira, Ricardo de Godoi Mattos; Pereira-da-Silva, Luiz Hildebrando

    2013-01-01

    The PfCLAG9 has been extensively studied because their immunogenicity. Thereby, the gene product is important for therapeutics interventions and a potential vaccine candidate. Antibodies against synthetic peptides corresponding to selected sequences of the Plasmodium falciparum antigen PfCLAG9 were found in sera of falciparum malaria patients from Rondônia, in the Brazilian Amazon. Much higher antibody titres were found in semi-immune and immune asymptomatic parasite carriers than in subjects suffering clinical infections, corroborating original findings in Papua Guinea. However, sera of Plasmodium vivax patients from the same Amazon area, in particular from asymptomatic vivax parasite carriers, reacted strongly with the same peptides. Bioinformatic analyses revealed regions of similarity between P. falciparum Pfclag9 and the P. vivax ortholog Pvclag7. Indirect fluorescent microscopy analysis showed that antibodies against PfCLAG9 peptides elicited in BALB/c mice react with human red blood cells (RBCs) infected with both P. falciparum and P. vivax parasites. The patterns of reactivity on the surface of the parasitised RBCs are very similar. The present observations support previous findings that PfCLAG9 may be a target of protective immune responses and raises the possibility that the cross reactive antibodies to PvCLAG7 in mixed infections play a role in regulate the fate of Plasmodium mixed infections. PMID:23440122

  16. Parasitism and super parasitism of Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) on Sitotroga cerealella (Oliver) (Lepidoptera: Gelechiidae) eggs

    International Nuclear Information System (INIS)

    Moreira, Marciene D.; Torres, Jorge B.

    2009-01-01

    The parasitoid Trichogramma has been used worldwide as biological control agent due to its wide geographic distribution, high specialization and efficacy against many lepidopteran pests. Biological and behavioral traits of Trichogramma pretiosum Riley parasitizing Sitotroga cerealella (Oliver) eggs were studied aiming to a better understanding of the Results from parasitism and super parasitism. The variables investigated were: host acceptance and contact time by T. pretiosum on parasitized host, percentage of parasitoid emergence, number of deformed individuals produced, egg-adult period, sex ratio, offspring female body size and longevity, and number of S. cerealella eggs parasitized/female. Parasitism rejection was observed on parasitized host eggs after 24, 72 and 120h of parasitism. The rejection was higher for eggs parasitized after 72h and 120h of parasitism as compared to the eggs after 24h of parasitism. T. pretiosum contact time on eggs after 24h of parasitism was greater than on 72 and 120h. The offspring produced from hosts from which a single parasitoid emerged were larger, exhibited no deformities and greater capacity of parasitism, different from those produced from eggs where two parasitoids emerged. Offspring longevity, however, was similar for females emerged from hosts from which one or two adults emerged. In Conclusion, T. pretiosum was able to recognize previously parasitized eggs and the super parasitism reduced the parasitoid.reproductive success. (author)

  17. Improvements in SMR Modular Construction through Supply Chain Optimization and Lessons Learned

    Energy Technology Data Exchange (ETDEWEB)

    White III, Chelsea C. [Georgia Tech Research Corporation, Atlanta, GA (United States); Petrovic, Bojan [Georgia Tech Research Corporation, Atlanta, GA (United States)

    2017-03-30

    Affordable energy is a critical societal need. Capital construction cost is a significant portion of nuclear energy cost. By controlling and reducing cost, companies can build more competitive nuclear power plants and hence provide access to more affordable energy. Modular construction provides an opportunity to reduce the cost of construction, and as projects scale up in number, the cost of each unit can be further reduced. The objective of this project was to advance design and construction methods for manufacturing Small Modular Reactors (SMRs), and in particular to improve modular construction techniques and develop best practices for designing and operating supply chains that take advantage of these techniques. The overarching objectives were to accelerate the construction schedule and reduce its variability, reduce the cost of construction, reduce interest costs accrued during construction (IDC), and thus enhance the economic attractiveness of SMRs. Our fundamental measure of merit was total capital investment cost (TCIC). To achieve these objectives, this project developed a decision support system, EVAL, to support identifying, addressing, and resolving or ameliorating challenges and deficiencies in the current modular construction approach. The results of this effort were consistent with the facts that the cost of a construction activity is often smallest when accomplished in the factory, greatest when accomplished at the construction site, and at an intermediate level when accomplished at an assembly area close to the construction site. Further, EVAL can aid in providing insight into ways to reduce waste, improve quality, efficiency, and throughput and reflects the fact that the more done early in the construction process, i.e., in the factory, the more upfront funding is required and hence the more IDC will be accrued. The analysis has lead to a better understanding of circumstances under which modular construction performed mainly in the factory will

  18. An updated review on the parasitic herb of Cuscuta reflexa Roxb.

    Science.gov (United States)

    Patel, Satish; Sharma, Vikas; Chauhan, Nagendra S; Dixit, Vinod K

    2012-03-01

    Cuscuta reflexa Roxb. is a golden yellow, leafless, perennial, parasitic herb of the family Convolvulaceae. C. reflexa has been investigated for antispasmodic, hemodynamic, anticonvulsant, anti steroidogenic, antihypertensive, muscle relaxant, cardiotonic, antiviral, antibacterial, antioxidant, cholinergic, diuretic and hair growth activities. Many chemical constituents have been isolated from C. reflexa such as cuscutin, amarbelin, β-sitosterol, stigmasterol, kaempferol, dulcitol, myricetin, quercetin, coumarin and oleanolic acid. This review presents a detailed survey of the literature on pharmacognosy, phytochemistry and traditional and biological medicinal uses of C. reflexa.

  19. Recommendations for Constructing Roadside Vegetation Barriers to Improve Near-Road Air Quality

    Science.gov (United States)

    The EPA report, Recommendations for Constructing Roadside Vegetation Barriers to Improve Near-Road Air Quality, summarizes the research findings on the best practices for building roadside vegetative barriers to improve air quality. This fact sheet describ

  20. Prevalence of Intestinal Parasitic Infection among Food Handlers in Northwest Iran

    Directory of Open Access Journals (Sweden)

    Davoud Balarak

    2016-01-01

    Full Text Available Parasitic diseases are among the most important infectious diseases and pose health problems in many countries, most especially in developing countries. Workers at food centers could transmit parasitic infections in the absence of sanitation. This is a descriptive study conducted to determine the prevalence of intestinal parasitic infections in food clerks in the city of Tabriz in 2014. Data was recorded in the offices of the health center for all food handlers who were referred to the laboratory for demographic and stool tests to receive the health card. Parasitic infection was observed in 172 cases (3.73% of 4612 samples. A total of 156 positive samples (90.69% were related to protozoa and 16 (9.3% were related to helminthes. Most of the parasitic infections were related to Giardia and Entamoeba coli and the lowest infection was related to H. nana. Also, there was a significant relationship between level of education and parasitic infection rate (P=0.0044. But there was no significant difference between the type of infection and amount of intestinal parasites. The results show that the prevalence of intestinal parasites, especially pathogenic protozoa, is common in some food handlers. Therefore, more sanitary controls are required and increasing of education will play a crucial role in improving the health of these people.

  1. Fish parasites

    DEFF Research Database (Denmark)

    This book contains 22 chapters on some of the most important parasitic diseases in wild and farmed fish. International experts give updated reviews and provide solutions to the problems......This book contains 22 chapters on some of the most important parasitic diseases in wild and farmed fish. International experts give updated reviews and provide solutions to the problems...

  2. Malaria parasites: the great escape

    Directory of Open Access Journals (Sweden)

    Laurent Rénia

    2016-11-01

    Full Text Available Parasites of the genus Plasmodium have a complex life cycle. They alternate between their final mosquito host and their intermediate hosts. The parasite can be either extra- or intracellular, depending on the stage of development. By modifying their shape, motility, and metabolic requirements, the parasite adapts to the different environments in their different hosts. The parasite has evolved to escape the multiple immune mechanisms in the host that try to block parasite development at the different stages of their development. In this article, we describe the mechanisms reported thus far that allow the Plasmodium parasite to evade innate and adaptive immune responses.

  3. IMPROVING TRADITIONAL BUILDING REPAIR CONSTRUCTION QUALITY USING HISTORIC BUILDING INFORMATION MODELING CONCEPT

    Directory of Open Access Journals (Sweden)

    T. C. Wu

    2013-07-01

    Full Text Available In addition to the repair construction project following the repair principles contemplated by heritage experts, the construction process should be recorded and measured at any time for monitoring to ensure the quality of repair. The conventional construction record methods mostly depend on the localized shooting of 2D digital images coupled with text and table for illustration to achieve the purpose of monitoring. Such methods cannot fully and comprehensively record the 3D spatial relationships in the real world. Therefore, the construction records of traditional buildings are very important but cannot function due to technical limitations. This study applied the 3D laser scanning technology to establish a 3D point cloud model for the repair construction of historical buildings. It also broke down the detailed components of the 3D point cloud model by using the concept of the historic building information modeling, and established the 3D models of various components and their attribute data in the 3DGIS platform database. In the construction process, according to the time of completion of each stage as developed on the construction project, this study conducted the 3D laser scanning and database establishment for each stage, also applied 3DGIS spatial information and attribute information comparison and analysis to propose the analysis of differences in completion of various stages for improving the traditional building repair construction quality. This method helps to improve the quality of repair construction work of tangible cultural assets of the world. The established 3DGIS platform can be used as a power tool for subsequent management and maintenance.

  4. Chimpanzee malaria parasites related to Plasmodium ovale in Africa.

    Directory of Open Access Journals (Sweden)

    Linda Duval

    Full Text Available Since the 1970's, the diversity of Plasmodium parasites in African great apes has been neglected. Surprisingly, P. reichenowi, a chimpanzee parasite, is the only such parasite to have been molecularly characterized. This parasite is closely phylogenetically related to P. falciparum, the principal cause of the greatest malaria burden in humans. Studies of malaria parasites from anthropoid primates may provide relevant phylogenetic information, improving our understanding of the origin and evolutionary history of human malaria species. In this study, we screened 130 DNA samples from chimpanzees (Pan troglodytes and gorillas (Gorilla gorilla from Cameroon for Plasmodium infection, using cytochrome b molecular tools. Two chimpanzees from the subspecies Pan t. troglodytes presented single infections with Plasmodium strains molecularly related to the human malaria parasite P. ovale. These chimpanzee parasites and 13 human strains of P. ovale originated from a various sites in Africa and Asia were characterized using cytochrome b and cytochrome c oxidase 1 mitochondrial partial genes and nuclear ldh partial gene. Consistent with previous findings, two genetically distinct types of P. ovale, classical and variant, were observed in the human population from a variety of geographical locations. One chimpanzee Plasmodium strain was genetically identical, on all three markers tested, to variant P. ovale type. The other chimpanzee Plasmodium strain was different from P. ovale strains isolated from humans. This study provides the first evidence of possibility of natural cross-species exchange of P. ovale between humans and chimpanzees of the subspecies Pan t. troglodytes.

  5. Improvement of Anti-TNF-α Antibody-Induced Palmoplantar Pustular Psoriasis Using a 308-nm Excimer Light

    Directory of Open Access Journals (Sweden)

    Natsuko Iga

    2012-11-01

    Full Text Available Anti-tumor necrosis factor (TNF-α antibody is utilized in the treatment of a variety of chronic inflammatory conditions, including psoriasis. However, it can induce paradoxical development and/or exacerbation of psoriasis in the course of anti-TNF-α antibody treatment, which is sometimes refractory to conventional treatments. Herein, we report a case of refractory palmoplantar pustular psoriasis induced by anti-TNF-α antibody treatment, which was improved by treatment with a 308-nm excimer light. The 308-nm excimer light has less long-term risks than narrow-band UVB. The 308-nm excimer light may be a good therapeutic option for refractory psoriatic skin lesions induced by anti-TNF-α antibody therapy because of localized side effects without systemic problems, short length of treatment and low cumulative dosages of UV light.

  6. Paleoparasitology: the origin of human parasites

    Directory of Open Access Journals (Sweden)

    Adauto Araujo

    2013-09-01

    Full Text Available Parasitism is composed by three subsystems: the parasite, the host, and the environment. There are no organisms that cannot be parasitized. The relationship between a parasite and its host species most of the time do not result in damage or disease to the host. However, in a parasitic disease the presence of a given parasite is always necessary, at least in a given moment of the infection. Some parasite species that infect humans were inherited from pre-hominids, and were shared with other phylogenetically close host species, but other parasite species were acquired from the environment as humans evolved. Human migration spread inherited parasites throughout the globe. To recover and trace the origin and evolution of infectious diseases, paleoparasitology was created. Paleoparasitology is the study of parasites in ancient material, which provided new information on the evolution, paleoepidemiology, ecology and phylogenetics of infectious diseases.

  7. Protein moonlighting in parasitic protists.

    Science.gov (United States)

    Ginger, Michael L

    2014-12-01

    Reductive evolution during the adaptation to obligate parasitism and expansions of gene families encoding virulence factors are characteristics evident to greater or lesser degrees in all parasitic protists studied to date. Large evolutionary distances separate many parasitic protists from the yeast and animal models upon which classic views of eukaryotic biochemistry are often based. Thus a combination of evolutionary divergence, niche adaptation and reductive evolution means the biochemistry of parasitic protists is often very different from their hosts and to other eukaryotes generally, making parasites intriguing subjects for those interested in the phenomenon of moonlighting proteins. In common with other organisms, the contribution of protein moonlighting to parasite biology is only just emerging, and it is not without controversy. Here, an overview of recently identified moonlighting proteins in parasitic protists is provided, together with discussion of some of the controversies.

  8. Ex Vivo Host and Parasite Response to Antileishmanial Drugs and Immunomodulators

    Science.gov (United States)

    McMahon-Pratt, Diane; Saravia, Nancy Gore

    2015-01-01

    Background Therapeutic response in infectious disease involves host as well as microbial determinants. Because the immune and inflammatory response to Leishmania (Viannia) species defines the outcome of infection and efficacy of treatment, immunomodulation is considered a promising therapeutic strategy. However, since Leishmania infection and antileishmanial drugs can themselves modulate drug transport, metabolism and/or immune responses, immunotherapeutic approaches require integrated assessment of host and parasite responses. Methodology To achieve an integrated assessment of current and innovative therapeutic strategies, we determined host and parasite responses to miltefosine and meglumine antimoniate alone and in combination with pentoxifylline or CpG 2006 in peripheral blood mononuclear cells (PBMCs) of cutaneous leishmaniasis patients. Parasite survival and secretion of TNF-α, IFN-γ, IL-10 and IL-13 were evaluated concomitantly in PBMCs infected with Luc-L. (V.) panamensis exposed to meglumine antimoniate (4, 8, 16, 32 and 64 μg SbV/mL) or miltefosine (2, 4, 8, 16 and 32 μM HePC). Concentrations of 4 μM of miltefosine and 8 μg SbV/mL were selected for evaluation in combination with immunomodulators based on the high but partial reduction of parasite burden by these antileishmanial concentrations without affecting cytokine secretion of infected PBMCs. Intracellular parasite survival was determined by luminometry and cytokine secretion measured by ELISA and multiplex assays. Principal Findings Anti- and pro-inflammatory cytokines characteristic of L. (V.) panamensis infection were evaluable concomitantly with viability of Leishmania within monocyte-derived macrophages present in PBMC cultures. Both antileishmanial drugs reduced the parasite load of macrophages; miltefosine also suppressed IL-10 and IL-13 secretion in a dose dependent manner. Pentoxifylline did not affect parasite survival or alter antileishmanial effects of miltefosine or meglumine

  9. Dynamics of Parascaris and Strongylus spp. parasites in untreated juvenile horses.

    Science.gov (United States)

    Fabiani, J V; Lyons, E T; Nielsen, M K

    2016-10-30

    Parasite control in foals is of utmost importance due to the high susceptibility to parasitic infection and disease in this age group. Foals are commonly co-infected with strongyle and ascarid parasites, which complicate parasite control strategies. The present study retrospectively investigated necropsy records of foals born into a university herd kept without anthelmintic treatment since 1979. The aims were to statistically analyze the relationship between fecal egg counts, worm burdens, foal age, sex, and season with specific focus on Parascaris and Strongylus spp. A total of 83 foals born between 1999 and 2015 were included. Foals were born between January and September within the given year and age at necropsy ranged between 27 and 563 days of age with a mean and median of 202 and 204 days, respectively. One set of multivariate mixed linear models was constructed analyzing strongyle and ascarid fecal egg counts as outcome variables, and another set of analyses investigated the following worm counts as outcome variables: Intestinal Parascaris spp. counts (immatures and adults), S. vulgaris (migrating and intestinal stages), S. edentatus (migrating and intestinal stages). Both ascarid and strongyle egg counts were influenced significantly by differences between study years (pvulgaris larvae were not statistically associated with any of the investigated covariates. This study provides novel information on the dynamics of important parasites in naturally infected foals. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. What do we miss? ASAS non-responders on anti-TNF therapy show improvement in performance-based physical function

    NARCIS (Netherlands)

    van Weely, S.F.E.; van Denderen, J.C.; Steultjens, M.P.M.; Nurmohamed, M.T.; Dijkmans, B.A.C.; Dekker, J.; van der Horst-Bruinsma, I.E.

    2013-01-01

    Objective: A prospective study was conducted in order to establish whether AS patients, who are defined as non-responders after 3 months of anti-TNF therapy, show improvement on performance-based tests of physical functioning. Methods: At baseline and 3 months after the start of anti-TNF therapy, AS

  11. The political construction of the nuclear energy issue and its impact on the mobilization of anti-nuclear movements in Western Europe

    International Nuclear Information System (INIS)

    Koopmans, R.; Duyvendak, J.W.

    1994-01-01

    This paper investigates the relation between objective conditions and grievances on the one hand, and the construction of the nuclear energy 'problem' and the mobilization of anti-nuclear movements in Western Europe, on the other. Using data on protest reactions to the Chernobyl disaster in Germany, France, the Netherlands, and Switzerland, we first discuss the effects of so-called 'suddenly imposed grievances'. We then turn to the frame alignment model, which emphasizes the importance of processes of definition and interpretation for the mobilization of social movements, and confront this model with data on public attitudes towards nuclear energy and anti-nuclear movement mobilization in Western Europe. Our analysis indicates that objective conditions as such have little explanatory power, and that similar events and conditions have led to widely diverging interpretations and levels of anti-nuclear mobilization in different countries. We find that the differential success of the interpretative efforts of anti-nuclear movements does neither depend on the nature of the discursive struggle itself, nor on the evidential base for the anti-nuclear movement's claims. Our data show that the movements' political opportunities, and the resulting cross-national variations in the degree to which anti-nuclear movements have been able to block or slow down the expansion of nuclear energy, have been crucial determinants both of the movements' impacts on public opinion, and of the movements' levels of mobilization. We therefore conclude that a combination of the political opportunity and framing perspectives is most fruitful in making sense of the differential careers of the nuclear energy conflict in Western Europe. (orig.) [de

  12. [Current situation of human resources of parasitic disease control and prevention organizations in Henan Province].

    Science.gov (United States)

    Ya-Lan, Zhang; Yan-Kun, Zhu; Wei-Qi, Chen; Yan, Deng; Peng, Li

    2018-01-10

    To understand the current status of human resources of parasitic disease control and prevention organizations in Henan Province, so as to provide the reference for promoting the integrative ability of the prevention and control of parasitic diseases in Henan Province. The questionnaires were designed and the method of census was adopted. The information, such as the amounts, majors, education background, technical titles, working years, and turnover in each parasitic disease control and prevention organization was collected by the centers for disease control and prevention (CDCs) at all levels. The data were descriptively analyzed. Totally 179 CDCs were investigated, in which only 19.0% (34/179) had the independent parasitic diseases control institution (department) . There were only 258 full-time staffs working on parasitic disease control and prevention in the whole province, in which only 61.9% (159/258) were health professionals. Those with junior college degree or below in the health professionals accounted for 60.3% (96/159) . Most of them (42.1%) had over 20 years of experience, but 57.9% (92/159) of their technical post titles were at primary level or below. The proportion of the health professionals is low in the parasitic disease control and prevention organizations in Henan Province. The human resource construction for parasitic disease control and prevention at all levels should be strengthened.

  13. Role of parasites in cancer.

    Science.gov (United States)

    Mandong, B M; Ngbea, J A; Raymond, Vhriterhire

    2013-01-01

    In areas of parasitic endemicity, the occurrence of cancer that is not frequent may be linked with parasitic infection. Epidemiological correlates between some parasitic infections and cancer is strong, suggesting a strong aetiological association. The common parasites associated with human cancers are schistosomiasis, malaria, liver flukes (Clonorchis sinenses, Opistorchis viverrini). To review the pathology, literature and methods of diagnosis. Literature review from peer reviewed Journals cited in PubMed and local journals. Parasites may serve as promoters of cancer in endemic areas of infection.

  14. Parasite Removal, but Not Herbivory, Deters Future Parasite Attachment on Tomato

    Science.gov (United States)

    Tjiurutue, Muvari Connie; Palmer-Young, Evan C.; Adler, Lynn S.

    2016-01-01

    Plants face many antagonistic interactions that occur sequentially. Often, plants employ defense strategies in response to the initial damage that are highly specific and can affect interactions with subsequent antagonists. In addition to herbivores and pathogens, plants face attacks by parasitic plants, but we know little about how prior herbivory compared to prior parasite attachment affects subsequent host interactions. If host plants can respond adaptively to these different damage types, we predict that prior parasitism would have a greater deterrent effect on subsequent parasites than would prior herbivory. To test the effects of prior parasitism and prior herbivory on subsequent parasitic dodder (Cuscuta spp.) preference, we conducted two separate greenhouse studies with tomato hosts (Solanum lycopersicum). In the first experiment, we tested the effects of previous dodder attachment on subsequent dodder preference on tomato hosts using three treatments: control plants that had no previous dodder attachment; dodder-removed plants that had an initial dodder seedling attached, removed and left in the same pot to simulate parasite death; and dodder-continuous plants with an initial dodder seedling that remained attached. In the second experiment, we tested the effects of previous caterpillar damage (Spodoptera exigua) and mechanical damage on future dodder attachment on tomato hosts. Dodder attached most slowly to tomato hosts that had dodder plants previously attached and then removed, compared to control plants or plants with continuous dodder attachment. In contrast, herbivory did not affect subsequent dodder attachment rate. These results indicate that dodder preference depended on the identity and the outcome of the initial attack, suggesting that early-season interactions have the potential for profound impacts on subsequent community dynamics. PMID:27529694

  15. Parasite Removal, but Not Herbivory, Deters Future Parasite Attachment on Tomato.

    Directory of Open Access Journals (Sweden)

    Muvari Connie Tjiurutue

    Full Text Available Plants face many antagonistic interactions that occur sequentially. Often, plants employ defense strategies in response to the initial damage that are highly specific and can affect interactions with subsequent antagonists. In addition to herbivores and pathogens, plants face attacks by parasitic plants, but we know little about how prior herbivory compared to prior parasite attachment affects subsequent host interactions. If host plants can respond adaptively to these different damage types, we predict that prior parasitism would have a greater deterrent effect on subsequent parasites than would prior herbivory. To test the effects of prior parasitism and prior herbivory on subsequent parasitic dodder (Cuscuta spp. preference, we conducted two separate greenhouse studies with tomato hosts (Solanum lycopersicum. In the first experiment, we tested the effects of previous dodder attachment on subsequent dodder preference on tomato hosts using three treatments: control plants that had no previous dodder attachment; dodder-removed plants that had an initial dodder seedling attached, removed and left in the same pot to simulate parasite death; and dodder-continuous plants with an initial dodder seedling that remained attached. In the second experiment, we tested the effects of previous caterpillar damage (Spodoptera exigua and mechanical damage on future dodder attachment on tomato hosts. Dodder attached most slowly to tomato hosts that had dodder plants previously attached and then removed, compared to control plants or plants with continuous dodder attachment. In contrast, herbivory did not affect subsequent dodder attachment rate. These results indicate that dodder preference depended on the identity and the outcome of the initial attack, suggesting that early-season interactions have the potential for profound impacts on subsequent community dynamics.

  16. Parasitism and the biodiversity-functioning relationship

    Science.gov (United States)

    Frainer, André; McKie, Brendan G.; Amundsen, Per-Arne; Knudsen, Rune; Lafferty, Kevin D.

    2018-01-01

    Biodiversity affects ecosystem functioning.Biodiversity may decrease or increase parasitism.Parasites impair individual hosts and affect their role in the ecosystem.Parasitism, in common with competition, facilitation, and predation, could regulate BD-EF relationships.Parasitism affects host phenotypes, including changes to host morphology, behavior, and physiology, which might increase intra- and interspecific functional diversity.The effects of parasitism on host abundance and phenotypes, and on interactions between hosts and the remaining community, all have potential to alter community structure and BD-EF relationships.Global change could facilitate the spread of invasive parasites, and alter the existing dynamics between parasites, communities, and ecosystems.Species interactions can influence ecosystem functioning by enhancing or suppressing the activities of species that drive ecosystem processes, or by causing changes in biodiversity. However, one important class of species interactions – parasitism – has been little considered in biodiversity and ecosystem functioning (BD-EF) research. Parasites might increase or decrease ecosystem processes by reducing host abundance. Parasites could also increase trait diversity by suppressing dominant species or by increasing within-host trait diversity. These different mechanisms by which parasites might affect ecosystem function pose challenges in predicting their net effects. Nonetheless, given the ubiquity of parasites, we propose that parasite–host interactions should be incorporated into the BD-EF framework.

  17. How Many Parasites Species a Frog Might Have? Determinants of Parasite Diversity in South American Anurans.

    Directory of Open Access Journals (Sweden)

    Karla Magalhães Campião

    Full Text Available There is an increasing interest in unveiling the dynamics of parasite infection. Understanding the interaction patterns, and determinants of host-parasite association contributes to filling knowledge gaps in both community and disease ecology. Despite being targeted as a relevant group for conservation efforts, determinants of the association of amphibians and their parasites in broad scales are poorly understood. Here we describe parasite biodiversity in South American amphibians, testing the influence of host body size and geographic range in helminth parasites species richness (PSR. We also test whether parasite diversity is related to hosts' phylogenetic diversity. Results showed that nematodes are the most common anuran parasites. Host-parasite network has a nested pattern, with specialist helminth taxa generally associated with hosts that harbour the richest parasite faunas. Host size is positively correlated with helminth fauna richness, but we found no support for the association of host geographic range and PSR. These results remained consistent after correcting for uneven study effort and hosts' phylogenic correlation. However, we found no association between host and parasite diversity, indicating that more diversified anuran clades not necessarily support higher parasite diversity. Overall, considering both the structure and the determinants of PRS in anurans, we conclude that specialist parasites are more likely to be associated with large anurans, which are the ones harbouring higher PSR, and that the lack of association of PSR with hosts' clade diversification suggests it is strongly influenced by ecological and contemporary constrains.

  18. (macro- Evolutionary ecology of parasite diversity: From determinants of parasite species richness to host diversification

    Directory of Open Access Journals (Sweden)

    Serge Morand

    2015-04-01

    Full Text Available The present review summarized the factors or determinants that may explain parasite diversity among host species and the consequences of this parasite diversity on the evolution of host-life history traits. As host–parasite interactions are asymmetrical exploited–exploiter relationships, ecological and epidemiological theories produce hypotheses to find the potential determinants of parasite species richness, while life-history theory helps for testing potential consequences on parasite diversity on the evolution of hosts. This review referred only to studies that have specifically controlled or took into account phylogenetic information illustrated with parasites of mammals. Several points needing more investigation were identified with a special emphasis to develop the metabolic theory of epidemiology.

  19. Pets and Parasites

    Science.gov (United States)

    ... good news is that this rarely happens. Most pet-to-people diseases can be avoided by following a few ... your doctor Can a parasite cause death in people and pets? Can human disease from a parasite be treated ...

  20. Floral Volatiles in Parasitic Plants of the Orobanchaceae. Ecological and Taxonomic Implications

    Science.gov (United States)

    Tóth, Peter; Undas, Anna K.; Verstappen, Francel; Bouwmeester, Harro

    2016-01-01

    The holoparasitic broomrapes, Orobanche spp. and Phelipanche spp. (Orobanchaceae), are root parasites that completely depend on a host plant for survival and reproduction. There is considerable controversy on the taxonomy of this biologically and agronomically important family. Flowers of over 25 parasitic Orobanchaceae and a number of close, parasitic and non-parasitic, relatives emitted a complex blend of volatile organic compounds (VOCs), consisting of over 130 VOCs per species. Floral VOC blend-based phylogeny supported the known taxonomy in internal taxonomic grouping of genus and eliminated the uncertainty in some taxonomical groups. Moreover, phylogenetic analysis suggested separation of the broomrapes into two main groups parasitizing annual and perennial hosts, and for the annual hosts, into weedy and non-weedy broomrapes. We conclude that floral VOCs are a significant tool in species identification and possibly even in defining new species and can help to improve controversial taxonomy in the Orobanchaceae. PMID:27014329

  1. Construction Project Performance Improvement through Radio Frequency Identification Technology Application on a Project Supply Chain

    Science.gov (United States)

    Wang, Heng

    2017-01-01

    Construction project productivity typically lags other industries and it has been the focus of numerous studies in order to improve the project performance. This research investigated the application of Radio Frequency Identification (RFID) technology on construction projects' supply chain and determined that RFID technology can improve the…

  2. Enlightening the malaria parasite life cycle: bioluminescent Plasmodium in fundamental and applied research

    Directory of Open Access Journals (Sweden)

    Giulia eSiciliano

    2015-05-01

    Full Text Available The unicellular protozoan parasites of the genus Plasmodium impose on human health worldwide the enormous burden of malaria. The possibility to genetically modify several species of malaria parasites represented a major advance in the possibility to elucidate their biology and is now turning laboratory lines of transgenic Plasmodium into precious weapons to fight malaria. Amongst the various genetically modified plasmodia, transgenic parasite lines expressing bioluminescent reporters have been essential to unveil mechanisms of parasite gene expression and to develop in vivo imaging approaches in mouse malaria models. Mainly the human malaria parasite Plasmodium falciparum and the rodent parasite Plasmodium berghei have been engineered to express bioluminescent reporters in almost all the developmental stages of the parasite along its complex life cycle between the insect and the vertebrate hosts. Plasmodium lines expressing conventional and improved luciferase reporters are now gaining a central role to develop cell based assays in the much needed search of new antimalarial drugs and to open innovative approaches for both fundamental and applied research in malaria.

  3. Enlightening the malaria parasite life cycle: bioluminescent Plasmodium in fundamental and applied research.

    Science.gov (United States)

    Siciliano, Giulia; Alano, Pietro

    2015-01-01

    The unicellular protozoan parasites of the genus Plasmodium impose on human health worldwide the enormous burden of malaria. The possibility to genetically modify several species of malaria parasites represented a major advance in the possibility to elucidate their biology and is now turning laboratory lines of transgenic Plasmodium into precious weapons to fight malaria. Amongst the various genetically modified plasmodia, transgenic parasite lines expressing bioluminescent reporters have been essential to unveil mechanisms of parasite gene expression and to develop in vivo imaging approaches in mouse malaria models. Mainly the human malaria parasite Plasmodium falciparum and the rodent parasite P. berghei have been engineered to express bioluminescent reporters in almost all the developmental stages of the parasite along its complex life cycle between the insect and the vertebrate hosts. Plasmodium lines expressing conventional and improved luciferase reporters are now gaining a central role to develop cell based assays in the much needed search of new antimalarial drugs and to open innovative approaches for both fundamental and applied research in malaria.

  4. A New MAP Kinase Protein Involved in Estradiol-Stimulated Reproduction of the Helminth Parasite Taenia crassiceps

    Science.gov (United States)

    Escobedo, Galileo; Soldevila, Gloria; Ortega-Pierres, Guadalupe; Chávez-Ríos, Jesús Ramsés; Nava, Karen; Fonseca-Liñán, Rocío; López-Griego, Lorena; Hallal-Calleros, Claudia; Ostoa-Saloma, Pedro; Morales-Montor, Jorge

    2010-01-01

    MAP kinases (MAPK) are involved in the regulation of cellular processes such as reproduction and growth. In parasites, the role of MAPK has been scarcely studied. Here, we describe the participation of an ERK-like protein in estrogen-dependent reproduction of the helminth parasite Taenia crassiceps. Our results show that 17β-estradiol induces a concentration-dependent increase in the bud number of in vitro cultured cysticerci. If parasites are also incubated in presence of an ERK-inhibitor, the stimulatory effect of estrogen is blocked. The expression of ERK-like mRNA and its corresponding protein was detected in the parasite. The ERK-like protein was over-expressed by all treatments. Nevertheless, a strong induction of phosphorylation of this protein was observed only in response to 17β-estradiol. Cross-contamination by host cells was discarded by flow cytometry analysis. Parasite cells expressing the ERK-like protein were exclusively located at the subtegument tissue by confocal microscopy. Finally, the ERK-like protein was separated by bidimensional electrophoresis and then sequenced, showing the conserved TEY activation motif, typical of all known ERK 1/2 proteins. Our results show that an ERK-like protein is involved in the molecular signalling during the interaction between the host and T. crassiceps, and may be considered as target for anti-helminth drugs design. PMID:20145710

  5. Protozoan Parasites in Drinking Water: A System Approach for Improved Water, Sanitation and Hygiene in Developing Countries.

    Science.gov (United States)

    Omarova, Alua; Tussupova, Kamshat; Berndtsson, Ronny; Kalishev, Marat; Sharapatova, Kulyash

    2018-03-12

    Improved water, sanitation and hygiene (WASH) are significant in preventing diarrhea morbidity and mortality caused by protozoa in low- and middle-income countries. Due to the intimate and complex relationships between the different WASH components, it is often necessary to improve not just one but all of these components to have sustainable results. The objective of this paper was to review the current state of WASH-related health problems caused by parasitic protozoa by: giving an overview and classification of protozoa and their effect on people's health, discussing different ways to improve accessibility to safe drinking water, sanitation services and personal hygiene behavior; and suggesting an institutional approach to ensure improved WASH. The findings indicate that Giardia and Cryptosporidium are more often identified during waterborne or water-washed outbreaks and they are less sensitive than most of the bacteria and viruses to conventional drinking water and wastewater treatment methods. There are various institutions of control and prevention of water-related diseases caused by protozoa in developed countries. Unfortunately, the developing regions do not have comparable systems. Consequently, the institutional and systems approach to WASH is necessary in these countries.

  6. Protozoan Parasites in Drinking Water: A System Approach for Improved Water, Sanitation and Hygiene in Developing Countries

    Science.gov (United States)

    Tussupova, Kamshat; Berndtsson, Ronny; Sharapatova, Kulyash

    2018-01-01

    Improved water, sanitation and hygiene (WASH) are significant in preventing diarrhea morbidity and mortality caused by protozoa in low- and middle-income countries. Due to the intimate and complex relationships between the different WASH components, it is often necessary to improve not just one but all of these components to have sustainable results. The objective of this paper was to review the current state of WASH-related health problems caused by parasitic protozoa by: giving an overview and classification of protozoa and their effect on people’s health, discussing different ways to improve accessibility to safe drinking water, sanitation services and personal hygiene behavior; and suggesting an institutional approach to ensure improved WASH. The findings indicate that Giardia and Cryptosporidium are more often identified during waterborne or water-washed outbreaks and they are less sensitive than most of the bacteria and viruses to conventional drinking water and wastewater treatment methods. There are various institutions of control and prevention of water-related diseases caused by protozoa in developed countries. Unfortunately, the developing regions do not have comparable systems. Consequently, the institutional and systems approach to WASH is necessary in these countries. PMID:29534511

  7. Protozoan Parasites in Drinking Water: A System Approach for Improved Water, Sanitation and Hygiene in Developing Countries

    Directory of Open Access Journals (Sweden)

    Alua Omarova

    2018-03-01

    Full Text Available Improved water, sanitation and hygiene (WASH are significant in preventing diarrhea morbidity and mortality caused by protozoa in low- and middle-income countries. Due to the intimate and complex relationships between the different WASH components, it is often necessary to improve not just one but all of these components to have sustainable results. The objective of this paper was to review the current state of WASH-related health problems caused by parasitic protozoa by: giving an overview and classification of protozoa and their effect on people’s health, discussing different ways to improve accessibility to safe drinking water, sanitation services and personal hygiene behavior; and suggesting an institutional approach to ensure improved WASH. The findings indicate that Giardia and Cryptosporidium are more often identified during waterborne or water-washed outbreaks and they are less sensitive than most of the bacteria and viruses to conventional drinking water and wastewater treatment methods. There are various institutions of control and prevention of water-related diseases caused by protozoa in developed countries. Unfortunately, the developing regions do not have comparable systems. Consequently, the institutional and systems approach to WASH is necessary in these countries.

