WorldWideScience

Sample records for lethal parasite challenge

  1. Experimental evaluation of the relationship between lethal or non-lethal virulence and transmission success in malaria parasite infections

    Directory of Open Access Journals (Sweden)

    Nithiuthai S

    2004-09-01

    Full Text Available Abstract Background Evolutionary theory suggests that the selection pressure on parasites to maximize their transmission determines their optimal host exploitation strategies and thus their virulence. Establishing the adaptive basis to parasite life history traits has important consequences for predicting parasite responses to public health interventions. In this study we examine the extent to which malaria parasites conform to the predicted adaptive trade-off between transmission and virulence, as defined by mortality. The majority of natural infections, however, result in sub-lethal virulent effects (e.g. anaemia and are often composed of many strains. Both sub-lethal effects and pathogen population structure have been theoretically shown to have important consequences for virulence evolution. Thus, we additionally examine the relationship between anaemia and transmission in single and mixed clone infections. Results Whereas there was a trade-off between transmission success and virulence as defined by host mortality, contradictory clone-specific patterns occurred when defining virulence by anaemia. A negative relationship between anaemia and transmission success was found for one of the parasite clones, whereas there was no relationship for the other. Notably the two parasite clones also differed in a transmission phenotype (gametocyte sex ratio that has previously been shown to respond adaptively to a changing blood environment. In addition, as predicted by evolutionary theory, mixed infections resulted in increased anaemia. The increased anaemia was, however, not correlated with any discernable parasite trait (e.g. parasite density or with increased transmission. Conclusions We found some evidence supporting the hypothesis that there is an adaptive basis correlating virulence (as defined by host mortality and transmission success in malaria parasites. This confirms the validity of applying evolutionary virulence theory to biomedical

  2. Novel neutralizing monoclonal antibodies protect rodents against lethal filovirus challenges

    Directory of Open Access Journals (Sweden)

    Caleb D. Marceau

    2014-01-01

    Full Text Available Filoviruses are the causative agents of lethal hemorrhagic fever in human and non-human primates (NHP. The family of Filoviridae is composed of three genera, Ebolavirus, Marburgvirus and Cuevavirus. There are currently no approved vaccines or antiviral therapeutics for the treatment of filovirus infections in humans. Passive transfer of neutralizing antibodies targeting the Ebola virus (EBOV glycoprotein (GP has proven effective in protecting mice, guinea pigs and NHP from lethal challenges with EBOV. In this study, we generated two neutralizing monoclonal antibodies (MAbs, termed S9 and M4 that recognize the GP of EBOV or multiple strains of Marburg virus (MARV, respectively. We characterized the putative binding site of S9 as a linear epitope on the glycan cap of the GP1 subunit of the EBOV-GP. The M4 antibody recognizes an unknown conformational epitope on MARV-GP. Additionally, we demonstrated the post-exposure protection potential of these antibodies in both the mouse and guinea pig models of filovirus infection. These data indicate that MAbs S9 and M4 would be good candidates for inclusion in an antibody cocktail for the treatment of filovirus infections.

  3. Parasitic infections in HIV infected individuals: Diagnostic & therapeutic challenges

    Science.gov (United States)

    Nissapatorn, Veeranoot; Sawangjaroen, Nongyao

    2011-01-01

    After 30 years of the human immunodeficiency virus (HIV) epidemic, parasites have been one of the most common opportunistic infections (OIs) and one of the most frequent causes of morbidity and mortality associated with HIV-infected patients. Due to severe immunosuppression, enteric parasitic pathogens in general are emerging and are OIs capable of causing diarrhoeal disease associated with HIV. Of these, Cryptosporidium parvum and Isospora belli are the two most common intestinal protozoan parasites and pose a public health problem in acquired immunodeficiency syndrome (AIDS) patients. These are the only two enteric protozoan parasites that remain in the case definition of AIDS till today. Leismaniasis, strongyloidiasis and toxoplasmosis are the three main opportunistic causes of systemic involvements reported in HIV-infected patients. Of these, toxoplasmosis is the most important parasitic infection associated with the central nervous system. Due to its complexity in nature, toxoplasmosis is the only parasitic disease capable of not only causing focal but also disseminated forms and it has been included in AIDS-defining illnesses (ADI) ever since. With the introduction of highly active anti-retroviral therapy (HAART), cryptosporidiosis, leishmaniasis, schistosomiasis, strongyloidiasis, and toxoplasmosis are among parasitic diseases reported in association with immune reconstitution inflammatory syndrome (IRIS). This review addresses various aspects of parasitic infections in term of clinical, diagnostic and therapeutic challenges associated with HIV-infection. PMID:22310820

  4. Making sense of genomes of parasitic worms: Tackling bioinformatic challenges.

    Science.gov (United States)

    Korhonen, Pasi K; Young, Neil D; Gasser, Robin B

    2016-01-01

    Billions of people and animals are infected with parasitic worms (helminths). Many of these worms cause diseases that have a major socioeconomic impact worldwide, and are challenging to control because existing treatment methods are often inadequate. There is, therefore, a need to work toward developing new intervention methods, built on a sound understanding of parasitic worms at molecular level, the relationships that they have with their animal hosts and/or the diseases that they cause. Decoding the genomes and transcriptomes of these parasites brings us a step closer to this goal. The key focus of this article is to critically review and discuss bioinformatic tools used for the assembly and annotation of these genomes and transcriptomes, as well as various post-genomic analyses of transcription profiles, biological pathways, synteny, phylogeny, biogeography and the prediction and prioritisation of drug target candidates. Bioinformatic pipelines implemented and established recently provide practical and efficient tools for the assembly and annotation of genomes of parasitic worms, and will be applicable to a wide range of other parasites and eukaryotic organisms. Future research will need to assess the utility of long-read sequence data sets for enhanced genomic assemblies, and develop improved algorithms for gene prediction and post-genomic analyses, to enable comprehensive systems biology explorations of parasitic organisms.

  5. Infection-Mediated Priming of Phagocytes Protects against Lethal Secondary Aspergillus fumigatus Challenge

    Science.gov (United States)

    Savers, Amélie; Rasid, Orhan; Parlato, Marianna; Brock, Matthias; Jouvion, Gregory; Ryffel, Bernhard; Cavaillon, Jean-Marc; Eberl, Gerard; Ibrahim-Granet, Oumaïma

    2016-01-01

    Phagocytes restrict the germination of Aspergillus fumigatus conidia and prevent the establishment of invasive pulmonary aspergillosis in immunecompetent mice. Here we report that immunecompetent mice recovering from a primary A. fumigatus challenge are protected against a secondary lethal challenge. Using RAGγc knock-out mice we show that this protection is independent of T, B and NK cells. In protected mice, lung phagocytes are recruited more rapidly and are more efficient in conidial phagocytosis and killing. Protection was also associated with an enhanced expression of CXCR2 and Dectin-1 on bone marrow phagocytes. We also show that protective lung cytokine and chemokine responses are induced more rapidly and with enhanced dynamics in protected mice. Our findings support the hypothesis that following a first encounter with a non-lethal dose of A. fumigatus conidia, the innate immune system is primed and can mediate protection against a secondary lethal infection. PMID:27078879

  6. The bureaucratization of war: moral challenges exemplified by the covert lethal drone

    Directory of Open Access Journals (Sweden)

    Richard Adams

    2013-12-01

    Full Text Available This article interrogates the bureaucratization of war, incarnate in the covert lethal drone. Bureaucracies are criticized typically for their complexity, inefficiency, and inflexibility. This article is concerned with their moral indifference. It explores killing, which is so highly administered, so morally remote, and of such scale, that we acknowledge a covert lethal program. This is a bureaucratized program of assassination in contravention of critical human rights. In this article, this program is seen to compromise the advance of global justice. Moreover, the bureaucratization of lethal force is seen to dissolve democratic ideals from within. The bureaucracy isolates the citizens from lethal force applied in their name. People are killed, in the name of the State, but without conspicuous justification, or judicial review, and without informed public debate. This article gives an account of the risk associated with the bureaucratization of the State's lethal power. Exemplified by the covert drone, this is power with formidable reach. It is power as well, which requires great moral sensitivity. Considering the drone program, this article identifies challenges, which will become more prominent and pressing, as technology advances.

  7. DNA Vaccines against Protozoan Parasites: Advances and Challenges

    Directory of Open Access Journals (Sweden)

    Eric Dumonteil

    2007-01-01

    Full Text Available Over the past 15 years, DNA vaccines have gone from a scientific curiosity to one of the most dynamic research field and may offer new alternatives for the control of parasitic diseases such as leishmaniasis and Chagas disease. We review here some of the advances and challenges for the development of DNA vaccines against these diseases. Many studies have validated the concept of using DNA vaccines for both protection and therapy against these protozoan parasites in a variety of mouse models. The challenge now is to translate what has been achieved in these models into veterinary or human vaccines of comparable efficacy. Also, genome-mining and new antigen discovery strategies may provide new tools for a more rational search of novel vaccine candidates.

  8. Dendritic Cell Targeting of Bacillus anthracis Protective Antigen Expressed by Lactobacillus acidophilus Protects Mice from Lethal Challenge

    Science.gov (United States)

    2008-10-28

    Dendritic cell targeting of Bacillus anthracis protective antigen expressed by Lactobacillus acidophilus protects mice from lethal challenge M...lethal chal- lenge. A vaccine strategy was established by using Lactobacillus acidophilus to deliver Bacillus anthracis protective antigen (PA) via...include species of Lactobacillus , Lactococcus, Leuconostoc, Pedio- coccus, and Streptococcus. It is widely accepted that Lactobacillus species play a

  9. Galantamine is a novel post-exposure therapeutic against lethal VX challenge.

    Science.gov (United States)

    Hilmas, Corey J; Poole, Melissa J; Finneran, Kathryn; Clark, Matthew G; Williams, Patrick T

    2009-10-15

    The ability of galantamine hydrobromide (GAL HBr) treatment to antagonize O-ethyl-S-(2-diisopropylaminoethyl) methylphosphonothiolate (VX)-induced lethality, impairment of muscle tension, and electroencephalographic (EEG) changes was assessed in guinea pigs. Guinea pigs were challenged with 16.8 microg/kg VX (2LD50). One min after challenge, animals were administered 0.5 mg/kg atropine sulfate (ATR) and 25 mg/kg pyridine-2-aldoxime methochloride (2-PAM). In addition, guinea pigs were given 0, 1, 2, 4, 8 or 10 mg/kg GAL as a post-exposure treatment immediately prior to ATR and 2-PAM. Animals were either monitored for 24-h survival, scheduled for electroencephalography (EEG) recording, or euthanized 60 min later for measurement of indirectly-elicited muscle tension in the hemidiaphragm. Post-exposure GAL therapy produced a dose-dependent increase in survival from lethal VX challenge. Optimal clinical benefits were observed in the presence of 10 mg/kg GAL, which led to 100% survival of VX-challenged guinea pigs. Based on muscle physiology studies, GAL post-exposure treatment protected the guinea pig diaphragm, the major effector muscle of respiration, from fatigue, tetanic fade, and muscular paralysis. Protection against the paralyzing effects of VX was dose-dependent. In EEG studies, GAL did not alter seizure onset for all doses tested. At the highest dose tested (10 mg/kg), GAL decreased seizure duration when administered as a post-exposure treatment 1 min after VX. GAL also reduced the high correlation associated between seizure activity and lethality after 2LD50 VX challenge. GAL may have additional benefits both centrally and peripherally that are unrelated to its established mechanism as a reversible acetylcholinesterase inhibitor (AChEI).

  10. Lethal factor, but not edema factor, is required to cause fatal anthrax in cynomolgus macaques after pulmonary spore challenge.

    Science.gov (United States)

    Hutt, Julie A; Lovchik, Julie A; Drysdale, Melissa; Sherwood, Robert L; Brasel, Trevor; Lipscomb, Mary F; Lyons, C Rick

    2014-12-01

    Inhalational anthrax is caused by inhalation of Bacillus anthracis spores. The ability of B. anthracis to cause anthrax is attributed to the plasmid-encoded A/B-type toxins, edema toxin (edema factor and protective antigen) and lethal toxin (lethal factor and protective antigen), and a poly-d-glutamic acid capsule. To better understand the contribution of these toxins to the disease pathophysiology in vivo, we used B. anthracis Ames strain and isogenic toxin deletion mutants derived from the Ames strain to examine the role of lethal toxin and edema toxin after pulmonary spore challenge of cynomolgus macaques. Lethal toxin, but not edema toxin, was required to induce sustained bacteremia and death after pulmonary challenge with spores delivered via bronchoscopy. After intravenous challenge with bacilli to model the systemic phase of infection, lethal toxin contributed to bacterial proliferation and subsequent host death to a greater extent than edema toxin. Deletion of protective antigen resulted in greater loss of virulence after intravenous challenge with bacilli than deletion of lethal toxin or edema toxin alone. These findings are consistent with the ability of anti-protective antigen antibodies to prevent anthrax and suggest that lethal factor is the dominant toxin that contributes to the escape of significant numbers of bacilli from the thoracic cavity to cause anthrax after inhalation challenge with spores.

  11. Ebolavirus Glycoprotein Fc Fusion Protein Protects Guinea Pigs against Lethal Challenge.

    Science.gov (United States)

    Konduru, Krishnamurthy; Shurtleff, Amy C; Bradfute, Steven B; Nakamura, Siham; Bavari, Sina; Kaplan, Gerardo

    2016-01-01

    Ebola virus (EBOV), a member of the Filoviridae that can cause severe hemorrhagic fever in humans and nonhuman primates, poses a significant threat to the public health. Currently, there are no licensed vaccines or therapeutics to prevent and treat EBOV infection. Several vaccines based on the EBOV glycoprotein (GP) are under development, including vectored, virus-like particles, and protein-based subunit vaccines. We previously demonstrated that a subunit vaccine containing the extracellular domain of the Ebola ebolavirus (EBOV) GP fused to the Fc fragment of human IgG1 (EBOVgp-Fc) protected mice against EBOV lethal challenge. Here, we show that the EBOVgp-Fc vaccine formulated with QS-21, alum, or polyinosinic-polycytidylic acid-poly-L-lysine carboxymethylcellulose (poly-ICLC) adjuvants induced strong humoral immune responses in guinea pigs. The vaccinated animals developed anti-GP total antibody titers of approximately 105-106 and neutralizing antibody titers of approximately 103 as assessed by a BSL-2 neutralization assay based on vesicular stomatitis virus (VSV) pseudotypes. The poly-ICLC formulated EBOVgp-Fc vaccine protected all the guinea pigs against EBOV lethal challenge performed under BSL-4 conditions whereas the same vaccine formulated with QS-21 or alum only induced partial protection. Vaccination with a mucin-deleted EBOVgp-Fc construct formulated with QS-21 adjuvant did not have a significant effect in anti-GP antibody levels and protection against EBOV lethal challenge compared to the full-length GP construct. The bulk of the humoral response induced by the EBOVgp-Fc vaccine was directed against epitopes outside the EBOV mucin region. Our findings indicate that different adjuvants can eliciting varying levels of protection against lethal EBOV challenge in guinea pigs vaccinated with EBOVgp-Fc, and suggest that levels of total anti-GP antibodies elicit by protein-based GP subunit vaccines do not correlate with protection. Our data further support

  12. Antimalarial potential of China 30 and Chelidonium 30 in combination therapy against lethal rodent malaria parasite: Plasmodium berghei.

    Science.gov (United States)

    Rajan, Aswathy; Bagai, Upma

    2013-05-07

    Homeopathy is a therapeutic method based on the application of similia principle, utilizing ultra-low doses of medicinal substances made from natural products. The present study has been designed to evaluate the efficacy of Cinchona officinalis (Chin.) 30C and Chelidonium majus (Chel.) 30C in combination therapy against lethal murine malaria. Five groups having twelve BALB/c mice each were administered orally with 0.2 ml/mouse/day of different drugs, and their antimalarial potential was evaluated by Peter's 4-day test. The combination of Chin. 30 and Chel. 30 exhibited complete parasite clearance by the 28th day post-inoculation which was similar to the positive control [artesunate (4 mg/kg)+sulphadoxine-primethamine (1.2 mg/kg)] group. Both the groups exhibited enhanced mean survival time (MST) 28±0 days,whereas, the mice of infected control group survived up to 7.6±0.4 days only. The preventive and curative activities of the combination in comparison to the positive controls [pyrimethamine (1.2 mg/Kg) and chloroquine (20 mg/Kg), respectively] were also evaluated. The combination had a significant preventive activity (p<0.0005), with 89.2% chemosuppression which was higher than the standard drug, pyrimethamine (83.8%). It also showed a moderate curative activity with complete clearance of parasite in 50% of surviving mice, and enhancing the MST of mice up to 26.8±2.8 days. These findings point to the significant antiplasmodial efficacy of the combination of these homeopathic drugs against Plasmodium berghei.

  13. A novel DNA vaccine technology conveying protection against a lethal herpes simplex viral challenge in mice.

    Directory of Open Access Journals (Sweden)

    Julie L Dutton

    Full Text Available While there are a number of licensed veterinary DNA vaccines, to date, none have been licensed for use in humans. Here, we demonstrate that a novel technology designed to enhance the immunogenicity of DNA vaccines protects against lethal herpes simplex virus 2 (HSV-2 challenge in a murine model. Polynucleotides were modified by use of a codon optimization algorithm designed to enhance immune responses, and the addition of an ubiquitin-encoding sequence to target the antigen to the proteasome for processing and to enhance cytotoxic T cell responses. We show that a mixture of these codon-optimized ubiquitinated and non-ubiquitinated constructs encoding the same viral envelope protein, glycoprotein D, induced both B and T cell responses, and could protect against lethal viral challenge and reduce ganglionic latency. The optimized vaccines, subcloned into a vector suitable for use in humans, also provided a high level of protection against the establishment of ganglionic latency, an important correlate of HSV reactivation and candidate endpoint for vaccines to proceed to clinical trials.

  14. DNA vaccination partially protects against African swine fever virus lethal challenge in the absence of antibodies.

    Directory of Open Access Journals (Sweden)

    Jordi M Argilaguet

    Full Text Available The lack of available vaccines against African swine fever virus (ASFV means that the evaluation of new immunization strategies is required. Here we show that fusion of the extracellular domain of the ASFV Hemagglutinin (sHA to p54 and p30, two immunodominant structural viral antigens, exponentially improved both the humoral and the cellular responses induced in pigs after DNA immunization. However, immunization with the resulting plasmid (pCMV-sHAPQ did not confer protection against lethal challenge with the virulent E75 ASFV-strain. Due to the fact that CD8(+ T-cell responses are emerging as key components for ASFV protection, we designed a new plasmid construct, pCMV-UbsHAPQ, encoding the three viral determinants above mentioned (sHA, p54 and p30 fused to ubiquitin, aiming to improve Class I antigen presentation and to enhance the CTL responses induced. As expected, immunization with pCMV-UbsHAPQ induced specific T-cell responses in the absence of antibodies and, more important, protected a proportion of immunized-pigs from lethal challenge with ASFV. In contrast with control pigs, survivor animals showed a peak of CD8(+ T-cells at day 3 post-infection, coinciding with the absence of viremia at this time point. Finally, an in silico prediction of CTL peptides has allowed the identification of two SLA I-restricted 9-mer peptides within the hemagglutinin of the virus, capable of in vitro stimulating the specific secretion of IFNγ when using PBMCs from survivor pigs. Our results confirm the relevance of T-cell responses in protection against ASF and open new expectations for the future development of more efficient recombinant vaccines against this disease.

  15. DNA vaccination partially protects against African swine fever virus lethal challenge in the absence of antibodies.

    Science.gov (United States)

    Argilaguet, Jordi M; Pérez-Martín, Eva; Nofrarías, Miquel; Gallardo, Carmina; Accensi, Francesc; Lacasta, Anna; Mora, Mercedes; Ballester, Maria; Galindo-Cardiel, Ivan; López-Soria, Sergio; Escribano, José M; Reche, Pedro A; Rodríguez, Fernando

    2012-01-01

    The lack of available vaccines against African swine fever virus (ASFV) means that the evaluation of new immunization strategies is required. Here we show that fusion of the extracellular domain of the ASFV Hemagglutinin (sHA) to p54 and p30, two immunodominant structural viral antigens, exponentially improved both the humoral and the cellular responses induced in pigs after DNA immunization. However, immunization with the resulting plasmid (pCMV-sHAPQ) did not confer protection against lethal challenge with the virulent E75 ASFV-strain. Due to the fact that CD8(+) T-cell responses are emerging as key components for ASFV protection, we designed a new plasmid construct, pCMV-UbsHAPQ, encoding the three viral determinants above mentioned (sHA, p54 and p30) fused to ubiquitin, aiming to improve Class I antigen presentation and to enhance the CTL responses induced. As expected, immunization with pCMV-UbsHAPQ induced specific T-cell responses in the absence of antibodies and, more important, protected a proportion of immunized-pigs from lethal challenge with ASFV. In contrast with control pigs, survivor animals showed a peak of CD8(+) T-cells at day 3 post-infection, coinciding with the absence of viremia at this time point. Finally, an in silico prediction of CTL peptides has allowed the identification of two SLA I-restricted 9-mer peptides within the hemagglutinin of the virus, capable of in vitro stimulating the specific secretion of IFNγ when using PBMCs from survivor pigs. Our results confirm the relevance of T-cell responses in protection against ASF and open new expectations for the future development of more efficient recombinant vaccines against this disease.

  16. Immunization of Mice with Anthrax Protective Antigen Limits Cardiotoxicity but Not Hepatotoxicity Following Lethal Toxin Challenge.

    Science.gov (United States)

    Devera, T Scott; Prusator, Dawn K; Joshi, Sunil K; Ballard, Jimmy D; Lang, Mark L

    2015-06-25

    Protective immunity against anthrax is inferred from measurement of vaccine antigen-specific neutralizing antibody titers in serum samples. In animal models, in vivo challenges with toxin and/or spores can also be performed. However, neither of these approaches considers toxin-induced damage to specific organ systems. It is therefore important to determine to what extent anthrax vaccines and existing or candidate adjuvants can provide organ-specific protection against intoxication. We therefore compared the ability of Alum, CpG DNA and the CD1d ligand α-galactosylceramide (αGC) to enhance protective antigen-specific antibody titers, to protect mice against challenge with lethal toxin, and to block cardiotoxicity and hepatotoxicity. By measurement of serum cardiac Troponin I (cTnI), and hepatic alanine aminotransferase (ALT), and aspartate aminotransferase (AST), it was apparent that neither vaccine modality prevented hepatic intoxication, despite high Ab titers and ultimate survival of the subject. In contrast, cardiotoxicity was greatly diminished by prior immunization. This shows that a vaccine that confers survival following toxin exposure may still have an associated morbidity. We propose that organ-specific intoxication should be monitored routinely during research into new vaccine modalities.

  17. Immunization with a live attenuated H7N9 influenza vaccine protects mice against lethal challenge.

    Directory of Open Access Journals (Sweden)

    Xiaolan Yang

    Full Text Available The emergence of severe cases of human influenza A (H7N9 viral infection in China in the spring of 2003 resulted in a global effort to rapidly develop an effective candidate vaccine. In this study, a cold-adapted (ca, live attenuated monovalent reassortant influenza H7N9 virus (Ah01/AA ca was generated using reverse genetics that contained hemagglutinin (HA and neuraminidase (NA genes from a 2013 pandemic A H7N9 isolate, A/Anhui/01/2013 virus (Ah01/H7N9; the remaining six backbone genes derived from the cold-adapted influenza H2N2 A/Ann Arbor/6/60 virus (AA virus. Ah01/AA ca virus exhibited temperature sensitivity (ts, ca, and attenuation (att phenotypes. Intranasal immunization of female BALB/c mice with Ah01/AA ca twice at a 2-week interval induced robust humoral, mucosal, and cell-mediated immune responses in a dose-dependent manner. Furthermore, the candidate Ah01/AA ca virus was immunogenic and offered partial or complete protection of mice against a lethal challenge by the live 2013 influenza A H7N9 (A/Anhui/01/2013. Protection was demonstrated by the inhibition of viral replication and the attenuation of histopathological changes in the challenged mouse lung. Taken together, these data support the further evaluation of this Ah01/AA ca candidate vaccine in primates.

  18. RNA interference in protozoan parasites: achievements and challenges.

    Science.gov (United States)

    Kolev, Nikolay G; Tschudi, Christian; Ullu, Elisabetta

    2011-09-01

    Protozoan parasites that profoundly affect mankind represent an exceptionally diverse group of organisms, including Plasmodium, Toxoplasma, Entamoeba, Giardia, trypanosomes, and Leishmania. Despite the overwhelming impact of these parasites, there remain many aspects to be discovered about mechanisms of pathogenesis and how these organisms survive in the host. Combined with the ever-increasing availability of sequenced genomes, RNA interference (RNAi), discovered a mere 13 years ago, has enormously facilitated the analysis of gene function, especially in organisms that are not amenable to classical genetic approaches. Here we review the current status of RNAi in studies of parasitic protozoa, with special emphasis on its use as a postgenomic tool.

  19. The VG/GA strain of Newcastle disease virus: Mucosal immunity, protection against lethal challenge and molecular analysis

    Science.gov (United States)

    The VG/GA strain of Newcastle disease virus (NDV) isolated from the intestine of healthy turkeys has been proposed to replicate in the respiratory and intestinal tract of chickens. In this study, the virus distribution, the mucosal and systemic immune response, the efficacy against lethal challenge...

  20. Parasitic infections in HIV infected individuals: Diagnostic & therapeutic challenges

    OpenAIRE

    Nissapatorn, Veeranoot; Sawangjaroen, Nongyao

    2011-01-01

    After 30 years of the human immunodeficiency virus (HIV) epidemic, parasites have been one of the most common opportunistic infections (OIs) and one of the most frequent causes of morbidity and mortality associated with HIV-infected patients. Due to severe immunosuppression, enteric parasitic pathogens in general are emerging and are OIs capable of causing diarrhoeal disease associated with HIV. Of these, Cryptosporidium parvum and Isospora belli are the two most common intestinal protozoan p...