  8. Neglected Parasitic Infections: Toxocariasis

    Centers for Disease Control (CDC) Podcasts

    2012-01-05

    This podcast is an overview of the Clinician Outreach and Communication Activity (COCA) Call: Neglected Parasitic Infections in the United States. Neglected Parasitic Infections are a group of diseases that afflict vulnerable populations and are often not well studied or diagnosed. A subject matter expert from CDC's Division of Parasitic Diseases and Malaria describes the epidemiology, diagnosis, and treatment of toxocariasis.  Created: 1/5/2012 by Center for Global Health, Division of Parasitic Diseases and Malaria (DPDM); Emergency Risk Communication Branch (ERCB)/Joint Information Center (JIC), Office of Public Health Preparedness and Response (OPHPR).   Date Released: 1/9/2012.

  9. In vitro, in silico and in vivo studies of ursolic acid as an anti-filarial agent.

    Directory of Open Access Journals (Sweden)

    Komal Kalani

    Full Text Available As part of our drug discovery program for anti-filarial agents from Indian medicinal plants, leaves of Eucalyptus tereticornis were chemically investigated, which resulted in the isolation and characterization of an anti-filarial agent, ursolic acid (UA as a major constituent. Antifilarial activity of UA against the human lymphatic filarial parasite Brugia malayi using in vitro and in vivo assays, and in silico docking search on glutathione-s-transferase (GST parasitic enzyme were carried out. The UA was lethal to microfilariae (mf; LC100: 50; IC50: 8.84 µM and female adult worms (LC100: 100; IC50: 35.36 µM as observed by motility assay; it exerted 86% inhibition in MTT reduction potential of the adult parasites. The selectivity index (SI of UA for the parasites was found safe. This was supported by the molecular docking studies, which showed adequate docking (LibDock scores for UA (-8.6 with respect to the standard antifilarial drugs, ivermectin (IVM -8.4 and diethylcarbamazine (DEC-C -4.6 on glutathione-s-transferase enzyme. Further, in silico pharmacokinetic and drug-likeness studies showed that UA possesses drug-like properties. Furthermore, UA was evaluated in vivo in B. malayi-M. coucha model (natural infection, which showed 54% macrofilaricidal activity, 56% female worm sterility and almost unchanged microfilaraemia maintained throughout observation period with no adverse effect on the host. Thus, in conclusion in vitro, in silico and in vivo results indicate that UA is a promising, inexpensive, widely available natural lead, which can be designed and developed into a macrofilaricidal drug. To the best of our knowledge this is the first ever report on the anti-filarial potential of UA from E. tereticornis, which is in full agreement with the Thomson Reuter's 'Metadrug' tool screening predictions.

  10. The most important parasites in Serbia involving the foodborne route of transmission

    Science.gov (United States)

    Petrović, J. M.; Prodanov-Radulović, J. Z.; Vasilev, S. D.

    2017-09-01

    Food can be an important route for transmission of parasites to humans. Compared to other foodborne pathogens in Serbia, foodborne (or potentially foodborne) parasites do not get the attention they undoubtedly deserve. The aim of this article is to give an overview of the most important parasitic pathogens that can be transmitted by food, and that cause disease in humans: Echinococcus, Trichinella, Taenia solium and Toxoplasma gondii. For each of these pathogens, the severity of human diseases they cause, incidence, mortality and case fatality rate among humans in Serbia as well as their prevalence in animal species in Serbia are described. Some of the described foodborne parasites can induce severe disease symptoms in humans associated with high case fatality rates, while others can cause massive outbreaks. All of the aforementioned parasites occur throughout Serbia and cause both severe public health problems and substantial economic losses in livestock production. In conclusion, the control measures of foodborne parasites certainly need to include education of farmers and improvement of veterinary sanitary measures in animal farming and animal waste control.

  11. The guanylhydrazone CNI-1493: an inhibitor with dual activity against malaria-inhibition of host cell pro-inflammatory cytokine release and parasitic deoxyhypusine synthase.

    Science.gov (United States)

    Specht, Sabine; Sarite, Salem Ramadan; Hauber, Ilona; Hauber, Joachim; Görbig, Ulf F; Meier, Chris; Bevec, Dorian; Hoerauf, Achim; Kaiser, Annette

    2008-05-01

    Malaria is still a major cause of death in the tropics. There is an urgent need for new anti-malarial drugs because drug-resistant plasmodia frequently occur. Over recent years, we elucidated the biosynthesis of hypusine, a novel amino acid contained in eukaryotic initiation factor 5A (eIF-5A) in Plasmodium. Hypusine biosynthesis involves catalysis of deoxyhypusine synthase (DHS) in the first step of post-translational modification. In a screen for new inhibitors of purified plasmodium DHS, CNI-1493, a novel selective pro-inflammatory cytokine inhibitor used in clinical phase II for the treatment of Crohn's disease, inhibited the enzyme of the parasite 3-fold at a concentration of 2 microM. In vitro experiments with 200 microM CNI-1493 in Plasmodium-infected erythrocytes, which lack nuclei and DHS protein, showed a parasite clearance within 2 days. This can presumably be attributed to an anti-proliferating effect because of the inhibition of DHS by the parasite. The determined IC50 of CNI-1493 was 135.79 microM after 72 h. In vivo application of this substance in Plasmodium berghei ANKA-infected C57BL/6 mice significantly reduced parasitemia after dosage of 1 mg/kg or 4 mg/kg/body weight and prevented death of mice with cerebral malaria. This effect was paralleled by a decrease in serum TNF levels of the mice. We suggest that the new mechanism of CNI-1493 is caused by a decrease in modified eIF-5A biosynthesis with a downstream effect on the TNF synthesis of the host. From the current data, we consider CNI-1493 to be a promising drug for anti-malarial therapy because of its combined action, i.e., the decrease in eIF-5A biosynthesis of the parasite and host cell TNF biosynthesis.

  12. Improvement of QA/QC activities in the construction of nuclear power plant

    International Nuclear Information System (INIS)

    Jinji Tomita; Shigetaka Tomaru

    1987-01-01

    Construction of commercial nuclear power plants in Japan started at around 1965. In this presentation are described quality assurance (QA) activities of a plant supplier who is a manufacturer of the key components as well. The QA activities until now are divided into several periods of the construction history in Japan. First term is 1960's when the QA activities are featured as the study and implementation through the construction of imported plants. Since then technologies and procedures of our own have been established and improved for the construction of high reliability plants. Our present QA activities are based on the active reflection of those lessons learned of past experiences. (author)

  13. The research of electrical tracing system construction management and related questions of BOP project

    International Nuclear Information System (INIS)

    Wang Lining; Li Jingmin; Ma Ding; Tu Haitao

    2015-01-01

    Based on Hongyanhe nuclear power plant in Liaoning province, the paper studies the anti-freeze and heat tracing work of BOP project. It compares several different heat tracing solutions in terms of technicality and applicability, and gave the most suitable scheme by using electrical tracing. It also presents the construction details of the electrical tracing system, analyzes the key points of the construction management from quantity, safety and schedule aspects, and gave the improvement suggestions. (authors)

  14. Innovative Approaches to Improve Anti-Infective Vaccine Efficacy.

    Science.gov (United States)

    Yeaman, Michael R; Hennessey, John P

    2017-01-06

    Safe and efficacious vaccines are arguably the most successful medical interventions of all time. Yet the ongoing discovery of new pathogens, along with emergence of antibiotic-resistant pathogens and a burgeoning population at risk of such infections, imposes unprecedented public health challenges. To meet these challenges, innovative strategies to discover and develop new or improved anti-infective vaccines are necessary. These approaches must intersect the most meaningful insights into protective immunity and advanced technologies with capabilities to deliver immunogens for optimal immune protection. This goal is considered through several recent advances in host-pathogen relationships, conceptual strides in vaccinology, and emerging technologies. Given a clear and growing risk of pandemic disease should the threat of infection go unmet, developing vaccines that optimize protective immunity against high-priority and antibiotic-resistant pathogens represents an urgent and unifying imperative.

  15. Neglected Parasitic Infections: Toxocariasis

    Centers for Disease Control (CDC) Podcasts

    This podcast is an overview of the Clinician Outreach and Communication Activity (COCA) Call: Neglected Parasitic Infections in the United States. Neglected Parasitic Infections are a group of diseases that afflict vulnerable populations and are often not well studied or diagnosed. A subject matter expert from CDC's Division of Parasitic Diseases and Malaria describes the epidemiology, diagnosis, and treatment of toxocariasis.

  16. Association of Parasite Load Levels in Amniotic Fluid With Clinical Outcome in Congenital Toxoplasmosis.

    Science.gov (United States)

    Yamamoto, Lidia; Targa, Lília S; Sumita, Laura M; Shimokawa, Paulo T; Rodrigues, Jonatas C; Kanunfre, Kelly A; Okay, Thelma S

    2017-08-01

    To correlate neonatal and infant clinical outcome with parasite load in amniotic fluid (AF). We conducted a retrospective cohort study of 122 children whose mothers had toxoplasmosis during pregnancy. The children were monitored from birth to 12 months old. Stored AF samples were obtained at maternal diagnosis and tested by quantitative polymerase chain reaction. Gestational age at maternal infection, quantitative polymerase chain reaction results, neonatal anti-Toxoplasma gondii immunoglobulin (Ig) M, and clinical outcome at 12 months were correlated. Maternal infection occurred in 18 of 122 (14.7%) and 104 of 122 (85.2%) women in the first and second trimesters, respectively. At birth, IgM was present in 107 of 122 (87.7%) neonates and 36 (29.5%) were symptomatic. Of these, half occurred in the first and the other half in the second trimester and 6 of 36 had severe infections (16.7% of symptomatic, 4.9% of total), all infected in the first trimester. Parasite load levels were highly variable (median 35 parasites/mL, range 2-30,473). Logistic regression correlated symptomatic infection with gestational age (odds ratio [OR] 0.47, CI 0.31-0.73) and parasite load (OR 2.04, CI 1.23-3.37), but not with positive IgM (OR 6.81, CI 0.86-53.9). Negative correlations were found between gestational age and parasite load (rs -0.780, CI -0.843 to -0.696), gestational age and symptoms (rs -0.664, CI -0.755 to -0.547), but not gestational age and IgM (rs -0.136, CI -0.311 to 0.048). Parasite load levels distributed by percentile showed that all symptomatic patients appeared from the 75th percentile and all severe infections from the 95th percentile. Load rankings showed doubled the OR for each 20 parasite/mL increment. Parasite load was associated with symptomatic infections (area under the curve 0.959, CI 0.908-0.987) as well as gestational age (area under the curve 0.918, CI 0.855-0.960) and both parameters combined (area under the curve 0.969, CI 0.920-0.992). Parasite load in

  17. Genome Evolution of Plant-Parasitic Nematodes.

    Science.gov (United States)

    Kikuchi, Taisei; Eves-van den Akker, Sebastian; Jones, John T

    2017-08-04

    Plant parasitism has evolved independently on at least four separate occasions in the phylum Nematoda. The application of next-generation sequencing (NGS) to plant-parasitic nematodes has allowed a wide range of genome- or transcriptome-level comparisons, and these have identified genome adaptations that enable parasitism of plants. Current genome data suggest that horizontal gene transfer, gene family expansions, evolution of new genes that mediate interactions with the host, and parasitism-specific gene regulation are important adaptations that allow nematodes to parasitize plants. Sequencing of a larger number of nematode genomes, including plant parasites that show different modes of parasitism or that have evolved in currently unsampled clades, and using free-living taxa as comparators would allow more detailed analysis and a better understanding of the organization of key genes within the genomes. This would facilitate a more complete understanding of the way in which parasitism has shaped the genomes of plant-parasitic nematodes.

  18. Improving occupational health care for construction workers: a process evaluation

    NARCIS (Netherlands)

    Boschman, Julitta S.; van der Molen, Henk F.; Sluiter, Judith K.; Frings-Dresen, Monique H. W.

    2013-01-01

    To evaluate the process of a job-specific workers' health surveillance (WHS) in improving occupational health care for construction workers. From January to July 2012 were 899 bricklayers and supervisors invited for the job-specific WHS at three locations of one occupational health service

  19. Quantitative proteomics reveals divergent responses in Apis mellifera worker and drone pupae to parasitization by Varroa destructor.

    Science.gov (United States)

    Surlis, Carla; Carolan, James C; Coffey, Mary; Kavanagh, Kevin

    Varroa destructor is a haemophagous ectoparasite of honeybees and is considered a major causal agent of colony losses in Europe and North America. Although originating in Eastern Asia where it parasitizes Apis cerana, it has shifted hosts to the western honeybee Apis mellifera on which it has a greater deleterious effect on the individual and colony level. To investigate this important host-parasite interaction and to determine whether Varroa causes different effects on different castes we conducted a label free quantitative proteomic analysis of Varroa-parasitized and non-parasitized drone and worker Apis mellifera pupae. 1195 proteins were identified in total, of which 202 and 250 were differentially abundant in parasitized drone and worker pupae, respectively. Both parasitized drone and worker pupae displayed reduced abundance in proteins associated with the cuticle, lipid transport and innate immunity. Proteins involved in metabolic processes were more abundant in both parasitized castes although the response in workers was more pronounced. A number of caste specific responses were observed including differential abundance of numerous cytoskeletal and muscle proteins, which were of higher abundance in parasitized drones in comparison to parasitized workers. Proteins involved in fatty acid and carbohydrate metabolism were more abundant in parasitized workers as were a large number of ribosomal proteins highlighting either potentially divergent responses to Varroa or a different strategy by the mite when parasitizing the different castes. This data improves our understanding of this interaction and may provide a basis for future studies into improvements to therapy and control of Varroasis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Improvement of the material and transport component of the system of construction waste management

    Science.gov (United States)

    Kostyshak, Mikhail; Lunyakov, Mikhail

    2017-10-01

    Relevance of the topic of selected research is conditioned with the growth of construction operations and growth rates of construction and demolition wastes. This article considers modern approaches to the management of turnover of construction waste, sequence of reconstruction or demolition processes of the building, information flow of the complete cycle of turnover of construction and demolition waste, methods for improvement of the material and transport component of the construction waste management system. Performed analysis showed that mechanism of management of construction waste allows to increase efficiency and environmental safety of this branch and regions.

  1. Temporal and demographic blood parasite dynamics in two free-ranging neotropical primates

    Directory of Open Access Journals (Sweden)

    Gideon A. Erkenswick

    2017-08-01

    Full Text Available Parasite-host relationships are influenced by several factors intrinsic to hosts, such as social standing, group membership, sex, and age. However, in wild populations, temporal variation in parasite distributions and concomitant infections can alter these patterns. We used microscropy and molecular methods to screen for naturally occurring haemoparasitic infections in two Neotropical primate host populations, the saddleback (Leontocebus weddelli and emperor (Saguinus imperator tamarin, in the lowland tropical rainforests of southeastern Peru. Repeat sampling was conducted from known individuals over a three-year period to test for parasite-host and parasite-parasite associations. Three parasites were detected in L. weddelli including Trypanosoma minasense, Mansonella mariae, and Dipetalonema spp., while S. imperator only hosted the latter two. Temporal variation in prevalence was observed in T. minasense and Dipetalonema spp., confirming the necessity of a multi-year study to evaluate parasite-host relationships in this system. Although callitrichids display a distinct reproductive dominance hierarchy, characterized by single breeding females that typically mate polyandrously and can suppress the reproduction of subdominant females, logistic models did not identify sex or breeding status as determining factors in the presence of these parasites. However, age class had a positive effect on infection with M. mariae and T. minasense, and adults demonstrated higher parasite species richness than juveniles or sub-adults across both species. Body weight had a positive effect on the presence of Dipetalonema spp. The inclusion of co-infection variables in statistical models of parasite presence/absence data improved model fit for two of three parasites. This study verifies the importance and need for broad spectrum and long-term screening of parasite assemblages of natural host populations.

  2. An environmental impact causal model for improving the environmental performance of construction processes

    OpenAIRE

    Fuertes Casals, Alba; Casals Casanova, Miquel; Gangolells Solanellas, Marta; Forcada Matheu, Núria; Macarulla Martí, Marcel; Roca Ramon, Xavier

    2013-01-01

    Despite the increasing efforts made by the construction sector to reduce the environmental impact of their processes, construction sites are still a major source of pollution and adverse impacts on the environment. This paper aims to improve the understanding of construction-related environmental impacts by identifying on-site causal factors and associated immediate circumstances during construc- tion processes for residential building projects. Based on the literature and focus g...

  3. Problems of improving the investing process management in NPP construction

    International Nuclear Information System (INIS)

    Denisov, G.A.

    1986-01-01

    Problems of development of the optimal system for the investing process management in NPP construction are discussed. It includes 3 steps: design construction ( including building structure and equipment production ), and achievement of designed technical and economical indices, during reactor start-up. The method for estimating the interest of each participator of the intensing process and developing the optimal solution, that is capable to approach these interests, is suggested. The conclusion is made that it is necessary to develop and confirm the branch standard, which should include a complex amalgamated network of works to improve the organization of the investing process

  4. Regulatory volume decrease in Leishmania mexicana: effect of anti-microtubule drugs

    Directory of Open Access Journals (Sweden)

    Francehuli Dagger

    2013-02-01

    Full Text Available The trypanosomatid cytoskeleton is responsible for the parasite's shape and it is modulated throughout the different stages of the parasite's life cycle. When parasites are exposed to media with reduced osmolarity, they initially swell, but subsequently undergo compensatory shrinking referred to as regulatory volume decrease (RVD. We studied the effects of anti-microtubule (Mt drugs on the proliferation of Leishmania mexicana promastigotes and their capacity to undergo RVD. All of the drugs tested exerted antiproliferative effects of varying magnitudes [ansamitocin P3 (AP3> trifluoperazine > taxol > rhizoxin > chlorpromazine]. No direct relationship was found between antiproliferative drug treatment and RVD. Similarly, Mt stability was not affected by drug treatment. Ansamitocin P3, which is effective at nanomolar concentrations, blocked amastigote-promastigote differentiation and was the only drug that impeded RVD, as measured by light dispersion. AP3 induced 2 kinetoplasts (Kt 1 nucleus cells that had numerous flagella-associated Kts throughout the cell. These results suggest that the dramatic morphological changes induced by AP3 alter the spatial organisation and directionality of the Mts that are necessary for the parasite's hypotonic stress-induced shape change, as well as its recovery.

  5. Survey of the parasite Toxoplasma gondii in human consumed ovine meat in Tunis City.

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    Sonia Boughattas

    Full Text Available Toxoplasmosis has been recognized as parasitic zoonosis with the highest human incidence. The human infection by the parasite can lead to severe clinical manifestations in congenital toxoplasmosis and immunocompromised patients. Contamination occurs mainly by foodborne ways especially consumption of raw or undercooked meat. In contrast to other foodborne infections, toxoplasmosis is a chronic infection which would make its economic and social impact much higher than even previously anticipated. Ovine meat was advanced as a major risk factor, so we investigated its parasite survey, under natural conditions. Serological MAT technique and touchdown PCR approaches were used for prevalence determination of the parasite in slaughtered sheep intended to human consumption in Tunis City. The genotyping was carried by SNPs analysis of SAG3 marker. Anti-Toxoplasma antibodies were present in 38.2% of young sheep and in 73.6% of adult sheep. Molecular detection revealed the contamination of 50% of ewes' tissue. Sequencing and SNPs analysis enabled unambiguous typing of meat isolates and revealed the presence of mixed strains as those previously identified from clinical samples in the same area. Our findings conclude that slaughtered sheep are highly infected, suggesting them as a major risk factor of Toxoplasma gondii transmission by meat consumption. Special aware should target consequently this factor when recommendations have to be established by the health care commanders.

  6. The effect of a nematode parasite on feeding and dung-burying behavior of an ecosystem engineer.

    Science.gov (United States)

    Boze, Broox G V; Moore, Janice

    2014-07-01

    Dung beetles (genus Phanaeus) consume feces in both their larval and adults forms and because of their unique dietary niche, and behaviors associated with the burial of feces, are considered ecosystem engineers. In addition, because these insects subsist on a diet composed exclusively of feces, it is likely they encounter parasitic propagules more frequently than other animals do. Parasites often alter their host's behavior, so we set out to test whether Physocephalus sexalatus (a cosmopolitan nematode parasite of ungulates) does so in ways that affect the dung beetle's role as an ecosystem engineer and/or its predator-prey relationships (transmission of the parasite). Classic tests of anti-predator behavior did not reveal behavioral differences based on the beetles' infection status. However, this parasite did alter the beetles' behaviors in ways that could be critical for its role in fecal processing and therefore ecosystem engineering. Infected beetles exhibited anorexic behavior and consumed only half the amount of feces ingested by similar uninfected beetles. Infected beetles also buried less feces and did so in tunnels that were significantly shorter than those created by uninfected beetles. Fecal burial is naturally beneficial because it aerates the soil, incorporates nitrogenous compounds, and increases the flow of water thereby making soil and pastureland more productive. We showed that the nematode parasite P. sexalatus itself becomes an ecosystem engineer as it modifies the behavior of its already influential intermediate host. © The Author 2014. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

  7. Parasitic diseases of lungs

    International Nuclear Information System (INIS)

    Rozenshtraukh, L.C.; Rybakova, N.I.; Vinner, M.G.

    1987-01-01

    Roentgenologic semiotics of the main parasitic diseases of lungs is described: echinococcosis, paragonimiasis, cysticercosis, toxoplasmosis, ascariasis, amebiosis and some rarely met parasitic diseases

  8. Floral Volatiles in Parasitic Plants of the Orobanchaceae. Ecological and Taxonomic Implications

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    Peter eTóth

    2016-03-01

    Full Text Available The holoparasitic broomrapes, Orobanche spp. and Phelipanche spp. (Orobanchaceae, are root parasites that completely depend on a host plant for survival and reproduction. There is considerable controversy on the taxonomy of this biologically and agronomically important family. Flowers of over 25 parasitic Orobanchaceae and a number of close, parasitic and non-parasitic, relatives emitted a complex blend of volatile organic compounds (VOCs, consisting of over 130 VOCs per species. Floral VOC blend-based phylogeny supported the known taxonomy in internal taxonomic grouping of genus and eliminated the uncertainty in some taxonomical groups. Moreover, phylogenetic analysis suggested separation of the broomrapes into two main groups parasitizing annual and perennial hosts, and for the annual hosts, into weedy and non-weedy broomrapes. We conclude that floral VOCs are a significant tool in species identification and possibly even in defining new species and can help to improve controversial taxonomy in the Orobanchaceae.

  9. Presence of Anti-Toxocara Antibodies in Sheep from the State of Mexico

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    Camilo Romero

    2016-01-01

    Full Text Available Toxocariasis is a parasitic zoonosis caused by the nematode Toxocara canis, and less frequently Toxocara cati, whose final hosts are the dog and cat, respectively. It is acquired by the ingestion of embryonated parasite eggs; the ingestion of meat from animals carrying cystic larvae plays a central role in this disease. The study was conducted in Ayapango, Mexico. Ninety-two sheep where used, of which 72 were females and 20 males. The total prevalence of anti-Toxocara antibodies was 15.21% (14/92, ranging from 17.24% in the one to six months age group to 14.28% in the group older sheep six months, with a higher percentage in females (19.44% compared to males (5.0%, with a significant difference between positive males and females older than six months of age (Chi-square test = 4.22, P < 0.05. The prevalence of anti-Toxocara antibodies in sheep suggests that a high number of animals are infected with Toxocara spp. The consumption of meat from paratenic hosts, including sheep, is considered a means of transmission of toxocariasis to humans.

  10. Dioctophyme renale: prevalence and risk factors of parasitism in dogs of São Cristóvão district, Três Barras county, Santa Catarina State, Brazil

    Directory of Open Access Journals (Sweden)

    Daniela Pedrassani

    Full Text Available Abstract Dioctophyme renale is a nematode that can be found parasitizing the kidney, peritoneal cavity and, rarely, other organs of canids and mustelids. This disease has high occurrence in the municipality of Três Barras, state of Santa Catarina, thus making this an interesting area to study the epidemiological aspects of infection by D. renale in dogs. Among 197 dogs, 14.2% showed the parasite eggs in urine and 16.4% showed IgG antibodies anti-D. renale in serum samples according to the indirect ELISA method; among seropositive dogs, 15 (37.5% animals did not show any parasite eggs in their urine. Parasitism was more frequent in females, and there was no finding of interference from age on parasitism. Factors such as water potential and presence of paratenic hosts in the studied region were reported by the owners of dogs and may have contributed to the occurrence of parasitism.

  11. Zoonotic enteric parasites transmitted from dogs in Egypt with special concern to Toxocara canis infection

    Science.gov (United States)

    Awadallah, Maysa A. I.; Salem, Lobna M. A.

    2015-01-01

    Aim: This work aimed to study the role played by dogs in transmitting zoonotic enteric parasites to humans in Egypt and to analyze the risk factors associated with the occurrence of such infection in dogs. Serodiagnosis of anti-Toxocara immunoglobulin G (IgG) antibodies among human beings as well as analyzing risk factors predispose to Toxocara canis infection in human beings are another objectives of this study. Materials and Methods: From June to December 2013, a total of 130 fecal samples from 4 dog populations (Military, nomadic and domiciled dogs from rural and high standard districts) and 150 stool samples of 6 occupational groups were examined for the presence of enteric parasitic infection. Moreover, 150 serum samples were collected from humans from whom stool samples were collected and examined for the presence of anti-T. canis antibodies. Results: Enteric parasites were detected in 30% of fecal samples from 4 dog populations in Egypt. High infectivity had been reported in nomadic dogs (63.33%) (Crude odds ratios [COR]=67.36, 95% confidence interval [CI]=8.09-560.8, p0.05) did not seem to have a significant association among the examined dogs. Enteric parasitic infection was reported in 31/150 human stools (20.67%). Students were the most affected groups (37.14%), followed by nomadic people (24%), house wives (20%), house guarders and military workers (12%, each), and employees (10%). The identified parasites were Cryptosporidium spp. (9.33%), Ascaris lumbercoides (3.33%), Heterophyes spp. and Ancylostoma spp. (2.66%, each) and Paragonimus spp. and Hymenolepis nana (1.33%, each). Toxocara IgG antibodies were detected in 36/150 (24%) serum samples investigated. Toxocara IgG antibodies were more prevalent in males (26.66%) than females (20%). Seroprevalence was highest (17/35, 48.57%) in 7-15 years old (COR=6.93, 95% CI=1.75-27.43, p=0.006). Seroprevalence values for T. canis antibodies were higher in those; raising dogs (29.85%), eating raw vegetables (25

  12. Host-Parasite Interactions and Purifying Selection in a Microsporidian Parasite of Honey Bees.

    Science.gov (United States)

    Huang, Qiang; Chen, Yan Ping; Wang, Rui Wu; Cheng, Shang; Evans, Jay D

    2016-01-01

    To clarify the mechanisms of Nosema ceranae parasitism, we deep-sequenced both honey bee host and parasite mRNAs throughout a complete 6-day infection cycle. By time-series analysis, 1122 parasite genes were significantly differently expressed during the reproduction cycle, clustering into 4 expression patterns. We found reactive mitochondrial oxygen species modulator 1 of the host to be significantly down regulated during the entire infection period. Our data support the hypothesis that apoptosis of honey bee cells was suppressed during infection. We further analyzed genome-wide genetic diversity of this parasite by comparing samples collected from the same site in 2007 and 2013. The number of SNP positions per gene and the proportion of non-synonymous substitutions per gene were significantly reduced over this time period, suggesting purifying selection on the parasite genome and supporting the hypothesis that a subset of N. ceranae strains might be dominating infection.

  13. Theileria parasites secrete a prolyl isomerase to maintain host leukocyte transformation.

    Science.gov (United States)

    Marsolier, J; Perichon, M; DeBarry, J D; Villoutreix, B O; Chluba, J; Lopez, T; Garrido, C; Zhou, X Z; Lu, K P; Fritsch, L; Ait-Si-Ali, S; Mhadhbi, M; Medjkane, S; Weitzman, J B

    2015-04-16

    Infectious agents develop intricate mechanisms to interact with host cell pathways and hijack their genetic and epigenetic machinery to change host cell phenotypic states. Among the Apicomplexa phylum of obligate intracellular parasites, which cause veterinary and human diseases, Theileria is the only genus that transforms its mammalian host cells. Theileria infection of bovine leukocytes induces proliferative and invasive phenotypes associated with activated signalling pathways, notably JNK and AP-1 (ref. 2). The transformed phenotypes are reversed by treatment with the theilericidal drug buparvaquone. We used comparative genomics to identify a homologue of the peptidyl-prolyl isomerase PIN1 in T. annulata (TaPIN1) that is secreted into the host cell and modulates oncogenic signalling pathways. Here we show that TaPIN1 is a bona fide prolyl isomerase and that it interacts with the host ubiquitin ligase FBW7, leading to its degradation and subsequent stabilization of c-JUN, which promotes transformation. We performed in vitro and in silico analysis and in vivo zebrafish xenograft experiments to demonstrate that TaPIN1 is directly inhibited by the anti-parasite drug buparvaquone (and other known PIN1 inhibitors) and is mutated in a drug-resistant strain. Prolyl isomerization is thus a conserved mechanism that is important in cancer and is used by Theileria parasites to manipulate host oncogenic signalling.

  14. Striga parasitizes transgenic hairy roots of Zea mays and provides a tool for studying plant-plant interactions

    Directory of Open Access Journals (Sweden)

    Runo Steven

    2012-06-01

    Full Text Available Abstract Background Striga species are noxious root hemi-parasitic weeds that debilitate cereal production in sub-Saharan Africa (SSA. Control options for Striga are limited and developing Striga resistant crop germplasm is regarded as the best and most sustainable control measure. Efforts to improve germplasm for Striga resistance by a non-Genetic Modification (GM approach, for example by exploiting natural resistance, or by a GM approach are constrained by limited information on the biological processes underpinning host-parasite associations. Additionaly, a GM approach is stymied by lack of availability of candidate resistance genes for introduction into hosts and robust transformation methods to validate gene functions. Indeed, a majority of Striga hosts, the world’s most cultivated cereals, are recalcitrant to genetic transformation. In maize, the existing protocols for transformation and regeneration are tedious, lengthy, and highly genotype-specific with low efficiency of transformation. Results We used Agrobacterium rhizogenes strain K599 carrying a reporter gene construct, Green Fluorescent Protein (GFP, to generate transgenic composite maize plants that were challenged with the parasitic plant Striga hermonthica. Eighty five percent of maize plants produced transgenic hairy roots expressing GFP. Consistent with most hairy roots produced in other species, transformed maize roots exhibited a hairy root phenotype, the hallmark of A. rhizogenes mediated transformation. Transgenic hairy roots resulting from A. rhizogenes transformation were readily infected by S. hermonthica. There were no significant differences in the number and size of S. hermonthica individuals recovered from either transgenic or wild type roots. Conclusions This rapid, high throughput, transformation technique will advance our understanding of gene function in parasitic plant-host interactions.

  15. Factors Associated with Gastrointestinal Parasitic Infections among Young Population in Northeast Brazil

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    Juliana Vasconcelos Lyra da Silva

    2016-01-01

    Full Text Available Background. Intestinal parasitic infections constitute a major public health problem that is frequently associated with poverty, inadequate sanitation, and the nutritional status of the population. Objective. The aim of the present study is to investigate the possible association of parasitic infections, sanitary conditions, hygiene practices, and the nutritional and socioeconomic status of a poor youth population. Methods. A cross-sectional study was conducted with 367 children and adolescents inhabiting a substandard settlement in the urban area of Maceió (Alagoas State, Brazil. Data collection included socioeconomic status, anthropometric measurements, fecal sample examinations, and laboratory blood analysis. The identification of factors associated with gastrointestinal parasitic infections was undertaken through bi- and multivariate analyses. Results. Stool sample analysis obtained from 300 individuals revealed that 204 (68% were infected with at least one parasite species and of these 130 (63.7% were polyparasitized. No significant associations were identified between low height for age (stunted, parasitic infections, and polyparasitism. There was also no association between family income and parasitosis. However, low socioeconomic status proved to be a potential risk factor for parasitic infections. Conclusion. Actions must be taken to improve sanitation, housing, and environmental conditions in order to eliminate the risk factors for parasitic infections, and thereby guarantee a better quality of life for this population.

  16. A lean and agile construction system as a set of countermeasures to improve health, safety and productivity in mechanical and electrical construction

    OpenAIRE

    Court, PF; Pasquire, CL; Gibb, AGF

    2009-01-01

    This paper presents certain aspects of the findings of a research project to develop and implement a Lean and agile mechanical and electrical (M&E) Construction System on a case study project. The objective of the research project for the sponsor company is to improve its projects site operations making them safer for the worker and improving efficiency and productivity by overcoming the problems and issues that it faces in the M&E industry within the UK construction sector. The research find...

  17. New nanomicelle curcumin formulation for ocular delivery: improved stability, solubility, and ocular anti-inflammatory treatment.

    Science.gov (United States)

    Li, Mengshuang; Xin, Meng; Guo, Chuanlong; Lin, Guiming; Wu, Xianggen

    2017-11-01

    A stable topical ophthalmic curcumin formulation with high solubility, stability, and efficacy is needed for pharmaceutical use in clinics. The objective of this article was to describe a novel curcumin containing a nanomicelle formulation using a polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol (PVCL-PVA-PEG) graft copolymer. Nanomicelle curcumin was formulated and optimized and then further evaluated for in vitro cytotoxicity/in vivo ocular irritation, in vitro cellular uptake/in vivo corneal permeation, and in vitro antioxidant activity/in vivo anti-inflammatory efficacy. The solubility, chemical stability, and antioxidant activity were greatly improved after the encapsulation of the PVCL-PVA-PEG nanomicelles. The nanomicelle curcumin ophthalmic solution was simple to prepare and the nanomicelles are stable to the storage conditions, and it had good cellular tolerance. Nanomicelle curcumin also had excellent ocular tolerance in rabbits. The use of nanomicelles significantly improved in vitro cellular uptake and in vivo corneal permeation as well as improved anti-inflammatory efficacy when compared with a free curcumin solution. These findings indicate that nanomicelles could be promising topical delivery systems for the ocular administration of curcumin.

  18. Rethinking the extrinsic incubation period of malaria parasites.

    Science.gov (United States)

    Ohm, Johanna R; Baldini, Francesco; Barreaux, Priscille; Lefevre, Thierry; Lynch, Penelope A; Suh, Eunho; Whitehead, Shelley A; Thomas, Matthew B

    2018-03-12

    The time it takes for malaria parasites to develop within a mosquito, and become transmissible, is known as the extrinsic incubation period, or EIP. EIP is a key parameter influencing transmission intensity as it combines with mosquito mortality rate and competence to determine the number of mosquitoes that ultimately become infectious. In spite of its epidemiological significance, data on EIP are scant. Current approaches to estimate EIP are largely based on temperature-dependent models developed from data collected on parasite development within a single mosquito species in the 1930s. These models assume that the only factor affecting EIP is mean environmental temperature. Here, we review evidence to suggest that in addition to mean temperature, EIP is likely influenced by genetic diversity of the vector, diversity of the parasite, and variation in a range of biotic and abiotic factors that affect mosquito condition. We further demonstrate that the classic approach of measuring EIP as the time at which mosquitoes first become infectious likely misrepresents EIP for a mosquito population. We argue for a better understanding of EIP to improve models of transmission, refine predictions of the possible impacts of climate change, and determine the potential evolutionary responses of malaria parasites to current and future mosquito control tools.

  19. Intestinal Parasitic Infections in Human Immunodeficiency Virus-Infected and Noninfected Persons in a High Human Immunodeficiency Virus Prevalence Region of Cameroon.

    Science.gov (United States)

    Nkenfou, Céline Nguefeu; Tchameni, Sandrine Mboula; Nkenfou, Carine Nguefeu; Djataou, Patrice; Simo, Ulrich Florian; Nkoum, Alexandre Benjamin; Estrin, William

    2017-09-01

    The problem of intestinal parasitic infection in human immunodeficiency virus (HIV)-infected people requires careful consideration in the developing world where poor nutrition is associated with poor hygiene and several coinfecting diseases. Studies have addressed this issue in Cameroon, especially in the low HIV prevalence area. The current study was conducted to determine the prevalence of intestinal parasitosis in people living with HIV (PLHIV) in Adamaoua and to identify associated risk factors. Stool and blood specimens from study participants were screened for intestinal parasites and anti-HIV antibodies, respectively. Of 235 participants, 68 (28.9%) were HIV positive, 38 of them on antiretroviral treatment (ART). The overall prevalence of intestinal parasites was 32.3%. Of 68 PLHIV, 32.3% (22/68) were infected with intestinal parasites, compared with 32.3% (54/167) of the HIV-negative patients. Univariate analysis showed no difference between the prevalence of intestinal parasites among PLHIV and HIV-negative patients ( P = 0.69). ART was not associated with the prevalence of intestinal parasites. Multivariate analysis showed that the quality of water and the personal hygiene were the major risk factors associated to intestinal parasitosis. The level of education was associated with HIV serostatus: the higher the level of education, the lower the risk of being infected with HIV ( P = 0.00). PLHIV and the general population should be screened routinely for intestinal parasites and treated if infected.