  1. Codon-optimized filovirus DNA vaccines delivered by intramuscular electroporation protect cynomolgus macaques from lethal Ebola and Marburg virus challenges.

    Science.gov (United States)

    Grant-Klein, Rebecca J; Altamura, Louis A; Badger, Catherine V; Bounds, Callie E; Van Deusen, Nicole M; Kwilas, Steven A; Vu, Hong A; Warfield, Kelly L; Hooper, Jay W; Hannaman, Drew; Dupuy, Lesley C; Schmaljohn, Connie S

    2015-01-01

    Cynomolgus macaques were vaccinated by intramuscular electroporation with DNA plasmids expressing codon-optimized glycoprotein (GP) genes of Ebola virus (EBOV) or Marburg virus (MARV) or a combination of codon-optimized GP DNA vaccines for EBOV, MARV, Sudan virus and Ravn virus. When measured by ELISA, the individual vaccines elicited slightly higher IgG responses to EBOV or MARV than did the combination vaccines. No significant differences in immune responses of macaques given the individual or combination vaccines were measured by pseudovirion neutralization or IFN-γ ELISpot assays. Both the MARV and mixed vaccines were able to protect macaques from lethal MARV challenge (5/6 vs. 6/6). In contrast, a greater proportion of macaques vaccinated with the EBOV vaccine survived lethal EBOV challenge in comparison to those that received the mixed vaccine (5/6 vs. 1/6). EBOV challenge survivors had significantly higher pre-challenge neutralizing antibody titers than those that succumbed.

  2. Intranasal immunisation with recombinant adenovirus vaccines protects against a lethal challenge with pneumonia virus of mice.

    Science.gov (United States)

    Maunder, Helen E; Taylor, Geraldine; Leppard, Keith N; Easton, Andrew J

    2015-11-27

    Pneumonia virus of mice (PVM) infection of BALB/c mice induces bronchiolitis leading to a fatal pneumonia in a dose-dependent manner, closely paralleling the development of severe disease during human respiratory syncytial virus infection in man, and is thus a recognised model in which to study the pathogenesis of pneumoviruses. This model system was used to investigate delivery of the internal structural proteins of PVM as a potential vaccination strategy to protect against pneumovirus disease. Replication-deficient recombinant human adenovirus serotype 5 (rAd5) vectors were constructed that expressed the M or N gene of PVM pathogenic strain J3666. Intranasal delivery of these rAd5 vectors gave protection against a lethal challenge dose of PVM in three different mouse strains, and protection lasted for at least 20 weeks post-immunisation. Whilst the PVM-specific antibody response in such animals was weak and inconsistent, rAd5N primed a strong PVM-specific CD8(+) T cell response and, to a lesser extent, a CD4(+) T cell response. These findings suggest that T-cell responses may be more important than serum IgG in the observed protection induced by rAd5N.

  3. Vaccination with self-adjuvanted protein nanoparticles provides protection against lethal influenza challenge.

    Science.gov (United States)

    Karch, Christopher P; Li, Jianping; Kulangara, Caroline; Paulillo, Sara M; Raman, Senthil K; Emadi, Sharareh; Tan, Anmin; Helal, Zeinab H; Fan, Qing; Khan, Mazhar I; Burkhard, Peter

    2017-01-01

    Current influenza vaccines should be improved by the addition of universal influenza vaccine antigens in order to protect against multiple virus strains. We used our self-assembling protein nanoparticles (SAPNs) to display the two conserved influenza antigens M2e and Helix C in their native oligomerization states. To further improve the immunogenicity of the SAPNs, we designed and incorporated the TLR5 agonist flagellin into the SAPNs to generate self-adjuvanted SAPNs. We demonstrate that addition of flagellin does not affect the ability of SAPNs to self-assemble and that they are able to stimulate TLR5 in a dose-dependent manner. Chickens vaccinated with the self-adjuvanted SAPNs induce significantly higher levels of antibodies than those with unadjuvanted SAPNs and show higher cross-neutralizing activity compared to a commercial inactivated virus vaccine. Upon immunization with self-adjuvanted SAPNs, mice were completely protected against a lethal challenge. Thus, we have generated a self-adjuvanted SAPN with a great potential as a universal influenza vaccine.

  4. Recombinant measles virus vaccine expressing the Nipah virus glycoprotein protects against lethal Nipah virus challenge.

    Directory of Open Access Journals (Sweden)

    Misako Yoneda

    Full Text Available Nipah virus (NiV is a member of the genus Henipavirus, which emerged in Malaysia in 1998. In pigs, infection resulted in a predominantly non-lethal respiratory disease; however, infection in humans resulted in over 100 deaths. Nipah virus has continued to re-emerge in Bangladesh and India, and person-to-person transmission appeared in the outbreak. Although a number of NiV vaccine studies have been reported, there are currently no vaccines or treatments licensed for human use. In this study, we have developed a recombinant measles virus (rMV vaccine expressing NiV envelope glycoproteins (rMV-HL-G and rMV-Ed-G. Vaccinated hamsters were completely protected against NiV challenge, while the mortality of unvaccinated control hamsters was 90%. We trialed our vaccine in a non-human primate model, African green monkeys. Upon intraperitoneal infection with NiV, monkeys showed several clinical signs of disease including severe depression, reduced ability to move and decreased food ingestion and died at 7 days post infection (dpi. Intranasal and oral inoculation induced similar clinical illness in monkeys, evident around 9 dpi, and resulted in a moribund stage around 14 dpi. Two monkeys immunized subcutaneously with rMV-Ed-G showed no clinical illness prior to euthanasia after challenge with NiV. Viral RNA was not detected in any organ samples collected from vaccinated monkeys, and no pathological changes were found upon histopathological examination. From our findings, we propose that rMV-NiV-G is an appropriate NiV vaccine candidate for use in humans.

  5. Recombinant measles virus vaccine expressing the Nipah virus glycoprotein protects against lethal Nipah virus challenge.

    Science.gov (United States)

    Yoneda, Misako; Georges-Courbot, Marie-Claude; Ikeda, Fusako; Ishii, Miho; Nagata, Noriyo; Jacquot, Frederic; Raoul, Hervé; Sato, Hiroki; Kai, Chieko

    2013-01-01

    Nipah virus (NiV) is a member of the genus Henipavirus, which emerged in Malaysia in 1998. In pigs, infection resulted in a predominantly non-lethal respiratory disease; however, infection in humans resulted in over 100 deaths. Nipah virus has continued to re-emerge in Bangladesh and India, and person-to-person transmission appeared in the outbreak. Although a number of NiV vaccine studies have been reported, there are currently no vaccines or treatments licensed for human use. In this study, we have developed a recombinant measles virus (rMV) vaccine expressing NiV envelope glycoproteins (rMV-HL-G and rMV-Ed-G). Vaccinated hamsters were completely protected against NiV challenge, while the mortality of unvaccinated control hamsters was 90%. We trialed our vaccine in a non-human primate model, African green monkeys. Upon intraperitoneal infection with NiV, monkeys showed several clinical signs of disease including severe depression, reduced ability to move and decreased food ingestion and died at 7 days post infection (dpi). Intranasal and oral inoculation induced similar clinical illness in monkeys, evident around 9 dpi, and resulted in a moribund stage around 14 dpi. Two monkeys immunized subcutaneously with rMV-Ed-G showed no clinical illness prior to euthanasia after challenge with NiV. Viral RNA was not detected in any organ samples collected from vaccinated monkeys, and no pathological changes were found upon histopathological examination. From our findings, we propose that rMV-NiV-G is an appropriate NiV vaccine candidate for use in humans.

  6. Acute infection with venezuelan equine encephalitis virus replicon particles catalyzes a systemic antiviral state and protects from lethal virus challenge.

    Science.gov (United States)

    Konopka, Jennifer L; Thompson, Joseph M; Whitmore, Alan C; Webb, Drue L; Johnston, Robert E

    2009-12-01

    The host innate immune response provides a critical first line of defense against invading pathogens, inducing an antiviral state to impede the spread of infection. While numerous studies have documented antiviral responses within actively infected tissues, few have described the earliest innate response induced systemically by infection. Here, utilizing Venezuelan equine encephalitis virus (VEE) replicon particles (VRP) to limit infection to the initially infected cells in vivo, a rapid activation of the antiviral response was demonstrated not only within the murine draining lymph node, where replication was confined, but also within distal tissues. In the liver and brain, expression of interferon-stimulated genes was detected by 1 to 3 h following VRP footpad inoculation, reaching peak expression of >100-fold over that in mock-infected animals. Moreover, mice receiving a VRP footpad inoculation 6, 12, or 24 h prior to an otherwise lethal VEE footpad challenge were completely protected from death, including a drastic reduction in challenge virus titers. VRP pretreatment also provided protection from intranasal VEE challenge and extended the average survival time following intracranial challenge. Signaling through the interferon receptor was necessary for antiviral gene induction and protection from VEE challenge. However, VRP pretreatment failed to protect mice from a heterologous, lethal challenge with vesicular stomatitis virus, yet conferred protection following challenge with influenza virus. Collectively, these results document a rapid modulation of the host innate response within hours of infection, capable of rapidly alerting the entire animal to pathogen invasion and leading to protection from viral disease.

  7. Protection from lethal challenge in a neonatal mouse model by circulating recombinant form coxsackievirus A16 vaccine candidates

    Science.gov (United States)

    Li, Jingliang; Chang, Junliang; Liu, Xin; Yang, Jiaxin; Guo, Haoran; Wei, Wei

    2014-01-01

    Circulating coxsackievirus A16 (CA16) is a major cause of hand, foot and mouth disease (HFMD) in South-east Asia. At present, there is no vaccine against CA16. Pathogenic animal models that are sensitive to diverse circulating CA16 viruses would be desirable for vaccine development and evaluation. In this study, we isolated and characterized several circulating CA16 viruses from recent HFMD patients. These CA16 viruses currently circulating in humans were highly pathogenic in a newly developed neonatal mouse model; we also observed and analysed the pathogenesis of representative circulating recombinant form CA16 viruses. An inactivated CA16 vaccine candidate, formulated with alum adjuvant and containing submicrogram quantities of viral proteins, protected neonatal mice born to immunized female mice from lethal-dose challenge with a series of CA16 viruses. Further analysis of humoral immunity showed that antibody elicited from both the immunized dams and their pups could neutralize various lethal viruses by a cytopathic effect in vitro. Moreover, viral titres and loads in the tissues of challenged pups in the vaccine group were far lower than those in the control group, and some were undetectable. This lethal-challenge model using pathogenic CA16 viruses and the vaccine candidates that mediated protection in this model could be useful tools for the future development and evaluation of CA16 vaccines. PMID:24496826

  8. 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.

  9. [Toxoplasmosis, a parasitic zoonoses prevalent in Chile: count and challenges].

    Science.gov (United States)

    Mimica, Francisco; Muñoz-Zanzi, Claudia; Torres, Marisa; Padilla, Oslando

    2015-10-01

    Toxoplasmosis, cosmopolitan parasitic zoonosis often found in humans, is transmitted mainly by food and water, and is considered a significant risk of morbidity and mortality in pregnant women, newborns and immunocompromised patients. To identify the information about this zoonosis and its first reports in Chile. Review of publications in Pubmed, Mesh search of systematic reviews, case studies, cross-sectional studies, systematic reviews, meta-analysis and specialty publications. In addition, other publications in parasitology journals were analyzed. There are reports of the presence of this disease in Chile for 60 years. During this time several differences in prevalence depending on geographic location, age and education level of the population have been detected. There is low epidemiological vigilance and lack of specific official preventive measures for this disease, despite the possible introduction of new parasite genotypes of an increased virulence and pathogenicity in the country through the importation of meat. New enigmas have arisen in relation to this disease associating it with Alzheimer, Parkinson's disease, autism, learning disabilities, among others.

  10. Diagnostic challenges and the unwritten stories of dog and cat parasites.

    Science.gov (United States)

    Otranto, Domenico

    2015-08-15

    Is it still possible to discover new parasites of dogs and cats? Do we really know enough about them? To what extent do limitations in the diagnosis of dog and cat parasites represent an obstacle for a deeper understanding of their biology? Diagnosis in parasitology has a profound impact on animal health and welfare and, in some cases, public health. Although, over the last few years, advances in the diagnosis of parasitic diseases have largely paralleled knowledge of their biology, gaps in the diagnosis of cat and dog parasites still exist. For instance, difficulties in obtaining samples for research purposes (due to ethical issues or to the invasive nature of the sampling procedures), inappropriate sample storage and poor sensitivity of the commonly used techniques, may represent major obstacles in diagnosing parasitic diseases. Other hurdles are often associated with the biology of parasites (e.g., the intermittent presence in blood of tick-borne pathogens) or, simply, through the fact that some parasites of pets are largely ignored by the scientific community. This article provides key examples of parasites of dogs and cats, which are currently considered of minor importance, also because of the limitations in their diagnosis. Among them, new or, in some cases, previously "misdiagnosed parasites" with overlapping morphological features, biology or ecology, represent a major challenge when trying to correctly diagnose "unknown parasites" (for which only occasional reports are available). Further research is needed in order to provide the scientific community with more reliable, cost-effective diagnostic tools, which ultimately, will assist our understanding of some mis- or less-diagnosed parasitoses.

  11. Adenovirus Vectors Expressing Hantavirus Proteins Protect Hamsters against Lethal Challenge with Andes Virus ▿

    OpenAIRE

    2009-01-01

    Hantaviruses infect humans following aerosolization from rodent feces and urine, producing hemorrhagic fever with renal syndrome and hantavirus pulmonary syndrome. Due to the high rates of mortality and lack of therapies, vaccines are urgently needed. Nonreplicating adenovirus (Ad) vectors that express Andes hantavirus (ANDV) nucleocapsid protein (AdN) or glycoproteins (AdGN and AdGC) were constructed. Ad vectors were tested for their ability to protect Syrian hamsters from a lethal ANDV infe...

  12. Recombinant Measles Virus Vaccine Expressing the Nipah Virus Glycoprotein Protects against Lethal Nipah Virus Challenge

    OpenAIRE

    Misako Yoneda; Marie-Claude Georges-Courbot; Fusako Ikeda; Miho Ishii; Noriyo Nagata; Frederic Jacquot; Hervé Raoul; Hiroki Sato; Chieko Kai

    2013-01-01

    Nipah virus (NiV) is a member of the genus Henipavirus, which emerged in Malaysia in 1998. In pigs, infection resulted in a predominantly non-lethal respiratory disease; however, infection in humans resulted in over 100 deaths. Nipah virus has continued to re-emerge in Bangladesh and India, and person-to-person transmission appeared in the outbreak. Although a number of NiV vaccine studies have been reported, there are currently no vaccines or treatments licensed for human use. In this study,...

  13. A novel vaccine against Crimean-Congo Haemorrhagic Fever protects 100% of animals against lethal challenge in a mouse model.

    Directory of Open Access Journals (Sweden)

    Karen R Buttigieg

    Full Text Available Crimean-Congo Haemorrhagic Fever (CCHF is a severe tick-borne disease, endemic in many countries in Africa, the Middle East, Eastern Europe and Asia. Between 15-70% of reported cases are fatal. There is no approved vaccine available, and preclinical protection in vivo by an experimental vaccine has not been demonstrated previously. In the present study, the attenuated poxvirus vector, Modified Vaccinia virus Ankara, was used to develop a recombinant candidate vaccine expressing the CCHF virus glycoproteins. Cellular and humoral immunogenicity was confirmed in two mouse strains, including type I interferon receptor knockout mice, which are susceptible to CCHF disease. This vaccine protected all recipient animals from lethal disease in a challenge model adapted to represent infection via a tick bite. Histopathology and viral load analysis of protected animals confirmed that they had been exposed to challenge virus, even though they did not exhibit clinical signs. This is the first demonstration of efficacy of a CCHF vaccine.

  14. Mouse dendritic cells pulsed with capsular polysaccharide induce resistance to lethal pneumococcal challenge: roles of T cells and B cells.

    Directory of Open Access Journals (Sweden)

    Noam Cohen

    Full Text Available Mice are exceedingly sensitive to intra-peritoneal (IP challenge with some virulent pneumococci (LD50 = 1 bacterium. To investigate how peripheral contact with bacterial capsular polysaccharide (PS antigen can induce resistance, we pulsed bone marrow dendritic cells (BMDC of C57BL/6 mice with type 4 or type 3 PS, injected the BMDC intra-foot pad (IFP and challenged the mice IP with supra-lethal doses of pneumococci. We examined the responses of T cells and B cells in the draining popliteal lymph node and measured the effects on the bacteria in the peritoneum and blood. We now report that: 1 The PS co-localized with MHC molecules on the BMDC surface; 2 PS-specific T and B cell proliferation and IFNγ secretion was detected in the draining popliteal lymph nodes on day 4; 3 Type-specific resistance to lethal IP challenge was manifested only after day 5; 4 Type-specific IgM and IgG antibodies were detected in the sera of only some of the mice, but B cells were essential for resistance; 5 Control mice vaccinated with a single injection of soluble PS did not develop a response in the draining popliteal lymph node and were not protected; 6 Mice injected with unpulsed BMDC also did not resist challenge: In unprotected mice, pneumococci entered the blood shortly after IP inoculation and multiplied exponentially in both blood and peritoneum killing the mice within 20 hours. Mice vaccinated with PS-pulsed BMDC trapped the bacteria in the peritoneum. The trapped bacteria proliferated exponentially IP, but died suddenly at 18-20 hours. Thus, a single injection of PS antigen associated with intact BMDC is a more effective vaccine than the soluble PS alone. This model system provides a platform for studying novel aspects of PS-targeted vaccination.

  15. Mouse dendritic cells pulsed with capsular polysaccharide induce resistance to lethal pneumococcal challenge: roles of T cells and B cells.

    Science.gov (United States)

    Cohen, Noam; Margalit, Raanan; Pevsner-Fischer, Meirav; Yona, Simon; Jung, Steffen; Eisenbach, Lea; Cohen, Irun R

    2012-01-01

    Mice are exceedingly sensitive to intra-peritoneal (IP) challenge with some virulent pneumococci (LD50 = 1 bacterium). To investigate how peripheral contact with bacterial capsular polysaccharide (PS) antigen can induce resistance, we pulsed bone marrow dendritic cells (BMDC) of C57BL/6 mice with type 4 or type 3 PS, injected the BMDC intra-foot pad (IFP) and challenged the mice IP with supra-lethal doses of pneumococci. We examined the responses of T cells and B cells in the draining popliteal lymph node and measured the effects on the bacteria in the peritoneum and blood. We now report that: 1) The PS co-localized with MHC molecules on the BMDC surface; 2) PS-specific T and B cell proliferation and IFNγ secretion was detected in the draining popliteal lymph nodes on day 4; 3) Type-specific resistance to lethal IP challenge was manifested only after day 5; 4) Type-specific IgM and IgG antibodies were detected in the sera of only some of the mice, but B cells were essential for resistance; 5) Control mice vaccinated with a single injection of soluble PS did not develop a response in the draining popliteal lymph node and were not protected; 6) Mice injected with unpulsed BMDC also did not resist challenge: In unprotected mice, pneumococci entered the blood shortly after IP inoculation and multiplied exponentially in both blood and peritoneum killing the mice within 20 hours. Mice vaccinated with PS-pulsed BMDC trapped the bacteria in the peritoneum. The trapped bacteria proliferated exponentially IP, but died suddenly at 18-20 hours. Thus, a single injection of PS antigen associated with intact BMDC is a more effective vaccine than the soluble PS alone. This model system provides a platform for studying novel aspects of PS-targeted vaccination.

  16. Select human anthrax protective antigen (PA) epitope-specific antibodies provide protection from lethal toxin challenge

    Science.gov (United States)

    Crowe, Sherry R.; Ash, Linda L.; Engler, Renata J. M.; Ballard, Jimmy D.; Harley, John B.; Farris, A. Darise; James, Judith A.

    2010-01-01

    Bacillus anthracis remains a serious bioterrorism concern, and the currently licensed vaccine remains an incomplete solution for population protection from inhalation anthrax and has been associated with concerns regarding efficacy and safety. Thus, understanding how to generate long lasting protective immunity with reduced immunizations or providing protection through post exposure immunotherapeutics are long sought goals. Through evaluation of a large military cohort, we characterized the levels of antibodies against protective antigen and found that over half of anthrax vaccinees had low levels of in vitro toxin neutralization capacity in their sera. Using solid phase epitope mapping and confirmatory assays, we identified several neutralization-associated humoral epitopes and demonstrated that select anti-peptide responses mediated protection in vitro. Finally, passively transferred antibodies specific for select epitopes provided protection in an in vivo lethal toxin mouse model. Identification of these antigenic regions has important implications for vaccine design and the development of directed immunotherapeutics. PMID:20533877

  17. Increased Resin Collection after Parasite Challenge: A Case of Self-Medication in Honey Bees?

    Science.gov (United States)

    Simone-Finstrom, Michael D.; Spivak, Marla

    2012-01-01

    The constant pressure posed by parasites has caused species throughout the animal kingdom to evolve suites of mechanisms to resist infection. Individual barriers and physiological defenses are considered the main barriers against parasites in invertebrate species. However, behavioral traits and other non-immunological defenses can also effectively reduce parasite transmission and infection intensity. In social insects, behaviors that reduce colony-level parasite loads are termed “social immunity.” One example of a behavioral defense is resin collection. Honey bees forage for plant-produced resins and incorporate them into their nest architecture. This use of resins can reduce chronic elevation of an individual bee's immune response. Since high activation of individual immunity can impose colony-level fitness costs, collection of resins may benefit both the individual and colony fitness. However the use of resins as a more direct defense against pathogens is unclear. Here we present evidence that honey bee colonies may self-medicate with plant resins in response to a fungal infection. Self-medication is generally defined as an individual responding to infection by ingesting or harvesting non-nutritive compounds or plant materials. Our results show that colonies increase resin foraging rates after a challenge with a fungal parasite (Ascophaera apis: chalkbrood or CB). Additionally, colonies experimentally enriched with resin had decreased infection intensities of this fungal parasite. If considered self-medication, this is a particularly unique example because it operates at the colony level. Most instances of self-medication involve pharmacophagy, whereby individuals change their diet in response to direct infection with a parasite. In this case with honey bees, resins are not ingested but used within the hive by adult bees exposed to fungal spores. Thus the colony, as the unit of selection, may be responding to infection through self-medication by increasing

  18. Increased resin collection after parasite challenge: a case of self-medication in honey bees?

    Science.gov (United States)

    Simone-Finstrom, Michael D; Spivak, Marla

    2012-01-01

    The constant pressure posed by parasites has caused species throughout the animal kingdom to evolve suites of mechanisms to resist infection. Individual barriers and physiological defenses are considered the main barriers against parasites in invertebrate species. However, behavioral traits and other non-immunological defenses can also effectively reduce parasite transmission and infection intensity. In social insects, behaviors that reduce colony-level parasite loads are termed "social immunity." One example of a behavioral defense is resin collection. Honey bees forage for plant-produced resins and incorporate them into their nest architecture. This use of resins can reduce chronic elevation of an individual bee's immune response. Since high activation of individual immunity can impose colony-level fitness costs, collection of resins may benefit both the individual and colony fitness. However the use of resins as a more direct defense against pathogens is unclear. Here we present evidence that honey bee colonies may self-medicate with plant resins in response to a fungal infection. Self-medication is generally defined as an individual responding to infection by ingesting or harvesting non-nutritive compounds or plant materials. Our results show that colonies increase resin foraging rates after a challenge with a fungal parasite (Ascophaera apis: chalkbrood or CB). Additionally, colonies experimentally enriched with resin had decreased infection intensities of this fungal parasite. If considered self-medication, this is a particularly unique example because it operates at the colony level. Most instances of self-medication involve pharmacophagy, whereby individuals change their diet in response to direct infection with a parasite. In this case with honey bees, resins are not ingested but used within the hive by adult bees exposed to fungal spores. Thus the colony, as the unit of selection, may be responding to infection through self-medication by increasing the

  19. Increased resin collection after parasite challenge: a case of self-medication in honey bees?

    Directory of Open Access Journals (Sweden)

    Michael D Simone-Finstrom

    Full Text Available The constant pressure posed by parasites has caused species throughout the animal kingdom to evolve suites of mechanisms to resist infection. Individual barriers and physiological defenses are considered the main barriers against parasites in invertebrate species. However, behavioral traits and other non-immunological defenses can also effectively reduce parasite transmission and infection intensity. In social insects, behaviors that reduce colony-level parasite loads are termed "social immunity." One example of a behavioral defense is resin collection. Honey bees forage for plant-produced resins and incorporate them into their nest architecture. This use of resins can reduce chronic elevation of an individual bee's immune response. Since high activation of individual immunity can impose colony-level fitness costs, collection of resins may benefit both the individual and colony fitness. However the use of resins as a more direct defense against pathogens is unclear. Here we present evidence that honey bee colonies may self-medicate with plant resins in response to a fungal infection. Self-medication is generally defined as an individual responding to infection by ingesting or harvesting non-nutritive compounds or plant materials. Our results show that colonies increase resin foraging rates after a challenge with a fungal parasite (Ascophaera apis: chalkbrood or CB. Additionally, colonies experimentally enriched with resin had decreased infection intensities of this fungal parasite. If considered self-medication, this is a particularly unique example because it operates at the colony level. Most instances of self-medication involve pharmacophagy, whereby individuals change their diet in response to direct infection with a parasite. In this case with honey bees, resins are not ingested but used within the hive by adult bees exposed to fungal spores. Thus the colony, as the unit of selection, may be responding to infection through self

  20. Successful vaccination strategies that protect aged mice from lethal challenge from influenza virus and heterologous severe acute respiratory syndrome coronavirus.

    Science.gov (United States)

    Sheahan, Timothy; Whitmore, Alan; Long, Kristin; Ferris, Martin; Rockx, Barry; Funkhouser, William; Donaldson, Eric; Gralinski, Lisa; Collier, Martha; Heise, Mark; Davis, Nancy; Johnston, Robert; Baric, Ralph S

    2011-01-01

    Newly emerging viruses often circulate as a heterogeneous swarm in wild animal reservoirs prior to their emergence in humans, and their antigenic identities are often unknown until an outbreak situation. The newly emerging severe acute respiratory syndrome coronavirus (SARS-CoV) and reemerging influenza virus cause disproportionate disease in the aged, who are also notoriously difficult to successfully vaccinate, likely due to immunosenescence. To protect against future emerging strains, vaccine platforms should induce broad cross-reactive immunity that is sufficient to protect from homologous and heterologous challenge in all ages. From initial studies, we hypothesized that attenuated Venezuelan equine encephalitis virus (VEE) replicon particle (VRP) vaccine glycoproteins mediated vaccine failure in the aged. We then compared the efficacies of vaccines bearing attenuated (VRP(3014)) or wild-type VEE glycoproteins (VRP(3000)) in young and aged mice within novel models of severe SARS-CoV pathogenesis. Aged animals receiving VRP(3000)-based vaccines were protected from SARS-CoV disease, while animals receiving the VRP(3014)-based vaccines were not. The superior protection for the aged observed with VRP(3000)-based vaccines was confirmed in a lethal influenza virus challenge model. While the VRP(3000) vaccine's immune responses in the aged were sufficient to protect against lethal homologous and heterologous challenge, our data suggest that innate defects within the VRP(3014) platform mediate vaccine failure. Exploration into the mechanism(s) of successful vaccination in the immunosenescent should aid in the development of successful vaccine strategies for other viral diseases disproportionately affecting the elderly, like West Nile virus, influenza virus, norovirus, or other emerging viruses of the future.

  1. Recombinant modified vaccinia virus Ankara expressing glycoprotein E2 of Chikungunya virus protects AG129 mice against lethal challenge.

    Directory of Open Access Journals (Sweden)

    Petra van den Doel

    2014-09-01

    Full Text Available Chikungunya virus (CHIKV infection is characterized by rash, acute high fever, chills, headache, nausea, photophobia, vomiting, and severe polyarthralgia. There is evidence that arthralgia can persist for years and result in long-term discomfort. Neurologic disease with fatal outcome has been documented, although at low incidences. The CHIKV RNA genome encodes five structural proteins (C, E1, E2, E3 and 6K. The E1 spike protein drives the fusion process within the cytoplasm, while the E2 protein is believed to interact with cellular receptors and therefore most probably constitutes the target of neutralizing antibodies. We have constructed recombinant Modified Vaccinia Ankara (MVA expressing E3E2, 6KE1, or the entire CHIKV envelope polyprotein cassette E3E26KE1. MVA is an appropriate platform because of its demonstrated clinical safety and its suitability for expression of various heterologous proteins. After completing the immunization scheme, animals were challenged with CHIV-S27. Immunization of AG129 mice with MVAs expressing E2 or E3E26KE1 elicited neutralizing antibodies in all animals and provided 100% protection against lethal disease. In contrast, 75% of the animals immunized with 6KE1 were protected against lethal infection. In conclusion, MVA expressing the glycoprotein E2 of CHIKV represents as an immunogenic and effective candidate vaccine against CHIKV infections.

  2. Recombinant rabies virus expressing the H protein of canine distemper virus protects dogs from the lethal distemper challenge.

    Science.gov (United States)

    Wang, Feng-Xue; Zhang, Shu-Qin; Zhu, Hong-Wei; Yang, Yong; Sun, Na; Tan, Bin; Li, Zhen-Guang; Cheng, Shi-Peng; Fu, Zhen F; Wen, Yong-Jun

    2014-12-05

    The rabies virus (RV) vector LBNSE expressing foreign antigens have shown considerable promise as vaccines against viral and bacteria diseases, which is effective and safe. We produced a new RV-based vaccine vehicle expressing 1.824 kb hemagglutinin (H) gene of the canine distemper virus (CDV) by reverse genetics technology. The recombinant virus LBNSE-CDV-H retained growth properties similar to those of vector LBNSE both in BSR and mNA cell culture. The H gene of CDV was expressed and detected by immunostaining. To compare the immunogenicity of LBNSE-CDV-H, dogs were immunized with each of these recombinant viruses by intramuscular (i.m.). The dogs were bled at third weeks after the immunization for the measurement of virus neutralizing antibody (VNA) and then challenged with virulent virus (ZJ 7) at fourth weeks. The parent virus (LBNSE) without expression of any foreign molecules was included for comparison. Dogs inoculated with LBNSE-CDV-H showed no any signs of disease and exhibited seroconversion against both RV and CDV H protein. The LBNSE-CDV-H did not cause disease in dogs and conferred protection from challenge with a lethal wild type CDV strain, demonstrating its potential value for wildlife conservation efforts. Together, these studies suggest that recombinant RV expressing H protein from CDV stimulated high levels of adaptive immune responses (VNA), and protected all dogs challenge infection.

  3. A recombinant DNA vaccine protects mice deficient in the alpha/beta interferon receptor against lethal challenge with Usutu virus.

    Science.gov (United States)

    Martín-Acebes, Miguel A; Blázquez, Ana-Belén; Cañas-Arranz, Rodrigo; Vázquez-Calvo, Ángela; Merino-Ramos, Teresa; Escribano-Romero, Estela; Sobrino, Francisco; Saiz, Juan-Carlos

    2016-04-19

    Usutu virus (USUV) is a mosquito-borne flavivirus whose circulation had been confined to Africa since it was first detected in 1959. However, in the last decade USUV has emerged in Europe causing episodes of avian mortality and sporadic severe neuroinvasive infections in humans. Remarkably, adult laboratory mice exhibit limited susceptibility to USUV infection, which has impaired the analysis of the immune responses, thus complicating the evaluation of virus-host interactions and of vaccine candidates against this pathogen. In this work, we showed that mice deficient in the alpha/beta interferon receptor (IFNAR (-/-) mice) were highly susceptible to USUV infection and provided a lethal challenge model for vaccine testing. To validate this infection model, a plasmid DNA vaccine candidate encoding the precursor of membrane (prM) and envelope (E) proteins of USUV was engineered. Transfection of cultured cells with this plasmid resulted in expression of USUV antigens and the assembly and secretion of small virus-like particles also known as recombinant subviral particles (RSPs). A single intramuscular immunization with this plasmid was sufficient to elicit a significant level of protection against challenge with USUV in IFNAR (-/-) mice. The characterization of the humoral response induced revealed that DNA vaccination primed anti-USUV antibodies, including neutralizing antibodies. Overall, these results probe the suitability of IFNAR (-/-) mice as an amenable small animal model for the study of USUV host virus interactions and vaccine testing, as well as the feasibility of DNA-based vaccine strategies for the control of this pathogen.

  4. Parasite management extension - challenging traditional practice through adoption of a systems approach.

    Science.gov (United States)

    Wilson, L; Rhodes, A P; Dodunski, G

    2015-11-01

    The drivers for anthelmintic use today are substantial and anthelmintic use has become an embedded normalised behaviour. The cheapness and easy availability of anthelmintic products has meant that New Zealand farmers have had access to easy "solutions" for dealing with parasites and minimal forward planning or system redesign has been required. Despite 30 years of messaging about the emerging issue of anthelmintic resistance, management to reduce parasitism and the need to change behaviour, farmer practice has largely remained unchanged. Traditional approaches to extension, particularly around parasite management, appear to have been quite ineffective, apart from encouraging change in anthelmintic products and a switch to use of anthelmintics in combination. More effective approaches are required. The evolving nature of anthelmintic resistance and sustainable management of parasitism require attitudes, knowledge and behaviour to change. This is a challenge for all players in the industry; researchers, manufacturers and sellers, advisors and farmers. Looking beyond agriculture to the health sector provides some insight into models of decision making and behaviour change that can inform future strategies. Features in the health belief model including concepts of self-efficacy and cues to action appear to align with the issues, challenges and culture prevailing in farming, and parasite management in particular. Programmes through which farmers have made substantial beneficial behaviour change and the lessons learnt are discussed. Effecting consistent behaviour change around parasite management will involve new approaches by all participants in the process. And the process itself also needs to change. It requires an understanding of whole-farm systems, and the consideration of all the sources of influence on the farmer and the other participants in the process. The process of knowledge sharing involving the farmer should be based on equality; each person in the process

  5. Hox genes and the parasitic flatworms: new opportunities, challenges and lessons from the free-living.

    Science.gov (United States)

    Olson, P D

    2008-03-01

    Research into the roles played by Hox and related homeotic gene families in the diverse and complex developmental programmes exhibited by parasitic flatworms (Platyhelminthes) can hardly be said to have begun, and thus presents considerable opportunity for new research. Although featured in some of the earliest screens for homeotic genes outside Drosophila and mice, surveys in parasitic flatworms are few in number and almost nothing is yet known of where or when the genes are expressed during ontogeny. This contrasts sharply with a significant body of literature concerning Hox genes in free-living flatworms which have long served as models for the study of regeneration and the maintenance of omnipotent cell lines. Nevertheless, available information suggests that the complement of Hox genes and other classes of homeobox-containing genes in parasitic flatworms is typical of their free-living cousins and of other members of the Lophotrochozoa. Recent work on Schistosoma combined with information on Hox gene expression in planarians indicates that at least some disruption of the clustered genomic arrangement of the genes, as well as of the strict spatial and temporal colinear patterns of expression typical in other groups, may be characteristic of flatworms. However, available data on the genomic arrangement and expression of flatworm Hox genes is so limited at present that such generalities are highly tenuous. Moreover, a basic underlying pattern of colinearity is still observed in their spatial expression patterns making them suitable as cell or region-specific markers. I discuss a number of fundamental developmental questions and some of the challenges to addressing them in relation to each of the major parasitic lineages. In addition, I present newly characterized Hox genes from the model tapeworm Hymenolepis and analyze these by Bayesian inference together with >100 Hox and ParaHox homeodomains of flatworms and select lophotrochozoan taxa, providing a

  6. Cross-protection against lethal H5N1 challenge in ferrets with an adjuvanted pandemic influenza vaccine.

    Directory of Open Access Journals (Sweden)

    Benoît Baras

    Full Text Available BACKGROUND: Unprecedented spread between birds and mammals of highly pathogenic avian influenza viruses (HPAI of the H5N1 subtype has resulted in hundreds of human infections with a high fatality rate. This has highlighted the urgent need for the development of H5N1 vaccines that can be produced rapidly and in sufficient quantities. Potential pandemic inactivated vaccines will ideally induce substantial intra-subtypic cross-protection in humans to warrant the option of use, either prior to or just after the start of a pandemic outbreak. In the present study, we evaluated a split H5N1 A/H5N1/Vietnam/1194/04, clade 1 candidate vaccine, adjuvanted with a proprietary oil-in- water emulsion based Adjuvant System proven to be well-tolerated and highly immunogenic in the human (Leroux-Roels et al. (2007 The Lancet 370:580-589, for its ability to induce intra-subtypic cross-protection against clade 2 H5N1/A/Indonesia/5/05 challenge in ferrets. METHODOLOGY AND PRINCIPAL FINDINGS: All ferrets in control groups receiving non-adjuvanted vaccine or adjuvant alone failed to develop specific or cross-reactive neutralizing antibodies and all died or had to be euthanized within four days of virus challenge. Two doses of adjuvanted split H5N1 vaccine containing >or=1.7 microg HA induced neutralizing antibodies in the majority of ferrets to both clade 1 (17/23 (74% responders and clade 2 viruses (14/23 (61% responders, and 96% (22/23 of vaccinees survived the lethal challenge. Furthermore lung virus loads and viral shedding in the upper respiratory tract were reduced in vaccinated animals relative to controls suggesting that vaccination might also confer a reduced risk of viral transmission. CONCLUSION: These protection data in a stringent challenge model in association with an excellent clinical profile highlight the potential of this adjuvanted H5N1 candidate vaccine as an effective tool in pandemic preparedness.

  7. Helminth parasites in pigs: new challenges in pig production and current research highlights.

    Science.gov (United States)

    Roepstorff, A; Mejer, H; Nejsum, P; Thamsborg, S M

    2011-08-04

    Helminths in pigs have generally received little attention from veterinary parasitologists, despite Ascaris suum, Trichuris suis, and Oesophagostomum sp. being common worldwide. The present paper presents challenges and current research highlights connected with these parasites. In Danish swine herds, new indoor production systems may favour helminth transmission and growing knowledge on pasture survival and infectivity of A. suum and T. suis eggs indicates that they may constitute a serious threat to outdoor pig production. Furthermore, it is now evident that A. suum is zoonotic and the same may be true for T. suis. With these 'new' challenges and the economic impact of the infections, further research is warranted. Better understanding of host-parasite relationships and A. suum and T. suis egg ecology may also improve the understanding and control of human A. lumbricoides and T. trichiura infections. The population dynamics of the three parasites are well documented and may be used to study phenomena, such as predisposition and worm aggregation. Furthermore, better methods to recover larvae have provided tools for quantifying parasite transmission. Thus, an on-going study using helminth naïve tracer pigs has surprisingly demonstrated that soil infectivity with A. suum and T. suis increases during the first 2-3 years after pasture contamination. Though all three helminth species stimulate the Th2 arm of the immune system, Oesophagostomum seems weakly immunogenic, perhaps via specific modulation of the host immune system. A. suum and T. suis potently modulate the host immune response, up-regulating Th2 and down-regulating Th1. As a consequence, A. suum may compromise the efficacy of certain bacterial vaccines, whereas T. suis, which establish only short-term in humans, is a favourite candidate for down-regulating autoimmune Th1-related diseases in man. Some basic research findings have offered new possibilities for future sustainable control measures. For example

  8. Recombinant M2e outer membrane vesicle vaccines protect against lethal influenza A challenge in BALB/c mice.

    Science.gov (United States)

    Rappazzo, C Garrett; Watkins, Hannah C; Guarino, Cassandra M; Chau, Annie; Lopez, Jody L; DeLisa, Matthew P; Leifer, Cynthia A; Whittaker, Gary R; Putnam, David

    2016-03-04

    Currently approved influenza vaccines predominantly protect through antibodies directed against the highly variable glycoprotein hemagglutinin (HA), necessitating annual redesign and formulation based on epidemiological prediction of predominant circulating strains. More conserved influenza protein sequences, such as the ectodomain of the influenza M2 protein, or M2e, show promise as a component of a universal influenza A vaccine, but require a Th1-biased immune response for activity. Recently, recombinant, bacterially derived outer membrane vesicles (OMVs) demonstrated potential as a platform to promote a Th1-biased immune response to subunit antigens. Here, we engineer three M2e-OMV vaccines and show that all elicit strong IgG titers, with high IgG2a:IgG1 ratios, in BALB/c mice. Additionally, the administration of one M2e-OMV construct containing tandem heterologous M2e peptides (M2e4xHet-OMV) resulted in 100% survival against lethal doses of the mouse-adapted H1N1 influenza strain PR8. Passive transfer of antibodies from M2e4xHet-OMV vaccinated mice to unvaccinated mice also resulted in 100% survival to challenge, indicating that protection is driven largely via antibody-mediated immunity. The potential mechanism through which M2e-OMVs initiated the immune response was explored and it was found that the constructs triggered TLR1/2, TLR4, and TLR5. Our data indicate that OMVs have potential as a platform for influenza A vaccine development due to their unique adjuvant profile and intrinsic pathogen-mimetic nature. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. BoHV-4-Based Vector Single Heterologous Antigen Delivery Protects STAT1(-/- Mice from Monkeypoxvirus Lethal Challenge.

    Directory of Open Access Journals (Sweden)

    Valentina Franceschi

    2015-06-01

    Full Text Available Monkeypox virus (MPXV is the etiological agent of human (MPX. It is an emerging orthopoxvirus zoonosis in the tropical rain forest of Africa and is endemic in the Congo-basin and sporadic in West Africa; it remains a tropical neglected disease of persons in impoverished rural areas. Interaction of the human population with wildlife increases human infection with MPX virus (MPXV, and infection from human to human is possible. Smallpox vaccination provides good cross-protection against MPX; however, the vaccination campaign ended in Africa in 1980, meaning that a large proportion of the population is currently unprotected against MPXV infection. Disease control hinges on deterring zoonotic exposure to the virus and, barring that, interrupting person-to-person spread. However, there are no FDA-approved therapies against MPX, and current vaccines are limited due to safety concerns. For this reason, new studies on pathogenesis, prophylaxis and therapeutics are still of great interest, not only for the scientific community but also for the governments concerned that MPXV could be used as a bioterror agent. In the present study, a new vaccination strategy approach based on three recombinant bovine herpesvirus 4 (BoHV-4 vectors, each expressing different MPXV glycoproteins, A29L, M1R and B6R were investigated in terms of protection from a lethal MPXV challenge in STAT1 knockout mice. BoHV-4-A-CMV-A29LgD106ΔTK, BoHV-4-A-EF1α-M1RgD106ΔTK and BoHV-4-A-EF1α-B6RgD106ΔTK were successfully constructed by recombineering, and their capacity to express their transgene was demonstrated. A small challenge study was performed, and all three recombinant BoHV-4 appeared safe (no weight-loss or obvious adverse events following intraperitoneal administration. Further, BoHV-4-A-EF1α-M1RgD106ΔTK alone or in combination with BoHV-4-A-CMV-A29LgD106ΔTK and BoHV-4-A-EF1α-B6RgD106ΔTK, was shown to be able to protect, 100% alone and 80% in combination, STAT1(-/- mice

  10. DNA vaccination with a gene encoding Toxoplasma gondii Rhoptry Protein 17 induces partial protective immunity against lethal challenge in mice

    Directory of Open Access Journals (Sweden)

    Wang Hai-Long

    2016-01-01

    Full Text Available Toxoplasma gondii is an obligate intracellular apicomplexan parasite that affects humans and various vertebrate livestock and causes serious economic losses. To develop an effective vaccine against T. gondii infection, we constructed a DNA vaccine encoding the T. gondii rhoptry protein 17 (TgROP17 and evaluated its immune protective efficacy against acute T. gondii infection in mice. The DNA vaccine (p3×Flag-CMV-14-ROP17 was intramuscularly injected to BALB/c mice and the immune responses of the vaccinated mice were determined. Compared to control mice treated with empty vector or PBS, mice immunized with the ROP17 vaccine showed a relatively high level of specific anti-T. gondii antibodies, and a mixed IgG1/IgG2a response with predominance of IgG2a production. The immunized mice also displayed a specific lymphocyte proliferative response, a Th1-type cellular immune response with production of IFN-γ and interleukin-2, and increased number of CD8+ T cells. Immunization with the ROP17 DNA significantly prolonged the survival time (15.6 ± 5.4 days, P < 0.05 of mice after challenge infection with the virulent T. gondii RH strain (Type I, compared with the control groups which died within 8 days. Therefore, our data suggest that DNA vaccination with TgROP17 triggers significant humoral and cellular responses and induces effective protection in mice against acute T. gondii infection, indicating that TgROP17 is a promising vaccine candidate against acute toxoplasmosis.

  11. Fine-tuning synthesis of Yersinia pestis LcrV from runaway-like replication balanced-lethal plasmid in a Salmonella enterica serovar typhimurium vaccine induces protection against a lethal Y. pestis challenge in mice.

    Science.gov (United States)

    Torres-Escobar, Ascención; Juárez-Rodríguez, María Dolores; Gunn, Bronwyn M; Branger, Christine G; Tinge, Steven A; Curtiss, Roy

    2010-06-01

    A balanced-lethal plasmid expression system that switches from low-copy-number to runaway-like high-copy-number replication (pYA4534) was constructed for the regulated delayed in vivo synthesis of heterologous antigens by vaccine strains. This is an antibiotic resistance-free maintenance system containing the asdA gene (essential for peptidoglycan synthesis) as a selectable marker to complement the lethal chromosomal DeltaasdA allele in live recombinant attenuated Salmonella vaccines (RASVs) such as Salmonella enterica serovar Typhimurium strain chi9447. pYA4534 harbors two origins of replication, pSC101 and pUC (low and high copy numbers, respectively). The pUC replication origin is controlled by a genetic switch formed by the operator/promoter of the P22 cro gene (O/P(cro)) (P(R)), which is negatively regulated by an arabinose-inducible P22 c2 gene located on both the plasmid and the chromosome (araC P(BAD) c2). The absence of arabinose, which is unavailable in vivo, triggers replication to a high-copy-number plasmid state. To validate these vector attributes, the Yersinia pestis virulence antigen LcrV was used to develop a vaccine against plague. An lcrV sequence encoding amino acids 131 to 326 (LcrV196) was optimized for expression in Salmonella, flanked with nucleotide sequences encoding the signal peptide (SS) and the carboxy-terminal domain (CT) of beta-lactamase, and cloned into pYA4534 under the control of the P(trc) promoter to generate plasmid pYA4535. Our results indicate that the live Salmonella vaccine strain chi9447 harboring pYA4535 efficiently stimulated a mixed Th1/Th2 immune response that protected mice against lethal challenge with Y. pestis strain CO92 introduced through either the intranasal or subcutaneous route.

  12. Immunization with a synthetic robustoxin derivative lacking disulphide bridges protects against a potentially lethal challenge with funnel-web spider (Atrax robustus) venom.

    Science.gov (United States)

    Comis, Alfio; Tyler, Margaret; Mylecharane, Ewan; Spence, Ian; Howden, Merlin

    2009-03-01

    The venom of male Atrax robustus spiders is potentially lethal to primates. These spiders have been responsible for a number of human deaths. Robustoxin is the lethal toxin in the venom. It is a highly cross-linked polypeptide that has 42 amino acid residues and four disulphide bridges. If these bridges are broken, the resulting polypeptide is non-toxic. Robustoxin was chemically synthesized with all of its eight cysteine residues protected with acetamidomethyl groups in order to avoid formation of disulphide bridges. The resulting derivative was co-polymerized with keyhole limpet haemocyanin. Two Macaca fascicularis monkeys were immunized with this conjugate. The monkeys were challenged,under anaesthesia,with a potentially lethal dose of male A.robustus crude venom. Both monkeys showed some minor symptoms of intoxication but recovered fully with no adverse after-effects. Immunization with the same immunogen, in the absence of keyhole limpet haemocyanin, did not protect a third monkey. The N-terminal 23 amino acid peptide derived from the sequence of robustoxin was synthesized and conjugated with ovalbumin. A fourth monkey was immunized with this conjugate. However,it was not protected against challenge.The implications of these results for the preparation of synthetic peptide vaccines are discussed.

  13. Immunization with a synthetic robustoxin derivative lacking disulphide bridges protects against a potentially lethal challenge with funnel-web spider (Atrax robustus) venom

    Indian Academy of Sciences (India)

    Alfio Comis; Margaret Tyler; Ewan Mylecharane; Ian Spence; Merlin Howden

    2009-03-01

    The venom of male Atrax robustus spiders is potentially lethal to primates. These spiders have been responsible for a number of human deaths. Robustoxin is the lethal toxin in the venom. It is a highly cross-linked polypeptide that has 42 amino acid residues and four disulphide bridges. If these bridges are broken, the resulting polypeptide is nontoxic. Robustoxin was chemically synthesized with all of its eight cysteine residues protected with acetamidomethyl groups in order to avoid formation of disulphide bridges. The resulting derivative was co-polymerized with keyhole limpet haemocyanin. Two Macaca fascicularis monkeys were immunized with this conjugate. The monkeys were challenged, under anaesthesia, with a potentially lethal dose of male A. robustus crude venom. Both monkeys showed some minor symptoms of intoxication but recovered fully with no adverse after-effects. Immunization with the same immunogen, in the absence of keyhole limpet haemocyanin, did not protect a third monkey. The N-terminal 23 amino acid peptide derived from the sequence of robustoxin was synthesized and conjugated with ovalbumin. A fourth monkey was immunized with this conjugate. However, it was not protected against challenge. The implications of these results for the preparation of synthetic peptide vaccines are discussed.

  14. Parasites and diseases in marine copepods: Challenges for future mass-production of live feed for fish larva production

    DEFF Research Database (Denmark)

    Skovgaard, Alf

    Copepods are the natural food for many marine fish larvae, and the use of cultured copepods as life feed is, therefore, becoming increasingly important as more marine fish species are being produced in aquaculture. Large-scale cultivation of copepods may be challenged by diseases and parasites...

  15. Virus-Like Particle Vaccination Protects Nonhuman Primates from Lethal Aerosol Exposure with Marburgvirus (VLP Vaccination Protects Macaques against Aerosol Challenges

    Directory of Open Access Journals (Sweden)

    John M. Dye

    2016-04-01

    Full Text Available Marburg virus (MARV was the first filovirus to be identified following an outbreak of viral hemorrhagic fever disease in Marburg, Germany in 1967. Due to several factors inherent to filoviruses, they are considered a potential bioweapon that could be disseminated via an aerosol route. Previous studies demonstrated that MARV virus-like particles (VLPs containing the glycoprotein (GP, matrix protein VP40 and nucleoprotein (NP generated using a baculovirus/insect cell expression system could protect macaques from subcutaneous (SQ challenge with multiple species of marburgviruses. In the current study, the protective efficacy of the MARV VLPs in conjunction with two different adjuvants: QS-21, a saponin derivative, and poly I:C against homologous aerosol challenge was assessed in cynomolgus macaques. Antibody responses against the GP antigen were equivalent in all groups receiving MARV VLPs irrespective of the adjuvant; adjuvant only-vaccinated macaques did not demonstrate appreciable antibody responses. All macaques were subsequently challenged with lethal doses of MARV via aerosol or SQ as a positive control. All MARV VLP-vaccinated macaques survived either aerosol or SQ challenge while animals administered adjuvant only exhibited clinical signs and lesions consistent with MARV disease and were euthanized after meeting the predetermined criteria. Therefore, MARV VLPs induce IgG antibodies recognizing MARV GP and VP40 and protect cynomolgus macaques from an otherwise lethal aerosol exposure with MARV.

  16. Virus-Like Particle Vaccination Protects Nonhuman Primates from Lethal Aerosol Exposure with Marburgvirus (VLP Vaccination Protects Macaques against Aerosol Challenges).