  20. Parasite prevalence corresponds to host life history in a diverse assemblage of afrotropical birds and haemosporidian parasites.

    Directory of Open Access Journals (Sweden)

    Holly L Lutz

    Full Text Available Avian host life history traits have been hypothesized to predict rates of infection by haemosporidian parasites. Using molecular techniques, we tested this hypothesis for parasites from three haemosporidian genera (Plasmodium, Haemoproteus, and Leucocytozoon collected from a diverse sampling of birds in northern Malawi. We found that host life history traits were significantly associated with parasitism rates by all three parasite genera. Nest type and nest location predicted infection probability for all three parasite genera, whereas flocking behavior is an important predictor of Plasmodium and Haemoproteus infection and habitat is an important predictor of Leucocytozoon infection. Parasite prevalence was 79.1% across all individuals sampled, higher than that reported for comparable studies from any other region of the world. Parasite diversity was also exceptionally high, with 248 parasite cytochrome b lineages identified from 152 host species. A large proportion of Plasmodium, Haemoproteus, and Leucocytozoon parasite DNA sequences identified in this study represent new, previously undocumented lineages (n = 201; 81% of total identified based on BLAST queries against the avian malaria database, MalAvi.

  1. Linking parasite populations in hosts to parasite populations in space through Taylor's law and the negative binomial distribution.

    Science.gov (United States)

    Cohen, Joel E; Poulin, Robert; Lagrue, Clément

    2017-01-03

    The spatial distribution of individuals of any species is a basic concern of ecology. The spatial distribution of parasites matters to control and conservation of parasites that affect human and nonhuman populations. This paper develops a quantitative theory to predict the spatial distribution of parasites based on the distribution of parasites in hosts and the spatial distribution of hosts. Four models are tested against observations of metazoan hosts and their parasites in littoral zones of four lakes in Otago, New Zealand. These models differ in two dichotomous assumptions, constituting a 2 × 2 theoretical design. One assumption specifies whether the variance function of the number of parasites per host individual is described by Taylor's law (TL) or the negative binomial distribution (NBD). The other assumption specifies whether the numbers of parasite individuals within each host in a square meter of habitat are independent or perfectly correlated among host individuals. We find empirically that the variance-mean relationship of the numbers of parasites per square meter is very well described by TL but is not well described by NBD. Two models that posit perfect correlation of the parasite loads of hosts in a square meter of habitat approximate observations much better than two models that posit independence of parasite loads of hosts in a square meter, regardless of whether the variance-mean relationship of parasites per host individual obeys TL or NBD. We infer that high local interhost correlations in parasite load strongly influence the spatial distribution of parasites. Local hotspots could influence control and conservation of parasites.

  2. Host-Parasite Interactions and Purifying Selection in a Microsporidian Parasite of Honey Bees.

    Directory of Open Access Journals (Sweden)

    Qiang Huang

    Full Text Available To clarify the mechanisms of Nosema ceranae parasitism, we deep-sequenced both honey bee host and parasite mRNAs throughout a complete 6-day infection cycle. By time-series analysis, 1122 parasite genes were significantly differently expressed during the reproduction cycle, clustering into 4 expression patterns. We found reactive mitochondrial oxygen species modulator 1 of the host to be significantly down regulated during the entire infection period. Our data support the hypothesis that apoptosis of honey bee cells was suppressed during infection. We further analyzed genome-wide genetic diversity of this parasite by comparing samples collected from the same site in 2007 and 2013. The number of SNP positions per gene and the proportion of non-synonymous substitutions per gene were significantly reduced over this time period, suggesting purifying selection on the parasite genome and supporting the hypothesis that a subset of N. ceranae strains might be dominating infection.

  3. The Meaning of Anti-Americanism: A Performative Approach to Anti-American Prejudice

    Directory of Open Access Journals (Sweden)

    Felix Knappertsbusch

    2013-06-01

    Full Text Available A contribution to the ongoing debate on how anti-Americanism can be adequately conceptualized and how such prejudice can be distinguished from legitimate criticism, arguing that part of these conceptual problems arise from a too narrow focus on defining anti-Americanism and the use of standardized empirical operationalizations. Such approaches exhibit severe limitations in grasping the flexibility of the phenomenon in everyday discourse and often underestimate or ignore the interpretive aspect involved in identifying utterances as anti-American prejudice. Alternatively, a performative approach is proposed, understanding anti-Americanism as a network of speech acts bound by family resemblance rather than identical features. In combination with qualitative empirical research methods such a conceptualization is especially suited to account for the flexible, situated use of anti-American utterances. At the same time it grants reflexivity to the research concept, in the sense of a close description of the scientific application of the notion of anti-Americanism. Two empirical examples from an interview study on anti-American speech in Germany illustrate the potential of such an approach, providing an insight into how anti-Americanism is incorporated into the construction and expression of racist and revisionist national identifications in everyday discourse.

  4. Effect of Pollen Feed on Parasitization and Predatism of Cephalonomia stephanoderis onHypothenemus hampei

    Directory of Open Access Journals (Sweden)

    Dwi Suci Rahayu

    2014-05-01

    Full Text Available Biological control of the coffee berry borer (Hypothenemus hampeiusing parasitoid Cephalonomia stephanoderishas been developed through the improvement of the parasitoid role may using pollens as feed source. The objective of this study was to investigate the effect of cover crop and weed pollens on parasitization and predatism of C. stephanoderis.The applied treatments were pollens of Turnera ulmifolia, Arachis pintoi, Ageratum conyzoidesadded in glass tube that consist of 10 CBB pupaes and a mated female of C. stephanoderis. Number of pupae parasitized and pupae preyed were observed. The result showed that addition of A. Pintoi pollen increased the number of pupae parasitized at 135% whereas addition of T. ulmifolia and A. conyzoides pollens did not affect parasitization of C. Stephanoderis. The predatismof C. stephanoderiswas higher than parasitization to pupae of H. hampei which showed that the behavior of C. stephanoderiswas parasitization. Addition of T. ulmifolia, A. pintoi, and A. conyzoidespollens increased the number of pupae predatism at 132%, 102%, and 225%, respectively. Key words: Ageratum conyzoides, Arachis pintoi, Cephalonomia stephanoderis, Hypothenemus hampei,parasitization, predatism, pollens, Turnera ulmifolia

  5. Foodborne parasites from wildlife

    DEFF Research Database (Denmark)

    Kapel, Christian Moliin Outzen; Fredensborg, Brian Lund

    2015-01-01

    The majority of wild foods consumed by humans are sourced from intensively managed or semi-farmed populations. Management practices inevitably affect wildlife density and habitat characteristics, which are key elements in the transmission of parasites. We consider the risk of transmission...... of foodborne parasites to humans from wildlife maintained under natural or semi-natural conditions. A deeper understanding will be useful in counteracting foodborne parasites arising from the growing industry of novel and exotic foods....

  6. Simulated selection responses for breeding programs including resistance and resilience to parasites in Creole goats

    NARCIS (Netherlands)

    Gunia, M.; Phocas, F.; Gourdine, J.L.; Bijma, P.; Mandonnet, N.

    2013-01-01

    The Creole goat is a local breed used for meat production in Guadeloupe (French West Indies). As in other tropical countries, improvement of parasite resistance is needed. In this study, we compared predicted selection responses for alternative breeding programs with or without parasites resistance

  7. PARASITES OF FISH

    Science.gov (United States)

    The intent of this chapter is to describe the parasites of importance to fishes maintained and used in laboratory settings. In contrast to the frist edition, the focus will be only on those parasites that pose a serious threat to or are common in fishes held in these confined en...

  8. Toxoplasma gondii 70 kDa heat shock protein: systemic detection is associated with the death of the parasites by the immune response and its increased expression in the brain is associated with parasite replication.

    Directory of Open Access Journals (Sweden)

    Paulo Victor Czarnewski Barenco

    Full Text Available The heat shock protein of Toxoplasma gondii (TgHSP70 is a parasite virulence factor that is expressed during T. gondii stage conversion. To verify the effect of dexamethasone (DXM-induced infection reactivation in the TgHSP70-specific humoral immune response and the presence of the protein in the mouse brain, we produced recombinant TgHSP70 and anti-TgHSP70 IgY antibodies to detect the protein, the specific antibody and levels of immune complexes (ICs systemically, as well as the protein in the brain of resistant (BALB/c and susceptible (C57BL/6 mice. It was observed higher TgHSP70-specific antibody titers in serum samples of BALB/c compared with C57BL/6 mice. However, the susceptible mice presented the highest levels of TgHSP70 systemically and no detection of specific ICs. The DXM treatment induced increased parasitism and lower inflammatory changes in the brain of C57BL/6, but did not interfere with the cerebral parasitism in BALB/c mice. Additionally, DXM treatment decreased the serological TgHSP70 concentration in both mouse lineages. C57BL/6 mice presented high expression of TgHSP70 in the brain with the progression of infection and under DXM treatment. Taken together, these data indicate that the TgHSP70 release into the bloodstream depends on the death of the parasites mediated by the host immune response, whereas the increased TgHSP70 expression in the brain depends on the multiplication rate of the parasite.

  9. Challenges for Improvement of Quality in Construction of a Growing Economy

    Directory of Open Access Journals (Sweden)

    S. Chan Loong

    2005-12-01

    Full Text Available This paper highlights the results of a questionnaire survey amongst contractors and contracting consultants in a growing economy. The survey was intended to explore the problems that the employees think might affect the quality of construction works. Thirteen factors known to have some bearing on the quality of construction have been identified through literature and were used as a basis for the survey. The findings of the survey revealed that there is a need to focus on the human factors in addressing the quality issue. The four most problematic factors indicated by the respondents are lack of information, time constraint, lack of teamwork and poor communication. The results indicated the importance of a unified force; an enhanced coordination flow and improved teamwork are required to achieve the project quality objectives. A quality system will not succeed unless both the technical and humanistic aspects are addressed. These are some of the challenges that construction-related organisations must address to continually improve their quality of products and services to be able to compete aggressively in an environment where the quality requirements are always rising.

  10. Zoonotic parasites associated with felines from the Patagonian Holocene

    Directory of Open Access Journals (Sweden)

    Martín Horacio Fugassa

    2009-12-01

    Full Text Available Feline coprolites were examined for parasites with the aim of studying ancient infections that occurred in the Patagonian region during the Holocene period. Eggs compatible to Trichuris sp., Calodium sp., Eucoleus sp., Nematodirus sp., Oesophagostomum sp. (Nematoda, Monoecocestus sp. (Cestoda and Eimeria macusaniensis (Coccidia were recovered from faecal samples. The results obtained from the analysis provide evidence of consumption by felids of the viscera of both rodents and camelids. This knowledge allows for improved explanations as to the distribution of parasitism and its significance to the health of humans and animals inhabiting the area under study during the Middle Holocene.

  11. Reduced helminth parasitism in the introduced bank vole (Myodes glareolus: More parasites lost than gained

    Directory of Open Access Journals (Sweden)

    Karen C. Loxton

    2016-08-01

    Full Text Available Introduced species are often less parasitised compared to their native counterparts and to ecologically similar hosts in the new environment. Reduced parasitism may come about due to both the loss of original parasites and low acquisition of novel parasites. In this study we investigated the intestinal helminth parasites of the introduced bank vole (Myodes glareolus in Ireland. Results were compared to data from other European studies and to the intestinal helminth fauna of an ecologically similar native rodent in Ireland, the wood mouse (Apodemus sylvaticus. The helminth fauna of introduced bank voles exhibited low diversity with only 3 species recovered: Aspiculuris tianjinensis; Aonchotheca murissylvatici and Taenia martis larvae. In particular, no adult parasites with indirect life-cycles were found in bank voles suggesting that indirectly transmitted parasites are less likely to establish in invasive hosts. Also, the results of this study add support to the enemy release hypothesis.

  12. 32 CFR 644.486 - Disposal of buildings and improvements constructed under emergency plant facilities (EPF) or...

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Disposal of buildings and improvements constructed under emergency plant facilities (EPF) or similar contracts. 644.486 Section 644.486 National... Disposal of buildings and improvements constructed under emergency plant facilities (EPF) or similar...

  13. Parasites and immunotherapy: with or against?

    Science.gov (United States)

    Yousofi Darani, Hossein; Yousefi, Morteza; Safari, Marzieh; Jafari, Rasool

    2016-06-01

    Immunotherapy is a sort of therapy in which antibody or antigen administrates to the patient in order to treat or reduce the severity of complications of disease. This kind of treatment practiced in a wide variety of diseases including infectious diseases, autoimmune disorders, cancers and allergy. Successful and unsuccessful immunotherapeutic strategies have been practiced in variety of parasitic infections. On the other hand parasites or parasite antigens have also been considered for immunotherapy against other diseases such as cancer, asthma and multiple sclerosis. In this paper immunotherapy against common parasitic infections, and also immunotherapy of cancer, asthma and multiple sclerosis with parasites or parasite antigens have been reviewed.

  14. Parasitic worms: how many really?

    Science.gov (United States)

    Strona, Giovanni; Fattorini, Simone

    2014-04-01

    Accumulation curves are useful tools to estimate species diversity. Here we argue that they can also be used in the study of global parasite species richness. Although this basic idea is not completely new, our approach differs from the previous ones as it treats each host species as an independent sample. We show that randomly resampling host-parasite records from the existing databases makes it possible to empirically model the relationship between the number of investigated host species, and the corresponding number of parasite species retrieved from those hosts. This method was tested on 21 inclusive lists of parasitic worms occurring on vertebrate hosts. All of the obtained models conform well to a power law curve. These curves were then used to estimate global parasite species richness. Results obtained with the new method suggest that current predictions are likely to severely overestimate parasite diversity. Copyright © 2014 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

  15. Anti-Taenia solium monoclonal antibodies for the detection of parasite antigens in body fluids from patients with neurocysticercosis.

    Science.gov (United States)

    Paredes, Adriana; Sáenz, Patricia; Marzal, Miguel W; Orrego, Miguel A; Castillo, Yesenia; Rivera, Andrea; Mahanty, Siddhartha; Guerra-Giraldez, Cristina; García, Hector H; Nash, Theodore E

    2016-07-01

    Neurocysticercosis (NCC), an infection of the brain by Taenia solium (Ts) cysts, is the most common cause of adult-onset epilepsy in developing countries. Serological testing consists primarily of varying methods to detect antibodies in body fluids and more recently antigen (Ag) detection assays to identify individuals or animals with viable parasites. Antigen assays currently in use employ monoclonal antibodies (mAbs) raised against T. saginata, which have known cross reactivity to animal cestodes but are highly specific in human samples. We produced, characterized and tested 21 mAbs raised against T. solium whole cyst antigens, vesicular fluid or excretory secretory products. Reactivity of the TsmAbs against specific cyst structures was determined using immunofluorescence and immunohistochemistry on histological sections of Ts muscle cysts. Four TsmAbs reacted to vesicular space alone, 9 to the neck and cyst wall, one to the neck and vesicular space and 7 to the neck, cyst wall and vesicular space. An in-house ELISA assay to detect circulating Ts antigen, using the TsmAbs as capture antibodies and a rabbit polyclonal anti-Ts whole cyst antibody as a detector antibody demonstrated that eight of the 21 TsmAbs detected antigens in known NCC-positive human sera and three of these also in urine samples. Reactivity was expressed as normalized ratios of optical densities (OD positive control/OD negative control). Three TsmAbs had ratios >10 and five between 2 and 10. The TsmAbs have potential utility for the diagnosis and post-treatment monitoring of patients with viable NCC infections. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Host-parasite interactions and ecology of the malaria parasite-a bioinformatics approach.

    Science.gov (United States)

    Izak, Dariusz; Klim, Joanna; Kaczanowski, Szymon

    2018-04-25

    Malaria remains one of the highest mortality infectious diseases. Malaria is caused by parasites from the genus Plasmodium. Most deaths are caused by infections involving Plasmodium falciparum, which has a complex life cycle. Malaria parasites are extremely well adapted for interactions with their host and their host's immune system and are able to suppress the human immune system, erase immunological memory and rapidly alter exposed antigens. Owing to this rapid evolution, parasites develop drug resistance and express novel forms of antigenic proteins that are not recognized by the host immune system. There is an emerging need for novel interventions, including novel drugs and vaccines. Designing novel therapies requires knowledge about host-parasite interactions, which is still limited. However, significant progress has recently been achieved in this field through the application of bioinformatics analysis of parasite genome sequences. In this review, we describe the main achievements in 'malarial' bioinformatics and provide examples of successful applications of protein sequence analysis. These examples include the prediction of protein functions based on homology and the prediction of protein surface localization via domain and motif analysis. Additionally, we describe PlasmoDB, a database that stores accumulated experimental data. This tool allows data mining of the stored information and will play an important role in the development of malaria science. Finally, we illustrate the application of bioinformatics in the development of population genetics research on malaria parasites, an approach referred to as reverse ecology.

  17. In Vitro Variant Surface Antigen Expression in Plasmodium falciparum Parasites from a Semi-Immune Individual Is Not Correlated with Var Gene Transcription

    Science.gov (United States)

    Tschan, Serena; Flötenmeyer, Matthias; Koch, Iris; Berger, Jürgen; Kremsner, Peter; Frank, Matthias

    2016-01-01

    Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) is considered to be the main variant surface antigen (VSA) of Plasmodium falciparum and is mainly localized on electron-dense knobs in the membrane of the infected erythrocyte. Switches in PfEMP1 expression provide the basis for antigenic variation and are thought to be critical for parasite persistence during chronic infections. Recently, strain transcending anti-PfEMP1 immunity has been shown to develop early in life, challenging the role of PfEMP1 in antigenic variation during chronic infections. In this work we investigate how P. falciparum achieves persistence during a chronic asymptomatic infection. The infected individual (MOA) was parasitemic for 42 days and multilocus var gene genotyping showed persistence of the same parasite population throughout the infection. Parasites from the beginning of the infection were adapted to tissue culture and cloned by limiting dilution. Flow cytometry using convalescent serum detected a variable surface recognition signal on isogenic clonal parasites. Quantitative real-time PCR with a field isolate specific var gene primer set showed that the surface recognition signal was not correlated with transcription of individual var genes. Strain transcending anti-PfEMP1 immunity of the convalescent serum was demonstrated with CD36 selected and PfEMP1 knock-down NF54 clones. In contrast, knock-down of PfEMP1 did not have an effect on the antibody recognition signal in MOA clones. Trypsinisation of the membrane surface proteins abolished the surface recognition signal and immune electron microscopy revealed that antibodies from the convalescent serum bound to membrane areas without knobs and with knobs. Together the data indicate that PfEMP1 is not the main variable surface antigen during a chronic infection and suggest a role for trypsin sensitive non-PfEMP1 VSAs for parasite persistence in chronic infections. PMID:27907004

  18. Construction of Expression Vector for Anti-Alpha-Fetoprotein Gene and Its Inhibition Effects on Alpha-Fetoprotein Positive Hepg2 Cells

    Science.gov (United States)

    Wang, Ze; Zhang, Hui

    As research previously demonstrated, suppression of AFP expression or its biological activities might inhibit the proliferation of AFP positive human hepatocellular carcinoma cells. In this study, we constructed an anti-AFP gene vector and transfected it to HepG2 cells. RT-PCR showed AFP gene expression in the transfected cells was reduced. MTT assay suggested the proliferation of the transfected cells was also inhibited comparing with the untransfected cells. This result provides a new insight into AFP as the target for preventing and treating hepatocellular carcinoma.

  19. An annotated list of fish parasites (Isopoda, Copepoda, Monogenea, Digenea, Cestoda, Nematoda) collected from Snappers and Bream (Lutjanidae, Nemipteridae, Caesionidae) in New Caledonia confirms high parasite biodiversity on coral reef fish.

    Science.gov (United States)

    Justine, Jean-Lou; Beveridge, Ian; Boxshall, Geoffrey A; Bray, Rodney A; Miller, Terrence L; Moravec, František; Trilles, Jean-Paul; Whittington, Ian D

    2012-09-04

    Coral reefs are areas of maximum biodiversity, but the parasites of coral reef fishes, and especially their species richness, are not well known. Over an 8-year period, parasites were collected from 24 species of Lutjanidae, Nemipteridae and Caesionidae off New Caledonia, South Pacific. Host-parasite and parasite-host lists are provided, with a total of 207 host-parasite combinations and 58 parasite species identified at the species level, with 27 new host records. Results are presented for isopods, copepods, monogeneans, digeneans, cestodes and nematodes. When results are restricted to well-sampled reef fish species (sample size > 30), the number of host-parasite combinations is 20-25 per fish species, and the number of parasites identified at the species level is 9-13 per fish species. Lutjanids include reef-associated fish and deeper sea fish from the outer slopes of the coral reef: fish from both milieus were compared. Surprisingly, parasite biodiversity was higher in deeper sea fish than in reef fish (host-parasite combinations: 12.50 vs 10.13, number of species per fish 3.75 vs 3.00); however, we identified four biases which diminish the validity of this comparison. Finally, these results and previously published results allow us to propose a generalization of parasite biodiversity for four major families of reef-associated fishes (Lutjanidae, Nemipteridae, Serranidae and Lethrinidae): well-sampled fish have a mean of 20 host-parasite combinations per fish species, and the number of parasites identified at the species level is 10 per fish species. Since all precautions have been taken to minimize taxon numbers, it is safe to affirm than the number of fish parasites is at least ten times the number of fish species in coral reefs, for species of similar size or larger than the species in the four families studied; this is a major improvement to our estimate of biodiversity in coral reefs. Our results suggest that extinction of a coral reef fish species

  20. Parasite specialization in a unique habitat: hummingbirds as reservoirs of generalist blood parasites of Andean birds.

    Science.gov (United States)

    Moens, Michaël A J; Valkiūnas, Gediminas; Paca, Anahi; Bonaccorso, Elisa; Aguirre, Nikolay; Pérez-Tris, Javier

    2016-09-01

    Understanding how parasites fill their ecological niches requires information on the processes involved in the colonization and exploitation of unique host species. Switching to hosts with atypical attributes may favour generalists broadening their niches or may promote specialization and parasite diversification as the consequence. We analysed which blood parasites have successfully colonized hummingbirds, and how they have evolved to exploit such a unique habitat. We specifically asked (i) whether the assemblage of Haemoproteus parasites of hummingbirds is the result of single or multiple colonization events, (ii) to what extent these parasites are specialized in hummingbirds or shared with other birds and (iii) how hummingbirds contribute to sustain the populations of these parasites, in terms of both prevalence and infection intensity. We sampled 169 hummingbirds of 19 species along an elevation gradient in Southern Ecuador to analyse the host specificity, diversity and infection intensity of Haemoproteus by molecular and microscopy techniques. In addition, 736 birds of 112 species were analysed to explore whether hummingbird parasites are shared with other birds. Hummingbirds hosted a phylogenetically diverse assemblage of generalist Haemoproteus lineages shared with other host orders. Among these parasites, Haemoproteus witti stood out as the most generalized. Interestingly, we found that infection intensities of this parasite were extremely low in passerines (with no detectable gametocytes), but very high in hummingbirds, with many gametocytes seen. Moreover, infection intensities of H. witti were positively correlated with the prevalence across host species. Our results show that hummingbirds have been colonized by generalist Haemoproteus lineages on multiple occasions. However, one of these generalist parasites (H. witti) seems to be highly dependent on hummingbirds, which arise as the most relevant reservoirs in terms of both prevalence and

  1. Protease-associated cellular networks in malaria parasite Plasmodium falciparum

    Directory of Open Access Journals (Sweden)

    Lilburn Timothy G

    2011-12-01

    Full Text Available Abstract Background Malaria continues to be one of the most severe global infectious diseases, responsible for 1-2 million deaths yearly. The rapid evolution and spread of drug resistance in parasites has led to an urgent need for the development of novel antimalarial targets. Proteases are a group of enzymes that play essential roles in parasite growth and invasion. The possibility of designing specific inhibitors for proteases makes them promising drug targets. Previously, combining a comparative genomics approach and a machine learning approach, we identified the complement of proteases (degradome in the malaria parasite Plasmodium falciparum and its sibling species 123, providing a catalog of targets for functional characterization and rational inhibitor design. Network analysis represents another route to revealing the role of proteins in the biology of parasites and we use this approach here to expand our understanding of the systems involving the proteases of P. falciparum. Results We investigated the roles of proteases in the parasite life cycle by constructing a network using protein-protein association data from the STRING database 4, and analyzing these data, in conjunction with the data from protein-protein interaction assays using the yeast 2-hybrid (Y2H system 5, blood stage microarray experiments 678, proteomics 9101112, literature text mining, and sequence homology analysis. Seventy-seven (77 out of 124 predicted proteases were associated with at least one other protein, constituting 2,431 protein-protein interactions (PPIs. These proteases appear to play diverse roles in metabolism, cell cycle regulation, invasion and infection. Their degrees of connectivity (i.e., connections to other proteins, range from one to 143. The largest protease-associated sub-network is the ubiquitin-proteasome system which is crucial for protein recycling and stress response. Proteases are also implicated in heat shock response, signal peptide

  2. Factors and values of willingness to pay for improved construction waste management--a perspective of Malaysian contractors.

    Science.gov (United States)

    Begum, Rawshan Ara; Siwar, Chamhuri; Pereira, Joy Jacqueline; Jaafar, Abdul Hamid

    2007-01-01

    Malaysia is facing an increase in the generation of waste and of accompanying problems with the disposal of this waste. In the last two decades, extensive building and infrastructure development projects have led to an increase in the generation of construction waste material. The construction industry has a substantial impact on the environment, and its environmental effects are in direct relation to the quality and quantity of the waste it generates. This paper discusses general characteristics of the construction contractors, the contractors' willingness to pay (WTP) for improved construction waste management, determining factors which affect the amount of their willingness to pay, and suggestions and policy implications in the perspective of construction waste management in Malaysia. The data in this study is based on contractors registered with the construction industry development board (CIDB) of Malaysia. Employing the open ended contingent valuation method, the study assessed the contractors' average maximum WTP for improved construction waste management to be RM69.88 (1US$=3.6 RM) per tonne of waste. The result shows that the average maximum WTP is higher for large contractors than for medium and small contractors. The highest average maximum WTP value is RM88.00 for Group A (large contractors) RM78.25 for Group B (medium-size contractors) and RM55.80 for Group C (small contractors). One of the contributions of this study is to highlight the difference of CIDB registration grade in the WTP for improved construction waste management. It is found that contractors' WTP for improved waste collection and disposal services increases with the increase in contractors' current paid up capital. The identified factors and determinants of the WTP will assist the formulation of appropriate policies in addressing the construction waste problem in Malaysia and indirectly improve the quality of construction in the country.

  3. Immunity to parasitic infection

    National Research Council Canada - National Science Library

    Lamb, Tracey J

    2012-01-01

    .... Often endemic in developing countries many parasitic diseases are neglected in terms of research funding and much remains to be understood about parasites and the interactions they have with the immune system...

  4. Immunity to parasitic infection

    National Research Council Canada - National Science Library

    Lamb, Tracey J

    2012-01-01

    ... may be manipulated to develop therapeutic interventions against parasitic infection. For easy reference, the most commonly studied parasites are examined in individual chapters written by investigators at the forefront of their field...

  5. 9 CFR 381.88 - Parasites.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Parasites. 381.88 Section 381.88 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... § 381.88 Parasites. Organs or other parts of carcasses which are found to be infested with parasites, or...

  6. Parasitic infections of the external eye.

    Science.gov (United States)

    Pahuja, Shivani; Puranik, Charuta; Jelliti, Bechir; Khairallah, Moncef; Sangwan, Virender S

    2013-08-01

    To review the published literature on parasitic infections of external eye. Published articles and case reports on parasitic infections of external eye were reviewed and relevant information was collected. Parasitic infections of the eye are rare. However, being more commonly seen in developing nations, they require active measures for screening, diagnosis, and therapy. Parasites of importance causing external ocular disease are protozoan parasites, such as Leishmania; metazoans, such as nematodes (roundworms), cestodes (tapeworms), and trematodes (flatworms); or ectoparasites, such as Phthirus pubis and Demodex.

  7. Growth factor stimulation improves the structure and properties of scaffold-free engineered auricular cartilage constructs.

    Directory of Open Access Journals (Sweden)

    Renata G Rosa

    Full Text Available The reconstruction of the external ear to correct congenital deformities or repair following trauma remains a significant challenge in reconstructive surgery. Previously, we have developed a novel approach to create scaffold-free, tissue engineering elastic cartilage constructs directly from a small population of donor cells. Although the developed constructs appeared to adopt the structural appearance of native auricular cartilage, the constructs displayed limited expression and poor localization of elastin. In the present study, the effect of growth factor supplementation (insulin, IGF-1, or TGF-β1 was investigated to stimulate elastogenesis as well as to improve overall tissue formation. Using rabbit auricular chondrocytes, bioreactor-cultivated constructs supplemented with either insulin or IGF-1 displayed increased deposition of cartilaginous ECM, improved mechanical properties, and thicknesses comparable to native auricular cartilage after 4 weeks of growth. Similarly, growth factor supplementation resulted in increased expression and improved localization of elastin, primarily restricted within the cartilaginous region of the tissue construct. Additional studies were conducted to determine whether scaffold-free engineered auricular cartilage constructs could be developed in the 3D shape of the external ear. Isolated auricular chondrocytes were grown in rapid-prototyped tissue culture molds with additional insulin or IGF-1 supplementation during bioreactor cultivation. Using this approach, the developed tissue constructs were flexible and had a 3D shape in very good agreement to the culture mold (average error <400 µm. While scaffold-free, engineered auricular cartilage constructs can be created with both the appropriate tissue structure and 3D shape of the external ear, future studies will be aimed assessing potential changes in construct shape and properties after subcutaneous implantation.

  8. The bigger, the better? Volume measurements of parasites and hosts: Parasitic barnacles (Cirripedia, Rhizocephala and their decapod hosts.

    Directory of Open Access Journals (Sweden)

    Christina Nagler

    Full Text Available Rhizocephala, a group of parasitic castrators of other crustaceans, shows remarkable morphological adaptations to their lifestyle. The adult female parasite consists of a body that can be differentiated into two distinct regions: a sac-like structure containing the reproductive organs (the externa, and a trophic, root like system situated inside the hosts body (the interna. Parasitism results in the castration of their hosts, achieved by absorbing the entire reproductive energy of the host. Thus, the ratio of the host and parasite sizes is crucial for the understanding of the parasite's energetic cost. Using advanced imaging methods (micro-CT in conjunction with 3D modeling, we measured the volume of parasitic structures (externa, interna, egg mass, egg number, visceral mass and the volume of the entire host. Our results show positive correlations between the volume of (1 entire rhizocephalan (externa + interna and host body, (2 rhizocephalan externa and host body, (3 rhizocephalan visceral mass and rhizocephalan body, (4 egg mass and rhizocephalan externa, (5 rhizocephalan egg mass and their egg number. Comparing the rhizocephalan Sylon hippolytes, a parasite of caridean shrimps, and representatives of Peltogaster, parasites of hermit crabs, we could match their different traits on a reconstructed relationship. With this study we add new and significant information to our global understanding of the evolution of parasitic castrators, of interactions between a parasitic castrator and its host and of different parasitic strategies within parasitic castrators exemplified by rhizocephalans.

  9. Growth Factor Stimulation Improves the Structure and Properties of Scaffold-Free Engineered Auricular Cartilage Constructs

    Science.gov (United States)

    Rosa, Renata G.; Joazeiro, Paulo P.; Bianco, Juares; Kunz, Manuela; Weber, Joanna F.; Waldman, Stephen D.

    2014-01-01

    The reconstruction of the external ear to correct congenital deformities or repair following trauma remains a significant challenge in reconstructive surgery. Previously, we have developed a novel approach to create scaffold-free, tissue engineering elastic cartilage constructs directly from a small population of donor cells. Although the developed constructs appeared to adopt the structural appearance of native auricular cartilage, the constructs displayed limited expression and poor localization of elastin. In the present study, the effect of growth factor supplementation (insulin, IGF-1, or TGF-β1) was investigated to stimulate elastogenesis as well as to improve overall tissue formation. Using rabbit auricular chondrocytes, bioreactor-cultivated constructs supplemented with either insulin or IGF-1 displayed increased deposition of cartilaginous ECM, improved mechanical properties, and thicknesses comparable to native auricular cartilage after 4 weeks of growth. Similarly, growth factor supplementation resulted in increased expression and improved localization of elastin, primarily restricted within the cartilaginous region of the tissue construct. Additional studies were conducted to determine whether scaffold-free engineered auricular cartilage constructs could be developed in the 3D shape of the external ear. Isolated auricular chondrocytes were grown in rapid-prototyped tissue culture molds with additional insulin or IGF-1 supplementation during bioreactor cultivation. Using this approach, the developed tissue constructs were flexible and had a 3D shape in very good agreement to the culture mold (average error tissue structure and 3D shape of the external ear, future studies will be aimed assessing potential changes in construct shape and properties after subcutaneous implantation. PMID:25126941

  10. Using game technologies to improve the safety of construction plant operations.

    Science.gov (United States)

    Guo, Hongling; Li, Heng; Chan, Greg; Skitmore, Martin

    2012-09-01

    Many accidents occur world-wide in the use of construction plant and equipment, and safety training is considered by many to be one of the best approaches to their prevention. However, current safety training methods/tools are unable to provide trainees with the hands-on practice needed. Game technology-based safety training platforms have the potential to overcome this problem in a virtual environment. One such platform is described in this paper - its characteristics are analysed and its possible contribution to safety training identified. This is developed and tested by means of a case study involving three major pieces of construction plant, which successfully demonstrates that the platform can improve the process and performance of the safety training involved in their operation. This research not only presents a new and useful solution to the safety training of construction operations, but illustrates the potential use of advanced technologies in solving construction industry problems in general. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. The role of moulting in parasite defence.

    Science.gov (United States)

    Duneau, David; Ebert, Dieter

    2012-08-07

    Parasitic infections consist of a succession of steps during which hosts and parasites interact in specific manners. At each step, hosts can use diverse defence mechanisms to counteract the parasite's attempts to invade and exploit them. Of these steps, the penetration of parasites into the host is a key step for a successful infection and the epithelium is the first line of host defence. The shedding of this protective layer (moulting) is a crucial feature in the life cycle of several invertebrate and vertebrate taxa, and is generally considered to make hosts vulnerable to parasites and predators. Here, we used the crustacean Daphnia magna to test whether moulting influences the likelihood of infection by the castrating bacterium Pasteuria ramosa. This parasite is known to attach to the host cuticula before penetrating into its body. We found that the likelihood of successful parasite infection is greatly reduced if the host moults within 12 h after parasite exposure. Thus, moulting is beneficial for the host being exposed to this parasite. We further show that exposure to the parasite does not induce hosts to moult earlier. We discuss the implications of our findings for host and parasite evolution and epidemiology.

  12. RNA trafficking in parasitic plant systems

    Science.gov (United States)

    LeBlanc, Megan; Kim, Gunjune; Westwood, James H.

    2012-01-01

    RNA trafficking in plants contributes to local and long-distance coordination of plant development and response to the environment. However, investigations of mobile RNA identity and function are hindered by the inherent difficulty of tracing a given molecule of RNA from its cell of origin to its destination. Several methods have been used to address this problem, but all are limited to some extent by constraints associated with accurately sampling phloem sap or detecting trafficked RNA. Certain parasitic plant species form symplastic connections to their hosts and thereby provide an additional system for studying RNA trafficking. The haustorial connections of Cuscuta and Phelipanche species are similar to graft junctions in that they are able to transmit mRNAs, viral RNAs, siRNAs, and proteins from the host plants to the parasite. In contrast to other graft systems, these parasites form connections with host species that span a wide phylogenetic range, such that a high degree of nucleotide sequence divergence may exist between host and parasites and allow confident identification of most host RNAs in the parasite system. The ability to identify host RNAs in parasites, and vice versa, will facilitate genomics approaches to understanding RNA trafficking. This review discusses the nature of host–parasite connections and the potential significance of host RNAs for the parasite. Additional research on host–parasite interactions is needed to interpret results of RNA trafficking studies, but parasitic plants may provide a fascinating new perspective on RNA trafficking. PMID:22936942

  13. RNA trafficking in parasitic plant systems

    Directory of Open Access Journals (Sweden)

    Megan L LeBlanc

    2012-08-01

    Full Text Available RNA trafficking in plants contributes to local and long-distance coordination of plant development and response to the environment. However, investigations of mobile RNA identity and function are hindered by the inherent difficulty of tracing a given molecule of RNA from its cell of origin to its destination. Several methods have been used to address this problem, but all are limited to some extent by constraints associated with accurately sampling phloem sap or detecting trafficked RNA. Certain parasitic plant species form symplastic connections to their hosts and thereby provide an additional system for studying RNA trafficking. The haustorial connections of Cuscuta and Phelipanche species are similar to graft junctions in that they are able to transmit mRNAs, viral RNAs, siRNAs and proteins from the host plants to the parasite. In contrast to other graft systems, these parasites form connections with host species that span a wide phylogenetic range, such that a high degree of nucleotide sequence divergence may exist between host and parasites and allow confident identification of most host RNAs in the parasite system. The ability to identify host RNAs in parasites, and vice versa, will facilitate genomics approaches to understanding RNA trafficking. This review discusses the nature of host parasite connections and the potential significance of host RNAs for the parasite. Additional research on host-parasite interactions is needed to interpret results of RNA trafficking studies, but parasitic plants may provide a fascinating new perspective on RNA trafficking.

  14. Maternal androgens in avian brood parasites and their hosts: responses to parasitism and competition?

    Science.gov (United States)

    Hahn, Caldwell; Wingfield, John C.; Fox, David M.; Walker, Brian G.; Thomley, Jill E

    2017-01-01

    In the coevolutionary dynamic of avian brood parasites and their hosts, maternal (or transgenerational) effects have rarely been investigated. We examined the potential role of elevated yolk testosterone in eggs of the principal brood parasite in North America, the brown-headed cowbird, and three of its frequent host species. Elevated maternal androgens in eggs are a common maternal effect observed in many avian species when breeding conditions are unfavorable. These steroids accelerate embryo development, shorten incubation period, increase nestling growth rate, and enhance begging vigor, all traits that can increase the survival of offspring. We hypothesized that elevated maternal androgens in host eggs are a defense against brood parasitism. Our second hypothesis was that elevated maternal androgens in cowbird eggs are a defense against intra-specific competition. For host species, we found that elevated yolk testosterone was correlated with parasitized nests of small species, those whose nest success is most reduced by cowbird parasitism. For cowbirds, we found that elevated yolk testosterone was correlated with eggs in multiply-parasitized nests, which indicate intra-specific competition for nests due to high cowbird density. We propose experimental work to further examine the use of maternal effects by cowbirds and their hosts.

  15. Women and Parasitic Diseases

    Science.gov (United States)

    ... Consultations, and General Public. Contact Us Parasites Home Women Recommend on Facebook Tweet Share Compartir Infection with ... of parasites can lead to unique consequences for women. Some examples are given below. Infection with Toxoplasma ...

  16. Design improvements, construction and operating experience with BWRs in Japan

    International Nuclear Information System (INIS)

    Uchigasaki, G.; Yokomi, M.; Sasaki, M.; Aoki, R.; Hashimoto, H.

    1983-01-01

    (1) The first domestic-made 1100-MW(e) BWR in Japan commenced commercial operation in April 1982. The unit is the leading one of the subsequent three in Fukushima Daini nuclear power station owned by the Tokyo Electric Power Company Inc. (Tepco). Based on the accumulated construction and operation experience of 500-MW(e) and 800-MW(e) class BWRs, improvements in various aspects during both the design and construction stages were introduced in core and fuel design with advanced gadolinia distribution, reactor feedwater treatment technology for crud reduction, a radwaste island, control and instrumentation to cope with the lessons learned through Three Mile Island assessment etc. (2) Based on many operating experiences with BWRs, an improved BWR core, which has easier operability and higher load factor than the conventional core, has been developed. The characteristic of the improved core is ''axially two-zoned uranium enrichment distribution''; the enrichment of the upper part of the fuel is slightly higher than that of the lower part. Through the improved core it became possible to optimize the axial power flattening and core reactivity control separately by axial enrichment distribution and burnable poison content. The improved fuels were loaded into operating BWRs and successfully proved the performance by this experience. (3) To shorten annual outage time, to reduce radiation exposure, to save manpower, and to achieve high reliability and safety of inspection operation, the remote automatic service and inspection equipment were developed in Japan. This paper presents the concept, distinctive features, and actual operation experience of the automatic refuelling machine, control-rod drive (CRD) remote-handling machine, improved main steam line isolation plug, and the automated ultrasonic inspection system with a computerized data processing unit, which have been developed by Hitachi, Ltd. with excellent results. (author)

  17. Anti-inflammatory effects of exercise

    DEFF Research Database (Denmark)

    Pedersen, Bente Klarlund

    2017-01-01

    and IL-10 is provoked by exercise and exerts direct anti-inflammatory effects by an inhibition of TNF-α and by stimulating IL-1ra, thereby limiting IL-1β signalling. Moreover, muscle-derived IL-6 appears to have direct anti-inflammatory effects and serves as a mechanism to improve glucose tolerance....... In addition, indirect anti-inflammatory effects of long-term exercise are mediated via improvements in body composition. CONCLUSION: Physical activity represents a natural, strong anti-inflammatory strategy with minor side effects and should be integrated in the management of patients with cardiometabolic...

  18. Anti-leishmanial and toxicity activities of some selected Iranian medicinal plants.

    Science.gov (United States)

    Kheiri Manjili, Hamidreza; Jafari, Hamidreza; Ramazani, Ali; Davoudi, Noushin

    2012-11-01

    Leishmaniasis is caused by protozoan parasites belonging to the genus Leishmania. Cutaneous leishmaniasis is the most common form of leishmaniasis in Iran. As there is not any vaccine for leishmaniasis, treatment is important to prevent the spreading of parasites. There is, therefore, a need to develop newer drugs from different sources. The aim of this study was to assess anti-leishmanial activity of the ethanolic extracts of 17 different medicinal plants against Leishmania major promastigotes and macrophage cell line J774. The selection of the hereby studied 17 plants was based on the existing information on their local ethnobotanic history. Plants were dried, powdered, and macerated in a hydroalcoholic solution. Resulting extracts have been assessed for in vitro anti-leishmanial and brine shrimp toxicity activities. Four plants, Caesalpinia gilliesii, Satureia hortensis, Carum copticum heirm, and Thymus migricus, displayed high anti-leishmanial activity (IC50, 9.76 ± 1.27, 15.625 ± 3.76, 15.625 ± 5.46, and 31.25 ± 15.44 μM, respectively) and were toxic against the J774 macrophage cell line at higher concentrations than those needed to inhibit the parasite cell growth (IC50, 45.13 ± 3.17, 100.44 ± 17.48, 43.76 ± 0.78, and 39.67 ± 3.29 μM, respectively). Glucantime as positive control inhibited the growth of L. major promastigotes with IC50 = 254 μg/ml on promastigotes (1 × 10(6)/100 μ/well) of a log phase culture, without affecting the growth of J774 macrophages. These data revealed that C. gilliesii, S. hortensis, C. copticum heirm, and T. migricus extracts contain active compounds, which could serve as alternative agents in the control of cutaneous leishmaniasis. The activity of these herbs against L. major promastigotes and macrophage cell line J774 was reported for the first time in our study.

  19. RECOMBINANT ANTI-TENASCIN ANTIBODY CONTRUCTS

    International Nuclear Information System (INIS)

    ZALUTSKY, MICHAEL R.

    2006-01-01

    The general objective of this research is to combine genetically derived molecular constructs reactive with tenascin, with appropriate radionuclides and labeling methods in order to generate more effective diagnostic and therapeutic reagents for oncologic nuclear medicine. Tenascin, a polymorphic extracellular matrix glycoprotein, is of interest because of its high expression on glioma, melanoma, as well as prostate and breast carcinoma. Recently, we have also documented high levels of tenascin in lymphomas, particularly those of higher grade, making the potential clinical impact of tenascin-specific radiodiagnostics and therapeutics even greater. An essential feature of our work plan is the ability to exploit our extensive clinical experience in order to design second-generation constructs with properties which could improve clinical efficacy. To date, we have treated over 150 brain tumor patients with 131I-labeled murine 81C6, an antibody which binds specifically to the alternatively spliced fibronectin type III repeats CD of the tenascin molecule. During the current grant period, we have made several observations which form the basis for our proposed specific aims. First, tissue distribution and catabolism experiments in animal models have demonstrated enhanced stability for a chimeric construct composed of murine variable regions and human IgG2 constant domains. Furthermore, pharmacokinetic studies in patients with 131I-labeled chimeric 81C6 have shown significantly longer retention in glioma tumor resection cavities compared with its murine parent. Second, we have initiated the first clinical trial of an endoradiotherapeutic labeled with the 7.2-hr ?-particle emitter 211At. Twelve glioma patients have received 211At-labeled chimeric 81C6 directly into their brain tumor resection cavity, and very encouraging results have been obtained. Now that the feasibility of human studies with 211At, has been demonstrated, the development and evaluation of anti

  20. Epidemiological models for the spread of anti-malarial resistance

    Directory of Open Access Journals (Sweden)

    Antia R

    2003-02-01

    Full Text Available Abstract Background The spread of drug resistance is making malaria control increasingly difficult. Mathematical models for the transmission dynamics of drug sensitive and resistant strains can be a useful tool to help to understand the factors that influence the spread of drug resistance, and they can therefore help in the design of rational strategies for the control of drug resistance. Methods We present an epidemiological framework to investigate the spread of anti-malarial resistance. Several mathematical models, based on the familiar Macdonald-Ross model of malaria transmission, enable us to examine the processes and parameters that are critical in determining the spread of resistance. Results In our simplest model, resistance does not spread if the fraction of infected individuals treated is less than a threshold value; if drug treatment exceeds this threshold, resistance will eventually become fixed in the population. The threshold value is determined only by the rates of infection and the infectious periods of resistant and sensitive parasites in untreated and treated hosts, whereas the intensity of transmission has no influence on the threshold value. In more complex models, where hosts can be infected by multiple parasite strains or where treatment varies spatially, resistance is generally not fixed, but rather some level of sensitivity is often maintained in the population. Conclusions The models developed in this paper are a first step in understanding the epidemiology of anti-malarial resistance and evaluating strategies to reduce the spread of resistance. However, specific recommendations for the management of resistance need to wait until we have more data on the critical parameters underlying the spread of resistance: drug use, spatial variability of treatment and parasite migration among areas, and perhaps most importantly, cost of resistance.

  1. Evaluation of parasitic contamination in consuming vegetables in a city of Iran in 2011

    Directory of Open Access Journals (Sweden)

    Neda Mehrnejat

    2015-01-01

    Conclusion: The study showed that the percentage of parasites in raw vegetables was close to zero. However, the previous study in Isfahan city reported 13% contamination. The reduction in intestinal worm infections is probably the result of development of water and wastewater networks, improvement in public health and public knowledge about parasitic infections and different ways of its prevention.

  2. Some problems of NPP construction base improvement

    International Nuclear Information System (INIS)

    Movchan, S.V.

    1984-01-01

    NPP construction bases are characterized by high cost of construction and large area. Duration of base construction makes up 3-4 years, labour contents for their erection constitute 600-900 thousand man-days. Delays in organizing functional base services essentially decelerate construction rates of the main NPP buildings. Maximum joining of separate buildings by their functional assignment and structural peculiarities, wide application of container buildings, partial utilization of permanent buildings of production centre for construction needs; transition to new organizational form of construction based on industrial production of buildings; production of volumetric structural-technological cells with mounted equipment manufactured at specialized plants, mounting NPP components with stock produced cells, consideration of the problem of large power centre creation are necessary for reduction of construction centres, area reduction of cost and duration of their construction

  3. Smart Parasitic Nematodes Use Multifaceted Strategies to Parasitize Plants

    Directory of Open Access Journals (Sweden)

    Muhammad A. Ali

    2017-10-01

    Full Text Available Nematodes are omnipresent in nature including many species which are parasitic to plants and cause enormous economic losses in various crops. During the process of parasitism, sedentary phytonematodes use their stylet to secrete effector proteins into the plant cells to induce the development of specialized feeding structures. These effectors are used by the nematodes to develop compatible interactions with plants, partly by mimicking the expression of host genes. Intensive research is going on to investigate the molecular function of these effector proteins in the plants. In this review, we have summarized which physiological and molecular changes occur when endoparasitic nematodes invade the plant roots and how they develop a successful interaction with plants using the effector proteins. We have also mentioned the host genes which are induced by the nematodes for a compatible interaction. Additionally, we discuss how nematodes modulate the reactive oxygen species (ROS and RNA silencing pathways in addition to post-translational modifications in their own favor for successful parasitism in plants.

  4. How Can Lean Construction Improve the Daily Schedule of A Construction Manager?

    Science.gov (United States)

    Binninger, Marco; Dlouhy, Janosch; Schneider, Johannes; Haghsheno, Shervin

    2017-10-01

    The outcome of construction projects highly depends on effective management. The site manager is responsible for the site, and has a key role in executing construction projects. Especially this position has a wide range of tasks and a high volume of workload, which has to be carried out in a high pressure and high stress environment. Chaotic construction processes often create these working conditions. Lean Construction can help to organize the construction site in a better way and automatically supports the site manager.

  5. Nuclear hormone receptors in parasitic helminths

    OpenAIRE

    Wu, Wenjie; LoVerde, Philip T

    2010-01-01

    Nuclear receptors (NRs) belong to a large protein superfamily that are important transcriptional modulators in metazoans. Parasitic helminths include parasitic worms from the Lophotrochozoa (Platyhelminths) and Ecdysozoa (Nematoda). NRs in parasitic helminths diverged into two different evolutionary lineages. NRs in parasitic Platyhelminths have orthologues in Deuterostomes, in arthropods or both with a feature of extensive gene loss and gene duplication within different gene groups. NRs in p...

  6. A comprehensive evaluation of rodent malaria parasite genomes and gene expression

    KAUST Repository

    Otto, Thomas D

    2014-10-30

    Background: Rodent malaria parasites (RMP) are used extensively as models of human malaria. Draft RMP genomes have been published for Plasmodium yoelii, P. berghei ANKA (PbA) and P. chabaudi AS (PcAS). Although availability of these genomes made a significant impact on recent malaria research, these genomes were highly fragmented and were annotated with little manual curation. The fragmented nature of the genomes has hampered genome wide analysis of Plasmodium gene regulation and function. Results: We have greatly improved the genome assemblies of PbA and PcAS, newly sequenced the virulent parasite P. yoelii YM genome, sequenced additional RMP isolates/lines and have characterized genotypic diversity within RMP species. We have produced RNA-seq data and utilized it to improve gene-model prediction and to provide quantitative, genome-wide, data on gene expression. Comparison of the RMP genomes with the genome of the human malaria parasite P. falciparum and RNA-seq mapping permitted gene annotation at base-pair resolution. Full-length chromosomal annotation permitted a comprehensive classification of all subtelomeric multigene families including the `Plasmodium interspersed repeat genes\\' (pir). Phylogenetic classification of the pir family, combined with pir expression patterns, indicates functional diversification within this family. Conclusions: Complete RMP genomes, RNA-seq and genotypic diversity data are excellent and important resources for gene-function and post-genomic analyses and to better interrogate Plasmodium biology. Genotypic diversity between P. chabaudi isolates makes this species an excellent parasite to study genotype-phenotype relationships. The improved classification of multigene families will enhance studies on the role of (variant) exported proteins in virulence and immune evasion/modulation.

  7. Prevalence of Parasitic Contamination

    Science.gov (United States)

    Ismail, Yazan

    2016-01-01

    One of the main ways in transmitting parasites to humans is through consuming contaminated raw vegetables. The aim of this study was to evaluate the prevalence of parasitological contamination (helminthes eggs, Giardia and Entamoeba histolytica cysts) of salad vegetables sold at supermarkets and street vendors in Amman and Baqa’a – Jordan. A total of 133 samples of salad vegetables were collected and examined for the prevalence of parasites. It was found that 29% of the samples were contaminated with different parasites. Of the 30 lettuce, 33 tomato, 42 parsley and 28 cucumber samples examined the prevalence of Ascaris spp. eggs was 43%, 15%, 21% and 4%; Toxocara spp. eggs was 30%, 0%, 0% and 4%; Giardia spp. cysts was 23%, 6%, 0% and 0%; Taenia/Echinococcus eggs was 20%, 0%, 5% and 0%; Fasciola hepatica eggs was 13%, 3%, 2% and 0%; and E. histolytica cysts was 10%, 6%, 0% and 0%, respectively. There was no significant difference in the prevalence of parasite in salad vegetables either between supermarkets and street vendors, or between Amman and Baqa’a, Ascaris spp. was found to be the highest prevalent parasite in salad vegetables from supermarkets and street vendors and from Amman and Baqa’a. Our results pointed out that, the parasitic contamination of salad vegetables found in our study might be caused by irrigating crops with faecal contaminated water. We concluded that salad vegetables sold in Amman and Baqa’a may cause a health risk to consumers.

  8. The dipteran parasitoid Exorista bombycis induces pro- and anti-oxidative reactions in the silkworm Bombyx mori: Enzymatic and genetic analysis.

    Science.gov (United States)

    Makwana, Pooja; Pradeep, Appukuttan Nair R; Hungund, Shambhavi P; Ponnuvel, Kangayam M; Trivedy, Kanika

    2017-02-01

    Hymenopteran parasitoids inject various factors including polydnaviruses along with their eggs into their host insects that suppress host immunity reactions to the eggs and larvae. Less is known about the mechanisms evolved in dipteran parasitoids that suppress host immunity. Here we report that the dipteran, Exorista bombycis, parasitization leads to pro-oxidative reactions and activation of anti-oxidative enzymes in the silkworm Bombyx mori larva. We recorded increased activity of oxidase, superoxide dismutase, thioredoxin peroxidase, catalase, glutathione-S-transferase (GST), and peroxidases in the hemolymph plasma, hemocytes, and fat body collected from B. mori after E. bombycis parasitization. Microarray and qPCR showed differential expression of genes encoding pro- and anti-oxidant enzymes in the hemocytes. The significance of this work lies in increased understanding of dipteran parasitoid biology. © 2017 Wiley Periodicals, Inc.

  9. Feasible introgression of an anti-pathogen transgene into an urban mosquito population without using gene-drive.

    Directory of Open Access Journals (Sweden)

    Kenichi W Okamoto

    2014-07-01

    Full Text Available Introgressing anti-pathogen constructs into wild vector populations could reduce disease transmission. It is generally assumed that such introgression would require linking an anti-pathogen gene with a selfish genetic element or similar technologies. Yet none of the proposed transgenic anti-pathogen gene-drive mechanisms are likely to be implemented as public health measures in the near future. Thus, much attention now focuses instead on transgenic strategies aimed at mosquito population suppression, an approach generally perceived to be practical. By contrast, aiming to replace vector competent mosquito populations with vector incompetent populations by releasing mosquitoes carrying a single anti-pathogen gene without a gene-drive mechanism is widely considered impractical.Here we use Skeeter Buster, a previously published stochastic, spatially explicit model of Aedes aegypti to investigate whether a number of approaches for releasing mosquitoes with only an anti-pathogen construct would be efficient and effective in the tropical city of Iquitos, Peru. To assess the performance of such releases using realistic release numbers, we compare the transient and long-term effects of this strategy with two other genetic control strategies that have been developed in Ae. aegypti: release of a strain with female-specific lethality, and a strain with both female-specific lethality and an anti-pathogen gene. We find that releasing mosquitoes carrying only an anti-pathogen construct can substantially decrease vector competence of a natural population, even at release ratios well below that required for the two currently feasible alternatives that rely on population reduction. Finally, although current genetic control strategies based on population reduction are compromised by immigration of wild-type mosquitoes, releasing mosquitoes carrying only an anti-pathogen gene is considerably more robust to such immigration.Contrary to the widely held view that

  10. Evaluation of a novel magneto-optical method for the detection of malaria parasites.

    Directory of Open Access Journals (Sweden)

    Agnes Orbán

    Full Text Available Improving the efficiency of malaria diagnosis is one of the main goals of current malaria research. We have recently developed a magneto-optical (MO method which allows high-sensitivity detection of malaria pigment (hemozoin crystals in blood via the magnetically induced rotational motion of the hemozoin crystals. Here, we evaluate this MO technique for the detection of Plasmodium falciparum in infected erythrocytes using in-vitro parasite cultures covering the entire intraerythrocytic life cycle. Our novel method detected parasite densities as low as ∼ 40 parasites per microliter of blood (0.0008% parasitemia at the ring stage and less than 10 parasites/µL (0.0002% parasitemia in the case of the later stages. These limits of detection, corresponding to approximately 20 pg/µL of hemozoin produced by the parasites, exceed that of rapid diagnostic tests and compete with the threshold achievable by light microscopic observation of blood smears. The MO diagnosis requires no special training of the operator or specific reagents for parasite detection, except for an inexpensive lysis solution to release intracellular hemozoin. The devices can be designed to a portable format for clinical and in-field tests. Besides testing its diagnostic performance, we also applied the MO technique to investigate the change in hemozoin concentration during parasite maturation. Our preliminary data indicate that this method may offer an efficient tool to determine the amount of hemozoin produced by the different parasite stages in synchronized cultures. Hence, it could eventually be used for testing the susceptibility of parasites to antimalarial drugs.

  11. Parasitic Contamination of Raw Vegetables in Zanjan Markets, Iran

    Directory of Open Access Journals (Sweden)

    Negin Torabi

    2016-09-01

    Full Text Available Background: Complex surface of vegetables facilitate attachment and transmission of several pathogens. No previous study has been conducted in survey of parasitic contamination of vegetables in Zanjan. This study aimed to detect the parasitic contamination in common raw vegetables in Zanjan markets. Methods: A total of 352 raw vegetable samples, including leek, parsley, basil, mint, radish, cress and dill were collected from grocery stores using cluster sampling in different regions of the city during 2014. The edible parts of vegetables were separated and immersed in normal saline solution. Floating vegetables were removed and the solution was allowed to sediment at room temperature for 24 hours. The pellet was examined following sedimentation and floatation methods. Results:Various Organisms were detected in 54% (190 of the 352 samples, but only 2.8% of samples had pathogenic parasites including; Trichostrongylus eggs (3, Hookworm eggs (2, Eimeria oocysts (2, Sarcocystis oocyst (1, Strongyloides larvae (1, and Fasciola eggs (1. The contamination rate of vegetables was highest (90.4% in the fall (p˂0.05. Conclusion: Vegetable contamination with parasitic organisms in this area was low, maybe due to irrigation of vegetables with sources other than sewage water, but it is still necessary to improve sanitary conditions of vegetables.

  12. Improving construction performance

    International Nuclear Information System (INIS)

    1990-03-01

    Design for Constructability's overall purpose was to identify and address changes in the nuclear industry to restore nuclear energy as an attractive option for new generating capacity. As the centerpiece of project control, a comprehensive, stable schedule should organize the project logically to accomplish the project's objectives. A good schedule will: integrate the project team; serve as a communications tool to all members of the project team; and provide a means to monitor and measure project performance

  13. Development of a fast agglutination screening test (FAST) for the detection of anti-Leishmania antibodies in dogs

    NARCIS (Netherlands)

    Schallig, H. D. F. H.; Schoone, G. J.; Beijer, E. G. M.; Kroon, C. C. M.; Hommers, M.; Ozbel, Y.; Ozensoy, S.; da Silva, E. S.; Cardoso, L. M.; da Silva, E. D.

    2002-01-01

    A fast agglutination screening test (FAST) for the detection of anti-Leishinania antibodies in serum samples from dogs with visceral leishmamosis was developed. The test is based on the direct agglutination test (DAT), but combines a higher parasite concentration with a smaller test volume. In

  14. Anti-3D Weapon Model Detection for Safe 3D Printing Based on Convolutional Neural Networks and D2 Shape Distribution

    Directory of Open Access Journals (Sweden)

    Giao N. Pham

    2018-03-01

    Full Text Available With the development of 3D printing, weapons are easily printed without any restriction from the production managers. Therefore, anti-3D weapon model detection is necessary issue in safe 3D printing to prevent the printing of 3D weapon models. In this paper, we would like to propose an anti-3D weapon model detection algorithm to prevent the printing of anti-3D weapon models for safe 3D printing based on the D2 shape distribution and an improved convolutional neural networks (CNNs. The purpose of the proposed algorithm is to detect anti-3D weapon models when they are used in 3D printing. The D2 shape distribution is computed from random points on the surface of a 3D weapon model and their geometric features in order to construct a D2 vector. The D2 vector is then trained by improved CNNs. The CNNs are used to detect anti-3D weapon models for safe 3D printing by training D2 vectors which have been constructed from the D2 shape distribution of 3D weapon models. Experiments with 3D weapon models proved that the D2 shape distribution of 3D weapon models in the same class is the same. Training and testing results also verified that the accuracy of the proposed algorithm is higher than the conventional works. The proposed algorithm is applied in a small application, and it could detect anti-3D weapon models for safe 3D printing.

  15. Introduction of New Parasites in Denmark

    DEFF Research Database (Denmark)

    Enemark, Heidi L.

    examples of such parasites/parasitic diseases: Setaria tundra, a mosquito-borne filarioid nematode which was detected for the first time in Danish deer in 2010. This parasite is usually considered harmless but is capable of causing peritonitis and mortality in ungulates. The newly detected parasite...... was genetically very similar to previously published isolates from France and Italy, and may have been spread to Denmark from southern Europe. Giardia spp. a zoonotic, unicellular parasite (protozoa) well known in Danish livestock but recently found in extremely high numbers in Danish deer with chronic diarrhea...... for the first time in Denmark approximately 10 years ago in 3 foxes from the Copenhagen area. Since then, no systematic surveillance has been performed, and therefore the current prevalence among wildlife and pets is unknown. So far the parasite has not been found in intermediate hosts (rodents) in Denmark...

  16. Prevalence of intestinal parasites in three socioeconomically-different regions of Sivas, Turkey.

    Science.gov (United States)

    Celiksöz, Ali; Güler, Nuran; Güler, Güngör; Oztop, A Yasemin; Degerli, Serpil

    2005-06-01

    The study was carried out to determine the prevalence of parasites in three socioeconomically-different regions (Alibaba, Esentepe, and Cayboyu) of Sivas, Turkey, to determine the most accurate method for the diagnosis of taeniasis and enterobiasis, to determine the importance of household visits in primary healthcare to control parasitic diseases, and to treat intestinal parasitic diseases in those regions. Both stool specimens and cellophane tape (CT) samples were taken from 1,864 participants during 641 household visits in the three regions. The age groups included were pre-school [(0-6 year(s)], primary school (7-15 years), and the upper age group (16 years and above). The total prevalence of intestinal parasites in the three regions was 37.2%. Eleven intestinal parasite species were detected in both stool specimens and CT samples. Giardia intestinalis and Enterobius vermicularis were the most frequent species identified in all the three regions. Region I (Alibaba) had a higher prevalence of parasites compared to the other two regions. There was no significant difference between Region II (Esentepe) and Region III (Cayboyu) in isolation of intestinal parasites. There were statistically significant differences between the age groups when the rates of parasitic infection were compared. The highest prevalence of parasitosis was observed among the age group of 7-15 years and in the socioeconomically lowest one of the three regions. While the most accurate way of diagnosis for taeniasis was the combined usage of the CT and direct preparation methods, the CT method was the best method for the diagnosis of enterobiasis. Thus, the local administrators in cities need to pay more attention to the prevention of parasitic infections along with improvements in educational, environmental and sanitary conditions.

  17. Detection of short-term anomaly using parasitic discrete wavelet transform

    International Nuclear Information System (INIS)

    Nagamatsu, Takashi; Gofuku, Akio

    2013-01-01

    A parasitic discrete wavelet transform (P-DWT) that has a large flexibility in design of the mother wavelet (MW) and a high processing speed was applied for simulation and measured anomalies. First, we applied the P-DWT to detection of the short-term anomalies. Second, we applied the P-DWT to detection of the collision of pump using the pump diagnostic experiment equipment that was designed taking into consideration the structure of the pump used for the water-steam system of the fast breeder reactor 'Monju'. The vibration signals were measured by the vibration sensor attached to the pump when injecting four types of small objects (sphere, small sphere, cube, and rectangular parallelepiped). Anomaly detection was performed by calculating the fast wavelet instantaneous correlation using the parasitic filter that was constructed on the basis of the measured signals. The results suggested that the anomalies could be detected for all types of the supposed anomalies. (author)

  18. [Advances in researches on mechanism of anti-Toxoplasma Chinese herbal medicine].

    Science.gov (United States)

    Yu, Zhao-Yun; Zhang, Bao-de; Ning, Jun-ya; Wang, Yuan-yuan; Yuan, Wen-ying

    2015-10-01

    Toxoplasma gondii is an opportunity cellular parasite, related to the infection of various animals and human beings and severely impairing agriculture and human health. Because of the complexity of T. gondii life cycle, its different biological characteristics, and multifarious pathogenesis, there are no specific treatment and preventive medicines at present. Chinese herbal medicine can balance "yin-yang" and regulate the immunity and its side-effect is slight. Now, it has been a hot topic of the research on effective and secure medicines in anti-toxoplasmosis. This paper summarizes and analyzes the curative effect and mechanism of anti-Toxoplasma Chinese herbal medicine, such as Scutellaria baicalensis, Inontus obliquus polysaccharide, Radix glycyrrhizae, pumpkin seeds, and Semen arecae.

  19. Nutrition and metabolism of parasitized and non-parasitized ruminants. Some approaches for studying the mode of action of parasites

    International Nuclear Information System (INIS)

    Leng, R.A.

    1981-01-01

    The effects of helminth infections on ruminant digestive function and metabolism are discussed against the background of current information on the mechanisms controlling feed intake and utilization in normal animals. Although parasites reduce productivity by impairing appetite and utilization of nutrients, few studies have been conducted on the function of the digestive tract and the metabolism of parasitized animals. Those areas which warrant further investigation are described, and the techniques which could be usefully applied are outlined. It is concluded that more emphasis should be given to the diet available to parasitized animals, and that by using diets of different digestibility and protein content, valuable information could be obtained as to the relative importance of reduced appetite and reduced efficiency of feed utilization. Central to all studies is a proper delineation of the fate of proteins in the small intestine of parasitized animals, and characterization of the types of bacteria in the gut and their effects on endogenous protein losses. The application of 15 N is mentioned. The potential usefulness of 14 C (eg. to measure the flow of digesta, to the lower digestive tract; clearance of 14 C-propionate from blood; etc.) is described

  20. Host Diet Affects the Morphology of Monarch Butterfly Parasites.

    Science.gov (United States)

    Hoang, Kevin; Tao, Leiling; Hunter, Mark D; de Roode, Jacobus C

    2017-06-01

    Understanding host-parasite interactions is essential for ecological research, wildlife conservation, and health management. While most studies focus on numerical traits of parasite groups, such as changes in parasite load, less focus is placed on the traits of individual parasites such as parasite size and shape (parasite morphology). Parasite morphology has significant effects on parasite fitness such as initial colonization of hosts, avoidance of host immune defenses, and the availability of resources for parasite replication. As such, understanding factors that affect parasite morphology is important in predicting the consequences of host-parasite interactions. Here, we studied how host diet affected the spore morphology of a protozoan parasite ( Ophryocystis elektroscirrha ), a specialist parasite of the monarch butterfly ( Danaus plexippus ). We found that different host plant species (milkweeds; Asclepias spp.) significantly affected parasite spore size. Previous studies have found that cardenolides, secondary chemicals in host plants of monarchs, can reduce parasite loads and increase the lifespan of infected butterflies. Adding to this benefit of high cardenolide milkweeds, we found that infected monarchs reared on milkweeds of higher cardenolide concentrations yielded smaller parasites, a potentially hidden characteristic of cardenolides that may have important implications for monarch-parasite interactions.

  1. A review on fatigue life prediction methods for anti-vibration rubber materials

    Directory of Open Access Journals (Sweden)

    Xiaoli WANG

    2016-08-01

    Full Text Available Anti-vibration rubber, because of its superior elasticity, plasticity, waterproof and trapping characteristics, is widely used in the automotive industry, national defense, construction and other fields. The theory and technology of predicting fatigue life is of great significance to improve the durability design and manufacturing of anti-vibration rubber products. According to the characteristics of the anti-vibration rubber products in service, the technical difficulties for analyzing fatigue properties of anti-vibration rubber materials are pointed out. The research progress of the fatigue properties of rubber materials is reviewed from three angles including methods of fatigue crack initiation, fatigue crack propagation and fatigue damage accumulation. It is put forward that some nonlinear characteristics of rubber under fatigue loading, including the Mullins effect, permanent deformation and cyclic stress softening, should be considered in the further study of rubber materials. Meanwhile, it is indicated that the fatigue damage accumulation method based on continuum damage mechanics might be more appropriate to solve fatigue damage and life prediction problems for complex rubber materials and structures under fatigue loading.

  2. Parasite load induces progressive spleen architecture breakage and impairs cytokine mRNA expression in Leishmania infantum-naturally infected dogs.

    Science.gov (United States)

    Cavalcanti, Amanda S; Ribeiro-Alves, Marcelo; Pereira, Luiza de O R; Mestre, Gustavo Leandro; Ferreira, Anna Beatriz Robottom; Morgado, Fernanda N; Boité, Mariana C; Cupolillo, Elisa; Moraes, Milton O; Porrozzi, Renato

    2015-01-01

    Canine Visceral Leishmaniasis (CVL) shares many aspects with the human disease and dogs are considered the main urban reservoir of L. infantum in zoonotic VL. Infected dogs develop progressive disease with a large clinical spectrum. A complex balance between the parasite and the genetic/immunological background of the host are decisive for infection evolution and clinical outcome. This study comprised 92 Leishmania infected mongrel dogs of various ages from Mato Grosso, Brazil. Spleen samples were collected for determining parasite load, humoral response, cytokine mRNA expression and histopathology alterations. By real-time PCR for the ssrRNA Leishmania gene, two groups were defined; a low (lowP, n = 46) and a high parasite load groups (highP, n = 42). When comparing these groups, results show variable individual humoral immune response with higher specific IgG production in infected animals but with a notable difference in CVL rapid test optical densities (DPP) between highP and lowP groups. Splenic architecture disruption was characterized by disorganization of white pulp, more evident in animals with high parasitism. All cytokine transcripts in spleen were less expressed in highP than lowP groups with a large heterogeneous variation in response. Individual correlation analysis between cytokine expression and parasite load revealed a negative correlation for both pro-inflammatory cytokines: IFNγ, IL-12, IL-6; and anti-inflammatory cytokines: IL-10 and TGFβ. TNF showed the best negative correlation (r2 = 0.231; pdogs with high parasite load associated with a structural modification in the splenic lymphoid micro-architecture. We also discuss the possible mechanism responsible for the uncontrolled parasite growth and clinical outcome.

  3. Analysis of Resonance Response Performance of C-Band Antenna Using Parasitic Element

    Science.gov (United States)

    Islam, M. T.; Misran, N.; Mandeep, J. S.

    2014-01-01

    Analysis of the resonance response improvement of a planar C-band (4–8 GHz) antenna is proposed using parasitic element method. This parasitic element based method is validated for change in the active and parasitic antenna elements. A novel dual-band antenna for C-band application covering 5.7 GHz and 7.6 GHz is designed and fabricated. The antenna is composed of circular parasitic element with unequal microstrip lines at both sides and a rectangular partial ground plane. A fractional bandwidth of 13.5% has been achieved from 5.5 GHz to 6.3 GHz (WLAN band) for the lower band. The upper band covers from 7.1 GHz to 8 GHz with a fractional bandwidth of 12%. A gain of 6.4 dBi is achieved at the lower frequency and 4 dBi is achieved at the upper frequency. The VSWR of the antenna is less than 2 at the resonance frequency. PMID:24895643

  4. Parasites from the Past

    DEFF Research Database (Denmark)

    Søe, Martin Jensen; Fredensborg, Brian Lund; Nejsum, Peter

    will investigate how the diversity of food-borne parasitic infections has changed with cultural and dietary habits, hunting practice and intensity of animal husbandry. This is done by isolating and typing ancient DNA remains from parasite eggs found in archeological samples from across Denmark....