    Science.gov (United States)

    Dye, John M; Warfield, Kelly L; Wells, Jay B; Unfer, Robert C; Shulenin, Sergey; Vu, Hong; Nichols, Donald K; Aman, M Javad; Bavari, Sina

    2016-04-08

    Marburg virus (MARV) was the first filovirus to be identified following an outbreak of viral hemorrhagic fever disease in Marburg, Germany in 1967. Due to several factors inherent to filoviruses, they are considered a potential bioweapon that could be disseminated via an aerosol route. Previous studies demonstrated that MARV virus-like particles (VLPs) containing the glycoprotein (GP), matrix protein VP40 and nucleoprotein (NP) generated using a baculovirus/insect cell expression system could protect macaques from subcutaneous (SQ) challenge with multiple species of marburgviruses. In the current study, the protective efficacy of the MARV VLPs in conjunction with two different adjuvants: QS-21, a saponin derivative, and poly I:C against homologous aerosol challenge was assessed in cynomolgus macaques. Antibody responses against the GP antigen were equivalent in all groups receiving MARV VLPs irrespective of the adjuvant; adjuvant only-vaccinated macaques did not demonstrate appreciable antibody responses. All macaques were subsequently challenged with lethal doses of MARV via aerosol or SQ as a positive control. All MARV VLP-vaccinated macaques survived either aerosol or SQ challenge while animals administered adjuvant only exhibited clinical signs and lesions consistent with MARV disease and were euthanized after meeting the predetermined criteria. Therefore, MARV VLPs induce IgG antibodies recognizing MARV GP and VP40 and protect cynomolgus macaques from an otherwise lethal aerosol exposure with MARV.

  17. Protective efficacy of an H5N1 DNA vaccine against challenge with a lethal H5N1 virus in quail.

    Science.gov (United States)

    Li, Junping; Jiang, Yongping; Zhao, Shuangcheng; Chang, Xiaofei; Liu, Jinxiong; Zeng, Xianying; Li, Yanbing; Chen, Hualan

    2012-12-01

    Some H5N1 avian influenza viruses (AIVs) are lethal to quail; however, the use of inactivated vaccines in these birds is largely restricted because of side effects caused by oil adjuvants. Here we evaluated the protective efficacy of a DNA vaccine against lethal challenge with H5N1 highly pathogenic avian influenza virus (HPAIV) in quail. Groups of ten 3-wk-old quail were intramuscularly inoculated three times at 3-wk intervals with 10, 15, 30, or 60 microg, respectively, of plasmid pCAGGoptiHA, which expresses a codon-optimized hemagglutinin gene of the H5N1 virus A/goose/Guangdong/1/96 (GS/GD/96). The control group was inoculated with phosphate-buffered saline. Hemagglutination-inhibition (HI) antibodies were monitored every week after the primary vaccination. The quail were challenged intranasally with 10(5) EID50 of heterologous HPAIV A/duck/Fujian/31/2007 (DK/ FJ/31) (H5N1) 2 wk after the third inoculation. Oropharyngeal and cloacal swab specimens were collected 3, 5, and 7 days after inoculation, and quail were observed daily for disease signs and death for 2 wk. The quail showed no side effects after the plasmid inoculation, and HI antibodies were detectable 1 wk after the second vaccination in all groups and increased sharply after the third inoculation. All quail in the PBS-inoculated group and 20% of the birds in the 10 microg plasmid-inoculated group died after the lethal H5N1 virus challenge; however, birds in the 15, 30, and 60 jg plasmid-inoculated groups were completely protected. These results indicate that this DNA vaccine holds promise for use in quail to protect against H5N1 AIV.

  18. A cytomegalovirus-based vaccine provides long-lasting protection against lethal Ebola virus challenge after a single dose.

    Science.gov (United States)

    Tsuda, Yoshimi; Parkins, Christopher J; Caposio, Patrizia; Feldmann, Friederike; Botto, Sara; Ball, Susan; Messaoudi, Ilhem; Cicin-Sain, Luka; Feldmann, Heinz; Jarvis, Michael A

    2015-05-01

    Ebola virus (Zaire ebolavirus; EBOV) is a highly lethal hemorrhagic disease virus that most recently was responsible for two independent 2014 outbreaks in multiple countries in Western Africa, and the Democratic Republic of the Congo, respectively. Herein, we show that a cytomegalovirus (CMV)-based vaccine provides durable protective immunity from Ebola virus following a single vaccine dose. This study has implications for human vaccination against ebolaviruses, as well as for development of a 'disseminating' vaccine to target these viruses in wild African great apes.

  19. A rabies vaccine adjuvanted with saponins from leaves of the soap tree (Quillaja brasiliensis) induces specific immune responses and protects against lethal challenge.

    Science.gov (United States)

    Yendo, Anna Carolina A; de Costa, Fernanda; Cibulski, Samuel P; Teixeira, Thais F; Colling, Luana C; Mastrogiovanni, Mauricio; Soulé, Silvia; Roehe, Paulo M; Gosmann, Grace; Ferreira, Fernando A; Fett-Neto, Arthur G

    2016-04-29

    Quillaja brasiliensis (Quillajaceae) is a saponin producing species native from southern Brazil and Uruguay. Its saponins are remarkably similar to those of Q. saponaria, which provides most of the saponins used as immunoadjuvants in vaccines. The immunostimulating capacities of aqueous extract (AE) and purified saponin fraction (QB-90) obtained from leaves of Q. brasiliensis were favorably comparable to those of a commercial saponin-based adjuvant preparation (Quil-A) in experimental vaccines against bovine herpesvirus type 1 and 5, poliovirus and bovine viral diarrhea virus in mice model. Herein, the immunogenicity and protection efficacy of rabies vaccines adjuvanted with Q. brasiliensis AE and its saponin fractions were compared with vaccines adjuvanted with either commercial Quil-A or Alum. Mice were vaccinated with one or two doses (on days 0 and 14) of one of the different vaccines and serum levels of total IgG, IgG1 and IgG2a were quantified over time. A challenge experiment with a lethal dose of rabies virus was carried out with the formulations. Viral RNA detection in the brain of mice was performed by qPCR, and RNA copy-numbers were quantified using a standard curve of in vitro transcribed RNA. All Q. brasiliensis saponin-adjuvanted vaccines significantly enhanced levels of specific IgG isotypes when compared with the no adjuvant group (P ≤ 0.05). Overall, one or two doses of saponin-based vaccine were efficient to protect against the lethal rabies exposure. Both AE and saponin fractions from Q. brasiliensis leaves proved potent immunological adjuvants in vaccines against a lethal challenge with a major livestock pathogen, hence confirming their value as competitive or complementary sustainable alternatives to saponins of Q. saponaria.

  20. Characterization of Immune Responses Induced by Ebola Virus Glycoprotein (GP) and Truncated GP Isoform DNA Vaccines and Protection Against Lethal Ebola Virus Challenge in Mice

    Science.gov (United States)

    Li, Wenfang; Ye, Ling; Carrion, Ricardo; Mohan, Gopi S.; Nunneley, Jerritt; Staples, Hilary; Ticer, Anysha; Patterson, Jean L.; Compans, Richard W.; Yang, Chinglai

    2015-01-01

    In addition to its surface glycoprotein (GP), Ebola virus directs the production of large quantities of a truncated glycoprotein isoform (sGP) that is secreted into the extracellular space. We recently reported that sGP actively diverts host antibody responses against the epitopes that it shares with GP and thereby allows itself to absorb anti-GP antibodies, a phenomenon we termed “antigenic subversion.” To investigate the effect of antigenic subversion by sGP on protection against virus infection, we compared immune responses induced by different prime-boost immunization regimens with GP and sGP DNA vaccines in mice and their efficacy against lethal Ebola virus challenge. Similar levels of anti-GP antibodies were induced by 2 immunizations with sGP and GP DNA vaccines. However, 2 immunizations with GP but not sGP DNA vaccine fully protected mice from lethal challenge. Boosting with sGP or GP DNA vaccine in mice that had been primed by GP or sGP DNA vaccine augmented the levels of anti-GP antibody responses and further improved protective efficacy against Ebola virus infection. These results show that both the quality and the levels of anti-GP antibody responses affect the efficacy of protection against Ebola virus infection. PMID:25877553

  1. Amino Acid Substitutions Improve the Immunogenicity of H7N7HA Protein and Protect Mice against Lethal H7N7 Viral Challenge.

    Directory of Open Access Journals (Sweden)

    Subaschandrabose Rajesh Kumar

    Full Text Available Avian influenza A H7N7/NL/219/03 virus creates a serious pandemic threat to human health because it can transmit directly from domestic poultry to humans and from human to human. Our previous vaccine study reported that mice when immunized intranasally (i.n with live Bac-HA were protected from lethal H7N7/NL/219/03 challenge, whereas incomplete protection was obtained when administered subcutaneously (s.c due to the fact that H7N7 is a poor inducer of neutralizing antibodies. Interestingly, our recent vaccine studies reported that mice when vaccinated subcutaneously with Bac-HA (H7N9 was protected against both H7N9 (A/Sh2/2013 and H7N7 virus challenge. HA1 region of both H7N7 and H7N9 viruses are differ at 15 amino acid positions. Among those, we selected three amino acid positions (T143, T198 and I211 in HA1 region of H7N7. These amino acids are located within or near the receptor binding site. Following the selection, we substituted the amino acid at these three positions with amino acids found on H7N9HA wild-type. In this study, we evaluate the impact of amino acid substitutions in the H7N7 HA-protein on the immunogenicity. We generated six mutant constructs from wild-type influenza H7N7HA cDNA by site directed mutagenesis, and individually expressed mutant HA protein on the surface of baculovirus (Bac-HAm and compared their protective efficacy of the vaccines with Bac-H7N7HA wild-type (Bac-HA by lethal H7N7 viral challenge in a mouse model. We found that mice immunized subcutaneously with Bac-HAm constructs T143A or T198A-I211V or I211V-T143A serum showed significantly higher hemagglutination inhibition and neutralization titer against H7N7 and H7N9 viruses when compared to Bac-HA vaccinated mice groups. We also observed low level of lung viral titer, negligible weight loss and complete protection against lethal H7N7 viral challenge. Our results indicated that amino acid substitution at position 143 or 211 improve immunogenicity of H7N7HA

  2. Immunization with Cytomegalovirus Envelope Glycoprotein M and Glycoprotein N DNA Vaccines can Provide Mice with Complete Protection against a Lethal Murine Cytomegalovirus Challenge

    Institute of Scientific and Technical Information of China (English)

    Huadong Wang; Yanfeng Yao; Chaoyang Huang; Quanjiao Chen; Jianjun Chen; Ze Chen

    2013-01-01

    Human cytomegalovirus virions contain three major glycoprotein complexes (gC Ⅰ,Ⅱ,Ⅲ),all of which are required for CMV infectivity.These complexes also represent major antigenic targets for anti-viral immune responses.The gC Ⅱ complex consists of two glycoproteins,gM and gN.In the current study,DNA vaccines expressing the murine cytomegalovirus (MCMV) homologs of the gM and gN proteins were evaluated for protection against lethal MCMV infection in a mouse model.Humoral and cellular immune responses,spleen viral titers,and mice survival and body-weight changes were examined.The results showed that immunization with gM or gN DNA vaccine alone was not able to offer good protection,whereas co-immunization with both gM and gN induced an effective neutralizing antibody response and cellular immune response,and provided mice with complete protection against a lethal MCMV challenge.This study provides the first in vivo evidence that the gC Ⅱ (gM-gN) complex may be able to serve as a protective subunit antigen for future HCMV vaccine development.

  3. A recombinant measles vaccine expressing chikungunya virus-like particles is strongly immunogenic and protects mice from lethal challenge with chikungunya virus.

    Science.gov (United States)

    Brandler, Samantha; Ruffié, Claude; Combredet, Chantal; Brault, Jean-Baptiste; Najburg, Valérie; Prevost, Marie-Christine; Habel, André; Tauber, Erich; Desprès, Philippe; Tangy, Frédéric

    2013-08-12

    Chikungunya virus (CHIKV), a mosquito-transmitted alphavirus, recently reemerged in the Indian Ocean, India and Southeast Asia, causing millions of cases of severe polyarthralgia. No specific treatment to prevent disease or vaccine to limit epidemics is currently available. Here we describe a recombinant live-attenuated measles vaccine (MV) expressing CHIKV virus-like particles comprising capsid and envelope structural proteins from the recent CHIKV strain La Reunion. Immunization of mice susceptible to measles virus induced high titers of CHIKV antibodies that neutralized several primary isolates. Specific cellular immune responses were also elicited. A single immunization with this vaccine candidate protected all mice from a lethal CHIKV challenge, and passive transfer of immune sera conferred protection to naïve mice. Measles vaccine is one of the safest and most effective human vaccines. A recombinant MV-CHIKV virus could make a safe and effective vaccine against chikungunya that deserves to be further tested in human trials.

  4. A baculovirus dual expression system-based vaccine confers complete protection against lethal challenge with H9N2 avian influenza virus in mice

    Directory of Open Access Journals (Sweden)

    Ye Yu

    2011-06-01

    Full Text Available Abstract Background Avian influenza viruses of H9N2 subtype have become highly prevalent in avian species. Although these viruses generally cause only mild to moderate disease, they can infect a wide variety of species, including chickens, quail, turkeys, ducks, geese, pheasant, partridge, and pigeon, even transmitted to mammalian species, including humans, accelerating the efforts to devise protective strategies against them. Results The results showed that stronger immune responses were induced in a mouse model immunized with BV-Dual-HA than in those vaccinated with a DNA vaccine encoding the same antigen. Moreover, complete protection against lethal challenge with H9N2 virus was observed in mice. Conclusion BV-Dual-HA could be utilized as a vaccine candidate against H9N2 virus infection.

  5. An adjuvanted inactivated murine cytomegalovirus (MCMV) vaccine induces potent and long-term protective immunity against a lethal challenge with virulent MCMV

    Science.gov (United States)

    2014-01-01

    Background Human cytomegalovirus (HCMV) is a ubiquitous pathogen that causes serious problems in immunocompromised or immunologically immature hosts. Vaccination is the preferred approach for prevention of HCMV infection, but so far no approved HCMV vaccine is available. In this study, we assessed the immunogenicity and protective immunity of a formalin-inactivated murine cytomegalovirus vaccine (FI-MCMV) in a mouse model in combination with adjuvants MF59, alum, or chitosan. Methods Specific-pathogen-free BALB/c mice aged 6–8 weeks were immunized twice, 3 weeks apart, with various doses of FI-MCMV (0.25 μg, 1 μg, 4 μg) with or without adjuvant. Mice were challenged with a lethal dose (5 × LD50) of a more virulent mouse salivary gland-passaged MCMV 3 weeks after the second immunization. The protective immunity of the vaccine was evaluated by determining the survival rates, residual spleen and salivary gland viral loads, body weight changes, and serum anti-MCMV IgG titers. Results Immunization with FI-MCMV vaccine induced a high level of specific antibody response. Antigen sparing was achieved by the addition of an adjuvant, which significantly enhanced the humoral response to vaccine antigens with a wide range of doses. The level of live virus detected in the spleen on day 5 and in the salivary glands on day 21 after the lethal challenge was significantly lower in adjuvant-treated groups than in controls. Survival rates in adjuvant-treated groups also increased significantly. Furthermore, these protective immune responses were sustained for at least 6 months following immunization. Conclusions These results show that inactivated MCMV vaccine is effective, and that the adjuvanted FI-MCMV vaccine provides more effective and longer-term protection than the adjuvant-free vaccine. PMID:24720840

  6. Incorporation of membrane-bound, mammalian-derived immunomodulatory proteins into influenza whole virus vaccines boosts immunogenicity and protection against lethal challenge

    Directory of Open Access Journals (Sweden)

    Roberts Paul C

    2009-04-01

    Full Text Available Abstract Background Influenza epidemics continue to cause morbidity and mortality within the human population despite widespread vaccination efforts. This, along with the ominous threat of an avian influenza pandemic (H5N1, demonstrates the need for a much improved, more sophisticated influenza vaccine. We have developed an in vitro model system for producing a membrane-bound Cytokine-bearing Influenza Vaccine (CYT-IVAC. Numerous cytokines are involved in directing both innate and adaptive immunity and it is our goal to utilize the properties of individual cytokines and other immunomodulatory proteins to create a more immunogenic vaccine. Results We have evaluated the immunogenicity of inactivated cytokine-bearing influenza vaccines using a mouse model of lethal influenza virus challenge. CYT-IVACs were produced by stably transfecting MDCK cell lines with mouse-derived cytokines (GM-CSF, IL-2 and IL-4 fused to the membrane-anchoring domain of the viral hemagglutinin. Influenza virus replication in these cell lines resulted in the uptake of the bioactive membrane-bound cytokines during virus budding and release. In vivo efficacy studies revealed that a single low dose of IL-2 or IL-4-bearing CYT-IVAC is superior at providing protection against lethal influenza challenge in a mouse model and provides a more balanced Th1/Th2 humoral immune response, similar to live virus infections. Conclusion We have validated the protective efficacy of CYT-IVACs in a mammalian model of influenza virus infection. This technology has broad applications in current influenza virus vaccine development and may prove particularly useful in boosting immune responses in the elderly, where current vaccines are minimally effective.

  7. Role of the DNA Sensor STING in Protection from Lethal Infection following Corneal and Intracerebral Challenge with Herpes Simplex Virus 1.

    Science.gov (United States)

    Parker, Zachary M; Murphy, Aisling A; Leib, David A

    2015-11-01

    STING is a protein in the cytosolic DNA and cyclic dinucleotide sensor pathway that is critical for the initiation of innate responses to infection by various pathogens. Consistent with this, herpes simplex virus 1 (HSV-1) causes invariable and rapid lethality in STING-deficient (STING(-/-)) mice following intravenous (i.v.) infection. In this study, using real-time bioluminescence imaging and virological assays, as expected, we demonstrated that STING(-/-) mice support greater replication and spread in ocular tissues and the nervous system. In contrast, they did not succumb to challenge via the corneal route even with high titers of a virus that was routinely lethal to STING(-/-) mice by the i.v. route. Corneally infected STING(-/-) mice also showed increased periocular disease and increased corneal and trigeminal ganglia titers, although there was no difference in brain titers. They also showed elevated expression of tumor necrosis factor alpha (TNF-α) and CXCL9 relative to control mice but surprisingly modest changes in type I interferon expression. Finally, we also showed that HSV strains lacking the ability to counter autophagy and the PKR-driven antiviral state had near-wild-type virulence following intracerebral infection of STING(-/-) mice. Together, these data show that while STING is an important component of host resistance to HSV in the cornea, its previously shown immutable role in mediating host survival by the i.v. route was not recapitulated following a mucosal infection route. Furthermore, our data are consistent with the idea that HSV counters STING-mediated induction of the antiviral state and autophagy response, both of which are critical factors for survival following direct infection of the nervous system. HSV infections represent an incurable source of morbidity and mortality in humans and are especially severe in neonatal and immunocompromised populations. A key step in the development of an immune response is the recognition of microbial

  8. Protection against lethal subcutaneous challenge of virulent Y. pestis strain 141 using an F1-V subunit vaccine

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In this study, we designed and engineered a two-component recombinant fusion protein antigen as a vaccine candidate against the possible biological threat of Yersinia pestis. The recombinant F1-V protein was formulated with Alhydrogel. A four-time injection with a dosage of 10, 20 and 50 μg/mouse in about two months was adopted for vaccination. Serum antibodies and subclass of T helper cells were measured and analyzed. After the final vaccination, the mice were challenged by 141 strain with 25―600 LD50. In conclusion, the recombinant vaccine was capable of inducing protective immunity against subcutaneous challenge. The level of serum IgG was supposed to be a main factor that affected the final protection of challenge. 20 μg recombinant protein could induce an endpoint titre of serum IgG as high as 51200, which was enough to afford 100% protection against 400 LD50 virulent 141 challenge. The antibody isotype analysis showed that the vaccine induced predominantly an IgG1 rather than IgG2a response. Flow cytometric analysis revealed that Alhydrogel significantly helped induce a stronger humoral immunity instead of CTL cellular response. These findings suggested that the plague F1-V subunit vaccine is promising for the next plague vaccine.

  9. Sensor detection of parasite eggs and (oo-)cysts - possibilities and challenges

    DEFF Research Database (Denmark)

    Enemark, Heidi

    2015-01-01

    -time sensor detection of Cryptosporidium and Giardia in drinking water. This novel optical technique, in combination with advanced data analysis, yields a measure for the protozoal content present in a sample. High sensitivity of the system is acquired through a combination of a new, patented filtration......To secure the safety and quality of food and water presence of pathogens including parasites must be controlled. This relies among other things on implementation of sensitive and specific tests which are able to rule out the occurrence of parasites. Worldwide environmentally resistant oocysts...... use of a metallic filter, sonication and "air backwash" are key factors in the creation of this highly efficient and robust system which can be used continuously for extended time with minimal maintenance requirements. Sample acquisition and analysis is performed in real-time where objects...

  10. Protection of mice against lethal challenge with 2009 H1N1 influenza A virus by 1918-like and classical swine H1N1 based vaccines.

    Directory of Open Access Journals (Sweden)

    Balaji Manicassamy

    2010-01-01

    Full Text Available The recent 2009 pandemic H1N1 virus infection in humans has resulted in nearly 5,000 deaths worldwide. Early epidemiological findings indicated a low level of infection in the older population (>65 years with the pandemic virus, and a greater susceptibility in people younger than 35 years of age, a phenomenon correlated with the presence of cross-reactive immunity in the older population. It is unclear what virus(es might be responsible for this apparent cross-protection against the 2009 pandemic H1N1 virus. We describe a mouse lethal challenge model for the 2009 pandemic H1N1 strain, used together with a panel of inactivated H1N1 virus vaccines and hemagglutinin (HA monoclonal antibodies to dissect the possible humoral antigenic determinants of pre-existing immunity against this virus in the human population. By hemagglutinination inhibition (HI assays and vaccination/challenge studies, we demonstrate that the 2009 pandemic H1N1 virus is antigenically similar to human H1N1 viruses that circulated from 1918-1943 and to classical swine H1N1 viruses. Antibodies elicited against 1918-like or classical swine H1N1 vaccines completely protect C57B/6 mice from lethal challenge with the influenza A/Netherlands/602/2009 virus isolate. In contrast, contemporary H1N1 vaccines afforded only partial protection. Passive immunization with cross-reactive monoclonal antibodies (mAbs raised against either 1918 or A/California/04/2009 HA proteins offered full protection from death. Analysis of mAb antibody escape mutants, generated by selection of 2009 H1N1 virus with these mAbs, indicate that antigenic site Sa is one of the conserved cross-protective epitopes. Our findings in mice agree with serological data showing high prevalence of 2009 H1N1 cross-reactive antibodies only in the older population, indicating that prior infection with 1918-like viruses or vaccination against the 1976 swine H1N1 virus in the USA are likely to provide protection against the 2009

  11. CD4 and CD8 T cells mediate distinct lethal meningoencephalitis in mice challenged with Tacaribe arenavirus

    Science.gov (United States)

    Ireland, Derek DC; Tami, Cecilia; Pedras-Vasconcelos, Joao; Verthelyi, Daniela

    2017-01-01

    Neonates are at increased risk of viral encephalopathies that can result in neurological dysfunction, seizures, permanent disability and even death. The neurological damage results from the combined effect of the virus and the immune response it elicits, thus finding tools to facilitate viral clearance from central nervous system (CNS) while minimizing neuron damage remains a critical challenge. Neonatal mice inoculated intraperitoneally with Tacaribe virus (TCRV) develop seizures, hindlimb paralysis and death within 15 days of inoculation. TCRV localizes to the CNS within days of challenge, primarily infecting astrocytes in the cerebellum and brain stem. We show that infection leads to inflammation, T cell and monocyte infiltration into the cerebellar parenchyma, apoptosis of astrocytes, neuronal degeneration and loss of Purkinje cells. Infiltrating antigen-specific T cells fail to clear the virus but drive the disease, as T-cell-deficient CD3ɛ KO mice survive TCRV infection with minimal inflammation or clinical manifestations despite no difference in CNS viral loads in comparison with T-cell sufficient mice. CD8+ T cells drive the pathology, which even in the absence of CD4+ T-cell help, infiltrate the parenchyma and mediate the apoptotic loss of cerebellar astrocytes, neurodegeneration and loss of Purkinje cells resulting in loss of balance, paralysis and death. CD4+ T cells are also pathogenic inducing gliosis and inflammation in the cerebellum and cerebrum that are associated with wasting and death several weeks after CD4+ T-cell transfer. These data demonstrate distinct pathogenic effects of CD4+ and CD8+ T cells and identify them as possible therapeutic targets. PMID:27569560

  12. Knockout of the dhfr-ts gene in Trypanosoma cruzi generates attenuated parasites able to confer protection against a virulent challenge.

    Directory of Open Access Journals (Sweden)

    Cecilia Perez Brandan

    2011-12-01

    Full Text Available BACKGROUND: Trypanosoma cruzi is a protozoan parasite that causes severe disease in millions of habitants of developing countries. Currently there is no vaccine to prevent this disease and the available drugs have the consequences of side effects. Live vaccines are likely to be more effective in inducing protection than recombinant proteins or DNA vaccines; however, safety problems associated to their use have been pointed out. In recent years, increasing knowledge on the molecular genetics of Trypanosomes has allowed the identification and elimination of genes that may be necessary for parasite infectivity and survival. In this sense, targeted deletion or disruption of specific genes in the parasite genome may protect against such reversion to virulent genotypes. METHODS AND FINDINGS: By targeted gene disruption we generated monoallelic mutant parasites for the dhfr-ts gene in a T. cruzi strain that has been shown to be naturally attenuated. In comparison to T. cruzi wild type epimastigotes, impairment in growth of dhfr-ts(+/- mutant parasites was observed and mutant clones displayed decreased virulence in mice. Also, a lower number of T. cruzi-specific CD8(+ T cells, in comparison to those induced by wild type parasites, was detected in mice infected with mutant parasites. However, no remarkable differences in the protective effect of TCC wild type versus TCC mutant parasites were observed. Mice challenged with virulent parasites a year after the original infection with the mutant parasites still displayed a significant control over the secondary infection. CONCLUSION: This study indicates that it is possible to generate genetically attenuated T. cruzi parasites able to confer protection against further T. cruzi infections.

  13. An M2e-based multiple antigenic peptide vaccine protects mice from lethal challenge with divergent H5N1 influenza viruses

    Directory of Open Access Journals (Sweden)

    Chan Chris CS

    2010-01-01

    Full Text Available Abstract Background A growing concern has raised regarding the pandemic potential of the highly pathogenic avian influenza (HPAI H5N1 viruses. Consequently, there is an urgent need to develop an effective and safe vaccine against the divergent H5N1 influenza viruses. In the present study, we designed a tetra-branched multiple antigenic peptide (MAP-based vaccine, designated M2e-MAP, which contains the sequence overlapping the highly conserved extracellular domain of matrix protein 2 (M2e of a HPAI H5N1 virus, and investigated its immune responses and cross-protection against different clades of H5N1 viruses. Results Our results showed that M2e-MAP vaccine induced strong M2e-specific IgG antibody responses following 3-dose immunization of mice with M2e-MAP in the presence of Freunds' or aluminium (alum adjuvant. M2e-MAP vaccination limited viral replication and attenuated histopathological damage in the challenged mouse lungs. The M2e-MAP-based vaccine protected immunized mice against both clade1: VN/1194 and clade2.3.4: SZ/406H H5N1 virus challenge, being able to counteract weight lost and elevate survival rate following lethal challenge of H5N1 viruses. Conclusions These results suggest that M2e-MAP presenting M2e of H5N1 virus has a great potential to be developed into an effective subunit vaccine for the prevention of infection by a broad spectrum of HPAI H5N1 viruses.

  14. A recombinant Hendra virus G glycoprotein-based subunit vaccine protects ferrets from lethal Hendra virus challenge.

    Science.gov (United States)

    Pallister, Jackie; Middleton, Deborah; Wang, Lin-Fa; Klein, Reuben; Haining, Jessica; Robinson, Rachel; Yamada, Manabu; White, John; Payne, Jean; Feng, Yan-Ru; Chan, Yee-Peng; Broder, Christopher C

    2011-08-01

    The henipaviruses, Hendra virus (HeV) and Nipah virus (NiV), are two deadly zoonotic viruses for which no vaccines or therapeutics have yet been approved for human or livestock use. In 14 outbreaks since 1994 HeV has been responsible for multiple fatalities in horses and humans, with all known human infections resulting from close contact with infected horses. A vaccine that prevents virus shedding in infected horses could interrupt the chain of transmission to humans and therefore prevent HeV disease in both. Here we characterise HeV infection in a ferret model and show that it closely mirrors the disease seen in humans and horses with induction of systemic vasculitis, including involvement of the pulmonary and central nervous systems. This model of HeV infection in the ferret was used to assess the immunogenicity and protective efficacy of a subunit vaccine based on a recombinant soluble version of the HeV attachment glycoprotein G (HeVsG), adjuvanted with CpG. We report that ferrets vaccinated with a 100 μg, 20 μg or 4 μg dose of HeVsG remained free of clinical signs of HeV infection following a challenge with 5000 TCID₅₀ of HeV. In addition, and of considerable importance, no evidence of virus or viral genome was detected in any tissues or body fluids in any ferret in the 100 and 20 μg groups, while genome was detected in the nasal washes only of one animal in the 4 μg group. Together, our findings indicate that 100 μg or 20 μg doses of HeVsG vaccine can completely prevent a productive HeV infection in the ferret, suggesting that vaccination to prevent the infection and shedding of HeV is possible.

  15. Involvement of CD8+ T cell-mediated immune responses in LcrV DNA vaccine induced protection against lethal Yersinia pestis challenge.

    Science.gov (United States)

    Wang, Shixia; Goguen, Jon D; Li, Fusheng; Lu, Shan

    2011-09-09

    Yersinia pestis (Y. pestis) is the causative pathogen of plague, a highly fatal disease for which an effective vaccine, especially against mucosal transmission, is still not available. Like many bacterial infections, antigen-specific antibody responses have been traditionally considered critical, if not solely responsible, for vaccine-induced protection against Y. pestis. Studies in recent years have suggested the importance of T cell immune responses against Y. pestis infection but information is still limited about the details of Y. pestis antigen-specific T cell immune responses. In current report, studies are conducted to identify the presence of CD8+ T cell epitopes in LcrV protein, the leading antigen of plague vaccine development. Furthermore, depletion of CD8+ T cells in LcrV DNA vaccinated Balb/C mice led to reduced protection against lethal intranasal challenge of Y. pestis. These findings establish that an LcrV DNA vaccine is able to elicit CD8+ T cell immune responses against specific epitopes of this key plague antigen and that a CD8+ T cell immune response is involved in LcrV DNA vaccine-elicited protection. Future studies in plague vaccine development will need to examine if the presence of detectable T cell immune responses, in particular CD8+ T-cell immune responses, will enhance the protection against Y. pestis in higher animal species or humans. Copyright © 2010 Elsevier Ltd. All rights reserved.

  16. The effect of parasites on wildlife

    NARCIS (Netherlands)

    Borgsteede, F.H.M.

    1996-01-01

    Populations of animals which live in the wild are regulated by many biotic and abiotic factors. Parasites are one of the biotic factors. Parasites may influence their hosts in different ways. They may cause the death of the host due to a direct lethal effect or an indirect effect. Direct lethal effe

  17. The effect of parasites on wildlife

    NARCIS (Netherlands)

    Borgsteede, F.H.M.

    1996-01-01

    Populations of animals which live in the wild are regulated by many biotic and abiotic factors. Parasites are one of the biotic factors. Parasites may influence their hosts in different ways. They may cause the death of the host due to a direct lethal effect or an indirect effect. Direct lethal effe

  18. Influenza virus-like particles produced by transient expression in Nicotiana benthamiana induce a protective immune response against a lethal viral challenge in mice.

    Science.gov (United States)

    D'Aoust, Marc-André; Lavoie, Pierre-Olivier; Couture, Manon M-J; Trépanier, Sonia; Guay, Jean-Martin; Dargis, Michèle; Mongrand, Sébastien; Landry, Nathalie; Ward, Brian J; Vézina, Louis-P

    2008-12-01

    A strain-specific vaccine represents the best possible response to the threat of an influenza pandemic. Rapid delivery of such a vaccine to the world's population before the peak of the first infection wave seems to be an unattainable goal with the current influenza vaccine manufacturing capacity. Plant-based transient expression is one of the few production systems that can meet the anticipated surge requirement. To assess the capability of plant agroinfiltration to produce an influenza vaccine, we expressed haemagglutinin (HA) from strains A/Indonesia/5/05 (H5N1) and A/New Caledonia/20/99 (H1N1) by agroinfiltration of Nicotiana benthamiana plants. Size distribution analysis of protein content in infiltrated leaves revealed that HA was predominantly assembled into high-molecular-weight structures. H5-containing structures were purified and examination by transmission electron microscopy confirmed virus-like particle (VLP) assembly. High-performance thin layer chromatography analysis of VLP lipid composition highlighted polar and neutral lipid contents comparable with those of purified plasma membranes from tobacco plants. Electron microscopy of VLP-producing cells in N. benthamiana leaves confirmed that VLPs accumulated in apoplastic indentations of the plasma membrane. Finally, immunization of mice with two doses of as little as 0.1 microg of purified influenza H5-VLPs triggered a strong immune response against the homologous virus, whereas two doses of 0.5 microg of H5-VLPs conferred complete protection against a lethal challenge with the heterologous A/Vietnam/1194/04 (H5N1) strain. These results show, for the first time, that plants are capable of producing enveloped influenza VLPs budding from the plasma membrane; such VLPs represent very promising candidates for vaccination against influenza pandemic strains.

  19. Preventive chemotherapy as a strategy for elimination of neglected tropical parasitic diseases: endgame challenges.

    Science.gov (United States)

    Bockarie, Moses J; Kelly-Hope, Louise A; Rebollo, Maria; Molyneux, David H

    2013-08-05

    Global efforts to address neglected tropical diseases (NTDs) were stimulated in January 2012 by the London declaration at which 22 partners, including the Bill & Melinda Gates Foundation, World Bank, World Health Organization (WHO) and major pharmaceutical companies committed to sustaining and expanding NTD programmes to eliminate or eradicate 11 NTDs by 2020 to achieve the goals outlined in the recently published WHO road map. Here, we present the current context of preventive chemotherapy for some NTDs, and discuss the problems faced by programmes as they consider the 'endgame', such as difficulties of access to populations in post-conflict settings, limited human and financial resources, and the need to expand access to clean water and improved sanitation for schistosomiasis and soil-transmitted helminthiasis. In the case of onchocerciasis and lymphatic filariasis, ivermectin treatment carries a significant risk owing to serious adverse effects in some patients co-infected with the tropical eye worm Loa loa filariasis. We discuss the challenges of managing complex partnerships, and maintain advocacy messages for the continued support for elimination of these preventable diseases.

  20. Targeting the non-structural protein 1 from dengue virus to a dendritic cell population confers protective immunity to lethal virus challenge.

    Science.gov (United States)

    Henriques, Hugo R; Rampazo, Eline V; Gonçalves, Antonio J S; Vicentin, Elaine C M; Amorim, Jaime H; Panatieri, Raquel H; Amorim, Kelly N S; Yamamoto, Marcio M; Ferreira, Luís C S; Alves, Ada M B; Boscardin, Silvia B

    2013-01-01

    Dengue is the most prevalent arboviral infection, affecting millions of people every year. Attempts to control such infection are being made, and the development of a vaccine is a World Health Organization priority. Among the proteins being tested as vaccine candidates in preclinical settings is the non-structural protein 1 (NS1). In the present study, we tested the immune responses generated by targeting the NS1 protein to two different dendritic cell populations. Dendritic cells (DCs) are important antigen presenting cells, and targeting proteins to maturing DCs has proved to be an efficient means of immunization. Antigen targeting is accomplished by the use of a monoclonal antibody (mAb) directed against a DC cell surface receptor fused to the protein of interest. We used two mAbs (αDEC205 and αDCIR2) to target two distinct DC populations, expressing either DEC205 or DCIR2 endocytic receptors, respectively, in mice. The fusion mAbs were successfully produced, bound to their respective receptors, and were used to immunize BALB/c mice in the presence of polyriboinosinic: polyribocytidylic acid (poly (I:C)), as a DC maturation stimulus. We observed induction of strong anti-NS1 antibody responses and similar antigen binding affinity irrespectively of the DC population targeted. Nevertheless, the IgG1/IgG2a ratios were different between mouse groups immunized with αDEC-NS1 and αDCIR2-NS1 mAbs. When we tested the induction of cellular immune responses, the number of IFN-γ producing cells was higher in αDEC-NS1 immunized animals. In addition, mice immunized with the αDEC-NS1 mAb were significantly protected from a lethal intracranial challenge with the DENV2 NGC strain when compared to mice immunized with αDCIR2-NS1 mAb. Protection was partially mediated by CD4(+) and CD8(+) T cells as depletion of these populations reduced both survival and morbidity signs. We conclude that targeting the NS1 protein to the DEC205(+) DC population with poly (I:C) opens

  1. Targeting the non-structural protein 1 from dengue virus to a dendritic cell population confers protective immunity to lethal virus challenge.

    Directory of Open Access Journals (Sweden)

    Hugo R Henriques

    Full Text Available Dengue is the most prevalent arboviral infection, affecting millions of people every year. Attempts to control such infection are being made, and the development of a vaccine is a World Health Organization priority. Among the proteins being tested as vaccine candidates in preclinical settings is the non-structural protein 1 (NS1. In the present study, we tested the immune responses generated by targeting the NS1 protein to two different dendritic cell populations. Dendritic cells (DCs are important antigen presenting cells, and targeting proteins to maturing DCs has proved to be an efficient means of immunization. Antigen targeting is accomplished by the use of a monoclonal antibody (mAb directed against a DC cell surface receptor fused to the protein of interest. We used two mAbs (αDEC205 and αDCIR2 to target two distinct DC populations, expressing either DEC205 or DCIR2 endocytic receptors, respectively, in mice. The fusion mAbs were successfully produced, bound to their respective receptors, and were used to immunize BALB/c mice in the presence of polyriboinosinic: polyribocytidylic acid (poly (I:C, as a DC maturation stimulus. We observed induction of strong anti-NS1 antibody responses and similar antigen binding affinity irrespectively of the DC population targeted. Nevertheless, the IgG1/IgG2a ratios were different between mouse groups immunized with αDEC-NS1 and αDCIR2-NS1 mAbs. When we tested the induction of cellular immune responses, the number of IFN-γ producing cells was higher in αDEC-NS1 immunized animals. In addition, mice immunized with the αDEC-NS1 mAb were significantly protected from a lethal intracranial challenge with the DENV2 NGC strain when compared to mice immunized with αDCIR2-NS1 mAb. Protection was partially mediated by CD4(+ and CD8(+ T cells as depletion of these populations reduced both survival and morbidity signs. We conclude that targeting the NS1 protein to the DEC205(+ DC population with poly (I

  2. The live attenuated Actinobacillus pleuropneumoniae triple-deletion mutant ΔapxIC ΔapxIIC ΔapxIV-ORF1 strain, SLW05, Immunizes pigs against lethal challenge with Haemophilus parasuis.

    Science.gov (United States)

    Fu, Shulin; Ou, Jiwen; Zhang, Minmin; Xu, Juan; Liu, Huazhen; Liu, Jinlin; Yuan, Fangyan; Chen, Huanchun; Bei, Weicheng

    2013-02-01

    Haemophilus parasuis and Actinobacillus pleuropneumoniae both belong to the family Pasteurellaceae and are major respiratory pathogens that cause large economic losses in the pig industry worldwide. We previously constructed an attenuated A. pleuropneumoniae serovar 1 live vaccine prototype, SLW05 (ΔapxIC ΔapxIIC ΔapxIV-ORF1), which is able to produce nontoxic but immunogenic ApxIA, ApxIIA, and ApxIVA. This triple-deletion mutant strain was shown to elicit protective immunity against virulent A. pleuropneumoniae. In the present study, we investigated whether immunization with SLW05 could also protect against lethal challenge with virulent H. parasuis SH0165 (serovar 5) or MD0322 (serovar 4). The SLW05 strain was found to elicit a strong humoral antibody response in pigs and to confer significant protection against challenge with a lethal dose of H. parasuis SH0165 or MD0322. IgG subtype analysis revealed that SLW05 induces a bias toward a Th1-type immune response and stimulates interleukin 2 (IL-2) and gamma interferon (IFN-γ) production. Moreover, antisera from SLW05-vaccinated pigs efficiently inhibited both A. pleuropneumoniae and H. parasuis growth in a whole-blood assay. This is the first report that a live attenuated A. pleuropneumoniae vaccine with SLW05 can protect against lethal H. parasuis infection, which provides a novel approach for developing an attenuated H. parasuis vaccine.

  3. Detection of Parasites and Parasitic Infections of Free-Ranging Wildlife on a Game Ranch in Zambia: A Challenge for Disease Control

    Directory of Open Access Journals (Sweden)

    Hetron Mweemba Munang'andu

    2012-01-01

    Full Text Available Ex-situ conservancies are expanding alternatives to livestock production in Zambia albeit the lack of information on circulating infectious parasites from wildlife. Therefore, 12 wildlife species were examined on a game ranch were all species were found to be infected by Rhipecephalus spp. Haemoparasite infections were estimated at 7.37% (n=95 with Babesia spp. detected in bushbuck (Tragelaphus scriptus; Anaplasma marginale in impala (Aepyceros melampus and puku (Kobus vardonii for the first time in Zambia. The majority of worm species isolated from bovids were not detected in equids and, vice versa. Our findings intimate ecological and behavioural patterns of some animals as deterministic to exposure. Kafue lechwe (Kobus leche kafuensis had the widest range of worm species with more infected organs than other animals suggesting their semi aquatic nature contributory to prolonged worm exposure compared to other animals. On the other hand, Kafue lechwe had the least tick infections attributable more to shorter attachment periods as they spend prolonged periods submerged in water. Our findings indicate the vital role that wildlife plays in the epidemiology of parasitic diseases. To reduce the infection burden, control measures should be focused on reducing transmission to highly susceptible animal species as described herein.

  4. Challenges in the chemotherapy of Chagas disease: Looking for possibilities related to the differences and similarities between the parasite and host

    Science.gov (United States)

    Sueth-Santiago, Vitor; Decote-Ricardo, Debora; Morrot, Alexandre; Freire-de-Lima, Celio Geraldo; Lima, Marco Edilson Freire

    2017-01-01

    Almost 110 years after the first studies by Dr. Carlos Chagas describing an infectious disease that was named for him, Chagas disease remains a neglected illness and a death sentence for infected people in poor countries. This short review highlights the enormous need for new studies aimed at the development of novel and more specific drugs to treat chagasic patients. The primary tool for facing this challenge is deep knowledge about the similarities and differences between the parasite and its human host. PMID:28289519

  5. Parasitic Diseases

    Science.gov (United States)

    ... water, a bug bite, or sexual contact. Some parasitic diseases are easily treated and some are not. Parasites ... can be seen with the naked eye. Some parasitic diseases occur in the United States. Contaminated water supplies ...

  6. 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

  7. Protection against lethal enterovirus 71 challenge in mice by a recombinant vaccine candidate containing a broadly cross-neutralizing epitope within the VP2 EF loop.

    Science.gov (United States)

    Xu, Longfa; He, Delei; Li, Zhiqun; Zheng, Jun; Yang, Lisheng; Yu, Miao; Yu, Hai; Chen, Yixin; Que, Yuqiong; Shih, James Wai Kuo; Liu, Gang; Zhang, Jun; Zhao, Qinjian; Cheng, Tong; Xia, Ningshao

    2014-01-01

    Human enterovirus 71 (EV71) is the main causative agent of hand, foot, and mouth disease (HFMD) and is associated with several severe neurological complications in the Asia-Pacific region. Here, we evaluated that while passive transfer of neutralizing monoclonal antibody (nMAb) against the VP2 protein protect against lethal EV71 infection in BALB/c mice. Protective nMAb were mapped to residues 141-155 of VP2 by peptide ELISA. High-resolution structural analysis showed that the epitope is part of the VP2 EF loop, which is the "puff" region that forms the "southern rim" of the canyon. Moreover, a three-dimensional structural characterization for the puff region with prior neutralizing epitopes and receptor-binding sites that can serve to inform vaccine strategies. Interestingly, using hepatitis B virus core protein (HBc) as a carrier, we demonstrated that the cross-neutralizing EV71 antibodies were induced, and the VP2 epitope immunized mice serum also conferred 100% in vivo passive protection. The mechanism of in vivo protection conferred by VP2 nMAb is in part attributed to the in vitro neutralizing titer and ability to bind authentic viral particles. Importantly, the anti-VP2(aa141-155) antibodies could inhibit the binding of human serum to EV71 virions showed that the VP2 epitope is immunodominant. Collectively, our results suggest that a broad-spectrum vaccine strategy targeting the high-affinity epitope of VP2 EF loop may elicits effective immune responses against EV71 infection.

  8. Protection of Hamsters by Venezuelan Equine Encephalitis Virus Candidate Vaccine V3526 Against Lethal Challenge by Mosquito Bite and Intraperitoneal Injection

    Science.gov (United States)

    2008-01-01

    the furin cleavage site in PE2 as well as a suppressor mutation in E1, was shown to protect mice, hamsters, and nonhuman primates challenged either by...previously to protect mice, hamsters, and nonhuman primates , there was concern that virus intro- duced by an infected mosquito might be more pathogenic than...and Rift Valley fever virus. Am J Trop Med Hyg 32: 1154–1163. 12. Karabatsos N, ed., 1985. International Catalogue of Arboviruses including Certain

  9. Lethal Midline Granuloma

    Directory of Open Access Journals (Sweden)

    Ghosh S.N

    1995-01-01

    Full Text Available Midline granuloma is a term with several synonyms: Stewart’s granuloma, granuloma gangraenescens nasi, lethal granuloma, polymorphous reticulosis 2-4 The conditiin is characterized by localized inflammation, destruction and often mutilation of tissues of the upper respiratory tract and face and, unless treated, it ends fatally within 12 to 18 months of onset. The pathological changes are those of nonspecific chronic inflammation to necrotizing vasculitis and granulomatosis. A case of lethal midline granuloma is reported.

  10. Protozoan Parasites.

    Science.gov (United States)

    Custodio, Haidee

    2016-02-01

    • Stool antigen detection for Cryptosporidium sp, Giardia lamblia and Entamoeba histolytica are now commercially available, have better sensitivity and specificity than the traditional stool microscopy, and are less dependent on personnel skill. Tests employing newer techniques with faster turnaround time are also available for diagnosing trichomoniasis.• Nitazoxanide, the only U.S. Food and Drug Administration-approved medication for therapy of cryptosporidiosis, is effective among immunocompetent patients. However, on the basis of strong evidence from multiple clinical trials, nitazoxanide is considered ineffective among immunocompromised patients. (14) • Giardiasis can be asymptomatic or have a chronic course leading to malabsorption and failure to thrive. It can be treated with metronidazole, tinidazole, or nitazoxanide. On the basis of growing observational studies, postinfectious and extraintestinal manifestations of giardiasis occur, but the mechanisms are unclear. Given the high prevalence of giardiasis, public health implications need to be defined. (16) • Eradicating E histolytica from the gastrointestinal tract requires only intraluminal agent therapy. Therapy for invasive illnesses requires use of imidazole followed by intraluminal agents to eliminate persistent intraluminal parasites. • Malaria is considered the most lethal parasitic infection, with Plasmodium falciparum as the predominant cause of mortality. P vivax and P ovale can be dormant in the liver, and primaquine is necessary to resolve infection by P vivax and P ovale. • Among immunocompetent patients, infection with Toxoplasma gondii may be asymptomatic, involve localized lymphadenopathy, or cause ocular infection. In immunocompromised patients, reactivation or severe infection is not uncommon. On the basis of limited observational studies (there are no well-controlled randomized trials), therapy is recommended for acute infection during pregnancy to prevent transmission to the

  11. H5N1 VLP vaccine induced protection in ferrets against lethal challenge with highly pathogenic H5N1 influenza viruses.

    Science.gov (United States)

    Mahmood, Kutubuddin; Bright, Rick A; Mytle, Nutan; Carter, Donald M; Crevar, Corey J; Achenbach, Jenna E; Heaton, Penny M; Tumpey, Terrence M; Ross, Ted M

    2008-10-03

    In this study, recombinant virus-like particles (VLPs) were evaluated as a candidate vaccine against emerging influenza viruses with pandemic potential. The VLPs are composed of the hemagglutinin (HA), neuraminidase (NA), and matrix 1 (M1) proteins of the H5N1 A/Indonesia/05/2005 (clade 2.1; [Indo/05]) virus, which were expressed using baculovirus in Spodoptera frugiperda (Sf9) cells. Ferrets received either 2 injections of the VLP vaccine at escalating doses (based on HA content), recombinant HA, or were mock vaccinated. Vaccinated ferrets were then challenged with either H5N1 Indo/05 or H5N1 A/Viet Nam 1203/2004 (VN/04) wild-type viruses. All ferrets that received the VLP vaccine survived regardless of the VLP dose or challenge strain, whereas seven of eight mock vaccinated ferrets died. The VLP vaccine induced HAI antibodies against the homologous H5N1 clade 2.1 strain, as well as heterologous strains from H5N1 clades 1, 2.2, and 2.3. The magnitude of the HAI titers correlated with VLP dose. Neutralizing antibody responses against the Indo/05 and VN/04 strains showed a similar pattern. Affinity of the anti-HA antibodies raised by the H5N1 Indo/05 VLPs had a higher association rate to the homologous clade 2.1 HA than to the clade 1 (VN/04) HA; however, once bound, antibodies had similar slow disassociation rates. These results provide support for continued development of the H5N1 VLPs as a candidate vaccine against pandemic influenza. Exploration of immunologic correlates of protection for H5N1 vaccines beyond HAI and neutralizing antibody responses is warranted.

  12. UV-inactivated vaccinia virus (VV) in a multi-envelope DNA-VV-protein (DVP) HIV-1 vaccine protects macaques from lethal challenge with heterologous SHIV

    Science.gov (United States)

    Jones, Bart G; Sealy, Robert E; Zhan, Xiaoyan; Freiden, Pamela J; Surman, Sherri L; Blanchard, James L.; Hurwitz, Julia L

    2012-01-01

    The pandemic of HIV-1 has continued for decades, yet there remains no licensed vaccine. Previous research has demonstrated the effectiveness of a multi-envelope, multi-vectored HIV-1 vaccine in a macaque-SHIV model, illustrating a potential means of combating HIV-1. Specifically, recombinant DNA, vaccinia virus (VV) and purified protein (DVP) delivery systems were used to vaccinate animals with dozens of antigenically-distinct HIV-1 envelopes for induction of immune breadth. The vaccinated animals controlled disease following challenge with a heterologous SHIV. This demonstration suggested that the antigenic cocktail vaccine strategy, which has succeeded in several other vaccine fields (e.g. pneumococcus), might also succeed against HIV-1. The strategy remains untested in an advanced clinical study, in part due to safety concerns associated with the use of replication-competent VV. To address this concern, we designed a macaque study in which psoralen/ultraviolet light-inactivated VV (UV VV) was substituted for replication-competent VV in the multi-envelope DVP protocol. Control animals received a vaccine encompassing no VV, or no vaccine. All VV vaccinated animals generated an immune response toward VV, and all vaccinated animals generated an immune response toward HIV-1 envelope. After challenge with heterologous SHIV 89.6P, animals that received replication-competent VV or UV VV experienced similar outcomes. They exhibited reduced peak viral loads, maintenance of CD4+ T cell counts and improved survival compared to control animals that received no VV or no vaccine; there were 0/15 deaths among all animals that received VV and 5/9 deaths among controls. Results define a practical means of improving VV safety, and encourage advancement of a promising multi-envelope DVP HIV-1 vaccine candidate. PMID:22425790

  13. Profound protection against respiratory challenge with a lethal H7N7 influenza A virus by increasing the magnitude of CD8(+) T-cell memory

    DEFF Research Database (Denmark)

    Christensen, Jan Pravsgaard; Doherty, P C; Branum, K C

    2000-01-01

    greatly increased subsequent to the H7N7 challenge, and though lung titers remained as high as those in naive controls for 5 days or more, the virus was cleared more rapidly. Expanding the CD8(+) memory T-cell pool (10%) by sequential priming with two different influenza A viruses (H3N2-->H1N1......The recall of CD8(+) T-cell memory established by infecting H-2(b) mice with an H1N1 influenza A virus provided a measure of protection against an extremely virulent H7N7 virus. The numbers of CD8(+) effector and memory T cells specific for the shared, immunodominant D(b)NP(366) epitope were...... for T-cell extravasation. The selective induction of CD8(+) T-cell memory can thus greatly limit the damage caused by a virulent influenza A virus, with the extent of protection being directly related to the number of available responders. Furthermore, a large pool of CD8(+) memory T cells may be only...