  5. INTESTINAL AND BLOOD PARASITES OF MAN IN TIMOR

    Directory of Open Access Journals (Sweden)

    W. Patrick Carney

    2012-09-01

    Full Text Available Survey tinja dan darah dipulau Timor guna menentukan distribusi dan prevalensi penyakit parasit diantara penduduk telah dilakukan pada bulan Juli dan Agustus tahun 1972 sebagai kelanjutan dari deretan survey yang dilakukan oleh Direktorat Jenderal Pencegahan Pemberantasan Penyakit menular Departemen Kesehatan, Bagian Parasitologi dan Pathologi Umum Fakultas Kedokteran Universitas Indonesia dan US Namru-2 di Indonesia. Sejumlah 445 sediaan tinja untuk pemeriksaan parasit usus, 581 sediaan darah untuk pemeriksaan parasit malaria dan 663 sediaan darah untuk pemeriksaan parasit filaria telah diambil dari penduduk cara merata di 7 desa pada 3 kabupaten di Timor, Nusa Tenggara Timur. Enam puluh delapan per cent diantara penduduk melihatkan satu atau lebih parasit usus didalam tinjanya dimana cacing tambang merupakan parasit usus yang terbanyak. Ascaris lumbricoides ketemukan jauh lebih kurang daripada di Jawa, Sumatra dan Sulawesi, juga diketemukan perbedaan itara "intestinal parasite rate" di Timor Indonesia dan Timor Portugis. Dua belas percent penduduk yang diperiksa melihatkan parasit malaria didalam darahnya sedangkan parasit filaria ditemukan sebanyak 8 percent. Plasmodium falciparum merupakan parasit malaria yang terbanyak ditemukan, ia jenis parasit fdaria yang ditemukan adalah "Timor microfilaria" dan Wuchereria bancrofti dimana yang pertama merupakan parasit yang terbanyak diantara penduduk yang diperiksa.

  6. Chytrid parasitism facilitates trophic transfer between bloom-forming cyanobacteria and zooplankton (Daphnia).

    Science.gov (United States)

    Agha, Ramsy; Saebelfeld, Manja; Manthey, Christin; Rohrlack, Thomas; Wolinska, Justyna

    2016-10-13

    Parasites are rarely included in food web studies, although they can strongly alter trophic interactions. In aquatic ecosystems, poorly grazed cyanobacteria often dominate phytoplankton communities, leading to the decoupling of primary and secondary production. Here, we addressed the interface between predator-prey and host-parasite interactions by conducting a life-table experiment, in which four Daphnia galeata genotypes were maintained on quantitatively comparable diets consisting of healthy cyanobacteria or cyanobacteria infected by a fungal (chytrid) parasite. In four out of five fitness parameters, at least one Daphnia genotype performed better on parasitised cyanobacteria than in the absence of infection. Further treatments consisting of purified chytrid zoospores and heterotrophic bacteria suspensions established the causes of improved fitness. First, Daphnia feed on chytrid zoospores which trophically upgrade cyanobacterial carbon. Second, an increase in heterotrophic bacterial biomass, promoted by cyanobacterial decay, provides an additional food source for Daphnia. In addition, chytrid infection induces fragmentation of cyanobacterial filaments, which could render cyanobacteria more edible. Our results demonstrate that chytrid parasitism can sustain zooplankton under cyanobacterial bloom conditions, and exemplify the potential of parasites to alter interactions between trophic levels.

  7. Early life stages of Northern shrimp (Pandalus borealis) are sensitive to fish feed containing the anti-parasitic drug diflubenzuron.

    Science.gov (United States)

    Bechmann, Renée Katrin; Lyng, Emily; Westerlund, Stig; Bamber, Shaw; Berry, Mark; Arnberg, Maj; Kringstad, Alfhild; Calosi, Piero; Seear, Paul J

    2018-05-01

    Increasing use of fish feed containing the chitin synthesis inhibiting anti-parasitic drug diflubenzuron (DFB) in salmon aquaculture has raised concerns over its impact on coastal ecosystems. Larvae of Northern shrimp (Pandalus borealis) were exposed to DFB medicated feed under Control conditions (7.0 °C, pH 8.0) and under Ocean Acidification and Warming conditions (OAW, 9.5 °C and pH 7.6). Two weeks' exposure to DFB medicated feed caused significantly increased mortality. The effect of OAW and DFB on mortality of shrimp larvae was additive; 10% mortality in Control, 35% in OAW, 66% in DFB and 92% in OAW + DFB. In OAW + DFB feeding and swimming activity were reduced for stage II larvae and none of the surviving larvae developed to stage IV. Two genes involved in feeding (GAPDH and PRLP) and one gene involved in moulting (DD9B) were significantly downregulated in larvae exposed to OAW + DFB relative to the Control. Due to a shorter intermoult period under OAW conditions, the OAW + DFB larvae were exposed throughout two instead of one critical pre-moult period. This may explain the more serious sub-lethal effects for OAW + DFB than DFB larvae. A single day exposure at 4 days after hatching did not affect DFB larvae, but high mortality was observed for OAW + DFB larvae, possibly because they were exposed closer to moulting. High mortality of shrimp larvae exposed to DFB medicated feed, indicates that the use of DFB in salmon aquaculture is a threat to crustacean zooplankton. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  8. One Health: parasites and beyond…

    OpenAIRE

    Blake, DP; Betson, ME

    2016-01-01

    The field of parasitism is broad, encompassing relationships between organisms where one benefits at the expense of another. Traditionally the discipline focuses on eukaryotes, with the study of bacteria and viruses complementary but distinct. Nonetheless, parasites vary in size and complexity from single celled protozoa, to enormous plants like those in the genus Rafflesia. Lifecycles range from obligate intracellular to extensive exoparasitism. Examples of parasites include high profile med...

  9. Pervasiveness of parasites in pollinators.

    Directory of Open Access Journals (Sweden)

    Sophie E F Evison

    Full Text Available Many pollinator populations are declining, with large economic and ecological implications. Parasites are known to be an important factor in the some of the population declines of honey bees and bumblebees, but little is known about the parasites afflicting most other pollinators, or the extent of interspecific transmission or vectoring of parasites. Here we carry out a preliminary screening of pollinators (honey bees, five species of bumblebee, three species of wasp, four species of hoverfly and three genera of other bees in the UK for parasites. We used molecular methods to screen for six honey bee viruses, Ascosphaera fungi, Microsporidia, and Wolbachia intracellular bacteria. We aimed simply to detect the presence of the parasites, encompassing vectoring as well as actual infections. Many pollinators of all types were positive for Ascosphaera fungi, while Microsporidia were rarer, being most frequently found in bumblebees. We also detected that most pollinators were positive for Wolbachia, most probably indicating infection with this intracellular symbiont, and raising the possibility that it may be an important factor in influencing host sex ratios or fitness in a diversity of pollinators. Importantly, we found that about a third of bumblebees (Bombus pascuorum and Bombus terrestris and a third of wasps (Vespula vulgaris, as well as all honey bees, were positive for deformed wing virus, but that this virus was not present in other pollinators. Deformed wing virus therefore does not appear to be a general parasite of pollinators, but does interact significantly with at least three species of bumblebee and wasp. Further work is needed to establish the identity of some of the parasites, their spatiotemporal variation, and whether they are infecting the various pollinator species or being vectored. However, these results provide a first insight into the diversity, and potential exchange, of parasites in pollinator communities.

  10. Enteric parasitic infections in HIV-infected patients with low CD4 counts in Toto, Nigeria

    International Nuclear Information System (INIS)

    Abaver, D.T.; Nwobegahay, J.M.; Goon, D.T.; Khoza, L.B

    2012-01-01

    Objectives: Enteric parasites are a major cause of diarrhoea in HIV/AIDS patients with low CD4 counts. Parasitic infections in HIV-infected individuals can reduce their quality of life and life span, especially those who are severely immunosuppressed with a CD4 T-lymphocyte count 0.05). Conclusions: Low CD4 counts in HIV-infected patients can lead to enteric infections. This information strengthens the importance of monitoring CD4 counts and intestinal parasites. Routine CD4 testing will greatly improve the prognosis of HIV positive patients. (author)

  11. Improved broadband and quasi-omnidirectional anti-reflection properties with biomimetic silicon nanostructures.

    Science.gov (United States)

    Huang, Yi-Fan; Chattopadhyay, Surojit; Jen, Yi-Jun; Peng, Cheng-Yu; Liu, Tze-An; Hsu, Yu-Kuei; Pan, Ci-Ling; Lo, Hung-Chun; Hsu, Chih-Hsun; Chang, Yuan-Huei; Lee, Chih-Shan; Chen, Kuei-Hsien; Chen, Li-Chyong

    2007-12-01

    Nature routinely produces nanostructured surfaces with useful properties, such as the self-cleaning lotus leaf, the colour of the butterfly wing, the photoreceptor in brittlestar and the anti-reflection observed in the moth eye. Scientists and engineers have been able to mimic some of these natural structures in the laboratory and in real-world applications. Here, we report a simple aperiodic array of silicon nanotips on a 6-inch wafer with a sub-wavelength structure that can suppress the reflection of light at a range of wavelengths from the ultraviolet, through the visible part of the spectrum, to the terahertz region. Reflection is suppressed for a wide range of angles of incidence and for both s- and p-polarized light. The antireflection properties of the silicon result from changes in the refractive index caused by variations in the height of the silicon nanotips, and can be simulated with models that have been used to explain the low reflection from moth eyes. The improved anti-reflection properties of the surfaces could have applications in renewable energy and electro-optical devices for the military.

  12. Anti-idiotypic antibodies as cancer vaccines: achievements and future improvements

    International Nuclear Information System (INIS)

    Ladjemi, Maha Z.

    2012-01-01

    Since the discovery of tumor-associated antigens (TAAs), researchers have tried to develop immune-based anti-cancer therapies. Thanks to their specificity, monoclonal antibodies (mAbs) offer the major advantage to induce fewer side effects than those caused by non-specific conventional treatments (e.g., chemotherapy, radiotherapy). Passive immunotherapy by means of mAbs or cytokines has proved efficacy in oncology and validated the use of immune-based agents as part of anti-cancer treatment options. The next step was to try to induce an active immune protection aiming to boost own’s host immune defense against TAAs. Cancer vaccines are thus developed to specifically induce active immune protection targeting only tumor cells while preserving normal tissues from a non-specific toxicity. But, as most of TAAs are self antigens, an immune tolerance against them exists representing a barrier to effective vaccination against these oncoproteins. One promising approach to break this immune tolerance consists in the use of anti-idiotypic (anti-Id) mAbs, so called Ab2, as antigen surrogates. This vaccination strategy allows also immunization against non-proteic antigens (such as carbohydrates). In some clinical studies, anti-Id cancer vaccines indeed induced efficient humoral and/or cellular immune responses associated with clinical benefit. This review article will focus on recent achievements of anti-Id mAbs use as cancer vaccines in solid tumors.

  13. Anti-trypanosomal activity of pentacyclic triterpenes isolated from Austroplenckia populnea (Celastraceae Atividade anti-tripanosomicida de triterpenes pentacíclicos isolados de Austroplenckia populnea (Celastraceae

    Directory of Open Access Journals (Sweden)

    Lucienir Pains DUARTE

    2002-04-01

    Full Text Available Four pentacyclic triterpenes isolated from Austroplenckia populnea and four compounds of known anti T. cruzi or anti-malarial activity were tested. Of those triterpenes tested 20alpha-hydroxy-tingenone showed high activity, epikatonic acid was less active, while populnilic and populninic acids were inactive against the trypanosome of the subgenus Schizotrypanum tested. Benzonidazole, nifurtimox, ketoconazole and primaquine presented a remarkable dose-dependent inhibitory effect reaching practically to a total growth inhibition of the parasite at the end of incubation time. The trypanosome tested appear to be a suitable model for preliminary screen for anti T. (S. cruzi compounds.Foram testados quatro triterpenos pentacíclicos isolados de Austroplenckia populnea e quatro compostos de conhecida atividade anti-T. cruzi ou anti-malárica. Dos triterpenos testados 20alfa-hidroxi-tingenona mostrou atividade elevada, ácido epicatônico foi menos ativo, enquanto ácido populnílico e populnínico foram inativos contra o tripanossoma do subgênero Schizotrypanum testado. Benzonidazole, nifurtimox, cetoconazole e primaquina apresentaram efeito inibitório dose-dependente atingindo praticamente a inibição total do crescimento do parasita no final do tempo de incubação. O tripanossoma testado mostrou ser um modelo adequado para uma seleção preliminar de compostos anti. T. (S. cruzi.

  14. Probability of Transmission of Malaria from Mosquito to Human Is Regulated by Mosquito Parasite Density in Naïve and Vaccinated Hosts.

    Directory of Open Access Journals (Sweden)

    Thomas S Churcher

    2017-01-01

    Full Text Available Over a century since Ronald Ross discovered that malaria is caused by the bite of an infectious mosquito it is still unclear how the number of parasites injected influences disease transmission. Currently it is assumed that all mosquitoes with salivary gland sporozoites are equally infectious irrespective of the number of parasites they harbour, though this has never been rigorously tested. Here we analyse >1000 experimental infections of humans and mice and demonstrate a dose-dependency for probability of infection and the length of the host pre-patent period. Mosquitoes with a higher numbers of sporozoites in their salivary glands following blood-feeding are more likely to have caused infection (and have done so quicker than mosquitoes with fewer parasites. A similar dose response for the probability of infection was seen for humans given a pre-erythrocytic vaccine candidate targeting circumsporozoite protein (CSP, and in mice with and without transfusion of anti-CSP antibodies. These interventions prevented infection more efficiently from bites made by mosquitoes with fewer parasites. The importance of parasite number has widespread implications across malariology, ranging from our basic understanding of the parasite, how vaccines are evaluated and the way in which transmission should be measured in the field. It also provides direct evidence for why the only registered malaria vaccine RTS,S was partially effective in recent clinical trials.

  15. Organizational changes of the daughter basal complex during the parasite replication of Toxoplasma gondii.

    Directory of Open Access Journals (Sweden)

    Ke Hu

    2008-01-01

    Full Text Available The apicomplexans are a large group of parasitic protozoa, many of which are important human and animal pathogens, including Plasmodium falciparum and Toxoplasma gondii. These parasites cause disease only when they replicate, and their replication is critically dependent on the proper assembly of the parasite cytoskeletons during cell division. In addition to their importance in pathogenesis, the apicomplexan parasite cytoskeletons are spectacular structures. Therefore, understanding the cytoskeletal biogenesis of these parasites is important not only for parasitology but also of general interest to broader cell biology. Previously, we found that the basal end of T. gondii contains a novel cytoskeletal assembly, the basal complex, a cytoskeletal compartment constructed in concert with the daughter cortical cytoskeleton during cell division. This study focuses on key events during the biogenesis of the basal complex using high resolution light microscopy, and reveals that daughter basal complexes are established around the duplicated centrioles independently of the structural integrity of the daughter cortical cytoskeleton, and that they are dynamic "caps" at the growing ends of the daughters. Compartmentation and polarization of the basal complex is first revealed at a late stage of cell division upon the recruitment of an EF-hand containing calcium binding protein, TgCentrin2. This correlates with the constriction of the basal complex, a process that can be artificially induced by increasing cellular calcium concentration. The basal complex is therefore likely to be a new kind of centrin-based contractile apparatus.

  16. A comprehensive evaluation of rodent malaria parasite genomes and gene expression

    KAUST Repository

    Otto, Thomas D; Bö hme, Ulrike; Jackson, Andrew P; Hunt, Martin; Franke-Fayard, Blandine; Hoeijmakers, Wieteke A M; Religa, Agnieszka A; Robertson, Lauren; Sanders, Mandy; Ogun, Solabomi A; Cunningham, Deirdre; Erhart, Annette; Billker, Oliver; Khan, Shahid M; Stunnenberg, Hendrik G; Langhorne, Jean; Holder, Anthony A; Waters, Andrew P; Newbold, Chris I; Pain, Arnab; Berriman, Matthew; Janse, Chris J

    2014-01-01

    Plasmodium biology. Genotypic diversity between P. chabaudi isolates makes this species an excellent parasite to study genotype-phenotype relationships. The improved classification of multigene families will enhance studies on the role of (variant) exported

  17. Improvement of design and construction technology in Japanese nuclear power plants

    International Nuclear Information System (INIS)

    Yomei Kato; Kiyoshi Shmizu

    1987-01-01

    Nuclear power generation currently offers economic merits superior to those of other methods dependant on such thermal power ganeration as petroleum, LNG, or coal. However, it is essential for the nuclear power generation continuously to retain economic superiority through concurently maintaining its high safety features and outstanding reliability. For achieving this purpose, taking into account of importance explained above, we have been developing and improving those of technologies such as design, engineering, and construction regarding the both field of management and techniques useful for plant construction. This paper covers the several instructive matters which Hitachi has accomplished throughout having had his hand in the project jobs. (author)

  18. Genetics of simple and complex host-parasite interactions

    International Nuclear Information System (INIS)

    Sidhu, G.S.; Webster, J.M.

    1977-01-01

    In nature a host plant can be viewed as a miniature replica of an ecological system where true and incidental parasites share the same habitat. Consequently, they influence each other's presence directly by interspecific interaction, and indirectly by inducing changes in the host's physiology and so form disease complexes. Since all physiological phenomena have their counterpart in the respective genetic systems of interacting organisms, valuable genetic information can be derived from the analysis of complex parasitic systems. Disease complexes may be classified according to the nature of interaction between various parasites on the same host. One parasite may nullify the host's resistance to another (e.g. Tomato - Meloidogyne incognita + Fusarium oxysporum lycopersici system). Conversely, a parasite may invoke resistance in the host against another parasite (e.g. Tomato - Fusarium oxysporum lycopersici + Verticillium albo atrum system). From the study of simple parasitic systems we know that resistance versus susceptibility against a single parasite is normally monogenically controlled. However, when more than one parasite interacts to invoke or nullify each other's responses on the same host plant, the genetic results suggest epistatic ratios. Nevertheless, epistatic ratios have been obtained also from simple parasitic systems owing to gene interaction. The epistatic ratios obtained from complex and simple parasitic systems are contrasted and compared. It is suggested that epistatic ratios obtained from simple parasitic systems may, in fact, be artifacts resulting from complex parasitic associations that often occur in nature. Polygenic inheritance and the longevity of a cultivar is also discussed briefly in relation to complex parasitic associations. Induced mutations can play a significant role in the study of complex parasitic associations, and thus can be very useful in controlling plant diseases

  19. The maintenance of hybrids by parasitism in a freshwater snail.

    Science.gov (United States)

    Guttel, Yonathan; Ben-Ami, Frida

    2014-11-01

    Hybrids have often been labelled evolutionary dead-ends due to their lower fertility and viability. However, there is growing awareness that hybridisation between different species may play a constructive role in animal evolution as a means to create variability. Thus, hybridisation and introgression may contribute to adaptive evolution, for example with regards to natural antagonists (parasites, predators, competitors) and adaptation to local environmental conditions. Here we investigated whether parasite intensity contributes to the continuous recreation of hybrids in 74 natural populations of Melanopsis, a complex of freshwater snails with three species. We also examined, under laboratory conditions, whether hybrids and their parental taxa differ in their tolerance of low and high temperatures and salinity levels. Infections were consistently less prevalent in males than in females, and lower in snails from deeper habitats. Infection prevalence in hybrids was significantly lower than in the parental taxa. Low hybrid infection rates could not be explained by sediment type, snail density or geographic distribution of the sampling sites. Interestingly, infected hybrid snails did not show signs of parasite-induced gigantism, whereas all parental taxa did. We found that hybrids mostly coped with extreme temperatures and salinity levels as well as their parental taxa did. Taken together, our results suggest that Melanopsis hybrids perform better in the presence of parasites and environmental stress. This may explain the widespread and long-term occurrence of Melanopsis hybrids as evidenced by paleontological and biogeographic data. Hybridisation may be an adaptive host strategy, reducing infection rates and resisting gigantism. Copyright © 2014 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

  20. Zoonotic enteric parasites transmitted from dogs in Egypt with special concern to Toxocara canis infection

    Directory of Open Access Journals (Sweden)

    Maysa A. I. Awadallah

    2015-08-01

    Full Text Available Aim: This work aimed to study the role played by dogs in transmitting zoonotic enteric parasites to humans in Egypt and to analyze the risk factors associated with the occurrence of such infection in dogs. Serodiagnosis of anti-Toxocara immunoglobulin G (IgG antibodies among human beings as well as analyzing risk factors predispose to Toxocara canis infection in human beings are another objectives of this study. Materials and Methods: From June to December 2013, a total of 130 fecal samples from 4 dog populations (Military, nomadic and domiciled dogs from rural and high standard districts and 150 stool samples of 6 occupational groups were examined for the presence of enteric parasitic infection. Moreover, 150 serum samples were collected from humans from whom stool samples were collected and examined for the presence of anti-T. canis antibodies. Results: Enteric parasites were detected in 30% of fecal samples from 4 dog populations in Egypt. High infectivity had been reported in nomadic dogs (63.33% (Crude odds ratios [COR]=67.36, 95% confidence interval [CI]=8.09-560.8, p˂0.000, followed by domiciled dogs from rural areas (40% (COR=26, 95% CI=3.14-215.54, p=0.003, domiciled dogs from high standard areas (23.33% (COR=11.87, 95% CI=1.37-102.69, p=0.025 and military dogs (2.5%. Twelve species of enteric parasites were identified, Ancylostomatidae (6.15%, T. canis and Cryptosporidium spp. (5.38%, each, Heterophyes spp. (3.85%, Toxocara leonina and Blastocystis spp. (3.07%, Taenidae eggs (2.31%, Hymenolepis diminuta (1.54% and Entamoeba canis, Cyclospora cayetanensis, and Paragonimus spp. (0.77%, each. Univariate logestic regression revealed significant association of age (COR=4.73, 95% CI=2.13-10.53, p˂0.000, gender (COR=2.63, 95% CI=1.22-5.68, p˂0.014, housing system (COR=5.10, 95% CI=2.04-12.75, p˂0.000 with enteric parasitic infection in dogs. However, breeds (COR=6.91, 95% CI=0.88-54.52, p=0.067 and type of feeding (COR ranged from 3.5 to

  1. Egg size matching by an intraspecific brood parasite

    Science.gov (United States)

    Lemons, Patrick R.; Sedinger, James S.

    2011-01-01

    Avian brood parasitism provides an ideal system with which to understand animal recognition and its affect on fitness. This phenomenon of laying eggs in the nests of other individuals has classically been framed from the perspective of interspecific brood parasitism and host recognition of parasitic eggs. Few examples exist of strategies adopted by intraspecific brood parasites to maximize success of parasitic eggs. Intraspecific brood parasitism within precocial birds can be a risky strategy in that hatch synchrony is essential to reproductive success. Given that egg size is positively correlated with incubation time, parasitic birds would benefit by recognizing and selecting hosts with a similar egg size. Intraspecific brood parasitism is an alternative reproductive strategy in black brant (Branta bernicla nigricans), a colonial nesting goose with precocial young. Based on a randomization test, parasitic eggs in this study differed less in size from eggs in their host's nests than did random eggs placed in random nests. Parasitic eggs were remarkably similar in size to hosts’ eggs, differing by nests differed by nearly 8%. The precision with which parasitic brant match the egg size of hosts in our study supports our hypothesis that brant match egg size of hosts, thereby maximizing hatching success of their parasitic eggs.

  2. Cellulose filtration of blood from malaria patients for improving ex vivo growth of Plasmodium falciparum parasites

    DEFF Research Database (Denmark)

    Mkumbaye, Sixbert I; Minja, Daniel T R; Jespersen, Jakob S

    2017-01-01

    faster than non-filtered parasites seemingly due to a higher development ratio of ring stage parasites progressing into the late stages. Cellulose filtration had no apparent effect on clonality or var gene expression; however, evident differences were observed after only 4 days of culture in both...

  3. Dynamics of anti-MSP3 and Pfs230 antibody responses and multiplicity of infection in asymptomatic children from southern Ghana

    DEFF Research Database (Denmark)

    Amoah, Linda E; Acquah, Festus K; Ayanful-Torgby, Ruth

    2018-01-01

    BACKGROUND: During a Plasmodium infection, exposure of human host immune cells to both the asexual and the sexual stages of the parasite elicit immune responses. These responses may be protective and prevent the development of high parasitaemia and its associated clinical symptoms, or block...... the transmission of malaria to an uninfected person. This study aimed at examining the dynamics of naturally acquired immune responses against the asexual and sexual forms of Plasmodium falciparum as well as assessing differences in the multiplicity of infection (MOI) in asymptomatic Ghanaian children living...... 2015. Filter paper blood blots (DBS) as well as thick and thin blood smears were made from finger-pricked blood at each visit. Plasmodium falciparum parasite prevalence was determined by microscopy and PCR. Serum eluted from the DBS were used to assess anti-Pfs230 (sexual stage) and anti-MSP3 (asexual...

  4. In vitro evaluation of the anti-leishmanial activity and toxicity of PK11195

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Sampaio Guedes

    2018-02-01

    Full Text Available BACKGROUND Leishmaniasis, one of the most neglected diseases, is a serious public health problem in many countries, including Brazil. Currently available treatments require long-term use and have serious side effects, necessitating the development of new therapeutic interventions. Because translocator protein (TSPO levels are reduced in Leishmania amazonensis-infected cells and because this protein participates in apoptosis and immunomodulation, TSPO represents a potential target for Leishmania chemotherapy. The present study evaluated PK11195, a ligand of this protein, as an anti-leishmanial agent. OBJECTIVE To evaluate the leishmanicidal activity of PK11195 against L. amazonensis in infected CBA mouse macrophages in vitro. METHODS The viability of axenic L. amazonensis, Leishmania major, and Leishmania braziliensis promastigotes was assessed after 48 h treatment with PK11195 (0.2-400 µM. Additionally, intracellular parasite viability was evaluated to determine IC50 values and the number of viable parasites in infected macrophages treated with PK11195 (50-100 µM. Infected macrophages were then treated with PK11195 (25-100 µM to determine the percentage of L. amazonensis-infected cells and the number of parasites per infected cell. Electron microscopy was used to investigate morphological changes caused by PK11195. The production of free oxygen radicals, nitric oxide, and pro-inflammatory cytokines was also evaluated in infected macrophages treated with PK11195 and primed or not primed with IFN-γ. FINDINGS Median IC50 values for PK11195 were 14.2 µM for L. amazonensis, 8.2 µM for L. major, and 3.5 µM for L. braziliensis. The selective index value for L. amazonensis was 13.7, indicating the safety of PK11195 for future testing in mammals. Time- and dose-dependent reductions in the percentage of infected macrophages, the number of parasites per infected macrophage, and the number of viable intracellular parasites were observed. Electron

  5. Subversion of complement by hematophagous parasites.

    Science.gov (United States)

    Schroeder, Hélène; Skelly, Patrick J; Zipfel, Peter F; Losson, Bertrand; Vanderplasschen, Alain

    2009-01-01

    The complement system is a crucial part of innate and adaptive immunity which exerts a significant evolutionary pressure on pathogens. It has selected for those pathogens, mainly microorganisms but also parasites, that have evolved countermeasures. The characterization of how pathogens evade complement attack is a rapidly developing field of current research. In recent years, multiple complement evasion strategies have been characterized. In this review, we focus on complement escape mechanisms expressed by hematophagous parasites, a heterogeneous group of metazoan parasites that share the property of ingesting the whole blood of their host. Complement inhibition is crucial for parasite survival within the host tissue or to facilitate blood feeding. Finally, complement inhibition by hematophagous parasites may also contribute to their success as pathogen vectors.

  6. Activity of medicinal plants from Ghana against the parasitic gut protist Blastocystis.

    Science.gov (United States)

    Bremer Christensen, Charlotte; Soelberg, Jens; Stensvold, Christen R; Jäger, Anna K

    2015-11-04

    The plants tested in this study were examples of plants historically used to treat or alleviate several types of stomach disorders manifested by e.g. stomachache, diarrhoea or dysentery. These plants have been consumed typically as a decoction, sometimes mixed with other flavourings. The aim of this study was to evaluate the anti-Blastocystis activity of 24 plant parts from 21 medicinal plants from Ghana. The medicinal plants were collected in the Greater Accra region of Ghana. Every plant part was tested in three different extracts; an ethanolic, a warm, and a cold water extract, at a final concentration of 1 mg/mL for the initial screening, and in a range from 0.0156 to 1mg/mL for determination of inhibitory concentrations. The obligate anaerobic parasitic gut protist Blastocystis (subtype 4) was used as a 48 h old subcultivated isolate in the final concentration of 10(6) cells/mL. Plant extracts inoculated with Blastocystis were incubated at 37 °C for 24 h and 48 h. Both MIC minimum inhibitory concentration (MIC90) assays and minimal lethal concentration (MLC) assays were performed after 24 h and 48 h. The half maximal inhibitory concentration (IC50) was derived after 24 h and 48 h. Antimicrobial activity was tested against two Gram-positive and two Gram-negative bacteria for all 24 plant parts at a final concentration of 1mg/mL. Screening of the 24 different plant parts showed significant anti-Blastocystis activity of six of the ethanolic extracts: Mallotus oppositifolius, IC50, 24 h 27.8 µg/mL; Vemonia colorata, IC50, 24 h 117.9 µg/mL; Zanthoxylum zanthoxyloides, cortex IC50, 24 h 255.6 µg/mL; Clausena anisata, IC50, 24 h 314.0 µg/mL; Z. zanthoxyloides, radix IC50, 24 h 335.7 µg/mL and Eythrina senegalensis, IC50, 24 h 527.6 µg/mL. The reference anti-protozoal agent metronidazole (MTZ) had an IC50, 24 h of 7.6 µg/mL. Only C. anisata showed antimicrobial activity at a concentration of 800 µg/mL. Six ethanolic plant extracts showed significant anti-parasitic

  7. The effect of malaria and anti-malarial drugs on skeletal and cardiac muscles.

    Science.gov (United States)

    Marrelli, Mauro Toledo; Brotto, Marco

    2016-11-02

    Malaria remains one of the most important infectious diseases in the world, being a significant public health problem associated with poverty and it is one of the main obstacles to the economy of an endemic country. Among the several complications, the effects of malaria seem to target the skeletal muscle system, leading to symptoms, such as muscle aches, muscle contractures, muscle fatigue, muscle pain, and muscle weakness. Malaria cause also parasitic coronary artery occlusion. This article reviews the current knowledge regarding the effect of malaria disease and the anti-malarial drugs on skeletal and cardiac muscles. Research articles and case report publications that addressed aspects that are important for understanding the involvement of malaria parasites and anti-malarial therapies affecting skeletal and cardiac muscles were analysed and their findings summarized. Sequestration of red blood cells, increased levels of serum creatine kinase and reduced muscle content of essential contractile proteins are some of the potential biomarkers of the damage levels of skeletal and cardiac muscles. These biomarkers might be useful for prevention of complications and determining the effectiveness of interventions designed to protect cardiac and skeletal muscles from malaria-induced damage.

  8. Mechanisms of host seeking by parasitic nematodes.

    Science.gov (United States)

    Gang, Spencer S; Hallem, Elissa A

    2016-07-01

    The phylum Nematoda comprises a diverse group of roundworms that includes parasites of vertebrates, invertebrates, and plants. Human-parasitic nematodes infect more than one billion people worldwide and cause some of the most common neglected tropical diseases, particularly in low-resource countries [1]. Parasitic nematodes of livestock and crops result in billions of dollars in losses each year [1]. Many nematode infections are treatable with low-cost anthelmintic drugs, but repeated infections are common in endemic areas and drug resistance is a growing concern with increasing therapeutic and agricultural administration [1]. Many parasitic nematodes have an environmental infective larval stage that engages in host seeking, a process whereby the infective larvae use sensory cues to search for hosts. Host seeking is a complex behavior that involves multiple sensory modalities, including olfaction, gustation, thermosensation, and humidity sensation. As the initial step of the parasite-host interaction, host seeking could be a powerful target for preventative intervention. However, host-seeking behavior remains poorly understood. Here we review what is currently known about the host-seeking behaviors of different parasitic nematodes, including insect-parasitic nematodes, mammalian-parasitic nematodes, and plant-parasitic nematodes. We also discuss the neural bases of these behaviors. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. De novo assembly and characterization of the transcriptome of the parasitic weed dodder identifies genes associated with plant parasitism.

    Science.gov (United States)

    Ranjan, Aashish; Ichihashi, Yasunori; Farhi, Moran; Zumstein, Kristina; Townsley, Brad; David-Schwartz, Rakefet; Sinha, Neelima R

    2014-11-01

    Parasitic flowering plants are one of the most destructive agricultural pests and have major impact on crop yields throughout the world. Being dependent on finding a host plant for growth, parasitic plants penetrate their host using specialized organs called haustoria. Haustoria establish vascular connections with the host, which enable the parasite to steal nutrients and water. The underlying molecular and developmental basis of parasitism by plants is largely unknown. In order to investigate the process of parasitism, RNAs from different stages (i.e. seed, seedling, vegetative strand, prehaustoria, haustoria, and flower) were used to de novo assemble and annotate the transcriptome of the obligate plant stem parasite dodder (Cuscuta pentagona). The assembled transcriptome was used to dissect transcriptional dynamics during dodder development and parasitism and identified key gene categories involved in the process of plant parasitism. Host plant infection is accompanied by increased expression of parasite genes underlying transport and transporter categories, response to stress and stimuli, as well as genes encoding enzymes involved in cell wall modifications. By contrast, expression of photosynthetic genes is decreased in the dodder infective stages compared with normal stem. In addition, genes relating to biosynthesis, transport, and response of phytohormones, such as auxin, gibberellins, and strigolactone, were differentially expressed in the dodder infective stages compared with stems and seedlings. This analysis sheds light on the transcriptional changes that accompany plant parasitism and will aid in identifying potential gene targets for use in controlling the infestation of crops by parasitic weeds. © 2014 American Society of Plant Biologists. All Rights Reserved.

  10. Integrated parasite management

    DEFF Research Database (Denmark)

    Clausen, Jesper Hedegaard; Madsen, Henry; Van, Phan Thi

    2015-01-01

    communities at risk through mass drug administration. However, we argue that treatment alone will not reduce the risk from eating infected fish and that sustainable effective control must adopt an integrated FZT control approach based on education, infrastructure improvements, and management practices...... that target critical control points in the aquaculture production cycle identified from a thorough understanding of FZT and host biology and epidemiology. We present recommendations for an integrated parasite management (IPM) program for aquaculture farms.......Fishborne zoonotic trematodes (FZT) are an emerging problem and there is now a consensus that, in addition to wild-caught fish, fish produced in aquaculture present a major food safety risk, especially in Southeast Asia where aquaculture is important economically. Current control programs target...

  11. The adaptive significance of inquiline parasite workers

    DEFF Research Database (Denmark)

    Sumner, Seirian; Nash, David R; Boomsma, Jacobus J

    2003-01-01

    Social parasites exploit the socially managed resources of their host's society. Inquiline social parasites are dependent on their host throughout their life cycle, and so many of the traits inherited from their free-living ancestor are removed by natural selection. One trait that is commonly lost...... is the worker caste, the functions of which are adequately fulfilled by host workers. The few inquiline parasites that have retained a worker caste are thought to be at a transitional stage in the evolution of social parasitism, and their worker castes are considered vestigial and non-adaptive. However...... a vital role in ensuring the parasite's fitness. We show that the presence of these parasite workers has a positive effect on the production of parasite sexuals and a negative effect on the production of host sexuals. This suggests that inquiline workers play a vital role in suppressing host queen...

  12. Rare species of fungi parasiting on algae I. Parasites of Spirogyra and Mougeotia

    Directory of Open Access Journals (Sweden)

    Joanna Z. Kadłubowska

    2014-08-01

    Full Text Available Investigations carried out on the genus Spirogyra Link and Mougeotia Agardh revealed the following species of fungi parasiting in the Spirogyra and Mougeotia cells: Olpidium endogenum, Blyttiomyces helicus, B. spinulosus, Micromyces zygogonii and Rhizophydium ampullaceum. First information on B. helicus as parasitic on algae is presented.

  13. Self-medication as adaptive plasticity: increased ingestion of plant toxins by parasitized caterpillars.

    Directory of Open Access Journals (Sweden)

    Michael S Singer

    Full Text Available Self-medication is a specific therapeutic behavioral change in response to disease or parasitism. The empirical literature on self-medication has so far focused entirely on identifying cases of self-medication in which particular behaviors are linked to therapeutic outcomes. In this study, we frame self-medication in the broader realm of adaptive plasticity, which provides several testable predictions for verifying self-medication and advancing its conceptual significance. First, self-medication behavior should improve the fitness of animals infected by parasites or pathogens. Second, self-medication behavior in the absence of infection should decrease fitness. Third, infection should induce self-medication behavior. The few rigorous studies of self-medication in non-human animals have not used this theoretical framework and thus have not tested fitness costs of self-medication in the absence of disease or parasitism. Here we use manipulative experiments to test these predictions with the foraging behavior of woolly bear caterpillars (Grammia incorrupta; Lepidoptera: Arctiidae in response to their lethal endoparasites (tachinid flies. Our experiments show that the ingestion of plant toxins called pyrrolizidine alkaloids improves the survival of parasitized caterpillars by conferring resistance against tachinid flies. Consistent with theoretical prediction, excessive ingestion of these toxins reduces the survival of unparasitized caterpillars. Parasitized caterpillars are more likely than unparasitized caterpillars to specifically ingest large amounts of pyrrolizidine alkaloids. This case challenges the conventional view that self-medication behavior is restricted to animals with advanced cognitive abilities, such as primates, and empowers the science of self-medication by placing it in the domain of adaptive plasticity theory.

  14. Non-Genetic Determinants of Mosquito Competence for Malaria Parasites

    Science.gov (United States)

    Lefèvre, Thierry; Vantaux, Amélie; Dabiré, Kounbobr R.; Mouline, Karine; Cohuet, Anna

    2013-01-01

    Understanding how mosquito vectors and malaria parasites interact is of fundamental interest, and it also offers novel perspectives for disease control. Both the genetic and environmental contexts are known to affect the ability of mosquitoes to support malaria development and transmission, i.e., vector competence. Although the role of environment has long been recognized, much work has focused on host and parasite genetic effects. However, the last few years have seen a surge of studies revealing a great diversity of ways in which non-genetic factors can interfere with mosquito-Plasmodium interactions. Here, we review the current evidence for such environmentally mediated effects, including ambient temperature, mosquito diet, microbial gut flora, and infection history, and we identify additional factors previously overlooked in mosquito-Plasmodium interactions. We also discuss epidemiological implications, and the evolutionary consequences for vector immunity and parasite transmission strategies. Finally, we propose directions for further research and argue that an improved knowledge of non-genetic influences on mosquito-Plasmodium interactions could aid in implementing conventional malaria control measures and contribute to the design of novel strategies. PMID:23818841

  15. Non-genetic determinants of mosquito competence for malaria parasites.

    Directory of Open Access Journals (Sweden)

    Thierry Lefèvre

    Full Text Available Understanding how mosquito vectors and malaria parasites interact is of fundamental interest, and it also offers novel perspectives for disease control. Both the genetic and environmental contexts are known to affect the ability of mosquitoes to support malaria development and transmission, i.e., vector competence. Although the role of environment has long been recognized, much work has focused on host and parasite genetic effects. However, the last few years have seen a surge of studies revealing a great diversity of ways in which non-genetic factors can interfere with mosquito-Plasmodium interactions. Here, we review the current evidence for such environmentally mediated effects, including ambient temperature, mosquito diet, microbial gut flora, and infection history, and we identify additional factors previously overlooked in mosquito-Plasmodium interactions. We also discuss epidemiological implications, and the evolutionary consequences for vector immunity and parasite transmission strategies. Finally, we propose directions for further research and argue that an improved knowledge of non-genetic influences on mosquito-Plasmodium interactions could aid in implementing conventional malaria control measures and contribute to the design of novel strategies.

  16. A selective study of Information technologies to improve operations efficiency in construction

    Directory of Open Access Journals (Sweden)

    Konikov Alexandr

    2018-01-01

    Full Text Available Today, information technologies (IT are used in almost every production industry. While the aspects of IT are well studied and discussed in relevant monographs, articles, web sources, etc., this paper reviews the performance improvement options in the construction industry by leveraging IT. From a wide range of information technologies the author has picked the most relevant solutions, from his point of view, based on several considerations, the most important one being the lack of adequate attention to these technologies specifically in the construction industry. The paper covers the following technologies: Big Data (a smart technology for high-speed processing of huge and diverse data arrays; situation centers (SC for construction and operations projects (SCs are successfully used in other industries for operating control of sophisticated facilities; data warehouses (DW for the construction industry (DWs are viewed as a standalone project rather than a supplement to Data Mining or Big Data; operational and dispatch radio communication service (radio communication can ensure instant connectivity between several subscribers; VSAT (a satellite technology for prompt connection of a distant construction site with the 'outer world' when no alternatives are available. The paper briefly presents the essence of each technology, describes the pre-requisites for its use in construction, outlines the key advantages, limits and shortcomings, and lists construction projects where it shall be worthwhile to use a specific technology projects.

  17. The Fermilab anti pp collider

    International Nuclear Information System (INIS)

    Harrison, M.

    1984-01-01

    The goal of the Tevatron I project is to achieve anti pp collisions in the centre-of-mass energy range up to 2 TeV with a luminosity of at least 10 30 cm -2 sec -1 . The project involves adapting the Tevatron to function as a storage ring and modifying the lattice to provide low-beta interaction points; changes to the Main Ring to allow anti p transfers and the installation of experimental equipment; and the construction of a anti p source. Major experimental areas will be located in the socalled BO and DO straight sections together with smaller, more specialized experiments in several of the other interacting regions. (orig./HSI)

  18. Improving Asphalt Mixtures Performance by Mitigating Oxidation Using Anti-Oxidants Additives

    Science.gov (United States)

    Dessouky, Samer; Diaz, Manuel

    Polymer modified additives are typically used to improve rheological properties of asphalt binder as well as mechanical properties of asphalt concrete mix. In this study, polymer-modified binder PG70-22 is mixing with two co-polymers enhanced with anti-oxidant agents namely; Solution Styrene-Butadiene Rubber (SSBR) and Solution Ethylene-Butylene/Styrene (SEBS). The objective of this study is to characterize the effect of those additives into the rheological properties of the asphalt binder using temperature sweep test and mechanical properties of asphalt mixes. The aging index is determined to evaluate the role of additives to reduce brittleness after aging of the binder. The performance of asphalt mixes were characterized by Hamburg Wheel Tracking Test for moisture damage, Beam Fatigue Test for fatigue properties and Flow Number Test for rutting performance. It is found that the asphalt mixes with enhanced binders are improving its rutting and moisture resistance but decreased its fatigue life compared to the control mix.

  19. Intestinal parasitic infection among school children.

    Science.gov (United States)

    Shakya, B; Shrestha, S; Madhikarmi, N L; Adhikari, R

    2012-01-01

    Intestinal parasitosis is a major public health problem of developing countries, children being major victims. Higher prevalence has been reported among school children, mostly in hilly regions of Nepal. This study aims at assessing prevalence of intestinal parasitosis among school children of a school in a border town of Nepal and the associated factors. Fecal samples from the students were examined by direct smear technique and result was correlated with their socioeconomic status and hygienic behavior. The chi-square test was used for analytical assessment. The prevalence rate was 13.9%, girls being highly infected (19.1%) than boys (10.3%) (P>0.05). Entamoeba histolytica (36.0%) was the commonest parasite followed by A. lumbricoides (28.0%). The highest positive rate was found among children of 5 years and less age (29.2%) and least among those above 12 years (5.3%) (P>0.05). Those from family size 5 and less than 5 were least infected (10.5%). Children of illiterate parents (16.7%) and farmers (17.1%) were more infected than literate ones and non-farmers (P>0.05). 8.7% of positive children had multi-parasitic infection. Children drinking untreated water (15.0%) were more infected than those drinking treated water (5.5%) (P>0.05). Intestinal parasitic infection was found among 17% school children. Awareness on infectious diseases, improving hygiene, and application of supportive programs for parents to elevate socioeconomic conditions may reduce the burden of infection.

  20. Glyoxalase diversity in parasitic protists.

    Science.gov (United States)

    Deponte, Marcel

    2014-04-01

    Our current knowledge of the isomerase glyoxalase I and the thioesterase glyoxalase II is based on a variety of prokaryotic and eukaryotic (model) systems with an emphasis on human glyoxalases. During the last decade, important insights on glyoxalase catalysis and structure-function relationships have also been obtained from parasitic protists. These organisms, including kinetoplastid and apicomplexan parasites, are particularly interesting, both because of their relevance as pathogens and because of their phylogenetic diversity and host-parasite co-evolution which has led to specialized organellar and metabolic adaptations. Accordingly, the glyoxalase repertoire and properties vary significantly among parasitic protists of different major eukaryotic lineages (and even between closely related organisms). For example, several protists have an insular or non-canonical glyoxalase. Furthermore, the structures and the substrate specificities of glyoxalases display drastic variations. The aim of the present review is to highlight such differences as well as similarities between the glyoxalases of parasitic protists and to emphasize the power of comparative studies for gaining insights into fundamental principles and alternative glyoxalase functions.

  1. Method of constructing an improved electrochemical cell

    Science.gov (United States)

    Grimes, Patrick G.; Einstein, Harry

    1984-10-09

    An electrochemical cell construction features a novel co-extruded plastic electrode in an interleaved construction with a novel integral separator-spacer. Also featured is a leak and impact resistant construction for preventing the spill of corrosive materials in the event of rupture.

  2. [Anti-Trypanosoma cruzi antibodies in Latin American migrants in transit through the México- USA border].

    Science.gov (United States)

    Montes-Rincón, Laura Mayela; Galaviz-Silva, Lucio; Molina-Garza, Zinnia Judith

    2018-03-15

    In recent years, American trypanosomiasis has become an emergent public health problem in countries receiving migrant populations such as México, USA, Canada or those in Europe. To analyze the prevalence of anti-Trypanosoma cruzi antibodies in Latin American migrants on their way to USA and Canada by means of serological techniques. ELISA and IHA were performed to detect anti-T. cruzi antibodies. Also, each participant filled out a socioeconomic questionnaire to determine the associated factors with seropositive cases, which could facilitate the transmission in the migrants' country of origin. Total seroprevalence among the studied population was 20% (24/120). The highest prevalence was found in migrants from Guatemala with 37.5% (6/16), followed by Honduras (22.6%; 12/53), El Salvador (16%; 4/25), and México (8.7%, 3/23). From the total 120 surveyed migrants, 105 (87.5%) recognized the vector of Chagas' disease, and 62 (59%) assured having been bitten by it. Highly significant statistical associations were found between infection and the construction materials for walls and the presence of pets (dogs) inside houses (p≤0.01), as well as with the building materials for backyards, inadequate basic services, and animal breeding inside corrals built around dwellings (p≤0.05). Non-endemic countries receiving migrants from endemic areas should enhance or develop better health policies to prevent transfusion-transmitted Chagas or congenital parasite transmission.

  3. Intestinal parasite infection in children from primary school in Florianopolis (SC – environmental and health education

    Directory of Open Access Journals (Sweden)

    José Roberto S. A. Leite

    2008-12-01

    Full Text Available Parasite infection remains an important public health problem in many areas around the world as well as in Brazil, and it is frequently associated with poverty and lack of sanitation facilities. A coprological investigation was conducted in children from the primary school Intendente Aricomedes da Silva in Florianopolis, Brazil, in order to determine the prevalence of intestinal parasite infections. Also a series of indoor and outdoor activities were carried out to improve the awareness of students, parents, and school staff about parasite infection. Fecal samples from 101 school children and 5 school adult staff were collected and analyzed from June to December 2006. Thirty-eight individuals (35.8% were positive for at least one parasite. Ascaris lumbricoides, the most frequent helminth, was prevalent in 5.7% of individuals. Entamoeba coli and Endolimax nana were the most prevalent protozoa in this study: 20.7% and 12.3% respectively. Although non pathogenic protozoa species, they indicate oral-fecal contamination. Infected individuals were sent to the Health Unit for treatment. Finally, a meeting with the school community was organized to discuss how to prevent intestinal parasite infections by improving basic hygiene habits and best practice with water, food and environment.

  4. Brood parasitism and quasi-parasitism in the European barn swallow Hirundo rustica rustica

    Czech Academy of Sciences Publication Activity Database

    Petrželková, Adéla; Michálková, R.; Albrechtová, Jana; Cepák, J.; Honza, Marcel; Kreisinger, J.; Munclinger, P.; Soudková, M.; Tomášek, Oldřich; Albrecht, Tomáš

    2015-01-01

    Roč. 69, č. 9 (2015), s. 1405-1414 ISSN 0340-5443 R&D Projects: GA ČR(CZ) GAP506/12/2472 Institutional support: RVO:68081766 Keywords : Altricial birds * Colonial breeding * Conspecific brood parasitism * Egg dumping * Host fitness * Parasite fitness Subject RIV: EG - Zoology Impact factor: 2.382, year: 2015

  5. Nematode parasites of animals are more prone to develop xenobiotic resistance than nematode parasites of plants

    Directory of Open Access Journals (Sweden)

    Silvestre A.

    2004-06-01

    Full Text Available In this paper, we concentrate on a comparison of plant and animal-parasitic nematodes, to gain insight into the factors that influence the acquisition of the drug resistance by nematodes. Comparing nematode parasite of domestic animals and cultivated plants, it appears that drug resistance threatens only domestic animal production. Does the paucity of report on nematicide field resistance reflect reality or, is nematicide resistance bypassed by other management practices, specific to cultivated plants (i.e. agricultural control ? First, it seems that selection pressure by treatments in plants is not as efficient as selection pressure in ruminants. Agronomic practices (i.e. sanitation, early planting, usage of nematodes resistant cultivar and crop rotation are frequently used to control parasitic-plant nematodes. Although the efficiency of such measures is generally moderate to high, integrated approaches are developing successfully in parasitic-plant nematode models. Secondly, the majority of anthelmintic resistance cases recorded in animal-parasitic nematodes concern drug families that are not used in plant-parasitic nematodes control (i.e. benzimidazoles, avermectines and levamisole. Thirdly, particular life traits of parasitic-plant nematodes (low to moderate fecundity and reproductive strategy are expected to reduce probability of appearance and transmission of drug resistance genes. It has been demonstrated that, for a large number of nematodes such as Meloidogyne spp., the mode of reproduction by mitotic parthenogenesis reduced genetic diversity of populations which may prevent a rapid drug resistance development. In conclusion, anthelmintic resistance develops in nematode parasite of animals as a consequence of an efficient selection pressure. Early detection of anthelmintic resistance is then crucial : it is not possible to avoid it, but only to delay its development in farm animal industry.

  6. The Eimeria Transcript DB: an integrated resource for annotated transcripts of protozoan parasites of the genus Eimeria

    Science.gov (United States)

    Rangel, Luiz Thibério; Novaes, Jeniffer; Durham, Alan M.; Madeira, Alda Maria B. N.; Gruber, Arthur

    2013-01-01

    Parasites of the genus Eimeria infect a wide range of vertebrate hosts, including chickens. We have recently reported a comparative analysis of the transcriptomes of Eimeria acervulina, Eimeria maxima and Eimeria tenella, integrating ORESTES data produced by our group and publicly available Expressed Sequence Tags (ESTs). All cDNA reads have been assembled, and the reconstructed transcripts have been submitted to a comprehensive functional annotation pipeline. Additional studies included orthology assignment across apicomplexan parasites and clustering analyses of gene expression profiles among different developmental stages of the parasites. To make all this body of information publicly available, we constructed the Eimeria Transcript Database (EimeriaTDB), a web repository that provides access to sequence data, annotation and comparative analyses. Here, we describe the web interface, available sequence data sets and query tools implemented on the site. The main goal of this work is to offer a public repository of sequence and functional annotation data of reconstructed transcripts of parasites of the genus Eimeria. We believe that EimeriaTDB will represent a valuable and complementary resource for the Eimeria scientific community and for those researchers interested in comparative genomics of apicomplexan parasites. Database URL: http://www.coccidia.icb.usp.br/eimeriatdb/ PMID:23411718

  7. From Parasite Encounter to Infection: Multiple-Scale Drivers of Parasite Richness in a Wild Social Primate Population

    Science.gov (United States)

    Benavides J. A.; Huchard, E.; Pettorelli, N.; King, A. J.; Brown, M. E.; Archer, C. E.; Appleton, C. C.; Raymond, M.; Cowlishaw, G.

    2011-01-01

    Host parasite diversity plays a fundamental role in ecological and evolutionary processes, yet the factors that drive it are still poorly understood. A variety of processes, operating across a range of spatial scales, are likely to influence both the probability of parasite encounter and subsequent infection. Here, we explored eight possible determinants of parasite richness, comprising rainfall and temperature at the population level, ranging behavior and home range productivity at the group level, and age, sex, body condition, and social rank at the individual level. We used a unique dataset describing gastrointestinal parasites in a terrestrial subtropical vertebrate (chacma baboons, Papio ursinus), comprising 662 faecal samples from 86 individuals representing all age-sex classes across two groups over two dry seasons in a desert population. Three mixed models were used to identify the most important factor at each of the three spatial scales (population, group, individual); these were then standardised and combined in a single, global, mixed model. Individual age had the strongest influence on parasite richness, in a convex relationship. Parasite richness was also higher in females and animals in poor condition, albeit at a lower order of magnitude than age. Finally, with a further halving of effect size, parasite richness was positively correlated to day range and temperature. These findings indicate that a range of factors influence host parasite richness through both encounter and infection probabilities, but that individual-level processes may be more important than those at the group or population level.

  8. Parasites of mammals species abundance near zone Chernobyl

    International Nuclear Information System (INIS)

    Pen'kevich, V.A.

    2014-01-01

    In wildlife reserve parasitize various types of parasites: arachnids (mites) parasitic insects (horseflies, keds, mosquitoes, gnats, midges), helminths (trematodes, cestodes, nematodes and acanthocephalans) and parasitic protozoa. In quantity: 3 (beaver) to 25 species (wolf). (authors)

  9. Doenças parasitárias em ruminantes no semi-árido brasileiro Parasitic diseases in ruminants in the Brazilian semiarid

    Directory of Open Access Journals (Sweden)

    Valéria Medeiros de M. Costa

    2009-07-01

    Full Text Available Arquivos de fichas clínicas de ruminantes ou amostras para diagnósticos recebidos pelo Hospital Veterinário da Universidade de Campina Grande, em Patos, Paraíba, de janeiro 2000 a agosto 2007, foram revisados para avaliar alguns aspectos epidemiológicos de doenças parasitárias de ruminantes na região semi-árida da Paraíba e estados vizinhos. A região apresenta precipitações médias anuais de aproximadamente 800mm, com chuvas irregulares concentradas em um período de 3-4 meses e uma temperatura média anual de 26°C. No período, 163 (5,31% de 3.064 ruminantes foram afetados por alguma doença parasitária clinica. A doença parasitária mais frequente em caprinos e ovinos foi a helmitose gastrointestinal, principalmente a hemonchose, e caprinos foram mais afetados (6,24% dos casos diagnosticados do que os ovinos (4,7% dos casos diagnosticados. A maior freqüência da doença nos caprinos pode estar associada à maior susceptibilidade destes ou devido a erros no tratamento, como a utilização da mesma dose para as duas espécies, o que para a maioria dos anti-antihelmínticos é insuficiente para caprinos. Bovinos tiveram uma baixa freqüência de helmintoses gastrintestinais (1 de 1.113 casos. Esta baixa freqüência deveu-se, provavelmente, ao sistema de criação no semi-árido, com baixa taxa de lotação, até um animal adulto por hectare a cada 13-16 hectare, e a permanência de bezerros (suscetíveis com as mães (resistentes por períodos de até um ano antes da desmama. A ocorrência de eimeriose em caprinos e ovinos foi de 0,76% dos casos, envolvendo apenas os animais jovens. Em bovinos a principal doença foi à tristeza parasitária com 14 surtos. Os surtos de tristeza ocorreram principalmente no final do período chuvoso em áreas de desequilíbrio enzoótico incluindo as montanhas e planaltos da região da Borborema, áreas irrigadas, e áreas das bacias do Rio do Peixe e Rio Piranhas. Nas áreas mais secas do semi

  10. Parasites in Forensic Science: a historic perspective

    Science.gov (United States)

    Cardoso, Rita; Alves, Helena; Richter, Joachim; Botelho, Monica C

    Parasites show a great potential to Forensic Science. Forensic Science is the application of any science and methodology to the legal system. The forensic scientist collects and analyses the physical evidence and produce a report of the results to the court. A parasite is an organism that lives at the expense of another and they exist in any ecosystem. Parasites are the cause of many important diseases. The forensic scientists can use the parasites to identify a crime scene, to determine the murder weapon or simply identify an individual. The applications for parasites in the Forensic Science can be many and more studies should be made in Forensic Parasitology. The most important parasites in Forensic Science are helminths specifically schistosomes. Through history there are many cases where schistosomes were described in autopsies and it was related to the cause of death. Here we review the applications of parasites in Forensic Science and its importance to the forensic scientist.

  11. Early pathologic findings and long-term improvement in anti-Ma2-associated encephalitis.

    Science.gov (United States)

    Blumenthal, D T; Salzman, K L; Digre, K B; Jensen, R L; Dunson, W A; Dalmau, J

    2006-07-11

    A 67-year-old man sequentially developed anti-Ma2-associated paraneoplastic encephalitis (PNE) and contralateral herpes simplex encephalitis (HSE). Brain biopsy 1 month before HSE revealed extensive infiltrates of T cells, B cells, and plasma cells. Most T cells expressed the cytotoxic granule-associated protein TIA-1 and the membranolytic protein granzyme-B. Although recovery was thought to be unlikely, treatment of the PNE with corticosteroids and resection of the associated lung cancer resulted in dramatic improvement for 21 months.

  12. Meso- and bathy-pelagic fish parasites at the Mid-Atlantic Ridge (MAR): Low host specificity and restricted parasite diversity

    Science.gov (United States)

    Klimpel, Sven; Busch, Markus Wilhelm; Sutton, Tracey; Palm, Harry Wilhelm

    2010-04-01

    Seven meso- and bathy-pelagic fish species from the Mid-Atlantic Ridge (MAR) were firstly studied for fish parasites and feeding ecology. With a total of seven parasite species, the 247 meso- and bathy-pelagic deep-sea fish specimens belonging to the families Melamphaidae (3 spp.), Myctophidae (3 spp.) and Stomiidae (1 sp.) revealed low parasite diversity. The genetically identified nematodes Anisakis simplex (s.s.) and Anisakis pegreffii from the body cavity, liver and muscles of Myctophum punctatum were the most abundant parasites, reaching a prevalence of 91.4% and mean intensity of 3.1 (1-14). Anisakis sp. (unidentified) infected Chauliodus sloani and Poromitra crassiceps. Bothriocephalidean and tetraphyllidean cestode larvae infected Benthosema glaciale, the latter also occurring in C. sloani and Scopelogadus beanii, at low prevalences. Adult parasites at low infection rates included the digenean Lethadena sp. (2.9%), and the two copepod species Sarcotretes scopeli (5.7%) and Tautochondria dolichoura (5.3-11.4%). The myctophid Lampanyctus macdonaldi and the melamphaid Scopelogadus mizolepis mizolepis were free of parasites. Analyses of the stomach contents revealed crustaceans, especially copepods and euphausiids for the myctophids and also amphipods for the melamphaids as predominant prey items. While all stomachs showing distinct content comprising often unidentified 'tissue' (possibly gelatinous zooplankton), only C. sloani preyed upon fish. Though this feeding habit would enable transfer of a variety of crustacean-transmitted parasites into the fish, the parasite fauna in the meso- and bathy-pelagic fish was species poor. All observed parasites showed low host specificity, demonstrating no distinct pattern of host-parasite co-evolution. The MAR is no barrier for the parasite distribution in the North Atlantic meso- and bathy-pelagial.

  13. Efficacy of garlic based treatments against monogenean parasites infecting the guppy (Poecilia reticulata (Peters)).

    Science.gov (United States)

    Fridman, S; Sinai, T; Zilberg, D

    2014-06-16

    Monogenean infections of commercially farmed fishes are responsible for significant economic losses. Garlic (Allium sativum) is a well-known spice which also possesses anti-microbial and anti-parasitical properties. The current work aimed to test the efficacy of garlic-based treatments against infection with monogenean sp. in the guppy (Poecilia reticulata). Clipped sections of tail fins of guppies heavily infected with Gyrodactylus turnbulli were exposed to aqueous garlic extract (7.5 to 30 mL L(-1)) and visually observed under a dissecting microscope. Results revealed that exposure to garlic caused detachment of parasite and cessation of movement indicating death. A positive correlation was seen between garlic concentration and time to detachment and death of parasites, which, at the highest concentration of 30 mL L(-1), occurred at 4.1 and 8.6 min, respectively. Bathing in aqueous garlic extract (7.5 and 12.5 mL L(-1)) was tested in guppies infected with G. turnbulli. Prior acute toxicity tests revealed the maximum tolerance levels of guppies to garlic extract to be 12.5 mL L(-1) for 1h. Bathing of infected fish in garlic extract (7.5 and 12.5 mL L(-1)) significantly (pgarlic powder-supplemented diet were tested on guppies infected with G. turnbulli and Dactylogyrus sp. Fish were fed with food containing 10% and 20% dry garlic powder for 14 days. Groups fed with garlic supplemented diets showed significantly reduced (pgarlic did not appear to affect palatability. Fresh crushed garlic was added at a level of 1 gL(-1) and applied as an indefinite bath for 14 days. This treatment was seen to significantly reduce (pgarlic-fed group, as compared to control. These findings demonstrate the potential of garlic as a natural alternative to currently used chemical treatments for monogenean sp. infection in the guppy. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Phylogenetic profiles of all membrane transport proteins of the malaria parasite highlight new drug targets

    Directory of Open Access Journals (Sweden)

    January Weiner 3rd

    2016-08-01

    Full Text Available In order to combat the on-going malaria epidemic, discovery of new drug targets remains vital. Proteins that are essential to survival and specific to malaria parasites are key candidates. To survive within host cells, the parasites need to acquire nutrients and dispose of waste products across multiple membranes. Additionally, like all eukaryotes, they must redistribute ions and organic molecules between their various internal membrane bound compartments. Membrane transport proteins mediate all of these processes and are considered important mediators of drug resistance as well as drug targets in their own right. Recently, using advanced experimental genetic approaches and streamlined life cycle profiling, we generated a large collection of Plasmodium berghei gene deletion mutants and assigned essential gene functions, highlighting potential targets for prophylactic, therapeutic, and transmission-blocking anti-malarial drugs. Here, we present a comprehensive orthology assignment of all Plasmodium falciparum putative membrane transport proteins and provide a detailed overview of the associated essential gene functions obtained through experimental genetics studies in human and murine model parasites. Furthermore, we discuss the phylogeny of selected potential drug targets identified in our functional screen. We extensively discuss the results in the context of the functional assignments obtained using gene targeting available to date.

  15. Strategies for Minimizing Corruption in the Construction Industry in China

    Directory of Open Access Journals (Sweden)

    Patrick X.W. Zou

    2006-12-01

    Full Text Available Corruption is a social phenomenon deep rooted in the history of mankind. It is similar to other kinds of crime which are likely to occur in procurement of works by governments and local authorities, due to the large amount of money involved in a single transaction and the difficulty in monitoring project expenditure. Therefore, it is necessary to develop strategies to minimize any corruption risks and corrupt behaviour in procurement of construction projects. The aim of this paper is to review the current corruption prevention practices in China’s construction industry and suggest ways for improvement. To collect useful and insightful information, desktop studies, focus-group workshops and face-to-face interviews were conducted with supervisory and construction officers at different levels – state, province and municipal in China, who have direct responsibilities and experience in cracking down construction corruption. It was found that corruption happens in different forms during any stage of construction project procurement, and the current anti-corrupt practices are reactive rather than proactive. It was also found that improvements on the legal system, inspection strategies and processes, and promotion of ethical culture are all required. Based on the research findings, corruption prevention strategies were developed. The paper concludes that institution of random and regular checks, severe punishment and prosecution to corrupt personnel, and promotion of a healthy and clean construction culture are all necessary to mitigate the scourge.

  16. Status and prospects of DNA barcoding in medically important parasites and vectors.

    Science.gov (United States)

    Ondrejicka, Danielle A; Locke, Sean A; Morey, Kevin; Borisenko, Alex V; Hanner, Robert H

    2014-12-01

    For over 10 years, DNA barcoding has been used to identify specimens and discern species. Its potential benefits in parasitology were recognized early, but its utility and uptake remain unclear. Here we review studies using DNA barcoding in parasites and vectors affecting humans and find that the technique is accurate (accords with author identifications based on morphology or other markers) in 94-95% of cases, although aspects of DNA barcoding (vouchering, marker implicated) have often been misunderstood. In a newly compiled checklist of parasites, vectors, and hazards, barcodes are available for 43% of all 1403 species and for more than half of 429 species of greater medical importance. This is encouraging coverage that would improve with an active campaign targeting parasites and vectors. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Niche construction game cancer cells play.

    Science.gov (United States)

    Bergman, Aviv; Gligorijevic, Bojana

    2015-10-01

    Niche construction concept was originally defined in evolutionary biology as the continuous interplay between natural selection via environmental conditions and the modification of these conditions by the organism itself. Processes unraveling during cancer metastasis include construction of niches, which cancer cells use towards more efficient survival, transport into new environments and preparation of the remote sites for their arrival. Many elegant experiments were done lately illustrating, for example, the premetastatic niche construction, but there is practically no mathematical modeling done which would apply the niche construction framework. To create models useful for understanding niche construction role in cancer progression, we argue that a) genetic, b) phenotypic and c) ecological levels are to be included. While the model proposed here is phenomenological in its current form, it can be converted into a predictive outcome model via experimental measurement of the model parameters. Here we give an overview of an experimentally formulated problem in cancer metastasis and propose how niche construction framework can be utilized and broadened to model it. Other life science disciplines, such as host-parasite coevolution, may also benefit from niche construction framework adaptation, to satisfy growing need for theoretical considerations of data collected by experimental biology.

  18. Niche construction game cancer cells play

    Science.gov (United States)

    Bergman, Aviv; Gligorijevic, Bojana

    2015-10-01

    Niche construction concept was originally defined in evolutionary biology as the continuous interplay between natural selection via environmental conditions and the modification of these conditions by the organism itself. Processes unraveling during cancer metastasis include construction of niches, which cancer cells use towards more efficient survival, transport into new environments and preparation of the remote sites for their arrival. Many elegant experiments were done lately illustrating, for example, the premetastatic niche construction, but there is practically no mathematical modeling done which would apply the niche construction framework. To create models useful for understanding niche construction role in cancer progression, we argue that a) genetic, b) phenotypic and c) ecological levels are to be included. While the model proposed here is phenomenological in its current form, it can be converted into a predictive outcome model via experimental measurement of the model parameters. Here we give an overview of an experimentally formulated problem in cancer metastasis and propose how niche construction framework can be utilized and broadened to model it. Other life science disciplines, such as host-parasite coevolution, may also benefit from niche construction framework adaptation, to satisfy growing need for theoretical considerations of data collected by experimental biology.

  19. Prevalence of intestinal parasites in Lorestan Province, West of Iran

    Directory of Open Access Journals (Sweden)

    Ebrahim Badparva

    2014-09-01

    Full Text Available Objective: To study the prevalence of intestinal parasites in Lorestan Province, West of Iran. Methods: This cross-sectional study was conducted on 2 838 stool samples in Khorramabad, Lorestan Province in 2013. Samples were examined by the several techniques. Results: The frequency of intestinal parasites was 465 (16.4% of which 188 (13.5% samples were for urban areas and 277 (19.2% for rural areas. Infection in rural areas was significantly higher than urban areas. Out of 465 infected samples, 456 (98% were contaminated with protozoan parasites and 9 (2% with helminthes. Infection in people who sometimes used the soap to wash hands was significantly more than those who always used soap (P<0.001. Infection in people with poor economic conditions was significantly more than the two groups with moderate and good economic conditions (P<0.001. Conclusions: Effective reasons for the reducing incidence of intestinal parasites in Lorestan Province could be the development of universities with more students led to increased awareness, improvement of the environment, increase of the ease of access to health care centers, increase of advertising in provincial mass media about health training, increased health culture, and dispose of sanitary waste properly.

  20. Rare species of fungi parasiting on algae. II. Parasites of Desmidiaceae

    Directory of Open Access Journals (Sweden)

    Joanna Z. Kadłubowska

    2014-08-01

    Full Text Available Investigations carried out on the Desmidiaceae revealed the following species of fungi parasitizing on desmids: Myzocytium megastomum, Lagenidium closterii, Ancylistes closterii and Rhizophydium globosum. Legenidium closterii is new in Poland. It is the first information of this species as a parasite on the algae from the genus Tetmemorus. Figures of sporangia of Rhizophydium globosum on Euastrum ansatum, Cosmarium botrytis, C. pseudamoenum and a resting spore on Staurastrum punctulatum are the first graphic documentation of this species.

  1. Geographical location and age affects the incidence of parasitic infestations in school children

    Directory of Open Access Journals (Sweden)

    Rayan Paran

    2010-07-01

    Full Text Available Environmental factors affect the dissemination and distribution of intestinal parasites in human communities. To comprehend the prevalence of parasitic infestation and to examine whether geographical location and age also influence the prevalence of infection, fecal samples from 195 school children (rural = 95; male = 39; female = 56 (urban = 100; male = 60; female = 40 of five age groups ranging from 5 to 11 years in two different socio-economic zones (rural and urban were screened for specific intestinal parasites using standard histological techniques. Percentage incidences of parasitic species found in fecal wet mounts and concentrates in rural children were Entamoeba coli (25.3%, Giardia lamblia (17.9%, Blastocystis hominis (14.7%, Entamoeba histolytica (4.2%, Iodamoeba butschlii (1.1%, Hymenolepis nana (1.1% and Ascaris lumbricoides (1.1%. Whereas the percentage incidences among urban children were E. coli (26%, A. lumbricoides (21%, B. hominis (18%, G. lamblia (14%, T. trichiura (8%, I. butschlii (4% and A. duodenale (1%. Such findings may be related to dietary differences, living conditions and the greater use of natural anti-helminthic medicinal plants in rural communities. These results are important for both epidemiological data collection and for correlating dietary differences to intestinal parasitic diseases. Aims: We chose to investigate whether geographical location and age affect the prevalence and distribution of intestinal parasites among school children from two separate regions (rural and urban in areas surrounding, Chennai, Tamil Nadu, India. Settings and Design: A study of the prevalence of parasitic infestations was undertaken among primary school children, in rural and urban communities around Chennai, Tamil Nadu, India. Materials and Methods: Faecal sample collection, direct microscopic techniques, macroscopic examination and concentration techniques for identifying the parasites. Statistical analysis used: Percentage

  2. Anti-parasitic activity of pelleted sainfoin (Onobrychis viciifolia) against Ostertagia ostertagi and Cooperia oncophora in calves

    DEFF Research Database (Denmark)

    Desrues, O.; Pena-Espinoza, Miguel Angel; Hansen, T. V.

    2016-01-01

    BACKGROUND: Increasing anthelmintic-resistance in nematodes of ruminants emphasises the need for sustainable parasite control. Condensed tannin-containing legume forages such as sainfoin (Onobrychis viciifolia) have shown promising anthelmintic properties in small ruminants but this has never been......) or concentrate and grass-clover hay (Group CO; n = 6, two pens). After 16 days of adaptation, all animals were experimentally infected with 10,000 and 66,000 third-stage larvae of Ostertagia ostertagi and Cooperia oncophora, respectively. Egg excretion, blood parameters and bodyweights were recorded throughout...

  3. Host-Parasite Interactions from the Inside: Plant Reproductive Ontogeny Drives Specialization in Parasitic Insects.

    Directory of Open Access Journals (Sweden)

    Thomas Boivin

    Full Text Available Host plant interactions are likely key drivers of evolutionary processes involved in the diversification of phytophagous insects. Granivory has received substantial attention for its crucial role in shaping the interaction between plants and their seed parasites, but fine-scale mechanisms explaining the role of host plant reproductive biology on specialization of seed parasites remain poorly described. In a comparative approach using plant histological techniques, we tested the hypotheses that different seed parasite species synchronize their life cycles to specific stages in seed development, and that the stage they target depends on major differences in seed development programs. In a pinaceous system, seed storage products are initiated before ovule fertilization and the wasps target the ovule's nucellus during megagametogenesis, a stage at which larvae may benefit from the by-products derived from both secreting cells and dying nucellar cells. In a cupressaceous system, oviposition activity peaks later, during embryogenesis, and the wasps target the ovule's megagametophyte where larvae may benefit from cell disintegration during embryogenesis. Our cytohistological approach shows for the first time how, despite divergent oviposition targets, different parasite species share a common strategy that consists of first competing for nutrients with developing plant structures, and then consuming these developed structures to complete their development. Our results support the prediction that seed developmental program is an axis for specialization in seed parasites, and that it could be an important parameter in models of their ecological and taxonomic divergence. This study provides the basis for further investigating the possibility of the link between plant ontogeny and pre-dispersal seed parasitism.