  14. Metatropic dysplasia lethal variants

    Energy Technology Data Exchange (ETDEWEB)

    Hall, Christine M. [Department of Radiology, Great Ormond Street Hospital for Children NHS Trust, WCIN 3JH, London (United Kingdom); Elcioglu, Nursel H. [Department of Pediatric Genetics, Marmara University Hospital, Istanbul (Turkey)

    2004-01-01

    Background: The metatropic dysplasia group includes fibrochondrogenesis, Schneckenbecken dysplasia and metatropic dysplasia (various forms). The overlapping features of this group with other dysplasias may cause diagnostic confusion, particularly in perinatal lethal cases. Objective: To attempt to classify the radiological findings of the presented eight sporadic cases based on a broad review of the perinatally lethal metatropic group of conditions and to discuss some overlapping features in the light of current knowledge. Results: The first four cases are of recognised conditions, namely lethal metatropic dysplasia (Type 2) or hyperchondrogenesis, lethal hyperplastic metatropic dysplasia (Type 1) and fibrochondrogenesis. The remaining four cases cannot be categorised accurately and are different from each other but with some features of the metatropic group of dysplasias. Conclusions: The dysplasias within the metatropic dysplasia group are phenotypically distinct from many forms of chondrodysplasia but the pathogenesis still remains poorly understood from the morphological and molecular perspectives. Chondro-osseous morphology might be helpful in all lethal cases especially in our last four cases. (orig.)

  15. Effects of cobalt 60 ionizing radiation on the metabolism and infectivity of a parasitic protozoa, Toxoplasma gondii

    Energy Technology Data Exchange (ETDEWEB)

    Hiramoto, Roberto M.; Galisteo Junior, Andres J.; Andrade Junior, Heitor F. [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina. Instituto de Medicina Tropical de Sao Paulo

    1999-11-01

    Toxoplasma gondii infection causes severe and lethal disease on fetus, AIDS patients and recipients of organ transplants. There are few reports of the use of ionizing radiation to attenuate or abolish parasite growth, without and detailed study on induced alterations or effective doses. We reported that the lower dose of {sup 60} Co radiation that abolishes parasite growth was 200 Gy, and in this report, we described the viability, cell invasion, metabolism and immunogenicity of this parasite after irradiation. We analyze the viability (vital staining), metabolism, by MTT oxidative conversion, protein metabolism, by {sup 3} H-proline and nucleic acid synthesis, by {sup 3} H-hypoxanthine incorporation in short terms cultures. Parasite invasion was tested in LLC-MK2 cell in culture. The irradiated parasites show the same viability and invasiveness of viable parasites, without any interference of the radiation in the oxidative, proteic or nucleic acid metabolism. When mice injected with 10{sup 7} irradiated parasites by intraperitoneal route, were challenged 6 weeks later with viable parasites, they showed partial resistance to infection, with higher survival time. Antibody specificity was tested in sera from those animals, before challenging, and presented the same epitopic specificity of infected and treated animals, but diverse from mice injected with formaldehyde killed parasite, by Western-blot analysis against SDS-PAGE isolated T. gondii antigens. Those data suggests that irradiated parasites maintain its invasiveness, inducing a partial immunity and similar humoral immunogenicity than viable parasites, but without any evidence of reproductive capacity. (author) 18 refs., 7 figs.

  16. Parasites: Water

    Science.gov (United States)

    ... Tropical Diseases Laboratory Diagnostic Assistance [DPDx] 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 ...

  17. Synthetic lethal approaches for assessing combinatorial efficacy of chemotherapeutic drugs.

    Science.gov (United States)

    Jackson, Rebecca A; Chen, Ee Sin

    2016-06-01

    The recent advances in pharmacogenomics have made personalized medicine no longer a pipedream but a precise and powerful way to tailor individualized cancer treatment strategies. Cancer is a devastating disease, and contemporary chemotherapeutic strategies now integrate several agents in the treatment of some types of cancer, with the intent to block more than one target simultaneously. This constitutes the premise of synthetic lethality, an attractive therapeutic strategy already demonstrating clinical success in patients with breast and ovarian cancers. Synthetic lethal combinations offer the potential to also target the hitherto "undruggable" mutations that have challenged the cancer field for decades. However, synthetic lethality in clinical cancer therapy is very much still in its infancy, and selecting the most appropriate combinations-or synthetic lethal pairs-is not always an intuitive process. Here, we review some of the recent progress in identifying synthetic lethal combinations and their potential for therapy and highlight some of the tools through which synthetic lethal pairs are identified.

  18. Development of non-lethal methods for investigation of actinide uptake by wildlife

    Energy Technology Data Exchange (ETDEWEB)

    Johansen, M.; Child, D.; Davis, E.; Harrison, J.; Hotchkis, M.; Payne, T.; Thiruvoth, S. [Australian Nuclear Science and Technology Org. (Australia); Wood, M. [University of Salford (United Kingdom)

    2014-07-01

    There is growing interest in the use of non-lethal methods in radioecology and an International Union of Radioecology Task Group has been established to facilitate international cooperation in this field (http://iur-uir.org/en/task-groups/id-19-non-lethal-methods-in-radioecology). In this paper, we evaluate the use of lethally-, and non-lethally obtained samples (various body tissues, excreta and blood withdrawals as well as parasites and found bones) as indicators of contamination. Samples of mammals and reptiles were collected from the semi-arid former weapons test site at Maralinga, Australia and analysed for thorium, plutonium, and uranium isotopes by accelerator mass spectrometry and alpha-spectrometry. Most samples were of low mass and presented analytical challenges as a result. The plutonium concentrations in blood withdrawn from the marginal ear veins of Oryctolagus cuniculus (European rabbit) were successfully analysed using small samples (0.2 -7.9 ml, below the ∼10 ml threshold for safe extraction of blood from these rabbits). The results demonstrate that small-volume blood samples can serve as indicators of the presence of plutonium absorbed within other tissues (e.g., muscle, bone). However, the magnitude of the blood plutonium masses were poorly correlated with those in muscle and bone due to the presence of a small number of outliers (without the outliers, correlations improved to r = +0.66 and r = +0.51 for muscle and bone respectively). The activity concentrations in parasitic ticks were relatively high compared with those of their hosts Pseudomys hermannsburgensis (sandy inland mouse) and Ctenophorus cristatus (crested dragon lizard). Successful measurement of tick samples indicates a potential for use of parasites as general indicators of contamination within host organisms. The concentrations of actinides in found bones of Macropus rufus (red kangaroo) and O. cuniculus demonstrated potential for their use as indicators of the areal extent of

  19. Acquisition Challenges of a Lethal Virus

    Science.gov (United States)

    2014-10-01

    virus is insect -borne. 27 Defense AT&L: September–October 2014 Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting burden...product in Tekmira’s TKM-Ebola, a drug candidate based on a gene- silencing technique used by plants and animals called RNA interference ( RNAi ...In the past decade, RNAi has become one of the most im- portant innovations in the field of drug discovery and de- velopment. In fact, in 2006 the

  20. Brucella abortus Omp19 recombinant protein subcutaneously co-delivered with an antigen enhances antigen-specific T helper 1 memory responses and induces protection against parasite challenge.

    Science.gov (United States)

    Coria, Lorena M; Ibañez, Andrés E; Pasquevich, Karina A; Cobiello, Paula L González; Frank, Fernanda M; Giambartolomei, Guillermo H; Cassataro, Juliana

    2016-01-20

    The discovery of effective adjuvants for many vaccines especially those with limited commercial appeal, such as vaccines to poverty-related diseases, is required. In this work, we demonstrated that subcutaneous co-administration of mice with the outer membrane protein U-Omp19 from Brucella spp. plus OVA as antigen (Ag) increases Ag-specific T cell proliferation and T helper (Th) 1 immune responses in vitro and in vivo. U-Omp19 treated dendritic cells promote IFN-γ production by specific CD4(+) T cells and increases T cell proliferation. U-Omp19 co-administration induces the production of Ag specific effector memory T cell populations (CD4(+) CD44(high) CD62L(low) T cells). Finally, subcutaneous co-administration of U-Omp19 with Trypanosoma cruzi Ags confers protection against virulent parasite challenge, reducing parasitemia and weight loss while increasing mice survival. These results indicate that the bacterial protein U-Omp19 when delivered subcutaneously could be a suitable component of vaccine formulations against infectious diseases requiring Th1 immune responses.

  1. Parasitic Colitis

    Science.gov (United States)

    Hechenbleikner, Elizabeth M.; McQuade, Jennifer A.

    2015-01-01

    Over one billion people worldwide harbor intestinal parasites. Parasitic intestinal infections have a predilection for developing countries due to overcrowding and poor sanitation but are also found in developed nations, such as the United States, particularly in immigrants or in the setting of sporadic outbreaks. Although the majority of people are asymptomatically colonized with parasites, the clinical presentation can range from mild abdominal discomfort or diarrhea to serious complications, such as perforation or bleeding. Protozoa and helminths (worms) are the two major classes of intestinal parasites. Protozoal intestinal infections include cryptosporidiosis, cystoisosporiasis, cyclosporiasis, balantidiasis, giardiasis, amebiasis, and Chagas disease, while helminth infections include ascariasis, trichuriasis, strongyloidiasis, enterobiasis, and schistosomiasis. Intestinal parasites are predominantly small intestine pathogens but the large intestine is also frequently involved. This article highlights important aspects of parasitic infections of the colon including epidemiology, transmission, symptoms, and diagnostic methods as well as appropriate medical and surgical treatment. PMID:26034403

  2. Parasitic Colitis

    OpenAIRE

    Hechenbleikner, Elizabeth M.; McQuade, Jennifer A.

    2015-01-01

    Over one billion people worldwide harbor intestinal parasites. Parasitic intestinal infections have a predilection for developing countries due to overcrowding and poor sanitation but are also found in developed nations, such as the United States, particularly in immigrants or in the setting of sporadic outbreaks. Although the majority of people are asymptomatically colonized with parasites, the clinical presentation can range from mild abdominal discomfort or diarrhea to serious complication...

  3. Cat parasites

    OpenAIRE

    Vošická, Kristýna

    2016-01-01

    The content of this bachelor thesis describes a different variety of cat parasites. This study discovers that the most infected group of the outdoor cats due to the fact that these animals are not provided with the same care as the household pets. Those cats are usually not vaccinated, not rid of worms, no one takes care of their fur and so they tend to become a host for the parasites. There are several kinds of parasites which attack cats. Among those belong the skin parasites like a cat fle...

  4. Effects of lethal and non-lethal malaria on the mononuclear phagocyte system

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Tosta

    1983-03-01

    Full Text Available The effects ofone non-lethal species ofmalarialparasite, Plasmodium yoelii, and one lethal species, P. berghei, on the mononuclear phagocyte system (MPS of BALB/c mice were studied. P. yoelii caused a greater and more sustained expansion and activation of the MPS, and the two major populations of spleen phagocytic cells-red pulp and marginal zone macrophages - exhibited a greater increase in numbers in this infection. During the course of P. berghei mataria, the spleen was progressively occupied by haematopoietic tissue and, at the terminal stage of infection, an extensive depletion of lymphocytes and macrophages was apparent. The possibility was suggested that the outcome of mataria may be inftuenced by the particular way the parasite interacts with the MPS.

  5. Parasite stress promotes homicide and child maltreatment.

    Science.gov (United States)

    Thornhill, Randy; Fincher, Corey L

    2011-12-12

    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.

  6. 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...

  7. Crash Lethality Model

    Science.gov (United States)

    2014-02-05

    26,800 400 Ethyl Benzene 0.121 40,900 4,900 Ethyl Ether 0.094 33,800 3,200 Gasoline 0.055 43,700 2,400 Hexane 0.074 44,700 3,300 Heptane 0.101...the product of projectile diameter and target weight. The animal lethality data were entered into MATLAB© and the function cftool() was used to...generate a logistic function. The x-axis represents a ratio of kinetic energy to the product of projectile diameter and target weight as defined by

  8. New polymorphic microsatellite markers derived from hemocyte cDNA library of Manila clam Ruditapes philippinarum challenged by the protozoan parasite Perkinsus olseni

    Science.gov (United States)

    Kang, Hyun-Sil; Hong, Hyun-Ki; Park, Kyung-Il; Cho, Moonjae; Youn, Seok-Hyun; Choi, Kwang-Sik

    2017-02-01

    Manila clam Ruditapes philippinarum is one of the most important benthic animals in the coastal north Pacific region, where clam populations have been mixed genetically through trade and aquaculture activities. Accordingly, identification of the genetically different clam populations has become one of the most important issues to manage interbreeding of the local and introduced clam populations. To identify genetically different populations of clam populations, we developed 11 expressed sequence tag (EST)-microsatellite loci (i.e., simple sequence repeat, SSR) from 1,128 clam hemocyte cDNA clones challenged by the protozoan parasite Perkinsus olseni. Genotype analysis using the markers developed in this study demonstrated that clams from a tidal flat on the west coast contained 6 to 19 alleles per locus, and a population from Jeju Island had 4 to 20 alleles per locus. The expected heterozygosity of the 2 clam populations ranged from 0.472 to 0.919 for clams from the west coast, and 0.494 to 0.919 for clams from Jeju Island, respectively. Among the 11 loci discovered in this study, 7 loci significantly deviated from the Hardy-Weinberg equilibrium after Bonferroni correction. The 5 loci developed in this study also successfully amplified the SSRs of R. variegatus, a clam species taxonomically very close to R. philippinarum, from Hong Kong and Jeju Island. We believe that the 11 novel polymorphic SSR developed in this study can be utilized successfully in Manila clam genetic diversity analysis, as well as in genetic discrimination of different clam populations.

  9. New polymorphic microsatellite markers derived from hemocyte cDNA library of Manila clam Ruditapes philippinarum challenged by the protozoan parasite Perkinsus olseni

    Science.gov (United States)

    Kang, Hyun-Sil; Hong, Hyun-Ki; Park, Kyung-Il; Cho, Moonjae; Youn, Seok-Hyun; Choi, Kwang-Sik

    2017-03-01

    Manila clam Ruditapes philippinarum is one of the most important benthic animals in the coastal north Pacific region, where clam populations have been mixed genetically through trade and aquaculture activities. Accordingly, identification of the genetically different clam populations has become one of the most important issues to manage interbreeding of the local and introduced clam populations. To identify genetically different populations of clam populations, we developed 11 expressed sequence tag (EST)-microsatellite loci (i.e., simple sequence repeat, SSR) from 1,128 clam hemocyte cDNA clones challenged by the protozoan parasite Perkinsus olseni. Genotype analysis using the markers developed in this study demonstrated that clams from a tidal flat on the west coast contained 6 to 19 alleles per locus, and a population from Jeju Island had 4 to 20 alleles per locus. The expected heterozygosity of the 2 clam populations ranged from 0.472 to 0.919 for clams from the west coast, and 0.494 to 0.919 for clams from Jeju Island, respectively. Among the 11 loci discovered in this study, 7 loci significantly deviated from the Hardy-Weinberg equilibrium after Bonferroni correction. The 5 loci developed in this study also successfully amplified the SSRs of R. variegatus, a clam species taxonomically very close to R. philippinarum, from Hong Kong and Jeju Island. We believe that the 11 novel polymorphic SSR developed in this study can be utilized successfully in Manila clam genetic diversity analysis, as well as in genetic discrimination of different clam populations.

  10. Evaluation of lethal and non-lethal sampling methods for the detection of white sturgeon iridovirus infection in white sturgeon, Acipenser transmontanus (Richardson).

    Science.gov (United States)

    Drennan, J D; Lapatra, S E; Samson, C A; Ireland, S; Eversman, K F; Cain, K D

    2007-06-01

    Pectoral fin tissue of white sturgeon was investigated as a potential non-lethal sample source for the detection of white sturgeon iridovirus (WSIV) infection. Histopathology and polymerase chain reaction (PCR) results using fin tissue were compared with the standard lethal histopathology sampling method that utilizes head tissue. Tissues for each of the three sampling methods were collected weekly for 8 weeks from individual sturgeon undergoing an experimental cohabitation challenge with fish infected with the Abernathy isolate of WSIV. Non-lethal fin histopathological evaluation did not reveal infection during the first 3 weeks of sampling, while non-lethal PCR and the lethal method were variable. However, all three sampling methods were equally capable of identifying infection from 4 to 8 weeks post-exposure. Of the survivors tested, all were negative by PCR and the lethal method, and only one fish was identified as being positive by non-lethal fin histopathology. In another experiment, all three sampling methods were applied to asymptomatic WSIV carriers in a case study conducted at the Kootenai Tribal Sturgeon Conservation Hatchery. Results showed that both lethal and non-lethal fin histopathology were equally effective in detecting infection, but PCR was unable to identify this strain of WSIV. Depending on the virus isolate, these results suggest that non-lethal sampling of fin tissue (histopathology or PCR) is comparable with the lethal sampling method at identifying WSIV infection once infection is established, and under certain circumstances may provide an alternative to lethal sampling.

  11. Derivation of Human Lethal Doses

    Science.gov (United States)

    2006-01-19

    Hardman, JG; Limbird, LE; Goodman Gilman , A, (editors). (2001) Goodman and Gilman’s The Pharmacological Basis of Therapeutics. New York, NY: McGraw... Goodman and Gilman’s N/A No LDLo, MLD, or lethal dose for humans; no LD50 for rat or mouse NIOSH N/A No LDLo, MLD, or lethal dose for humans; no LD50...Basis of Therapeutics– Goodman and Gilman’s N/A No LDLo, MLD, or lethal dose for humans; no LD50 for rat or mouse NIOSH N/A No LDLo, MLD, or lethal

  12. Key tissue targets responsible for anthrax toxin-induced-lethality

    Science.gov (United States)

    Liu, Shihui; Zhang, Yi; Moayeri, Mahtab; Liu, Jie; Crown, Devorah; Fattah, Rasem; Wein, Alexander N.; Yu, Zu-Xi; Finkel, Toren; Leppla, Stephen H.

    2014-01-01

    Summary Bacillus anthracis, the causative agent of anthrax disease, is lethal due to the actions of two exotoxins, anthrax lethal toxin (LT) and edema toxin (ET). The key tissue targets responsible for the lethal effects of these toxins are unknown. Here we generated cell-type specific anthrax toxin receptor capillary morphogenesis protein-2 (CMG2)-null mice and cell-type specific CMG2-expressing mice and challenged them with the toxins. Our results show that lethality induced by LT and ET occur through damage to distinct cell-types; while targeting cardiomyocytes and vascular smooth muscle cells is required for LT-induced mortality, ET-induced lethality occurs mainly through its action in hepatocytes. Surprisingly, and in contradiction to what has been previously postulated, targeting of endothelial cells by either toxin does not appear to contribute significantly to lethality. Our findings demonstrate that B. anthracis has evolved to use LT and ET to induce host lethality by coordinately damaging two distinct vital systems. PMID:23995686

  13. A large proportion of asymptomatic Plasmodium infections with low and sub-microscopic parasite densities in the low transmission setting of Temotu Province, Solomon Islands: challenges for malaria diagnostics in an elimination setting

    Directory of Open Access Journals (Sweden)

    Harris Ivor

    2010-09-01

    PCR positive P. falciparum, but failed to detect 12/13 microscopy and PCR positive P. vivax infections. Conclusion Asymptomatic malaria infections and infections with low and sub-microscopic parasite densities are highly prevalent in Temotu province where malaria transmission is low. This presents a challenge for elimination since the large proportion of the parasite reservoir will not be detected by standard active and passive case detection. Therefore effective mass screening and treatment campaigns will most likely need more sensitive assays such as a field deployable molecular based assay.

  14. Diagnosis of Parasitic Diseases

    Science.gov (United States)

    ... Laboratory Diagnostic Assistance [DPDx] Parasites Home Diagnosis of Parasitic Diseases Recommend on Facebook Tweet Share Compartir On this ... the United States cannot diagnose parasites? How are parasitic diseases diagnosed? Many kinds of lab tests are available ...

  15. Disease dynamics in a specialized parasite of ant societies

    DEFF Research Database (Denmark)

    Andersen, Sandra Breum; Ferrari, Matthew; Evans, Harry C.

    2012-01-01

    Coevolution between ant colonies and their rare specialized parasites are intriguing, because lethal infections of workers may correspond to tolerable chronic diseases of colonies, but the parasite adaptations that allow stable coexistence with ants are virtually unknown. We explore the trade......-offs experienced by Ophiocordyceps parasites manipulating ants into dying in nearby graveyards. We used field data from Brazil and Thailand to parameterize and fit a model for the growth rate of graveyards. We show that parasite pressure is much lower than the abundance of ant cadavers suggests...

  16. Lethal and Sublethal Effects of Insecticides on the Egg Parasitoid Telenomus podisi (Hymenoptera: Platygastridae).

    Science.gov (United States)

    Turchen, L M; Golin, V; Butnariu, A R; Guedes, R N C; Pereira, M J B

    2016-02-01

    Insecticide use remains controversial, and subjected to increasing environmental and health concerns, even when recent insecticide groups are considered. Neonicotinoids and even bioinsecticides are in the forefront of discussions regarding their nontarget safety. The ubiquitous focus on the lethal effects of insecticides on nontarget species has been expanding to sublethal effects, as sublethal exposure extends for a longer time and affects a broader range of (nontarget) species. Here we explored the lethal and sublethal effects of a lambda-cyhalothrin + thiamethoxan mixture, the neonicotinoid imidacloprid, and the bioinsecticide azadirachtin on the egg parasitoid Telenomus podisi Ashmead, an important parasitoid of stink bug Euschistus heros (F.), a key soybean pest in neotropical America. Contact with dry insecticide residue on glass surface and (parasitized and healthy) host egg immersion exposure bioassays were performed, assessing their acute lethal effects, and their potential sublethal impairment of parasitism, adult emergence, and fertility of the egg parasitoid. Both imidacloprid and the insecticide mixture exhibited high acute lethal activity toward the parasitoid under contact with dry insecticide residue. These insecticides compromised parasitism and wasp emergence when exposure took place before parasitism. In contrast, azadirachtin did not affect adult survival. However, this bioinsecticide compromised parasitism and progeny production, impairing the female parasitoid reproductive potential. Our results indicate strong negative effects of imidacloprid, and specially of the mixture lambda-cyhalthrin + thiamethoxan. However, even azadirachtin, which exhibited low acute lethality, exhibited significant negative sublethal effects on parasitism and population growth of egg parasitoid, cautioning against their use and the need of semifield and field assessments to confirm such an impact. © The Authors 2015. Published by Oxford University Press on behalf of

  17. Synergistic parasite-pathogen interactions mediated by host immunity can drive the collapse of honeybee colonies.

    Directory of Open Access Journals (Sweden)

    Francesco Nazzi

    Full Text Available The health of the honeybee and, indirectly, global crop production are threatened by several biotic and abiotic factors, which play a poorly defined role in the induction of widespread colony losses. Recent descriptive studies suggest that colony losses are often related to the interaction between pathogens and other stress factors, including parasites. Through an integrated analysis of the population and molecular changes associated with the collapse of honeybee colonies infested by the parasitic mite Varroa destructor, we show that this parasite can de-stabilise the within-host dynamics of Deformed wing virus (DWV, transforming a cryptic and vertically transmitted virus into a rapidly replicating killer, which attains lethal levels late in the season. The de-stabilisation of DWV infection is associated with an immunosuppression syndrome, characterized by a strong down-regulation of the transcription factor NF-κB. The centrality of NF-κB in host responses to a range of environmental challenges suggests that this transcription factor can act as a common currency underlying colony collapse that may be triggered by different causes. Our results offer an integrated account for the multifactorial origin of honeybee losses and a new framework for assessing, and possibly mitigating, the impact of environmental challenges on honeybee health.

  18. Synergistic parasite-pathogen interactions mediated by host immunity can drive the collapse of honeybee colonies.

    Science.gov (United States)

    Nazzi, Francesco; Brown, Sam P; Annoscia, Desiderato; Del Piccolo, Fabio; Di Prisco, Gennaro; Varricchio, Paola; Della Vedova, Giorgio; Cattonaro, Federica; Caprio, Emilio; Pennacchio, Francesco

    2012-01-01

    The health of the honeybee and, indirectly, global crop production are threatened by several biotic and abiotic factors, which play a poorly defined role in the induction of widespread colony losses. Recent descriptive studies suggest that colony losses are often related to the interaction between pathogens and other stress factors, including parasites. Through an integrated analysis of the population and molecular changes associated with the collapse of honeybee colonies infested by the parasitic mite Varroa destructor, we show that this parasite can de-stabilise the within-host dynamics of Deformed wing virus (DWV), transforming a cryptic and vertically transmitted virus into a rapidly replicating killer, which attains lethal levels late in the season. The de-stabilisation of DWV infection is associated with an immunosuppression syndrome, characterized by a strong down-regulation of the transcription factor NF-κB. The centrality of NF-κB in host responses to a range of environmental challenges suggests that this transcription factor can act as a common currency underlying colony collapse that may be triggered by different causes. Our results offer an integrated account for the multifactorial origin of honeybee losses and a new framework for assessing, and possibly mitigating, the impact of environmental challenges on honeybee health.

  19. Evaluation of Lethal Giant Larvae as a Schistosomiasis Vaccine Candidate

    Science.gov (United States)

    Cao, Yufan; Qiao, Hongbin; Shi, Yanli; Han, Yu; Liu, Jinming; Li, Hao; Lu, Ke; Lin, Jiaojiao

    2016-01-01

    Schistosomiasis is a neglected tropical disease of humans, and it is considered to be the second most devastating parasitic disease after malaria. Eggs produced by normally developed female worms are important in the transmission of the parasite, and they responsible for the pathogenesis of schistosomiasis. The tumor suppressor gene lethal giant larvae (lgl) has an essential function in establishing apical-basal cell polarity, cell proliferation, differentiation, and tissue organization. In our earlier study, downregulation of the lgl gene induced a significant reduction in the egg hatching rate of Schistosoma japonicum (Sj) eggs. In this study, the Sjlgl gene was used as a vaccine candidate against schistosomiasis, and vaccination achieved and maintained a stable reduction of the egg hatching rate, which is consistent with previous studies, in addition to reducing the worm burden and liver egg burden in some trials. PMID:27957496

  20. Evaluation of Lethal Giant Larvae as a Schistosomiasis Vaccine Candidate

    Directory of Open Access Journals (Sweden)

    Yufan Cao

    2016-01-01

    Full Text Available Schistosomiasis is a neglected tropical disease of humans, and it is considered to be the second most devastating parasitic disease after malaria. Eggs produced by normally developed female worms are important in the transmission of the parasite, and they responsible for the pathogenesis of schistosomiasis. The tumor suppressor gene lethal giant larvae (lgl has an essential function in establishing apical-basal cell polarity, cell proliferation, differentiation, and tissue organization. In our earlier study, downregulation of the lgl gene induced a significant reduction in the egg hatching rate of Schistosoma japonicum (Sj eggs. In this study, the Sjlgl gene was used as a vaccine candidate against schistosomiasis, and vaccination achieved and maintained a stable reduction of the egg hatching rate, which is consistent with previous studies, in addition to reducing the worm burden and liver egg burden in some trials.

  1. [The "lethal white foal" syndrome].

    Science.gov (United States)

    Blendinger, C; Müller, G; Bostedt, H

    1994-06-01

    The lethal white foal syndrome (congenital intestinal aganglionosis) was diagnosed by history, clinical signs and pathological findings in a female foal, born in March 1992, that was an offspring of two overo-spotted paint horses. The syndrome is a congenital innervation defect of the gastrointestinal tract. A literature review of this condition, relatively unknown in Germany, is given.

  2. Parasitic zoonoses in India: an overview.

    Science.gov (United States)

    Singh, B B; Sharma, R; Sharma, J K; Juyal, P D

    2010-12-01

    Parasitic zoonotic diseases are prevalent throughout India at varying rates. First reports of zoonotic parasites and new emerging diseases have been recorded in both the human and animal populations in recent decades. The prevalence of zoonotic parasites is likely to be an underestimate, owing to the lack of proper surveillance and the shortage of information about the existence of asymptomatic animal carriers. Emergence of diseases such as human echinococcosis/hydatidosis, neurocysticercosis, cryptosporidiosis and toxoplasmosis in those with acquired immune deficiency syndrome, together with the re-emergence of cutaneous leishmaniosis, poses a serious threat in India and the prevention and control of these parasitic zoonoses, and others, is a great challenge.

  3. Internal parasite management in grazing livestock.

    Science.gov (United States)

    Kumar, Niranjan; Rao, Thakur Krishan Shankar; Varghese, Anju; Rathor, Veer Singh

    2013-10-01

    It is a challenging task to control internal parasites in grazing livestock even by applying multi label and multi directional approach. It is impossible to draw general recommendations to control parasitic diseases due to varied geo-climatic conditions and methods adopted for rearing the livestock in the country like India. In view of increasing incidence of anti-parasitic drug resistance in animals, there is an urgent need to design sustainable parasite control strategy which must include on the host as well as off the host control measures to harvest the maximum productivity from the animal for an indefinite period.

  4. Parasitic Pneumonia and Lung Involvement

    Directory of Open Access Journals (Sweden)

    Attapon Cheepsattayakorn

    2014-01-01

    Full Text Available Parasitic infestations demonstrated a decline in the past decade as a result of better hygiene practices and improved socioeconomic conditions. Nevertheless, global immigration, increased numbers of the immunocompromised people, international traveling, global warming, and rapid urbanization of the cities have increased the susceptibility of the world population to parasitic diseases. A number of new human parasites, such as Plasmodium knowlesi, in addition to many potential parasites, have urged the interest of scientific community. A broad spectrum of protozoal parasites frequently affects the respiratory system, particularly the lungs. The diagnosis of parasitic diseases of airway is challenging due to their wide varieties of clinical and roentgenographic presentations. So detailed interrogations of travel history to endemic areas are critical for clinicians or pulmonologists to manage this entity. The migrating adult worms can cause mechanical airway obstruction, while the larvae can cause airway inflammation. This paper provides a comprehensive review of both protozoal and helminthic infestations that affect the airway system, particularly the lungs, including clinical and roentgenographic presentations, diagnostic tests, and therapeutic approaches.

  5. 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.

  6. Genetic Vaccination against Experimental Infection with Myotropic Parasite Strains of Trypanosoma cruzi

    Directory of Open Access Journals (Sweden)

    Adriano Fernando Araújo

    2014-01-01

    Full Text Available In earlier studies, we reported that a heterologous prime-boost regimen using recombinant plasmid DNA followed by replication-defective adenovirus vector, both containing Trypanosoma cruzi genes encoding trans-sialidase (TS and amastigote surface protein (ASP 2, provided protective immunity against experimental infection with a reticulotropic strain of this human protozoan parasite. Herein, we tested the outcome of genetic vaccination of F1 (CB10XBALB/c mice challenged with myotropic parasite strains (Brazil and Colombian. Initially, we determined that the coadministration during priming of a DNA plasmid containing the murine IL-12 gene improved the immune response and was essential for protective immunity elicited by the heterologous prime-boost regimen in susceptible male mice against acute lethal infections with these parasites. The prophylactic or therapeutic vaccination of resistant female mice led to a drastic reduction in the number of inflammatory infiltrates in cardiac and skeletal muscles during the chronic phase of infection with either strain. Analysis of the electrocardiographic parameters showed that prophylactic vaccination reduced the frequencies of sinus arrhythmia and atrioventricular block. Our results confirmed that prophylactic vaccination using the TS and ASP-2 genes benefits the host against acute and chronic pathologies caused by T. cruzi and should be further evaluated for the development of a veterinary or human vaccine against Chagas disease.

  7. 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.

  8. Non-lethal weapons and their characteristics

    OpenAIRE

    DAMJANOVIC DRAGAN Z.

    2015-01-01

    Non-lethal weapons, also called less-lethal weapons, less-than lethal weapons, non-deadly weapons, compliance weapons, or pain-inducing weapons are weapons intended to be less likely to kill a living target than conventional weapons. It is often understood that accidental, incidental, and correlative casualties are risked wherever force is applied, but non-lethal weapons try to minimise the risk as much as possible. Non-lethal weapons are used in combat situations to limit the escalation of c...

  9. NON-LETHAL WEAPONS AND THEIR CHARACTERISTICS

    OpenAIRE

    2015-01-01

    Non-lethal weapons, also called less-lethal weapons, less-than lethal weapons, non-deadly weapons, compliance weapons, or pain-inducing weapons are weapons intended to be less likely to kill a living target than conventional weapons. It is often understood that accidental, incidental, and correlative casualties are risked wherever force is applied, but non-lethal weapons try to minimise the risk as much as possible. Non-lethal weapons are used in combat situations to limit the escalation of c...

  10. Finding parasites and finding challenges: improved diagnostic access and trends in reported malaria and anti-malarial drug use in Livingstone district, Zambia

    Directory of Open Access Journals (Sweden)

    Masaninga Freddie

    2012-10-01

    Full Text Available Abstract Background Understanding the impact of malaria rapid diagnostic test (RDT use on management of acute febrile disease at a community level, and on the consumption of anti-malarial medicines, is critical to the planning and success of scale-up to universal parasite-based diagnosis by health systems in malaria-endemic countries. Methods A retrospective study of district-wide community-level RDT introduction was conducted in Livingstone District, Zambia, to assess the impact of this programmed on malaria reporting, incidence of mortality and on district anti-malarial consumption. Results Reported malaria declined from 12,186 cases in the quarter prior to RDT introduction in 2007 to an average of 12.25 confirmed and 294 unconfirmed malaria cases per quarter over the year to September 2009. Reported malaria-like fever also declined, with only 4,381 RDTs being consumed per quarter over the same year. Reported malaria mortality declined to zero in the year to September 2009, and all-cause mortality declined. Consumption of artemisinin-based combination therapy (ACT dropped dramatically, but remained above reported malaria, declining from 12,550 courses dispensed by the district office in the quarter prior to RDT implementation to an average of 822 per quarter over the last year. Quinine consumption in health centres also declined, with the district office ceasing to supply due to low usage, but requests for sulphadoxine-pyrimethamine (SP rose to well above previous levels, suggesting substitution of ACT with this drug in RDT-negative cases. Conclusions RDT introduction led to a large decline in reported malaria cases and in ACT consumption in Livingstone district. Reported malaria mortality declined to zero, indicating safety of the new diagnostic regime, although adherence and/or use of RDTs was still incomplete. However, a deficiency is apparent in management of non-malarial fever, with inappropriate use of a low-cost single dose drug, SP

  11. An overview of the future of non-lethal weapons.

    Science.gov (United States)

    Alexander, J B

    2001-01-01

    During the past decade, vast changes have occurred in the geopolitical landscape and the nature of the types of conflicts in which technologically developed countries have been involved. While the threat of conventional war remains, forces have been more frequently deployed in situations that require great restraint. Adversaries are often likely to be elusive and commingled with noncombatants. There has been some shift in public opinion away from tolerance of collateral casualties. Therefore there is a need to be able to apply force while limiting casualties. Non-lethal weapons provide part of the solution. Among the changes that will influence the future have been studies by the US and NATO concerning the use of non-lethal weapons, coincidental with increased funding for their development and testing. New concepts and policies have recently been formalized. Surprisingly, the most strident objections to the implementation of non-lethal weapons have come from organizations that are ostensibly designed to protect non-combatants. These arguments are specious and, while technically and academically challenging, actually serve to foster an environment that will result in the deaths of many more innocent civilians. They misconstrue technology with human intent. The reasons for use of force will not abate. Alternatives to bombs, missiles, tanks and artillery must therefore be found. Non-lethal weapons are not a panacea but do offer the best hope of minimizing casualties while allowing nations or alliances the means to use force in protection of national or regional interests.

  12. 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.

  13. Parasitic Diseases: Glossary

    Science.gov (United States)

    ... multicellular organism that is generally visible to the naked eye in its adult stages. Helminths can be ... with parasites such as Cyclospora and Cryptosporidium . (Also see " coccidian " and " sporulation .") Back To Top P Parasite: ...

  14. Women and Parasitic Diseases

    Science.gov (United States)

    ... Resources How to Find A Physician Diagnosis of Parasitic Diseases Statistics More Information Get Email Updates To receive ... often need special consideration when being treated for parasitic diseases in order to avoid harm to the fetus, ...

  15. Children and Parasitic Diseases

    Science.gov (United States)

    ... CDC.gov . Parasites About Parasites Animals Blood Food Insects Water Education and Training CDC Bottle Bioassay References ... flowing water. It can cause itching and impaired vision in children, and lead to blindness in adulthood. ...

  16. Immunity to parasitic infection

    National Research Council Canada - National Science Library

    Lamb, Tracey J

    2012-01-01

    ... 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...

  17. Lifestyle and dietary factors in the prevention of lethal prostate cancer

    Science.gov (United States)

    Wilson, Kathryn M; Giovannucci, Edward L; Mucci, Lorelei A

    2012-01-01

    The prevention of lethal prostate cancer is a critical public health challenge that would improve health and reduce suffering from this disease. In this review, we discuss the evidence surrounding specific lifestyle and dietary factors in the prevention of lethal prostate cancer. We present a summary of evidence for the following selected behavioral risk factors: obesity and weight change, physical activity, smoking, antioxidant intake, vitamin D and calcium, and coffee intake. PMID:22504869

  18. Lifestyle and dietary factors in the prevention of lethal prostate cancer

    Institute of Scientific and Technical Information of China (English)

    Kathryn M Wilson; Edward L Giovannucci; Lorelei A Mucci

    2012-01-01

    The prevention of lethal prostate cancer is a critical public health challenge that would improve health and reduce suffering from this disease.In this review,we discuss the evidence surrounding specific lifestyle and dietary factors in the prevention of lethal prostate cancer.We present a summary of evidence for the following selected behavioral risk factors:obesity and weight change,physical activity,smoking,antioxidant intake,vitamin D and calcium,and coffee intake.

  19. The Contribution of Immune Evasive Mechanisms to Parasite Persistence in Visceral Leishmaniasis

    Science.gov (United States)

    de Freitas, Elisangela Oliveira; Leoratti, Fabiana Maria de Souza; Freire-de-Lima, Célio Geraldo; Morrot, Alexandre; Feijó, Daniel Ferreira

    2016-01-01

    Leishmania is a genus of protozoan parasites that give rise to a range of diseases called Leishmaniasis that affects annually an estimated 1.3 million people from 88 countries. Leishmania donovani and Leishmania (L.) infantum chagasi are responsible to cause the visceral leishmaniasis. The parasite can use assorted strategies to interfere with the host homeostasis to establish persistent infections that without treatment can be lethal. In this review, we highlight the mechanisms involved in the parasite subversion of the host protective immune response and how alterations of host tissue physiology and vascular remodeling during VL could affect the organ-specific immunity against Leishmania parasites. PMID:27148272

  20. Effects of lethal and non-lethal malaria on the mononuclear phagocyte system

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Tosta

    1983-03-01

    Full Text Available The effects ofone non-lethal species ofmalarialparasite, Plasmodium yoelii, and one lethal species, P. berghei, on the mononuclear phagocyte system (MPS of BALB/c mice were studied. P. yoelii caused a greater and more sustained expansion and activation of the MPS, and the two major populations of spleen phagocytic cells-red pulp and marginal zone macrophages - exhibited a greater increase in numbers in this infection. During the course of P. berghei mataria, the spleen was progressively occupied by haematopoietic tissue and, at the terminal stage of infection, an extensive depletion of lymphocytes and macrophages was apparent. The possibility was suggested that the outcome of mataria may be inftuenced by the particular way the parasite interacts with the MPS.Estudou-se o efeito da infecção causada por espécie letal (Plasmodium berghei e não- letal (P. yoelii de plasmódio sobre o sistema de fagócitos mononucleares de camundongo BALB/c. O P. yoelii causou maior e mais prolongada expansão e ativação do sistema de macrófagos. As duas mais importantes populações de fagócitos esplênicos - macrófagos de polpa vermelha e da zona marginal - exibiam maior aumento do número de células nesta infecção. Durante a evolução da malária por P. berghei, o baço foi progressivamente ocupado por tecido hematopoiético e, na fase terminal da infecção, observou-se significativa depleção dos linfócitos e macrófagos esplênicos. Os dados apresentados indicam que a evolução da malária depende do tipo de interação entre o plasmódio e o sistema de fagócitos mononucleares.

  1. Lethal entanglement in baleen whales.

    Science.gov (United States)

    Cassoff, Rachel M; Moore, Kathleen M; McLellan, William A; Barco, Susan G; Rotsteins, David S; Moore, Michael J

    2011-10-06

    Understanding the scenarios whereby fishing gear entanglement of large whales induces mortality is important for the development of mitigation strategies. Here we present a series of 21 cases involving 4 species of baleen whales in the NW Atlantic, describing the available sighting history, necropsy observations, and subsequent data analyses that enabled the compilation of the manners in which entanglement can be lethal. The single acute cause of entanglement mortality identified was drowning from entanglement involving multiple body parts, with the animal's inability to surface. More protracted causes of death included impaired foraging during entanglement, resulting in starvation after many months; systemic infection arising from open, unresolved entanglement wounds; and hemorrhage or debilitation due to severe gear-related damage to tissues. Serious gear-induced injury can include laceration of large vessels, occlusion of the nares, embedding of line in growing bone, and massive periosteal proliferation of new bone in an attempt to wall off constricting, encircling lines. These data show that baleen whale entanglement is not only a major issue for the conservation of some baleen whale populations, but is also a major concern for the welfare of each affected individual.

  2. Parasites: evolution's neurobiologists.

    Science.gov (United States)

    Adamo, Shelley Anne

    2013-01-01

    For millions of years, parasites have altered the behaviour of their hosts. Parasites can affect host behaviour by: (1) interfering with the host's normal immune-neural communication, (2) secreting substances that directly alter neuronal activity via non-genomic mechanisms and (3) inducing genomic- and/or proteomic-based changes in the brain of the host. Changes in host behaviour are often restricted to particular behaviours, with many other behaviours remaining unaffected. Neuroscientists can produce this degree of selectivity by targeting specific brain areas. Parasites, however, do not selectively attack discrete brain areas. Parasites typically induce a variety of effects in several parts of the brain. Parasitic manipulation of host behaviour evolved within the context of the manipulation of other host physiological systems (especially the immune system) that was required for a parasite's survival. This starting point, coupled with the fortuitous nature of evolutionary innovation and evolutionary pressures to minimize the costs of parasitic manipulation, likely contributed to the complex and indirect nature of the mechanisms involved in host behavioural control. Because parasites and neuroscientists use different tactics to control behaviour, studying the methods used by parasites can provide novel insights into how nervous systems generate and regulate behaviour. Studying how parasites influence host behaviour will also help us integrate genomic, proteomic and neurophysiological perspectives on behaviour.

  3. Cystatins of parasitic organisms.

    Science.gov (United States)

    Klotz, Christian; Ziegler, Thomas; Daniłowicz-Luebert, Emilia; Hartmann, Susanne

    2011-01-01

    The cystatin superfamily comprises several groups of protease inhibitors. In this chapter we will focus on I25 family members, which consist predominantly of the type 2 cystatins. Recently, a wealth of information on these molecules and their activities has been described. Parasite cystatins are shown to have dual functions via interaction with both parasite and host proteases. Thereby, parasite cystatins are not only essentially involved in the regulation of physiological processes during parasite development, but also represent important pathogenicity factors. Interestingly, some studies indicate that parasite cystatins evolved exceptional immuno-modulatory properties. these capacities could be exploited to interfere with unwanted immune responses in unrelated human inflammatory diseases. We highlight the different biological roles of parasite cystatins and the anticipated future developments.

  4. 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....

  5. 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.

  6. 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.

  7. Parasites resistant to the antimalarial atovaquone fail to transmit by mosquitoes.

    Science.gov (United States)

    Goodman, Christopher D; Siregar, Josephine E; Mollard, Vanessa; Vega-Rodríguez, Joel; Syafruddin, Din; Matsuoka, Hiroyuki; Matsuzaki, Motomichi; Toyama, Tomoko; Sturm, Angelika; Cozijnsen, Anton; Jacobs-Lorena, Marcelo; Kita, Kiyoshi; Marzuki, Sangkot; McFadden, Geoffrey I

    2016-04-15

    Drug resistance compromises control of malaria. Here, we show that resistance to a commonly used antimalarial medication, atovaquone, is apparently unable to spread. Atovaquone pressure selects parasites with mutations in cytochrome b, a respiratory protein with low but essential activity in the mammalian blood phase of the parasite life cycle. Resistance mutations rescue parasites from the drug but later prove lethal in the mosquito phase, where parasites require full respiration. Unable to respire efficiently, resistant parasites fail to complete mosquito development, arresting their life cycle. Because cytochrome b is encoded by the maternally inherited parasite mitochondrion, even outcrossing with wild-type strains cannot facilitate spread of resistance. Lack of transmission suggests that resistance will be unable to spread in the field, greatly enhancing the utility of atovaquone in malaria control. Copyright © 2016, American Association for the Advancement of Science.

  8. Parasites and marine invasions

    Science.gov (United States)

    Torchin, M.E.; Lafferty, K.D.; Kuris, A.M.

    2002-01-01

    Introduced marine species are a major environmental and economic problem. The rate of these biological invasions has substantially increased in recent years due to the globalization of the world's economies. The damage caused by invasive species is often a result of the higher densities and larger sizes they attain compared to where they are native. A prominent hypothesis explaining the success of introduced species is that they are relatively free of the effects of natural enemies. Most notably, they may encounter fewer parasites in their introduced range compared to their native range. Parasites are ubiquitous and pervasive in marine systems, yet their role in marine invasions is relatively unexplored. Although data on parasites of marine organisms exist, the extent to which parasites can mediate marine invasions, or the extent to which invasive parasites and pathogens are responsible for infecting or potentially decimating native marine species have not been examined. In this review, we present a theoretical framework to model invasion success and examine the evidence for a relationship between parasite presence and the success of introduced marine species. For this, we compare the prevalence and species richness of parasites in several introduced populations of marine species with populations where they are native. We also discuss the potential impacts of introduced marine parasites on native ecosystems.

  9. 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...

  10. 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....

  11. Parasite infections revisited

    NARCIS (Netherlands)

    Wiegertjes, G.F.; Forlenza, M.; Joerink, M.; Scharsack, J.P.

    2005-01-01

    Studying parasites helps reveal basic mechanisms in immunology. For long this has been recognized for studies on the immune system of mice and man. But it is not true for immunological studies on fish. To support this argument we discuss selected examples of parasite infections not only in warm-bloo

  12. Experimental aerosolized guinea pig-adapted Zaire ebolavirus (variant: Mayinga) causes lethal pneumonia in guinea pigs.

    Science.gov (United States)

    Twenhafel, N A; Shaia, C I; Bunton, T E; Shamblin, J D; Wollen, S E; Pitt, L M; Sizemore, D R; Ogg, M M; Johnston, S C

    2015-01-01

    Eight guinea pigs were aerosolized with guinea pig-adapted Zaire ebolavirus (variant: Mayinga) and developed lethal interstitial pneumonia that was distinct from lesions described in guinea pigs challenged subcutaneously, nonhuman primates challenged by the aerosol route, and natural infection in humans. Guinea pigs succumbed with significant pathologic changes primarily restricted to the lungs. Intracytoplasmic inclusion bodies were observed in many alveolar macrophages. Perivasculitis was noted within the lungs. These changes are unlike those of documented subcutaneously challenged guinea pigs and aerosolized filoviral infections in nonhuman primates and human cases. Similar to findings in subcutaneously challenged guinea pigs, there were only mild lesions in the liver and spleen. To our knowledge, this is the first report of aerosol challenge of guinea pigs with guinea pig-adapted Zaire ebolavirus (variant: Mayinga). Before choosing this model for use in aerosolized ebolavirus studies, scientists and pathologists should be aware that aerosolized guinea pig-adapted Zaire ebolavirus (variant: Mayinga) causes lethal pneumonia in guinea pigs.

  13. AIDS - associated parasitic diarrhoea

    Directory of Open Access Journals (Sweden)

    Arora D

    2009-01-01

    Full Text Available Since the advent of human immunodeficiency virus infection, with its profound and progressive effect on the cellular immune system, a group of human opportunistic pathogens has come into prominence. Opportunistic parasitic infection can cause severe morbidity and mortality. Because many of these infections are treatable, an early and accurate diagnosis is important. This can be accomplished by a variety of methods such as direct demonstration of parasites and by serological tests to detect antigen and/or specific antibodies. However, antibody response may be poor in these patients and therefore immunodiagnostic tests have to be interpreted with caution. Cryptosporidium parvum , Isospora belli , Cyclospora cayetanensis , Microsporidia, Entamoeba histolytica and Strongyloides stercoralis are the commonly detected parasites. Detection of these parasites will help in proper management of these patients because drugs are available for most of these parasitic infections.

  14. The effect and relative importance of neutral genetic diversity for predicting parasitism varies across parasite taxa.

    Directory of Open Access Journals (Sweden)

    María José Ruiz-López

    Full Text Available Understanding factors that determine heterogeneity in levels of parasitism across individuals is a major challenge in disease ecology. It is known that genetic makeup plays an important role in infection likelihood, but the mechanism remains unclear as does its relative importance when compared to other factors. We analyzed relationships between genetic diversity and macroparasites in outbred, free-ranging populations of raccoons (Procyon lotor. We measured heterozygosity at 14 microsatellite loci and modeled the effects of both multi-locus and single-locus heterozygosity on parasitism using an information theoretic approach and including non-genetic factors that are known to influence the likelihood of parasitism. The association of genetic diversity and parasitism, as well as the relative importance of genetic diversity, differed by parasitic group. Endoparasite species richness was better predicted by a model that included genetic diversity, with the more heterozygous hosts harboring fewer endoparasite species. Genetic diversity was also important in predicting abundance of replete ticks (Dermacentor variabilis. This association fit a curvilinear trend, with hosts that had either high or low levels of heterozygosity harboring fewer parasites than those with intermediate levels. In contrast, genetic diversity was not important in predicting abundance of non-replete ticks and lice (Trichodectes octomaculatus. No strong single-locus effects were observed for either endoparasites or replete ticks. Our results suggest that in outbred populations multi-locus diversity might be important for coping with parasitism. The differences in the relationships between heterozygosity and parasitism for the different parasites suggest that the role of genetic diversity varies with parasite-mediated selective pressures.

  15. ULCERATIVE AND NECROTIZING GASTRITIS IN A CAPTIVE SLOTH (BRADYPUS VARIEGATUS, XENARTHRA, BRADYPODIDAE) DUE TO SEVERE PARASITISM WITH PARALEIURIS LOCCHII (NEMATODA, SPIROCERCIDAE).