  4. The Prevalence of Intestinal Parasites in Children Attending Day–Care Centers in Yazd City, Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Hosein Anvari Tafti

    2014-07-01

    Results: In total 10 % of children harbored at least one type of intestinal parasite. The rates of infection were as follows: Blastocystis hominis 2.8%, Giardia lamblia 2.8%, Entamoeba coli 1.1%, Chilomastix mesnili 1.7%, Dientamoeba fragilis 1.1.%. Infection rate in male was 12.9% and in female it was 6.9%. The relationship between sex, age, anthropometric indicators, and parasitic infection was not statistically significant. A statistically significant difference was observed between infection, parents’ education and mothers' job (P<0.005. Conclusion: The results of this study, showed a considerable decrease in the rate of intestinal parasitic infections in comparison with other studies. This may be owing to the improvements in personal environment, and health which have occurred through public education campaigns, health information raising, sanitation facilities improvement, proper waste and wastewater disposal, control of drinking-water, and food safety.

  5. Parasites and steroid hormones: corticosteroid and sex steroid synthesis, their role in the parasite physiology and development.

    Directory of Open Access Journals (Sweden)

    Marta C. Romano

    2015-06-01

    Full Text Available In many cases parasites display highly complex life cycles that include establishment of the larva or adults within host organs, but even in those that have only one host reciprocal intricate interactions occur. A bulk of evidence indicates that steroid hormones influence the development and course of parasitic infections, the host gender susceptibility to the infection and the associate differences in immunological response are good examples of the host-parasite interplay. However, the capacity of these organisms to synthesize their own steroidogenic hormones still has more questions than answers. It is now well known that many parasites synthesize ecdysteroids, but limited information is available on sex steroid and corticosteroid synthesis. This review intends to summarize some of the existing information in the field. In many but not all parasitosis the host hormonal environment determines the susceptibility, the course and severity of parasite infections. In most cases the infection disturbs the host environment, and activate immune responses that finally affect the endocrine system. Furthermore, sex steroids and corticosteroids may also directly modify the parasite reproduction and molting. Available information indicates that parasites synthesize some steroid hormones like ecdysteroids and sex steroids and the presence and activity of related enzymes have been demonstrated. More recently, the synthesis of corticosteroid like compounds has been shown in Taenia solium and tapeworms and in Taenia crassiceps WFU cysticerci. Deeper knowledge of the endocrine properties of parasites will contribute to understand their reproduction and reciprocal interactions with the host, and also may contribute to design tools to combat the infection in some clinical situations.

  6. Improving Productivity in Building Construction – by Repetitions in Products, Processes, and Organisations

    DEFF Research Database (Denmark)

    Bekdik, Baris

    This thesis builds on several studies with connection to the lack of productivity in build-ing construction. It seeks to enhance the conditions for improving productivity in the fragmented building construction industry, by exploring how a modular thinking of products, processes and organisations...... can be reapplied on new building construction projects. Complexity theory is used for diagnosis and modularity theory for the remedy towards the high degree of complexity, which is seen as the root of unproductivity. De-sign Research Methodology is followed to structure and organise the different...... from the practitioner’s perspective. In the second part of the exploratory study, examples of the fragmented kinds of modu-lar applications around the world are compiled in order to demonstrate the inconsistent use, but still universal appeal that the approach carries with respect to building construc-tion...

  7. Update on pathology of ocular parasitic disease.

    Science.gov (United States)

    Das, Dipankar; Ramachandra, Varsha; Islam, Saidul; Bhattacharjee, Harsha; Biswas, Jyotirmay; Koul, Akanksha; Deka, Panna; Deka, Apurba

    2016-11-01

    Parasites are a group of eukaryotic organisms that may be free-living or form a symbiotic or parasitic relationship with the hosts. Consisting of over 800,000 recognized species, parasites may be unicellular (Protozoa) or multicellular (helminths and arthropods). The association of parasites with human population started long before the emergence of civilization. Parasitic zoonotic diseases are prevalent worldwide including India. Appropriate epidemiological data are lacking on existing zoonotic parasitic diseases, and newer diseases are emerging in our scenario. Systemic diseases such as cysticercosis, paragonimiasis, hydatidosis, and toxoplasmosis are fairly common. Acquired Toxoplasma infections are rising in immune-deficient individuals. Amongst the ocular parasitic diseases, various protozoas such as Cystoidea, trematodes, tissue flagellates, sporozoas etc. affect humans in general and eyes in particular, in different parts of the world. These zoonoses seem to be a real health related problem globally. Recent intensification of research throughout the world has led to specialization in biological fields, creating a conducive situation for researchers interested in this subject. The basics of parasitology lie in morphology, pathology, and with recent updates in molecular parasitology, the scope has extended further. The current review is to address the recent update in ophthalmic parasites with special reference to pathology and give a glimpse of further research in this field.

  8. Considering RNAi experimental design in parasitic helminths.

    Science.gov (United States)

    Dalzell, Johnathan J; Warnock, Neil D; McVeigh, Paul; Marks, Nikki J; Mousley, Angela; Atkinson, Louise; Maule, Aaron G

    2012-04-01

    Almost a decade has passed since the first report of RNA interference (RNAi) in a parasitic helminth. Whilst much progress has been made with RNAi informing gene function studies in disparate nematode and flatworm parasites, substantial and seemingly prohibitive difficulties have been encountered in some species, hindering progress. An appraisal of current practices, trends and ideals of RNAi experimental design in parasitic helminths is both timely and necessary for a number of reasons: firstly, the increasing availability of parasitic helminth genome/transcriptome resources means there is a growing need for gene function tools such as RNAi; secondly, fundamental differences and unique challenges exist for parasite species which do not apply to model organisms; thirdly, the inherent variation in experimental design, and reported difficulties with reproducibility undermine confidence. Ideally, RNAi studies of gene function should adopt standardised experimental design to aid reproducibility, interpretation and comparative analyses. Although the huge variations in parasite biology and experimental endpoints make RNAi experimental design standardization difficult or impractical, we must strive to validate RNAi experimentation in helminth parasites. To aid this process we identify multiple approaches to RNAi experimental validation and highlight those which we deem to be critical for gene function studies in helminth parasites.

  9. Parasitic nematode interactions with mammals and plants.

    Science.gov (United States)

    Jasmer, Douglas P; Goverse, Aska; Smant, Geert

    2003-01-01

    Parasitic nematodes that infect humans, animals, and plants cause serious diseases that are deleterious to human health and agricultural productivity. Chemical and biological control methods have reduced the impact of these parasites. However, surviving environmental stages lead to persistent reinfection of host species. In addition, development of resistance to nematicides and anthelmintics by these parasites and reduced availability of some nematicides, for environmental protection, pose significant obstacles for current and future prospects of effective parasite control. Due to marked differences in host species, research on animal and plant parasitic nematodes often proceeds independently. Despite the differences between animals and plants, basic cellular properties are shared among these host organisms. Some common properties may be important for mechanisms [homologous or convergent (homoplastic)] by which nematodes successfully infect these diverse hosts or by which animal and plant hosts resist infections by these pathogens. Here we compare host/parasite interactions between plant parasitic nematodes (PPN) and animal parasitic nematodes, with an emphasis on mammalian hosts (MPN). Similarities and differences are considered in the context of progress on molecular dissection of these interactions. A comprehensive coverage is not possible in the space allotted. Instead, an illustrative approach is used to establish examples that, it is hoped, exemplify the value of the comparative approach.

  10. Update on pathology of ocular parasitic disease

    Directory of Open Access Journals (Sweden)

    Dipankar Das

    2016-01-01

    Full Text Available Parasites are a group of eukaryotic organisms that may be free-living or form a symbiotic or parasitic relationship with the hosts. Consisting of over 800,000 recognized species, parasites may be unicellular (Protozoa or multicellular (helminths and arthropods. The association of parasites with human population started long before the emergence of civilization. Parasitic zoonotic diseases are prevalent worldwide including India. Appropriate epidemiological data are lacking on existing zoonotic parasitic diseases, and newer diseases are emerging in our scenario. Systemic diseases such as cysticercosis, paragonimiasis, hydatidosis, and toxoplasmosis are fairly common. Acquired Toxoplasma infections are rising in immune-deficient individuals. Amongst the ocular parasitic diseases, various protozoas such as Cystoidea, trematodes, tissue flagellates, sporozoas etc. affect humans in general and eyes in particular, in different parts of the world. These zoonoses seem to be a real health related problem globally. Recent intensification of research throughout the world has led to specialization in biological fields, creating a conducive situation for researchers interested in this subject. The basics of parasitology lie in morphology, pathology, and with recent updates in molecular parasitology, the scope has extended further. The current review is to address the recent update in ophthalmic parasites with special reference to pathology and give a glimpse of further research in this field.

  11. Parasite stress promotes homicide and child maltreatment

    Science.gov (United States)

    Thornhill, Randy; Fincher, Corey L.

    2011-01-01

    Researchers using the parasite-stress theory of human values have discovered many cross-cultural behavioural patterns that inform a range of scholarly disciplines. Here, we apply the theory to major categories of interpersonal violence, and the empirical findings are supportive. We hypothesize that the collectivism evoked by high parasite stress is a cause of adult-on-adult interpersonal violence. Across the US states, parasite stress and collectivism each positively predicts rates of men's and women's slaying of a romantic partner, as well as the rate of male-honour homicide and of the motivationally similar felony-related homicide. Of these four types of homicide, wealth inequality has an independent effect only on rates of male-honour and felony-related homicide. Parasite stress and collectivism also positively predict cross-national homicide rates. Child maltreatment by caretakers is caused, in part, by divestment in offspring of low phenotypic quality, and high parasite stress produces more such offspring than low parasite stress. Rates of each of two categories of the child maltreatment—lethal and non-lethal—across the US states are predicted positively by parasite stress, with wealth inequality and collectivism having limited effects. Parasite stress may be the strongest predictor of interpersonal violence to date. PMID:22042922

  12. Gastrointestinal parasite infection of the Gray mouse lemur ...

    African Journals Online (AJOL)

    Faecal material from 169 individuals of Microcebus murinus living in five littoral forest fragments was analyzed for gastrointestinal parasites. The fragments differed in size and forest quality. Gastrointestinal parasite infection of M. murinus was characterised using parasite species richness, the prevalence of parasites, and ...

  13. Mechanisms of CNS invasion and damage by parasites.

    Science.gov (United States)

    Kristensson, Krister; Masocha, Willias; Bentivoglio, Marina

    2013-01-01

    Invasion of the central nervous system (CNS) is a most devastating complication of a parasitic infection. Several physical and immunological barriers provide obstacles to such an invasion. In this broad overview focus is given to the physical barriers to neuroinvasion of parasites provided at the portal of entry of the parasites, i.e., the skin and epithelial cells of the gastrointestinal tract, and between the blood and the brain parenchyma, i.e., the blood-brain barrier (BBB). A description is given on how human pathogenic parasites can reach the CNS via the bloodstream either as free-living or extracellular parasites, by embolization of eggs, or within red or white blood cells when adapted to intracellular life. Molecular mechanisms are discussed by which parasites can interact with or pass across the BBB. The possible targeting of the circumventricular organs by parasites, as well as the parasites' direct entry to the brain from the nasal cavity through the olfactory nerve pathway, is also highlighted. Finally, examples are given which illustrate different mechanisms by which parasites can cause dysfunction or damage in the CNS related to toxic effects of parasite-derived molecules or to immune responses to the infection. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Diagnosis of Parasitic Diseases: Old and New Approaches

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    Momar Ndao

    2009-01-01

    Full Text Available Methods for the diagnosis of infectious diseases have stagnated in the last 20–30 years. Few major advances in clinical diagnostic testing have been made since the introduction of PCR, although new technologies are being investigated. Many tests that form the backbone of the “modern” microbiology laboratory are based on very old and labour-intensive technologies such as microscopy for malaria. Pressing needs include more rapid tests without sacrificing sensitivity, value-added tests, and point-of-care tests for both high- and low-resource settings. In recent years, research has been focused on alternative methods to improve the diagnosis of parasitic diseases. These include immunoassays, molecular-based approaches, and proteomics using mass spectrometry platforms technology. This review summarizes the progress in new approaches in parasite diagnosis and discusses some of the merits and disadvantages of these tests.

  15. Solidarity, authenticity and anti racism

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    Dinesh Wadiwel

    2009-08-01

    Full Text Available Anti Racist struggles often aim to construct alliances between groups under the banner of "solidarity" in order to achieve change. Using Foucault's Society Must be Defended lectures as a basis, this paper interrogates the difficulties associated with creating solidarity in anti racist movements, when conflict and war might be treated as the basis for racial stratifications. Following from this, it is argued that friendships in spite of differences are possible under the guise of "truce": that is through allegiances that begin by acknowledging the fact of war.

  16. Antibodies to ribosomal P proteins of Trypanosoma cruzi in Chagas disease possess functional autoreactivity with heart tissue and differ from anti-P autoantibodies in lupus.

    Science.gov (United States)

    Kaplan, D; Ferrari, I; Bergami, P L; Mahler, E; Levitus, G; Chiale, P; Hoebeke, J; Van Regenmortel, M H; Levin, M J

    1997-09-16

    Anti-P antibodies present in sera from patients with chronic Chagas heart disease (cChHD) recognize peptide R13, EEEDDDMGFGLFD, which encompasses the C-terminal region of the Trypanosoma cruzi ribosomal P1 and P2 proteins. This peptide shares homology with the C-terminal region (peptide H13 EESDDDMGFGLFD) of the human ribosomal P proteins, which is in turn the target of anti-P autoantibodies in systemic lupus erythematosus (SLE), and with the acidic epitope, AESDE, of the second extracellular loop of the beta1-adrenergic receptor. Anti-P antibodies from chagasic patients showed a marked preference for recombinant parasite ribosomal P proteins and peptides, whereas anti-P autoantibodies from SLE reacted with human and parasite ribosomal P proteins and peptides to the same extent. A semi-quantitative estimation of the binding of cChHD anti-P antibodies to R13 and H13 using biosensor technology indicated that the average affinity constant was about 5 times higher for R13 than for H13. Competitive enzyme immunoassays demonstrated that cChHD anti-P antibodies bind to the acidic portions of peptide H13, as well as to peptide H26R, encompassing the second extracellular loop of the beta1 adrenoreceptor. Anti-P antibodies isolated from cChHD patients exert a positive chronotropic effect in vitro on cardiomyocytes from neonatal rats, which resembles closely that of anti-beta1 receptor antibodies isolated from the same patient. In contrast, SLE anti-P autoantibodies have no functional effect. Our results suggest that the adrenergic-stimulating activity of anti-P antibodies may be implicated in the induction of functional myocardial impairments observed in cChHD.

  17. Old Yellow Enzyme from Trypanosoma cruzi Exhibits In Vivo Prostaglandin F2α Synthase Activity and Has a Key Role in Parasite Infection and Drug Susceptibility

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    Florencia Díaz-Viraqué

    2018-03-01

    Full Text Available The discovery that trypanosomatids, unicellular organisms of the order Kinetoplastida, are capable of synthesizing prostaglandins raised questions about the role of these molecules during parasitic infections. Multiple studies indicate that prostaglandins could be related to the infection processes and pathogenesis in trypanosomatids. This work aimed to unveil the role of the prostaglandin F2α synthase TcOYE in the establishment of Trypanosoma cruzi infection, the causative agent of Chagas disease. This chronic disease affects several million people in Latin America causing high morbidity and mortality. Here, we propose a prokaryotic evolutionary origin for TcOYE, and then we used in vitro and in vivo experiments to show that T. cruzi prostaglandin F2α synthase plays an important role in modulating the infection process. TcOYE overexpressing parasites were less able to complete the infective cycle in cell culture infections and increased cardiac tissue parasitic load in infected mice. Additionally, parasites overexpressing the enzyme increased PGF2α synthesis from arachidonic acid. Finally, an increase in benznidazole and nifurtimox susceptibility in TcOYE overexpressing parasites showed its participation in activating the currently anti-chagasic drugs, which added to its observed ability to confer resistance to hydrogen peroxide, highlights the relevance of this enzyme in multiple events including host–parasite interaction.

  18. Comparison between Two Decades of Prevalence of Intestinal Parasitic Diseases and Risk Factors in a Brazilian Urban Centre

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    Maria Aparecida Alves de Oliveira Serra

    2015-01-01

    Full Text Available Objectives. This study’s objective was to compare the prevalence of intestinal parasites and associated risk factors in children in urban communities, in the Brazilian Northeast, between two decades. Methods. This quantitative transversal study consisted of a comparative analysis of two different samples: the first viewing the years 1992–1996 and the other through a coproepidemiological data survey undertaken in 2010-2011. Results. It was evidenced that there was a reduction of intestinal parasites and that there were improvements in the socioenvironmental conditions between the two decades evaluated. It was observed that, in the period 1992–1996, playing out in the streets was associated with a higher risk for acquiring intestinal parasites. Over the 2010-2011 period, the characteristics of more than five residents per household, houses with dirt floors, children who live in homes without piped water, and children who play out in the streets were associated with a higher risk of intestinal parasitic infection. Conclusion. The study showed a reduction of intestinal parasitic diseases to 23.8% in 2010-2011 from 81.3% in 1992–1996 and improvement of the social-sanitary conditions of the population between the decades analyzed.

  19. Cyclosporin A treatment of Leishmania donovani reveals stage-specific functions of cyclophilins in parasite proliferation and viability.

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    Wai-Lok Yau

    Full Text Available BACKGROUND: Cyclosporin A (CsA has important anti-microbial activity against parasites of the genus Leishmania, suggesting CsA-binding cyclophilins (CyPs as potential drug targets. However, no information is available on the genetic diversity of this important protein family, and the mechanisms underlying the cytotoxic effects of CsA on intracellular amastigotes are only poorly understood. Here, we performed a first genome-wide analysis of Leishmania CyPs and investigated the effects of CsA on host-free L. donovani amastigotes in order to elucidate the relevance of these parasite proteins for drug development. METHODOLOGY/PRINCIPAL FINDINGS: Multiple sequence alignment and cluster analysis identified 17 Leishmania CyPs with significant sequence differences to human CyPs, but with highly conserved functional residues implicated in PPIase function and CsA binding. CsA treatment of promastigotes resulted in a dose-dependent inhibition of cell growth with an IC50 between 15 and 20 microM as demonstrated by proliferation assay and cell cycle analysis. Scanning electron microscopy revealed striking morphological changes in CsA treated promastigotes reminiscent to developing amastigotes, suggesting a role for parasite CyPs in Leishmania differentiation. In contrast to promastigotes, CsA was highly toxic to amastigotes with an IC50 between 5 and 10 microM, revealing for the first time a direct lethal effect of CsA on the pathogenic mammalian stage linked to parasite thermotolerance, independent from host CyPs. Structural modeling, enrichment of CsA-binding proteins from parasite extracts by FPLC, and PPIase activity assays revealed direct interaction of the inhibitor with LmaCyP40, a bifunctional cyclophilin with potential co-chaperone function. CONCLUSIONS/SIGNIFICANCE: The evolutionary expansion of the Leishmania CyP protein family and the toxicity of CsA on host-free amastigotes suggest important roles of PPIases in parasite biology and implicate

  20. Anti-Neospora caninum and anti-Sarcocystis spp. specific antibodies cross-react with Besnoitia besnoiti and influence the serological diagnosis of bovine besnoitiosis.

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    García-Lunar, P; Moré, G; Campero, L; Ortega-Mora, L M; Álvarez-García, G

    2015-11-30

    Bovine besnoitiosis control remains a challenge because the disease continues to spread and control relies solely on accurate diagnosis coupled to management measures. However, recent studies have reported that routinely used ELISAs may raise a high number of false-positive results. Herein, cross-reactions between Besnoitia besnoiti antigens and anti-Neospora caninum and/or anti-Sarcocystis spp.-specific antibodies were studied in an in house ELISA since N. caninum and Sarcocystis spp. are closely related parasites, and both infections are highly prevalent in cattle worldwide. The serum panel was composed of the following categories: sera from B. besnoiti-seronegative (n=75) and -seropositive cattle (n=66), B. besnoiti-based-ELISA false-positive reactors (n=96) together with N. caninum (n=36) and Sarcocystis spp. (n=42) -seropositive reference cattle sera. B. besnoiti tachyzoite based western blot (WB) results classified animals as seropositive or seronegative. Sera were analyzed for the detection of anti-N. caninum by WB and ELISA and anti-Sarcocystis spp.-specific antibodies by WB and IFAT. Those samples recognizing a Sarcocystis spp. 18-20 kDa antigenic region and N. caninum 17-18 kDa immunodominant antigen were considered to be Sarcocystis spp. and N. caninum seropositive, respectively. The category of B. besnoiti based-ELISA false-positive reactors showed the highest number of sera with specific anti-Sarcocystis spp. and anti-N. caninum antibodies (74%; 71/96), followed by the N. caninum-seropositive cattle category (52.8%; 19/36). In contrast, few B. besnoiti-seronegative and -seropositive cattle showed antibodies against Sarcocystis spp. and N. caninum (10.7%; 8/75 and 1.5%; 1/66), respectively). This study revealed that B. besnoiti false-positive ELISA results were associated not only with the presence of anti-N. caninum and anti-Sarcocystis spp. antibodies (χ(2): 78.36; pbovine besnoitiosis. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. An Improved Multiobjective PSO for the Scheduling Problem of Panel Block Construction

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    Zhi Yang

    2016-01-01

    Full Text Available Uncertainty is common in ship construction. However, few studies have focused on scheduling problems under uncertainty in shipbuilding. This paper formulates the scheduling problem of panel block construction as a multiobjective fuzzy flow shop scheduling problem (FSSP with a fuzzy processing time, a fuzzy due date, and the just-in-time (JIT concept. An improved multiobjective particle swarm optimization called MOPSO-M is developed to solve the scheduling problem. MOPSO-M utilizes a ranked-order-value rule to convert the continuous position of particles into the discrete permutations of jobs, and an available mapping is employed to obtain the precedence-based permutation of the jobs. In addition, to improve the performance of MOPSO-M, archive maintenance is combined with global best position selection, and mutation and a velocity constriction mechanism are introduced into the algorithm. The feasibility and effectiveness of MOPSO-M are assessed in comparison with general MOPSO and nondominated sorting genetic algorithm-II (NSGA-II.

  2. New mechanisms of disease and parasite-host interactions.

    Science.gov (United States)

    de Souza, Tiago Alves Jorge; de Carli, Gabriel Jose; Pereira, Tiago Campos

    2016-09-01

    An unconventional interaction between a patient and parasites was recently reported, in which parasitic cells invaded host's tissues, establishing several tumors. This finding raises various intriguing hypotheses on unpredicted forms of interplay between a patient and infecting parasites. Here we present four unusual hypothetical host-parasite scenarios with intriguing medical consequences. Relatively simple experimental designs are described in order to evaluate such hypotheses. The first one refers to the possibility of metabolic disorders in parasites intoxicating the host. The second one is on possibility of patients with inborn errors of metabolism (IEM) being more resistant to parasites (due to accumulation of toxic compounds in the bloodstream). The third one refers to a mirrored scenario: development of tumors in parasites due to ingestion of host's circulating cancer cells. The last one describes a complex relationship between parasites accumulating a metabolite and supplying it to a patient with an IEM. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Antibody expressing pea seeds as fodder for prevention of gastrointestinal parasitic infections in chickens

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    Macek Jeanette

    2009-09-01

    Full Text Available Abstract Background Coccidiosis caused by protozoans of genus Eimeria is a chicken parasitic disease of great economical importance. Conventional disease control strategies depend on vaccination and prophylactic use of anticoccidial drugs. Alternative solution to prevent and treat coccidiosis could be provided by passive immunization using orally delivered neutralizing antibodies. We investigated the possibility to mitigate the parasitic infection by feeding poultry with antibody expressing transgenic crop seeds. Results Using the phage display antibody library, we generated a panel of anti-Eimeria scFv antibody fragments with high sporozoite-neutralizing activity. These antibodies were expressed either transiently in agrobacteria-infiltrated tobacco leaves or stably in seeds of transgenic pea plants. Comparison of the scFv antibodies purified either from tobacco leaves or from the pea seeds demonstrated no difference in their antigen-binding activity and molecular form compositions. Force-feeding experiments demonstrated that oral delivery of flour prepared from the transgenic pea seeds had higher parasite neutralizing activity in vivo than the purified antibody fragments isolated from tobacco. The pea seed content was found to protect antibodies against degradation by gastrointestinal proteases (>100-fold gain in stability. Ad libitum feeding of chickens demonstrated that the transgenic seeds were well consumed and not shunned. Furthermore, feeding poultry with shred prepared from the antibody expressing pea seeds led to significant mitigation of infection caused both by high and low challenge doses of Eimeria oocysts. Conclusion The results suggest that our strategy offers a general approach to control parasitic infections in production animals using cost-effective antibody expression in crop seeds affordable for the animal health market.

  4. Hepatozoon parasites (Apicomplexa: Adeleorina) in bats.

    Science.gov (United States)

    Pinto, C Miguel; Helgen, Kristofer M; Fleischer, Robert C; Perkins, Susan L

    2013-08-01

    We provide the first evidence of Hepatozoon parasites infecting bats. We sequenced a short fragment of the 18S rRNA gene (~600 base pairs) of Hepatozoon parasites from 3 Hipposideros cervinus bats from Borneo. Phylogenies inferred by model-based methods place these Hepatozoon within a clade formed by parasites of reptiles, rodents, and marsupials. We discuss the scenario that bats might be common hosts of Hepatozoon.

  5. The perturbative construction of Symanzik's improved action for Φ44 and QED4

    International Nuclear Information System (INIS)

    Keller, G.

    1993-01-01

    For the perturbative Euclidean massive Φ 4 4 and QED 4 (with a small photon mass) an explicit construction of Symanzik's improved action is presented. It is established rigorously that all the Green functions exhibit improved convergence as the momentum space UV cutoff is sent to infinity. These results are obtained by an application of the powerful yet technically simple flow equation method. (orig.)

  6. Mechanisms of stage-transcending protection following immunization of mice with late liver stage-arresting genetically attenuated malaria parasites.

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    Brandon K Sack

    2015-05-01

    Full Text Available Malaria, caused by Plasmodium parasite infection, continues to be one of the leading causes of worldwide morbidity and mortality. Development of an effective vaccine has been encumbered by the complex life cycle of the parasite that has distinct pre-erythrocytic and erythrocytic stages of infection in the mammalian host. Historically, malaria vaccine development efforts have targeted each stage in isolation. An ideal vaccine, however, would target multiple life cycle stages with multiple arms of the immune system and be capable of eliminating initial infection in the liver, the subsequent blood stage infection, and would prevent further parasite transmission. We have previously shown that immunization of mice with Plasmodium yoelii genetically attenuated parasites (GAP that arrest late in liver stage development elicits stage-transcending protection against both a sporozoite challenge and a direct blood stage challenge. Here, we show that this immunization strategy engenders both T- and B-cell responses that are essential for stage-transcending protection, but the relative importance of each is determined by the host genetic background. Furthermore, potent anti-blood stage antibodies elicited after GAP immunization rely heavily on FC-mediated functions including complement fixation and FC receptor binding. These protective antibodies recognize the merozoite surface but do not appear to recognize the immunodominant merozoite surface protein-1. The antigen(s targeted by stage-transcending immunity are present in both the late liver stages and blood stage parasites. The data clearly show that GAP-engendered protective immune responses can target shared antigens of pre-erythrocytic and erythrocytic parasite life cycle stages. As such, this model constitutes a powerful tool to identify novel, protective and stage-transcending T and B cell targets for incorporation into a multi-stage subunit vaccine.

  7. Parasitism, personality and cognition in fish.

    Science.gov (United States)

    Barber, I; Mora, A B; Payne, E M; Weinersmith, K L; Sih, A

    2017-08-01

    It is well established that parasites can have profound effects on the behaviour of host organisms, and that individual differences in behaviour can influence susceptibility to parasite infections. Recently, two major themes of research have developed. First, there has been a growing interest in the proximate, mechanistic processes underpinning parasite-associated behaviour change, and the interactive roles of the neuro-, immune, and other physiological systems in determining relationships between behaviour and infection susceptibility. Secondly, as the study of behaviour has shifted away from one-off measurements of single behaviours and towards a behavioural syndromes/personality framework, research is starting to focus on the consequences of parasite infection for temporal and contextual consistency of behaviour, and on the implications of different personality types for infection susceptibility. In addition, there is increasing interest in the potential for relationships between cognition and personality to also have implications for host-parasite interactions. As models well-suited to both the laboratory study of behaviour and experimental parasitology, teleost fish have been used as hosts in many of these studies. In this review we provide a broad overview of the range of mechanisms that potentially generate links between fish behaviour, personality, and parasitism, and illustrate these using examples drawn from the recent literature. In addition, we examine the potential interactions between cognition, personality and parasitism, and identify questions that may be usefully investigated with fish models. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. The origin of malarial parasites in orangutans.

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    M Andreína Pacheco

    Full Text Available BACKGROUND: Recent findings of Plasmodium in African apes have changed our perspectives on the evolution of malarial parasites in hominids. However, phylogenetic analyses of primate malarias are still missing information from Southeast Asian apes. In this study, we report molecular data for a malaria parasite lineage found in orangutans. METHODOLOGY/PRINCIPAL FINDINGS: We screened twenty-four blood samples from Pongo pygmaeus (Kalimantan, Indonesia for Plasmodium parasites by PCR. For all the malaria positive orangutan samples, parasite mitochondrial genomes (mtDNA and two antigens: merozoite surface protein 1 42 kDa (MSP-1(42 and circumsporozoite protein gene (CSP were amplified, cloned, and sequenced. Fifteen orangutans tested positive and yielded 5 distinct mitochondrial haplotypes not previously found. The haplotypes detected exhibited low genetic divergence among them, indicating that they belong to one species. We report phylogenetic analyses using mitochondrial genomes, MSP-1(42 and CSP. We found that the orangutan malaria parasite lineage was part of a monophyletic group that includes all the known non-human primate malaria parasites found in Southeast Asia; specifically, it shares a recent common ancestor with P. inui (a macaque parasite and P. hylobati (a gibbon parasite suggesting that this lineage originated as a result of a host switch. The genetic diversity of MSP-1(42 in orangutans seems to be under negative selection. This result is similar to previous findings in non-human primate malarias closely related to P. vivax. As has been previously observed in the other Plasmodium species found in non-human primates, the CSP shows high polymorphism in the number of repeats. However, it has clearly distinctive motifs from those previously found in other malarial parasites. CONCLUSION: The evidence available from Asian apes indicates that these parasites originated independently from those found in Africa, likely as the result of host

  9. Parasites in the Wadden Sea food web

    Science.gov (United States)

    Thieltges, David W.; Engelsma, Marc Y.; Wendling, Carolin C.; Wegner, K. Mathias

    2013-09-01

    While the free-living fauna of the Wadden Sea has received much interest, little is known on the distribution and effects of parasites in the Wadden Sea food web. However, recent studies on this special type of trophic interaction indicate a high diversity of parasites in the Wadden Sea and suggest a multitude of effects on the hosts. This also includes effects on specific predator-prey relationships and the general structure of the food web. Focussing on molluscs, a major group in the Wadden Sea in terms of biomass and abundance and an important link between primary producers and predators, we review existing studies and exemplify the ecological role of parasites in the Wadden Sea food web. First, we give a brief inventory of parasites occurring in the Wadden Sea, ranging from microparasites (e.g. protozoa, bacteria) to macroparasites (e.g. helminths, parasitic copepods) and discuss the effects of spatial scale on heterogeneities in infection levels. We then demonstrate how parasites can affect host population dynamics by acting as a strong mortality factor, causing mollusc mass mortalities. In addition, we will exemplify how parasites can mediate the interaction strength of predator-prey relationships and affect the topological structure of the Wadden Sea food web as a whole. Finally, we highlight some ongoing changes regarding parasitism in the Wadden Sea in the course of global change (e.g. species introduction, climate change) and identify important future research questions to entangle the role of parasites in the Wadden Sea food web.

  10. Parasite transmission in a natural multihost–multiparasite community

    Science.gov (United States)

    2017-01-01

    Understanding the transmission and dynamics of infectious diseases in natural communities requires understanding the extent to which the ecology, evolution and epidemiology of those diseases are shaped by alternative hosts. We performed laboratory experiments to test how parasite spillover affected traits associated with transmission in two co-occurring parasites: the bacterium Pasteuria ramosa and the fungus Metschnikowia bicuspidata. Both parasites were capable of transmission from the reservoir host (Daphnia dentifera) to the spillover host (Ceriodaphnia dubia), but this occurred at a much higher rate for the fungus than the bacterium. We quantified transmission potential by combining information on parasite transmission and growth rate, and used this to compare parasite fitness in the two host species. For both parasites, transmission potential was lower in the spillover host. For the bacterium, virulence was higher in the spillover host. Transmission back to the original host was high for both parasites, with spillover influencing transmission rate of the fungus but not the bacterium. Thus, while inferior, the spillover host is not a dead-end for either parasite. Overall, our results demonstrate that the presence of multiple hosts in a community can have important consequences for disease transmission, and host and parasite fitness. This article is part of the themed issue ‘Opening the black box: re-examining the ecology and evolution of parasite transmission’. PMID:28289264

  11. Parasite transmission in a natural multihost-multiparasite community.

    Science.gov (United States)

    Auld, Stuart K J R; Searle, Catherine L; Duffy, Meghan A

    2017-05-05

    Understanding the transmission and dynamics of infectious diseases in natural communities requires understanding the extent to which the ecology, evolution and epidemiology of those diseases are shaped by alternative hosts. We performed laboratory experiments to test how parasite spillover affected traits associated with transmission in two co-occurring parasites: the bacterium Pasteuria ramosa and the fungus Metschnikowia bicuspidata Both parasites were capable of transmission from the reservoir host ( Daphnia dentifera ) to the spillover host ( Ceriodaphnia dubia ), but this occurred at a much higher rate for the fungus than the bacterium. We quantified transmission potential by combining information on parasite transmission and growth rate, and used this to compare parasite fitness in the two host species. For both parasites, transmission potential was lower in the spillover host. For the bacterium, virulence was higher in the spillover host. Transmission back to the original host was high for both parasites, with spillover influencing transmission rate of the fungus but not the bacterium. Thus, while inferior, the spillover host is not a dead-end for either parasite. Overall, our results demonstrate that the presence of multiple hosts in a community can have important consequences for disease transmission, and host and parasite fitness.This article is part of the themed issue 'Opening the black box: re-examining the ecology and evolution of parasite transmission'. © 2017 The Author(s).

  12. Status of gastrointestinal parasites in Red Panda of Nepal.

    Science.gov (United States)

    Bista, Damber; Shrestha, Saroj; Kunwar, Ajaya Jang; Acharya, Sakshi; Jnawali, Shant Raj; Acharya, Krishna Prasad

    2017-01-01

    Red pandas are known to be highly susceptible to endoparasites, which can have a prominent impact on the population dynamics of this endangered species. There are very limited published reports on prevalence and risk of parasites in wild populations of red panda, especially localized reports. This study attempts to provide an in-depth insight of the status of endoparasites in red pandas, which is critical for strengthening conservation efforts. A total of 272 fecal samples were collected through systematic sampling across the red panda distribution range in Nepal and coprological examination was completed using standard techniques. It was followed by an estimation of prevalence and mean intensity of parasites, as well as statistical analysis, which was carried out using R statistical software. Parasite prevalence was documented in 90.80% ( n  = 247) out of 272 samples examined which includes seven different species along with three genera of parasites belonging to Protozoans (3 species), Cestodes (1 genus, 1 species) and Nematodes (2 genera, 3 species). Nematodes predominated in all infected samples (87.62%). Prevalence of Ancyclostoma duodenale ( n  = 227, 70.06%), having a mean intensity of 3.45 ± 2.88 individuals per sample, was observed, followed by Ascaris lumbricoides ( n  = 19, 5.86%) and Entamoeba histolytica ( n  = 24, 7.41%). Eight variables for assessing the determinants of infestation were tested: protected areas; non-protected areas; aspect; elevation; slope; and distance to water sources, herding stations, and settlements. Only the settlement displayed significant association ( β = -1534e-04, t  =  - 2.192, p  = 0.0293) though each parasite species displayed dissimilar association with different variables. This study indicates the urgent need of improving existing herding practice through habitat zonation, rotational grazing, medication of livestock, and prohibition of open defecation within and around red panda habitat.

  13. Gastrointestinal function in the parasitized host

    International Nuclear Information System (INIS)

    Castro, G.A.

    1981-01-01

    Emphasis in this review is on (1) digestive-absorptive, secretory and smooth muscle functions altered by gastrointestinal (GI) parasites, (2) mechanisms by which parasites induce changes, and (3) the influence of parasite-induced alterations on the health of the host. Examples involving laboratory and domestic animals indicate that inflammation is an important factor in pathological alterations in epithelial and smooth muscle tissues throughout the alimentary canal. Observations on GI secretory activity reveal an influence of parasites on the host GI endocrine system. It is argued that assessments of the significance of parasite-induced changes on the host must be balanced with the adaptive potential and 'reserve capacity' of the GI system. In this regard host immunity should be considered a specific adaptation. Some tracer studies are mentioned marginally, such as the use of 14 C polyethylene glycol to estimate the direction of not fluid movement in the small intestine, and the use of 51 Cr to demonstrate the significantly faster intestinal transit in Trichinella spiralis infected animals

  14. In-depth comparative analysis of malaria parasite genomes reveals protein-coding genes linked to human disease in Plasmodium falciparum genome.

    Science.gov (United States)

    Liu, Xuewu; Wang, Yuanyuan; Liang, Jiao; Wang, Luojun; Qin, Na; Zhao, Ya; Zhao, Gang

    2018-05-02

    genes highly transcribed at the trophozoite stage. Finally, 55 candidate genes were identified. Considering that parasite-infected erythrocyte surface protein 2 (PIESP2) contains gap-junction-related Neuromodulin_N domain and that anti-PIESP2 might provide protection against malaria, we chose PIESP2 for further experimental study. Our analysis revealed a limited number of genes linked to human disease in P. falciparum genome. These genes could be interesting targets for further functional characterization.

  15. Targeted mutagenesis in a human-parasitic nematode

    Science.gov (United States)

    Gang, Spencer S.; Castelletto, Michelle L.

    2017-01-01

    Parasitic nematodes infect over 1 billion people worldwide and cause some of the most common neglected tropical diseases. Despite their prevalence, our understanding of the biology of parasitic nematodes has been limited by the lack of tools for genetic intervention. In particular, it has not yet been possible to generate targeted gene disruptions and mutant phenotypes in any parasitic nematode. Here, we report the development of a method for introducing CRISPR-Cas9-mediated gene disruptions in the human-parasitic threadworm Strongyloides stercoralis. We disrupted the S. stercoralis twitchin gene unc-22, resulting in nematodes with severe motility defects. Ss-unc-22 mutations were resolved by homology-directed repair when a repair template was provided. Omission of a repair template resulted in deletions at the target locus. Ss-unc-22 mutations were heritable; we passed Ss-unc-22 mutants through a host and successfully recovered mutant progeny. Using a similar approach, we also disrupted the unc-22 gene of the rat-parasitic nematode Strongyloides ratti. Our results demonstrate the applicability of CRISPR-Cas9 to parasitic nematodes, and thereby enable future studies of gene function in these medically relevant but previously genetically intractable parasites. PMID:29016680

  16. Helminth parasites alter protection against Plasmodium infection.

    Science.gov (United States)

    Salazar-Castañon, Víctor H; Legorreta-Herrera, Martha; Rodriguez-Sosa, Miriam

    2014-01-01

    More than one-third of the world's population is infected with one or more helminthic parasites. Helminth infections are prevalent throughout tropical and subtropical regions where malaria pathogens are transmitted. Malaria is the most widespread and deadliest parasitic disease. The severity of the disease is strongly related to parasite density and the host's immune responses. Furthermore, coinfections between both parasites occur frequently. However, little is known regarding how concomitant infection with helminths and Plasmodium affects the host's immune response. Helminthic infections are frequently massive, chronic, and strong inductors of a Th2-type response. This implies that infection by such parasites could alter the host's susceptibility to subsequent infections by Plasmodium. There are a number of reports on the interactions between helminths and Plasmodium; in some, the burden of Plasmodium parasites increased, but others reported a reduction in the parasite. This review focuses on explaining many of these discrepancies regarding helminth-Plasmodium coinfections in terms of the effects that helminths have on the immune system. In particular, it focuses on helminth-induced immunosuppression and the effects of cytokines controlling polarization toward the Th1 or Th2 arms of the immune response.

  17. Mechanisms of cellular invasion by intracellular parasites.

    Science.gov (United States)

    Walker, Dawn M; Oghumu, Steve; Gupta, Gaurav; McGwire, Bradford S; Drew, Mark E; Satoskar, Abhay R

    2014-04-01

    Numerous disease-causing parasites must invade host cells in order to prosper. Collectively, such pathogens are responsible for a staggering amount of human sickness and death throughout the world. Leishmaniasis, Chagas disease, toxoplasmosis, and malaria are neglected diseases and therefore are linked to socio-economical and geographical factors, affecting well-over half the world's population. Such obligate intracellular parasites have co-evolved with humans to establish a complexity of specific molecular parasite-host cell interactions, forming the basis of the parasite's cellular tropism. They make use of such interactions to invade host cells as a means to migrate through various tissues, to evade the host immune system, and to undergo intracellular replication. These cellular migration and invasion events are absolutely essential for the completion of the lifecycles of these parasites and lead to their for disease pathogenesis. This review is an overview of the molecular mechanisms of protozoan parasite invasion of host cells and discussion of therapeutic strategies, which could be developed by targeting these invasion pathways. Specifically, we focus on four species of protozoan parasites Leishmania, Trypanosoma cruzi, Plasmodium, and Toxoplasma, which are responsible for significant morbidity and mortality.

  18. Conjugation of Inulin Improves Anti-Biofilm Activity of Chitosan.

    Science.gov (United States)

    Zhang, Guiqiang; Liu, Jing; Li, Ruilian; Jiao, Siming; Feng, Cui; Wang, Zhuo A; Du, Yuguang

    2018-05-04

    Bacteria biofilm helps bacteria prevent phagocytosis during infection and increase resistance to antibiotics. Staphylococcus aureus is a Gram-positive pathogenic bacterium and is tightly associated with biofilm-related infections, which have led to great threat to human health. Chitosan, the only cationic polysaccharide in nature, has been demonstrated to have antimicrobial and anti-biofilm activities, which, however, require a relative high dosage of chitosan. Moreover, poor water solubility further restricts its applications on anti-infection therapy. Inulins are a group of polysaccharides produced by many types of plants, and are widely used in processed foods. Compared to chitosan, inulin is very soluble in water and possesses a mild antibacterial activity against certain pathogenic bacteria. In order to develop an effective strategy to treat biofilm-related infections, we introduce a method by covalent conjugation of inulin to chitosan. The physicochemical characterization of the inulin⁻chitosan conjugate was assayed, and the anti-biofilm activity was evaluated against S. aureus biofilm. The results indicated that, as compared to chitosan, this novel polysaccharide⁻polysaccharide conjugate significantly enhanced activities against S. aureus either in a biofilm or planktonic state. Of note, the conjugate also showed a broad spectrum anti-biofilm activity on different bacteria strains and low cellular toxicity to mammalian cells. These results suggested that chitosan conjugation of inulin was a viable strategy for treatment against biofilm-related infections. This finding may further spread the application of natural polysaccharides on treatments of infectious disease.

  19. Biomechanical modelling and evaluation of construction jobs for performance improvement.

    Science.gov (United States)

    Parida, Ratri; Ray, Pradip Kumar

    2012-01-01

    Occupational risk factors, such as awkward posture, repetition, lack of rest, insufficient illumination and heavy workload related to construction-related MMH activities may cause musculoskeletal disorders and poor performance of the workers, ergonomic design of construction worksystems was a critical need for improving their health and safety wherein a dynamic biomechanical models were required to be empirically developed and tested at a construction site of Tata Steel, the largest steel making company of India in private sector. In this study, a comprehensive framework is proposed for biomechanical evaluation of shovelling and grinding under diverse work environments. The benefit of such an analysis lies in its usefulness in setting guidelines for designing such jobs with minimization of risks of musculoskeletal disorders (MSDs) and enhancing correct methods of carrying out the jobs leading to reduced fatigue and physical stress. Data based on direct observations and videography were collected for the shovellers and grinders over a number of workcycles. Compressive forces and moments for a number of segments and joints are computed with respect to joint flexion and extension. The results indicate that moments and compressive forces at L5/S1 link are significant for shovellers while moments at elbow and wrist are significant for grinders.

  20. Occurrence of Intestinal Parasitic Contamination in Select Consumed Local Raw Vegetables and Fruits in Kuantan, Pahang

    Science.gov (United States)

    Yusof, Afzan Mat; Mohammad, Mardhiah; Abdullahi, Muna Abshir; Mohamed, Zeehaida; Zakaria, Robaiza; Wahab, Ridhwan Abdul

    2017-01-01

    Intestinal parasitic infections are one of the most common causes of human diseases that result in serious health and economic issues in many developing and developed countries. Raw vegetables and fruits play an important role in transmitting parasites to humans. Hence, the aim of this study was to investigate the parasitological contamination of select commonly consumed local leafy vegetables and fruits in Kuantan, Malaysia. One kilogram of locally consumed raw vegetables and fruits were collected randomly from the Kuantan wet market (Pasar Tani) during the monsoon season (November 2014–January 2015) and the dry season (February 2015–April 2015). A standard wet mount procedure and modified Ziehl-Neelsen staining were used for the detection of parasites. In the present study, the examination of vegetables revealed five different parasite species. The vegetable samples collected from Kuantan’s wet market were positive for both helminthes and protozoa. However, the fruits samples were negative for parasitic contamination. Pegaga was the most contaminated leafy vegetable in this study, and Strongyloides was the parasite found most frequently. Furthermore, there was a high diversity in the type of parasites observed during the dry season compared to the monsoon season. Therefore, further action should be taken to reduce the occurrence of parasitic contamination in vegetables by implementing the principles of good agricultural practice and improving water treatment efficacy. PMID:28228914

  1. Predicting what helminth parasites a fish species should have using Parasite Co-occurrence Modeler (PaCo)

    Science.gov (United States)

    Strona, Giovanni; Lafferty, Kevin D.

    2013-01-01

    Fish pathologists are often interested in which parasites would likely be present in a particular host. Parasite Co-occurrence Modeler (PaCo) is a tool for identifying a list of parasites known from fish species that are similar ecologically, phylogenetically, and geographically to the host of interest. PaCo uses data from FishBase (maximum length, growth rate, life span, age at maturity, trophic level, phylogeny, and biogeography) to estimate compatibility between a target host and parasite species–genera from the major helminth groups (Acanthocephala, Cestoda, Monogenea, Nematoda, and Trematoda). Users can include any combination of host attributes in a model. These unique features make PaCo an innovative tool for addressing both theoretical and applied questions in parasitology. In addition to predicting the occurrence of parasites, PaCo can be used to investigate how host characteristics shape parasite communities. To test the performance of the PaCo algorithm, we created 12,400 parasite lists by applying any possible combination of model parameters (248) to 50 fish hosts. We then measured the relative importance of each parameter by assessing their frequency in the best models for each host. Host phylogeny and host geography were identified as the most important factors, with both present in 88% of the best models. Habitat (64%) was identified in more than half of the best models. Among ecological parameters, trophic level (41%) was the most relevant while life span (34%), growth rate (32%), maximum length (28%), and age at maturity (20%) were less commonly linked to best models. PaCo is free to use at www.purl.oclc.org/fishpest.

  2. Effect of age, photoperiod and host availability on the parasitism behavior of Oomyzus sokolowskii Kurdjumov (Hymenoptera: Eulophidae)

    International Nuclear Information System (INIS)

    Silva-Torres, Christian S.A.; Barros, Reginaldo; Torres, Jorge B.

    2009-01-01

    The high reproduction rate, potential to cause damage, wide geographic distribution and resistance to insecticides of Plutella xylostella (L.) makes difficult its efficient control. However, larvae and pupae of this pest are naturally parasitized by Oomyzus Sokolowskii (Kurdjumov), providing opportunities to improve the natural parasitism. This study investigated the effects of the age of adult parasitoids, host availability and time of exposure on O. sokolowskii parasitism behavior. The number of larvae encounters by parasitoid females and the parasitism rate increased with parasitoid age up to 96 h. The parasitization was higher when wasps received a constant number of hosts daily in comparison with a random number (13.3 versus 8.9 larvae parasitized). Female parasitization activity was maintained up to the age of 20 days in both treatments and exhibited similar longevity (constant host = 33.5 d; and random host = 34.7 d). The progeny produced per female and the number of parasitoids emerged per host significantly decreased as wasps aged. There was no significant effect of the light regime (12 h darkness or 12 h light exposure) on the parasitization, although parasitoid was more active after 3 h of light exposure. Therefore, further studies on field application of O. sokolowskii should consider the release of 48 h - to 72 h - old parasitoids at dawn as a way to increase the success of host parasitization. (author)

  3. Sex as a strategy against rapidly evolving parasites.

    Science.gov (United States)

    Auld, Stuart K J R; Tinkler, Shona K; Tinsley, Matthew C

    2016-12-28

    Why is sex ubiquitous when asexual reproduction is much less costly? Sex disrupts coadapted gene complexes; it also causes costs associated with mate finding and the production of males who do not themselves bear offspring. Theory predicts parasites select for host sex, because genetically variable offspring can escape infection from parasites adapted to infect the previous generations. We examine this using a facultative sexual crustacean, Daphnia magna, and its sterilizing bacterial parasite, Pasteuria ramosa We obtained sexually and asexually produced offspring from wild-caught hosts and exposed them to contemporary parasites or parasites isolated from the same population one year later. We found rapid parasite adaptation to replicate within asexual but not sexual offspring. Moreover, sexually produced offspring were twice as resistant to infection as asexuals when exposed to parasites that had coevolved alongside their parents (i.e. the year two parasite). This fulfils the requirement that the benefits of sex must be both large and rapid for sex to be favoured by selection. © 2016 The Author(s).

  4. Screening of chemical compound libraries identified new anti-Toxoplasma gondii agents.

    Science.gov (United States)

    Adeyemi, Oluyomi Stephen; Sugi, Tatsuki; Han, Yongmei; Kato, Kentaro

    2018-02-01

    Toxoplasma gondii is the etiological agent of toxoplasmosis, a common parasitic disease that affects nearly one-third of the human population. The primary infection can be asymptomatic in healthy individuals but may prove fatal in immunocompromised individuals. Available treatment options for toxoplasmosis patients are limited, underscoring the urgent need to identify and develop new therapies. Non-biased screening of libraries of chemical compounds including the repurposing of well-characterized compounds is emerging as viable approach to achieving this goal. In the present investigation, we screened libraries of natural product and FDA-approved compounds to identify those that inhibited T. gondii growth. We identified 32 new compounds that potently inhibit T. gondii growth. Our findings are new and promising, and further strengthen the prospects of drug repurposing as well as the screening of a wide range of chemical compounds as a viable source of alternative anti-parasitic therapeutic agents.

  5. Prevalence of Intestinal Parasitic Infections Among Primary School Children in Bushehr, Iran

    Directory of Open Access Journals (Sweden)

    Barazesh

    2016-08-01

    Full Text Available Background Due to their weak immune systems, contact with soil, and failure to comply with hygiene principles, the prevalence of intestinal parasitic infection is high among children. Objectives This study was conducted to determine the prevalence of intestinal parasitic infection and the effects of various factors among elementary school children in Bushehr, Iran. Methods Following coordination with the education office, schools were randomly selected from different areas, and fecal samples were collected from 203 males and females students at different education levels. The samples were examined using the formalin-ether sedimentation technique. The data were collected via questionnaires and analyzed using SPSS 18.0 and the Chi-squared test. Results Approximately 25.1% of the children were infected with at least one type of intestinal parasite, and 5.9% of them were infected with more than one species. The highest prevalence was apparent in children at education levels 4 and 5. There was no significant relationship between infection and parents’ education and some clinical symptoms, such as abdominal pain, loss of appetite, and nausea, but there was a significant relationship with the number of family members. Conclusions The prevalence of intestinal parasitic infections was relatively high among the schoolchildren in this study. Since these parasites can cause anemia and dysfunctional nutrient absorption, growth, and learning among children, it is suggested that training courses be held for parents and that basic steps be taken to improve the level of hygiene in the region to prevent the transmission of these parasites.

  6. Structural considerations for functional anti-EGFR × anti-CD3 bispecific diabodies in light of domain order and binding affinity.

    Science.gov (United States)

    Asano, Ryutaro; Nagai, Keisuke; Makabe, Koki; Takahashi, Kento; Kumagai, Takashi; Kawaguchi, Hiroko; Ogata, Hiromi; Arai, Kyoko; Umetsu, Mitsuo; Kumagai, Izumi

    2018-03-02

    We previously reported a functional humanized bispecific diabody (bsDb) that targeted EGFR and CD3 (hEx3-Db) and enhancement of its cytotoxicity by rearranging the domain order in the V domain. Here, we further dissected the effect of domain order in bsDbs on their cross-linking ability and binding kinetics to elucidate general rules regarding the design of functional bsDbs. Using Ex3-Db as a model system, we first classified the four possible domain orders as anti-parallel (where both chimeric single-chain components are variable heavy domain (VH)-variable light domain (VL) or VL-VH order) and parallel types (both chimeric single-chain components are mixed with VH-VL and VL-VH order). Although anti-parallel Ex3-Dbs could cross-link the soluble target antigens, their cross-linking ability between soluble targets had no correlation with their growth inhibitory effects. In contrast, the binding affinity of one of the two constructs with a parallel-arrangement V domain was particularly low, and structural modeling supported this phenomenon. Similar results were observed with E2x3-Dbs, in which the V region of the anti-EGFR antibody clone in hEx3 was replaced with that of another anti-EGFR clone. Only anti-parallel types showed affinity-dependent cancer inhibitory effects in each molecule, and E2x3-LH (both components in VL-VH order) showed the most intense anti-tumor activity in vitro and in vivo . Our results showed that, in addition to rearranging the domain order of bsDbs, increasing their binding affinity may be an ideal strategy for enhancing the cytotoxicity of anti-parallel constructs and that E2x3-LH is particularly attractive as a candidate next-generation anti-cancer drug.

  7. From Fossil Parasitoids to Vectors: Insects as Parasites and Hosts.

    Science.gov (United States)

    Nagler, Christina; Haug, Joachim T

    2015-01-01

    Within Metazoa, it has been proposed that as many as two-thirds of all species are parasitic. This propensity towards parasitism is also reflected within insects, where several lineages independently evolved a parasitic lifestyle. Parasitic behaviour ranges from parasitic habits in the strict sense, but also includes parasitoid, phoretic or kleptoparasitic behaviour. Numerous insects are also the host for other parasitic insects or metazoans. Insects can also serve as vectors for numerous metazoan, protistan, bacterial and viral diseases. The fossil record can report this behaviour with direct (parasite associated with its host) or indirect evidence (insect with parasitic larva, isolated parasitic insect, pathological changes of host). The high abundance of parasitism in the fossil record of insects can reveal important aspects of parasitic lifestyles in various evolutionary lineages. For a comprehensive view on fossil parasitic insects, we discuss here different aspects, including phylogenetic systematics, functional morphology and a direct comparison of fossil and extant species. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Pathoecology of Chiribaya parasitism

    Directory of Open Access Journals (Sweden)

    Martinson Elizabeth

    2003-01-01

    Full Text Available The excavations of Chiribaya culture sites in the Osmore drainage of southern Peru focused on the recovery of information about prehistoric disease, including parasitism. The archaeologists excavated human, dog, guinea pig, and llama mummies. These mummies were analyzed for internal and external parasites. The results of the analysis and reconstruction of prehistoric life from the excavations allows us to interpret the pathoecology of the Chiribaya culture.

  9. Parasites and parasite management practices of organic and conventional dairy herds in Minnesota.

    Science.gov (United States)

    Sorge, U S; Moon, R D; Stromberg, B E; Schroth, S L; Michels, L; Wolff, L J; Kelton, D F; Heins, B J

    2015-05-01

    The objective of this study was to describe the prevalence and practices used to manage internal helminth parasites and external arthropod parasites on organic and conventional dairy herds in Minnesota. All organic (ORG) dairy herds in Minnesota (n=114) and a convenience sample of conventional herds were invited to participate in the study. Thirty-five ORG herds and 28 conventional herds were visited once in summer and fall of 2012. Conventional dairy herds were split into small conventional (SC,conventional herds (MC, ≥200 cows) so that SC herds were comparable in size to the ORG herds. Dairy managers were surveyed to assess their farm management practices and perceptions about parasites, hygiene scores were recorded for adult stock, and fecal samples were collected from a nominal 20 breeding-age heifers to characterize abundance of internal parasites. Nonparametric tests were used to compare fecal egg counts per gram (FEC) among farms grouped by management systems and practices. Organic farms had more designated pasture and were more likely to use rotational grazing compared with conventional farms, but the stocking densities of animals on pasture were similar among farm types. The overall FEC were very low, and only a few individual ORG heifers had FEC >500 eggs/gram. Samples from heifers on ORG farms had significantly more strongyle-type eggs than those on SC and MC farms (ORG: 6.6±2.1; SC: 0.5±0.3; MC: 0.8±0.7), but egg counts of other types of gastrointestinal parasites did not differ significantly among the 3 herd groups. Fly control measures were applied mainly to milking cows and preweaned calves and were used on 88.6% of ORG herds, 60.0% of SC herds, and 91.7% of MC herds. Approximately half of the producers reported having seen skin conditions suggestive of lice or tail mange in their cattle during the previous winter (ORG: 48.6%, SC: 57.1%, MC: 53.9%). Although most conventional producers reported treating these skin conditions, most organic

  10. Measurement of b anti b correlations at the CERN p anti p collider

    International Nuclear Information System (INIS)

    Albajar, C.; Ankoviak, K.; Bartha, S.; Bezaguet, A.; Boehrer, A.; Bos, K.; Buchanan, C.; Buschbeck, B.; Castilla-Valdez, H.; Cennini, P.; Cittolin, S.; Clayton, E.; Cline, D.; Caughlan, J.A.; Dau, D.; Daum, C.; Della Negra, M.; Demoulin, M.; Denegri, D.; Dibon, H.; Dorenbosch, J.; Dowell, J.D.; Eggert, K.; Eisenhandler, E.; Ellis, N.; Evans, H.; Faissner, H.; Fensome, I.F.; Fortson, L.; Garvey, J.; Geiser, A. Givernaud, A.; Gonidec, A.; Gonzalez, B.; Gronberg, J.; Holthuizen, D.J.; Jank, W.; Jorat, G.; Kalmus, P.I.P.; Karimaeki, V.; Kenyon, I.; Kinnunen, R.; Krammer, M.; Lammel, S.; Landon, M.P.J.; Lemoigne, Y.; Levegruen, S.; Lipa, P.; Markou, C.; Markytan, M.; Maurin, G.; McMahon, S.; Merlo, J.P.; Meyer, T.; Moers, T.; Mohammadi, M.; Morsch, A.; Moulin, A.; Norton, A.; Otwinowski, S.; Pancheri, G.; Pietarinen, E.; Pimiae, M.; Placci, A.; Porte, J.P.; Priem, R.; Prosi, R.; Radermacher, E.; Rauschkolb, M.; Reithler, H.; Revol, J.P.; Robinson, D.; Rubbia, C.; Samyn, D.; Schinzel, D.; Schleichert, R.; Schroeder, M.; Seez, C.; Shah, T.P.; Sphicas, P.; Sumorok, K.; Szoncso, F.; Tan, C.H.; Taurok, A.; Taylor, L.; Tether, S.; Teykal, H.; Thompson, G.; Tuchscherer, H.; Tuominiemi, J.; Van de Guchte, W.; Van Dijk, A.; Vargas, M.; Virdee, T.S.; Schlippe, W. von; Vuillemin, V.; Wacker, K.; Wagner, H.; Walzel, G.; Wulz, C.E.; Zotto, P.; NIKHEF-H, Amsterdam; Birmingham Univ.; CERN, Geneva; Helsinki Univ.; Kiel Univ.; Blackett Lab., Imperial Coll., London; Queen Mary and Westfield Coll., London; MIT, Cambridge, MA; Rutherford Appleton Lab., Chilton; DPHPE/SEPh, CEN Saclay, Gif-sur-Yvette; California Univ., Los Angeles, CA; Oesterreichische Akademie der Wissenschaften, Vienna

    1994-01-01

    We report on measurements of correlated b anti b production in p anti p at √s=630 GeV, using dimuon data to tag both the b and anti b quarks. Starting from an inclusive dimuon sample we obtain improved cross-sections for single inclusive beauty production and confirm our earlier results on B 0 - anti B 0 mixing. From a study of b anti b correlations we derive explicit cross-sections for semi-differential b anti b production. We compare the measured cross-sections and correlations to OMIKRON (α s 3 ) QCD predictions and find good quantitative agreement. From the measured angular distributions we establish a sizeable contribution from higher order QCD processes with a significance of about seven standard deviations. A large nonperturbative contribution to these higher order corrections is excluded. (orig.)

  11. Trypanosoma cruzi Evades the Complement System as an Efficient Strategy to Survive in the Mammalian Host: The Specific Roles of Host/Parasite Molecules and Trypanosoma cruzi Calreticulin

    Directory of Open Access Journals (Sweden)

    Galia Ramírez-Toloza

    2017-09-01

    interplay. Thus, we have proposed that TcCRT is a pleiotropic molecule, present not only in the parasite endoplasmic reticulum, but also on the trypomastigote surface, participating in key processes to establish T. cruzi infection, such as inhibition of the complement system and serving as an important virulence factor. Additionally, TcCRT interaction with key complement components, participates as an anti-angiogenic and anti-tumor molecule, inhibiting at least in important part, tumor growth in infected animals.

  12. Large-scale fabrication of superhydrophobic polyurethane/nano-Al2O3 coatings by suspension flame spraying for anti-corrosion applications

    Science.gov (United States)

    Chen, Xiuyong; Yuan, Jianhui; Huang, Jing; Ren, Kun; Liu, Yi; Lu, Shaoyang; Li, Hua

    2014-08-01

    This study aims to further enhance the anti-corrosion performances of Al coatings by constructing superhydrophobic surfaces. The Al coatings were initially arc-sprayed onto steel substrates, followed by deposition of polyurethane (PU)/nano-Al2O3 composites by a suspension flame spraying process. Large-scale corrosion-resistant superhydrophobic PU/nano-Al2O3-Al coatings were successfully fabricated. The coatings showed tunable superhydrophilicity/superhydrophobicity as achieved by changing the concentration of PU in the starting suspension. The layer containing 2.0 wt.%PU displayed excellent hydrophobicity with the contact angle of ∼151° and the sliding angle of ∼6.5° for water droplets. The constructed superhydrophobic coatings showed markedly improved anti-corrosion performances as assessed by electrochemical corrosion testing carried out in 3.5 wt.% NaCl solution. The PU/nano-Al2O3-Al coatings with superhydrophobicity and competitive anti-corrosion performances could be potentially used as protective layers for marine infrastructures. This study presents a promising approach for fabricatiing superhydrophobic coatings for corrosion-resistant applications.

  13. Quantitative Analysis of a Parasitic Antiviral Strategy

    OpenAIRE

    Kim, Hwijin; Yin, John

    2004-01-01

    We extended a computer simulation of viral intracellular growth to study a parasitic antiviral strategy that diverts the viral replicase toward parasite growth. This strategy inhibited virus growth over a wide range of conditions, while minimizing host cell perturbations. Such parasitic strategies may inhibit the development of drug-resistant virus strains.

  14. Spread of anti-malarial drug resistance: Mathematical model with implications for ACT drug policies

    Directory of Open Access Journals (Sweden)

    Dondorp Arjen M

    2008-11-01

    Full Text Available Abstract Background Most malaria-endemic countries are implementing a change in anti-malarial drug policy to artemisinin-based combination therapy (ACT. The impact of different drug choices and implementation strategies is uncertain. Data from many epidemiological studies in different levels of malaria endemicity and in areas with the highest prevalence of drug resistance like borders of Thailand are certainly valuable. Formulating an appropriate dynamic data-driven model is a powerful predictive tool for exploring the impact of these strategies quantitatively. Methods A comprehensive model was constructed incorporating important epidemiological and biological factors of human, mosquito, parasite and treatment. The iterative process of developing the model, identifying data needed, and parameterization has been taken to strongly link the model to the empirical evidence. The model provides quantitative measures of outcomes, such as malaria prevalence/incidence and treatment failure, and illustrates the spread of resistance in low and high transmission settings. The model was used to evaluate different anti-malarial policy options focusing on ACT deployment. Results The model predicts robustly that in low transmission settings drug resistance spreads faster than in high transmission settings, and treatment failure is the main force driving the spread of drug resistance. In low transmission settings, ACT slows the spread of drug resistance to a partner drug, especially at high coverage rates. This effect decreases exponentially with increasing delay in deploying the ACT and decreasing rates of coverage. In the high transmission settings, however, drug resistance is driven by the proportion of the human population with a residual drug level, which gives resistant parasites some survival advantage. The spread of drug resistance could be slowed down by controlling presumptive drug use and avoiding the use of combination therapies containing drugs with

  15. Construction of transmission pipeline across Osaka bay area -pipeline construction by shield tunnel under seabed-; Construction d'un gazoduc dans la zone de la baie d'Osaka - tunnel de protection sous-marin

    Energy Technology Data Exchange (ETDEWEB)

    Takashi, AIhara [Osaka Gas Co., Ltd (Japan)

    2000-07-01

    Osaka Gas has been constructing a transmission gas pipeline across Osaka Bay Area with Osaka Port that has busy traffic. The company met several technical problems on the construction-design with measures against the subsidence of reclaimed land, anti-seismic measures, for example, in designing the pipeline construction by shield tunnel under seabed. This paper introduces the solutions to the technical problems. (authors)

  16. Using a One Health approach to assess the impact of parasitic disease in livestock: how does it add value?

    Science.gov (United States)

    Rushton, Jonathan; Bruce, Mieghan

    2017-01-01

    Human population increases, with greater food demands, have resulted in a rapid evolution of livestock food systems, leading to changes in land and water use. The scale of global livestock systems mean that changes in animal health status, particularly in parasite levels, have impacts that go beyond farm and sector levels. To quantify the true impact of parasites in livestock, frameworks that look at both resources and services valued in markets and those that have no true market value are required. Mitigating the effects of parasitic disease in livestock will not only increase productivity, but also improve animal welfare and human health, whilst reducing the environmental burden of livestock production systems. To measure these potential benefits, a One Health approach is needed. This paper discusses the types of methods and the data collection tools needed for a more holistic perspective and provides a framework with its application to coccidiosis in poultry. To build a body of knowledge that allows the ranking of parasite diseases in a wider animal health setting, such One Health frameworks need to be applied more frequently and with rigour. The outcome will improve the allocation of resources to critical constraints on parasite management.

  17. Animal health and greenhouse gas intensity: the paradox of periparturient parasitism.

    Science.gov (United States)

    Houdijk, J G M; Tolkamp, B J; Rooke, J A; Hutchings, M R

    2017-09-01

    Here we provide the first known direct measurements of pathogen challenge impacts on greenhouse gas production, yield and intensity. Twin-rearing ewes were ad libitum fed pelleted lucerne from day -32 to 36 (day 0 is parturition), and repeatedly infected with 10,000 Teladorsagia circumcincta infective larvae (n=16), or sham-dosed with water (n=16). A third group of 16 ewes were fed at 80% of uninfected ewes' feed intake during lactation. Methane emissions were measured in respiration chambers (day 30-36) whilst total tract apparent nutrient digestibility around day 28 informed calculated manure methane and nitrous oxide emissions estimates. Periparturient parasitism reduced feed intake (-9%) and litter weight gain (-7%) and doubled maternal body weight loss. Parasitism reduced daily enteric methane production by 10%, did not affect the methane yield per unit of dry matter intake but increased the yield per unit of digestible organic matter intake by 14%. Parasitism did not affect the daily calculated manure methane and nitrous oxide production, but increased the manure methane and nitrous oxide yields per unit of dry matter intake by 16% and 4%, respectively, and per unit of digestible organic matter intake by 46% and 31%, respectively. Accounting for increased lucerne input for delayed weaning and maternal body weight loss compensation, parasitism increased the calculated greenhouse gas intensity per kg of lamb weight gain for enteric methane (+11%), manure methane (+32%) and nitrous oxide (+30%). Supplemented with the global warming potential associated with production of pelleted lucerne, we demonstrated that parasitism increased calculated global warming potential per kg of lamb weight gain by 16%, which was similar to the measured impact of parasitism on the feed conversion ratio. Thus, arising from a pathogen-induced feed efficiency reduction and modified greenhouse gas emissions, we demonstrated that ovine periparturient parasitism increases greenhouse gas

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

    Science.gov (United States)

    Van den Broeck, Frederik; Maes, Gregory E.; Larmuseau, Maarten H. D.; Rollinson, David; Sy, Ibrahima; Faye, Djibril; Volckaert, Filip A. M.; Polman, Katja; Huyse, Tine

    2015-01-01

    Background Anthropogenic environmental changes may lead to ecosystem destabilization and the unintentional colonization of new habitats by parasite populations. A remarkable example is the outbreak of intestinal schistosomiasis in Northwest Senegal following the construction of two dams in the ‘80s. While many studies have investigated the epidemiological, immunological and geographical patterns of Schistosoma mansoni infections in this region, little is known about its colonization history. Methodology/Principal Findings Parasites were collected at several time points after the disease outbreak and genotyped using a 420 bp fragment of the mitochondrial cytochrome c oxidase subunit 1 gene (cox1) and nine nuclear DNA microsatellite markers. Phylogeographic and population genetic analyses revealed the presence of (i) many genetically different haplotypes at the non-recombining mitochondrial marker and (ii) one homogenous S. mansoni genetic group at the recombining microsatellite markers. These results suggest that the S. mansoni population in Northwest Senegal was triggered by intraspecific hybridization (i.e. admixture) between parasites that were introduced from different regions. This would comply with the extensive immigration of infected seasonal agricultural workers from neighboring regions in Senegal, Mauritania and Mali. The spatial and temporal stability of the established S. mansoni population suggests a swift local adaptation of the parasite to the local intermediate snail host Biomphalaria pfeifferi at the onset of the epidemic. Conclusions/Significance Our results show that S. mansoni parasites are very successful in colonizing new areas without significant loss of genetic diversity. Maintaining high levels of diversity guarantees the adaptive potential of these parasites to cope with selective pressures such as drug treatment, which might complicate efforts to control the disease. PMID:26275049

  19. Evaluation of the Anti-schistosomal Effects of Turmeric (Curcuma longa) Versus Praziquantel in Schistosoma mansoni Infected Mice.

    Science.gov (United States)

    Hussein, Atef; Rashed, Samia; El Hayawan, Ibrahim; El-Sayed, Rabab; Ali, Hemat

    2017-01-01

    Curcumin is the major active ingredient of Curcuma longa L. , traditionally known as turmeric and has been shown to exhibit a wide range of pharmacological activities including anti-parasitic effect. However, it is found to be water-insoluble and has low bioavailability. The aim of this study was to explore the potential role of turmeric solved in olive oil either alone or in combination with praziquantel (PZQ) in treatment of schistosomiasis mansoni . The whole turmeric powder suspended in olive oil (as a solvent) is indicated to S. mansoni -infected mice aiming to study its potential therapeutic role, either alone or in combination with PZQ. Turmeric significantly reduced S. mansoni worm burden and complete absence of adult worms achieved in mice treated with combination of turmeric and PZQ. Turmeric has slight non-significant effect on the oogram pattern in all examined S. mansoni infected mice. Turmeric and PZQ found to exert a significant reduction of granuloma size in comparison with control. However, turmeric has a non-significant effect on granuloma number. On the other hand, turmeric or/and PZQ treated mice showed obvious improvement of pathology with mild cloudy swelling and less hydropic degeneration. Turmeric significantly reduced parasite worm burden, granuloma size and consequently the pathology of affected liver, it still far less effective than PZQ.

  20. Disentangling the influence of parasite genotype, host genotype and maternal environment on different stages of bacterial infection in Daphnia magna.

    Science.gov (United States)

    Hall, Matthew D; Ebert, Dieter

    2012-08-22

    Individuals naturally vary in the severity of infectious disease when exposed to a parasite. Dissecting this variation into genetic and environmental components can reveal whether or not this variation depends on the host genotype, parasite genotype or a range of environmental conditions. Complicating this task, however, is that the symptoms of disease result from the combined effect of a series of events, from the initial encounter between a host and parasite, through to the activation of the host immune system and the exploitation of host resources. Here, we use the crustacean Daphnia magna and its parasite Pasteuria ramosa to show how disentangling genetic and environmental factors at different stages of infection improves our understanding of the processes shaping infectious disease. Using compatible host-parasite combinations, we experimentally exclude variation in the ability of a parasite to penetrate the host, from measures of parasite clearance, the reduction in host fecundity and the proliferation of the parasite. We show how parasite resistance consists of two components that vary in environmental sensitivity, how the maternal environment influences all measured aspects of the within-host infection process and how host-parasite interactions following the penetration of the parasite into the host have a distinct temporal component.