    Science.gov (United States)

    Michel, Ana Flávia Ribeiro Machado; Silva, Fabiana Lessa; Barbosa, Fernando Sérgio; de Carvalho, Tatiane Furtado; Pinto, Jaqueline Maria Silva; Santos, Renato Lima

    2017-03-01

    This is the first reported case of lethal gastric parasitism by the nematode Paraleiuris locchii in a captive sloth ( Bradypus variegatus ). There were more than 600 parasites in the stomach of the sloth, associated with extensive areas of ulceration and necrosis. The animal developed emaciation, dehydration, and anemia that progressed to death.

  16. Lysine Deacetylase Inhibitors in Parasites: Past, Present, and Future Perspectives.

    Science.gov (United States)

    Hailu, Gebremedhin S; Robaa, Dina; Forgione, Mariantonietta; Sippl, Wolfgang; Rotili, Dante; Mai, Antonello

    2017-06-22

    Current therapies for human parasite infections rely on a few drugs, most of which have severe side effects, and their helpfulness is being seriously compromised by the drug resistance problem. Globally, this is pushing discovery research of antiparasitic drugs toward new agents endowed with new mechanisms of action. By using a "drug repurposing" strategy, histone deacetylase inhibitors (HDACi), which are presently clinically approved for cancer use, are now under investigation for various parasite infections. Because parasitic Zn(2+)- and NAD(+)-dependent HDACs play crucial roles in the modulation of parasite gene expression and many of them are pro-survival for several parasites under various conditions, they are now emerging as novel potential antiparasitic targets. This Perspective summarizes the state of knowledge of HDACi (both class I/II HDACi and sirtuin inhibitors) targeted to the main human parasitic diseases (schistosomiasis, malaria, trypanosomiasis, leishmaniasis, and toxoplasmosis) and provides visions into the main issues that challenge their development as antiparasitic agents.

  17. Caenorhabditis elegans: A Genetic Guide to Parasitic Nematode Biology.

    Science.gov (United States)

    Bird, D M; Opperman, C H

    1998-09-01

    The advent of parasite genome sequencing projects, as well as an increase in biology-directed gene discovery, promises to reveal genes encoding many of the key molecules required for nematode-host interactions. However, distinguishing parasitism genes from those merely required for nematode viability remains a substantial challenge. Although this will ultimately require a functional test in the host or parasite, the free-living nematode Caenorhabditis elegans can be exploited as a heterologous system to determine function of candidate parasitism genes. Studies of C. elegans also have revealed genetic networks, such as the dauer pathway, that may also be important adaptations for parasitism. As a more directed means of identifying parasitism traits, we developed classical genetics for Heterodera glycines and have used this approach to map genes conferring host resistance-breaking phenotypes. It is likely that the C. elegans and H. glycines genomes will be at least partially syntenic, thus permitting predictive physical mapping of H. glycines genes of interest.

  18. Parasitic diseases in travelers: a focus on therapy.

    Science.gov (United States)

    Showler, Adrienne J; Wilson, Mary E; Kain, Kevin C; Boggild, Andrea K

    2014-04-01

    Parasitic infections are an important cause of illness among returned travelers, and can lead to considerable morbidity and, in some cases, mortality. The complexity of parasitic life cycles and geographic specificities can present diagnostic challenges, particularly in non-endemic settings to which most travelers return for care. Clinical manifestations reflect the diverse taxonomy and pathogenesis of parasites, and appropriate diagnosis and management therefore necessitate a high index of suspicion of parasitic illnesses. Much of our knowledge surrounding management of parasitic infections in travelers is extrapolated from evidence derived in endemic populations, or is based on expert opinion and case series. We herein provide an overview of parasitic diseases of short-term travelers, and summarize current therapeutic strategies for each illness.

  19. Platelets kill intraerythrocytic malarial parasites and mediate survival to infection.

    Science.gov (United States)

    McMorran, Brendan J; Marshall, Vikki M; de Graaf, Carolyn; Drysdale, Karen E; Shabbar, Meriam; Smyth, Gordon K; Corbin, Jason E; Alexander, Warren S; Foote, Simon J

    2009-02-01

    Platelets play a critical role in the pathogenesis of malarial infections by encouraging the sequestration of infected red blood cells within the cerebral vasculature. But platelets also have well-established roles in innate protection against microbial infections. We found that purified human platelets killed Plasmodium falciparum parasites cultured in red blood cells. Inhibition of platelet function by aspirin and other platelet inhibitors abrogated the lethal effect human platelets exert on P. falciparum parasites. Likewise, platelet-deficient and aspirin-treated mice were more susceptible to death during erythrocytic infection with Plasmodium chabaudi. Both mouse and human platelets bind malarial-infected red cells and kill the parasite within. These results indicate a protective function for platelets in the early stages of erythrocytic infection distinct from their role in cerebral malaria.

  20. Suppressive effects of anthrax lethal toxin on megakaryopoiesis.

    Directory of Open Access Journals (Sweden)

    Po-Kong Chen

    Full Text Available Anthrax lethal toxin (LT is a major virulence factor of Bacillus anthracis. LT challenge suppresses platelet counts and platelet function in mice, however, the mechanism responsible for thrombocytopenia remains unclear. LT inhibits cellular mitogen-activated protein kinases (MAPKs, which are vital pathways responsible for cell survival, differentiation, and maturation. One of the MAPKs, the MEK1/2-extracellular signal-regulated kinase pathway, is particularly important in megakaryopoiesis. This study evaluates the hypothesis that LT may suppress the progenitor cells of platelets, thereby inducing thrombocytopenic responses. Using cord blood-derived CD34(+ cells and mouse bone marrow mononuclear cells to perform in vitro differentiation, this work shows that LT suppresses megakaryopoiesis by reducing the survival of megakaryocytes. Thrombopoietin treatments can reduce thrombocytopenia, megakaryocytic suppression, and the quick onset of lethality in LT-challenged mice. These results suggest that megakaryocytic suppression is one of the mechanisms by which LT induces thrombocytopenia. These findings may provide new insights for developing feasible approaches against anthrax.

  1. Ongoing challenges in the management of malaria.

    Science.gov (United States)

    Kokwaro, Gilbert

    2009-10-12

    This article gives an overview of some of the ongoing challenges that are faced in the prevention, diagnosis and treatment of malaria. Malaria causes approximately 881,000 deaths every year, with nine out of ten deaths occurring in sub-Saharan Africa. In addition to the human burden of malaria, the economic burden is vast. It is thought to cost African countries more than US$12 billion every year in direct losses. However, great progress in malaria control has been made in some highly endemic countries. Vector control is assuming a new importance with the significant reductions in malaria burden achieved using combined malaria control interventions in countries such as Zanzibar, Zambia and Rwanda. The proportion of patients treated for malaria who have a confirmed diagnosis is low in Africa compared with other regions of the world, with the result that anti-malarials could be used to treat patients without malaria, especially in areas where progress has been made in reducing the malaria burden and malaria epidemiology is changing. Inappropriate administration of anti-malarials could contribute to the spread of resistance and incurs unnecessary costs. Parasite resistance to almost all commonly used anti-malarials has been observed in the most lethal parasite species, Plasmodium falciparum. This has presented a major barrier to successful disease management in malaria-endemic areas. ACT (artemisinin-based combination therapy) has made a significant contribution to malaria control and to reducing disease transmission through reducing gametocyte carriage. Administering ACT to infants and small children can be difficult and time consuming. Specially formulating anti-malarials for this vulnerable population is vital to ease administration and help ensure that an accurate dose is received. Education of healthworkers and communities about malaria prevention, diagnosis and treatment is a vital component of effective case management, especially as diagnostic policies change

  2. The helminth parasite proteome at the host-parasite interface - Informing diagnosis and control.

    Science.gov (United States)

    van der Ree, Anna M; Mutapi, Francisca

    2015-10-01

    Helminth parasites are a significant health burden for humans in the developing world and also cause substantial economic losses in livestock production across the world. The combined lack of vaccines for the major human and veterinary helminth parasites in addition to the development of drug resistance to anthelmintics in sheep and cattle mean that controlling helminth infection and pathology remains a challenge. However, recent high throughput technological advances mean that screening for potential drug and vaccine candidates is now easier than in previous decades. A better understanding of the host-parasite interactions occurring during infection and pathology and identifying pathways that can be therapeutically targeted for more effective and 'evolution proof' interventions is now required. This review highlights some of the advances that have been made in understanding the host-parasite interface in helminth infections using studies of the temporal expression of parasite proteins, i.e. the parasite proteome, and discuss areas for potential future research and translation.

  3. Lethality Index 2008-2014: Less shootings, same lethality, more opacity

    Directory of Open Access Journals (Sweden)

    Carlos Silva Forné

    2017-07-01

    Full Text Available This article evaluates the use of lethal force by Mexican federal security forces during shootings with presumed members of organized crime from 2008-2014. The authors use official data and press reports on deaths and wounded in shootings to construct indicators such as the number of dead civilians over the number of dead officials from the federal security forces and the number of dead civilians over the number of wounded civilians. In a context where certain factors that contribute to an excessive use of force become more common, the results of the study show a growing use of lethal force. This raises questions over the possible excessive use of lethal force as a normal or systematic practice. The study also shows a growing context of opacity in the infor­mation available to evaluate the use of lethal force and the general lack of a legal framework to regulate the use of lethal force in Mexico.

  4. [Parasitism and ecological parasitology].

    Science.gov (United States)

    Balashov, Iu S

    2011-01-01

    Parasitism as one of the life modes is a general biological phenomenon and is a characteristic of all viruses, many taxa of bacteria, fungi, protists, metaphytes, and metazoans. Zooparasitology is focused on studies of parasitic animals, particularly, on their taxonomy, anatomy, life cycles, host-parasite relations, biocoenotic connections, and evolution. Ecological parasitology is a component of ecology, as the scientific study of the relation of living organisms with each other and their surroundings. In the present paper, critical analysis of the problems, main postulates, and terminology of the modern ecological parasitology is given.

  5. The Receptors that Mediate the Direct Lethality of Anthrax Toxin

    Directory of Open Access Journals (Sweden)

    Stephen H. Leppla

    2012-12-01

    Full Text Available Tumor endothelium marker-8 (TEM8 and capillary morphogenesis protein-2 (CMG2 are the two well-characterized anthrax toxin receptors, each containing a von Willebrand factor A (vWA domain responsible for anthrax protective antigen (PA binding. Recently, a cell-based analysis was used to implicate another vWA domain-containing protein, integrin β1 as a third anthrax toxin receptor. To explore whether proteins other than TEM8 and CMG2 function as anthrax toxin receptors in vivo, we challenged mice lacking TEM8 and/or CMG2. Specifically, we used as an effector protein the fusion protein FP59, a fusion between the PA-binding domain of anthrax lethal factor (LF and the catalytic domain of Pseudomonas aeruginosa exotoxin A. FP59 is at least 50-fold more potent than LF in the presence of PA, with 2 μg PA + 2 μg FP59 being sufficient to kill a mouse. While TEM8−/− and wild type control mice succumbed to a 5 μg PA + 5 μg FP59 challenge, CMG2−/− mice were completely resistant to this dose, confirming that CMG2 is the major anthrax toxin receptor in vivo. To detect whether any toxic effects are mediated by TEM8 or other putative receptors such as integrin β1, CMG2−/−/TEM8−/− mice were challenged with as many as five doses of 50 μg PA + 50 μg FP59. Strikingly, the CMG2−/−/TEM8−/− mice were completely resistant to the 5-dose challenge. These results strongly suggest that TEM8 is the only minor anthrax toxin receptor mediating direct lethality in vivo and that other proteins implicated as receptors do not play this role.

  6. Metabolomics and protozoan parasites.

    Science.gov (United States)

    Paget, Timothy; Haroune, Nicolas; Bagchi, Sushmita; Jarroll, Edward

    2013-06-01

    In this review, we examine the state-of-the-art technologies (gas and liquid chromatography, mass spectroscopy and nuclear magnetic resonance, etc.) in the well-established area of metabolomics especially as they relate to protozoan parasites.

  7. Transfection of malaria parasites.

    Science.gov (United States)

    Waters, A P; Thomas, A W; van Dijk, M R; Janse, C J

    1997-10-01

    The stable genetic transformation of three phylogenetically diverse species of Plasmodium, the parasitic etiological agent of malaria, is now possible. The parasite is haploid throughout the vast majority of its life cycle. Therefore with the single selectable marker activity and protocols currently available, it is possible not only to express introduced transgenes but also to study the effects of site-specific homologous recombination such as gene knockout. Transgene expression will allow the detailed study of many aspects of the cellular biology of malaria parasites, for example, the mechanisms underlying drug resistance and protein trafficking. We describe here the methods for propagation of the two animal models (Plasmodium berghei and Plasmodium knowlesi) and for transfection of these two species and the human parasite, Plasmodium falciparum. Examples of transgene expression are given.

  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. Management of Strongyloides stercoralis: a puzzling parasite.

    Science.gov (United States)

    Luvira, Viravarn; Watthanakulpanich, Dorn; Pittisuttithum, Punnee

    2014-12-01

    Strongyloides stercoralis is one of the common parasites in tropical areas. It can result in severe clinical syndromes, hyperinfection syndrome or disseminated strongyloidiasis in immunocompromised patients. The treatment of strongyloidiasis is a challenge for clinicians in clinical practice. Failure of treatment is due to autoinfection caused by the parasite life cycle and impairment of host immunity. Ivermectin currently is the treatment of choice. When compared with thiabendazole, it has shown a similar efficacy with better tolerability. However, there is neither consensus in duration of treatment nor in repetition of doses. The keys for management of this tough parasite include proper evaluation and prevention. Stool examination with high sensitivity techniques such as Baermann technique, filter-paper culture and agar-plate culture and specific IgG serology should be used in evaluation for 1 to 2 years. Screening, both stool examination and serology, before patients have immunosuppressive treatment is needed to prevent the severe form of strongyloidiasis.

  10. Parasites and human evolution.

    Science.gov (United States)

    Perry, George H

    2014-01-01

    Our understanding of human evolutionary and population history can be advanced by ecological and evolutionary studies of our parasites. Many parasites flourish only in the presence of very specific human behaviors and in specific habitats, are wholly dependent on us, and have evolved with us for thousands or millions of years. Therefore, by asking when and how we first acquired those parasites, under which environmental and cultural conditions we are the most susceptible, and how the parasites have evolved and adapted to us and we in response to them, we can gain considerable insight into our own evolutionary history. As examples, the tapeworm life cycle is dependent on our consumption of meat, the divergence of body and head lice may have been subsequent to the development of clothing, and malaria hyperendemicity may be associated with agriculture. Thus, the evolutionary and population histories of these parasites are likely intertwined with critical aspects of human biology and culture. Here I review the mechanics of these and multiple other parasite proxies for human evolutionary history and discuss how they currently complement our fossil, archeological, molecular, linguistic, historical, and ethnographic records. I also highlight potential future applications of this promising model for the field of evolutionary anthropology.

  11. 5-Lipoxygenase Deficiency Reduces Acetaminophen-Induced Hepatotoxicity and Lethality

    Directory of Open Access Journals (Sweden)

    Miriam S. N. Hohmann

    2013-01-01

    Full Text Available 5-Lipoxygenase (5-LO converts arachidonic acid into leukotrienes (LTs and is involved in inflammation. At present, the participation of 5-LO in acetaminophen (APAP-induced hepatotoxicity and liver damage has not been addressed. 5-LO deficient (5-LO-/- mice and background wild type mice were challenged with APAP (0.3–6 g/kg or saline. The lethality, liver damage, neutrophil and macrophage recruitment, LTB4, cytokine production, and oxidative stress were assessed. APAP induced a dose-dependent mortality, and the dose of 3 g/kg was selected for next experiments. APAP induced LTB4 production in the liver, the primary target organ in APAP toxicity. Histopathological analysis revealed that 5-LO-/- mice presented reduced APAP-induced liver necrosis and inflammation compared with WT mice. APAP-induced lethality, increase of plasma levels of aspartate aminotransferase and alanine aminotransferase, liver cytokine (IL-1β, TNF-α, IFN-γ, and IL-10, superoxide anion, and thiobarbituric acid reactive substances production, myeloperoxidase and N-acetyl-β-D-glucosaminidase activity, Nrf2 and gp91phox mRNA expression, and decrease of reduced glutathione and antioxidant capacity measured by 2,2′-azinobis(3-ethylbenzothiazoline 6-sulfonate assay were prevented in 5-LO-/- mice compared to WT mice. Therefore, 5-LO deficiency resulted in reduced mortality due to reduced liver inflammatory and oxidative damage, suggesting 5-LO is a promising target to reduce APAP-induced lethality and liver inflammatory/oxidative damage.

  12. 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.

  13. Guidebook for non-lethal experimentation

    NARCIS (Netherlands)

    Paulissen, J.J.M.; Rahimi, R.

    2011-01-01

    In the 2009-2011 timeframe, NATO conducts a capability based assessment of Non-Lethal Weapon (NLW) systems. The work, performed by the RTO study team SAS-078, involves the development of NLW requirement descriptions, which are put against a set of NLW systems. Gaps are likely to occur, indicating th

  14. Flagellar motility in eukaryotic human parasites.

    Science.gov (United States)

    Krüger, Timothy; Engstler, Markus

    2015-10-01

    A huge variety of protists rely on one or more motile flagella to either move themselves or move fluids and substances around them. Many of these flagellates have evolved a symbiotic or parasitic lifestyle. Several of the parasites have adapted to human hosts, and include agents of prevalent and serious diseases. These unicellular parasites have become specialised in colonising a wide range of biological niches within humans. They usually have diverse transmission cycles, and frequently manifest a variety of distinct morphological stages. The motility of the single or multiple flagella plays important but understudied roles in parasite transmission, host invasion, dispersal, survival, proliferation and pathology. In this review we provide an overview of the important human pathogens that possess a motile flagellum for at least part of their life cycle. We highlight recently published studies that aim to elucidate motility mechanisms, and their relevance for human disease. We then bring the physics of swimming at the microscale into context, emphasising the importance of interdisciplinary approaches for a full understanding of flagellate motility - especially in light of the parasites' microenvironments and population dynamics. Finally, we summarise some important technological aspects, describing challenges for the field and possibilities for motility analyses in the future.

  15. Parasitic nematodes - from genomes to control.

    Science.gov (United States)

    Mitreva, Makedonka; Zarlenga, Dante S; McCarter, James P; Jasmer, Douglas P

    2007-08-19

    The diseases caused by parasitic nematodes in domestic and companion animals are major factors that decrease production and quality of the agricultural products. Methods available for the control of the parasitic nematode infections are mainly based on chemical treatment, non-chemical management practices, immune modulation and biological control. However, even with integrated pest management that frequently combines these approaches, the effective and long-lasting control strategies are hampered by the persistent exposure of host animals to environmental stages of parasites, the incomplete protective response of the host and acquisition of anthelmintic resistance by an increasing number of parasitic nematodes. Therefore, the challenges to improve control of parasitic nematode infections are multi-fold and no single category of information will meet them all. However, new information, such as nematode genomics, functional genomics and proteomics, can strengthen basic and applied biological research aimed to develop improvements. In this review we will, summarize existing control strategies of nematode infections and discuss ongoing developments in nematode genomics. Genomics approaches offer a growing and fundamental base of information, which when coupled with downstream functional genomics and proteomics can accelerate progress towards developing more efficient and sustainable control programs.

  16. Testing of candidate non-lethal sampling methods for detection of Renibacterium salmoninarum in juvenile Chinook salmon Oncorhynchus tshawytscha

    Science.gov (United States)

    Elliott, Diane G.; McKibben, Constance L.; Conway, Carla M.; Purcell, Maureen K.; Chase, Dorothy M.; Applegate, Lynn M.

    2015-01-01

    Non-lethal pathogen testing can be a useful tool for fish disease research and management. Our research objectives were to determine if (1) fin clips, gill snips, surface mucus scrapings, blood draws, or kidney biopsies could be obtained non-lethally from 3 to 15 g Chinook salmon Oncorhynchus tshawytscha, (2) non-lethal samples could accurately discriminate between fish exposed to the bacterial kidney disease agent Renibacterium salmoninarum and non-exposed fish, and (3) non-lethal samples could serve as proxies for lethal kidney samples to assess infection intensity. Blood draws and kidney biopsies caused ≥5% post-sampling mortality (Objective 1) and may be appropriate only for larger fish, but the other sample types were non-lethal. Sampling was performed over 21 wk following R. salmoninarum immersion challenge of fish from 2 stocks (Objectives 2 and 3), and nested PCR (nPCR) and real-time quantitative PCR (qPCR) results from candidate non-lethal samples were compared with kidney tissue analysis by nPCR, qPCR, bacteriological culture, enzyme-linked immunosorbent assay (ELISA), fluorescent antibody test (FAT) and histopathology/immunohistochemistry. R. salmoninarum was detected by PCR in >50% of fin, gill, and mucus samples from challenged fish. Mucus qPCR was the only non-lethal assay exhibiting both diagnostic sensitivity and specificity estimates >90% for distinguishing between R. salmoninarum-exposed and non-exposed fish and was the best candidate for use as an alternative to lethal kidney sample testing. Mucus qPCR R. salmoninarum quantity estimates reflected changes in kidney bacterial load estimates, as evidenced by significant positive correlations with kidney R. salmoninaruminfection intensity scores at all sample times and in both fish stocks, and were not significantly impacted by environmentalR. salmoninarum concentrations.

  17. Cholesterol Metabolism and Prostate Cancer Lethality.

    Science.gov (United States)

    Stopsack, Konrad H; Gerke, Travis A; Sinnott, Jennifer A; Penney, Kathryn L; Tyekucheva, Svitlana; Sesso, Howard D; Andersson, Swen-Olof; Andrén, Ove; Cerhan, James R; Giovannucci, Edward L; Mucci, Lorelei A; Rider, Jennifer R

    2016-08-15

    Cholesterol metabolism has been implicated in prostate cancer pathogenesis. Here, we assessed the association of intratumoral mRNA expression of cholesterol synthesis enzymes, transporters, and regulators in tumor specimen at diagnosis and lethal prostate cancer, defined as mortality or metastases from prostate cancer in contrast to nonlethal disease without evidence of metastases after at least 8 years of follow-up. We analyzed the prospective prostate cancer cohorts within the Health Professionals Follow-up Study (n = 249) and the Physicians' Health Study (n = 153) as well as expectantly managed patients in the Swedish Watchful Waiting Study (n = 338). The expression of squalene monooxygenase (SQLE) was associated with lethal cancer in all three cohorts. Men with high SQLE expression (>1 standard deviation above the mean) were 8.3 times (95% confidence interval, 3.5 to 19.7) more likely to have lethal cancer despite therapy compared with men with the mean level of SQLE expression. Absolute SQLE expression was associated with lethal cancer independently from Gleason grade and stage, as was a SQLE expression ratio in tumor versus surrounding benign prostate tissue. Higher SQLE expression was tightly associated with increased histologic markers of angiogenesis. Collectively, this study establishes the prognostic value of intratumoral cholesterol synthesis as measured via SQLE, its second rate-limiting enzyme. SQLE expression at cancer diagnosis is prognostic for lethal prostate cancer both after curative-intent prostatectomy and in a watchful waiting setting, possibly by facilitating micrometastatic disease. Cancer Res; 76(16); 4785-90. ©2016 AACR.

  18. Invasive plants as catalysts for the spread of human parasites

    Directory of Open Access Journals (Sweden)

    Richard Mack

    2011-08-01

    Full Text Available As serious as are the consequences of invasive species that directly cause human afflictions through their production of lethal protease inhibitors (Bryonia alba, allergens (Parthenium hysterophorus or furanocoumarins (Hercaleum mantegazzianum, other introduced species may cause even greater risks to human health by enhancing the proliferation of vectors of virulent human parasites. The dense, floating mats of Eichhornia crassipes (water hyacinth create habitat for larvae of the dipteran vectors of Plasmodium spp., the causative agents of malaria, and other parasites. Facilitation of a human parasite is not restricted to aquatic systems. In Africa, the tropical American shrub Lantana camara (lantana provides essential habitat for dipteran vectors (Glossina spp. of protozoans (Trypanosoma spp. that cause trypanosomiasis. Unanticipated health consequences will likely continue to emerge from new plant introductions. Sin Nombre Virus (SNV is a rodent-borne parasite that causes Hantavirus Pulmonary Syndrome, an often-lethal disease in humans. Populations of rodent vectors of SNV in South America increase rapidly in response to synchronous fruit availability among masting, native bamboos. With depletion of this temporary food source, the rodents seek food near human settlements, increasing the risk of human infections with SNV. In the United States the omnivorous deer mouse Peromyscus maniculatus is also a SNV carrier. The escape of Asian cold-tolerant bamboos from cultivation raises the possibility of invasions (several have already become naturalized and providing a temporary boost to populations of infected native rodents. Proposed introductions of aquatic vascular species, species with masting reproduction and those that would occupy an unfilled niche in the proposed new range deserve careful evaluation for their possible roles as unforeseen catalysts of species interactions, especially of human parasites.

  19. Plants, endosymbionts and parasites: Abscisic acid and calcium signaling.

    Science.gov (United States)

    Nagamune, Kisaburo; Xiong, Liming; Chini, Eduardo; Sibley, L David

    2008-01-01

    It was recently discovered that the protozoan parasite, Toxoplasma gondii produces and uses the plant hormone, abscisic acid (ABA), for communication. Following intracellular replication, ABA production influences the timing of parasite egress from the host cell. This density-dependent signal may serve to coordinate exit from the host cell in a synchronous manner by triggering calcium-dependent activation of motility. In the absence of ABA production, parasites undergo differentiation to the semidormant, tissue cyst. The pathway for ABA production in T. gondii may be derived from a relict endosymbiont, acquired by ingestion of a red algal cell. Although the parasite has lost the capacity for photosynthesis, the plant-like nature of this signaling pathway may be exploited to develop new drugs. In support of this idea, an inhibitor of ABA biosynthesis protected mice against lethal infection with T. gondii. Here, we compare the role of ABA in parasites to its activities in plants, where it is know to control development and stress responses.

  20. Tolerization with BLP down-regulates HMGB1 a critical mediator of sepsis-related lethality.

    LENUS (Irish Health Repository)

    Coffey, J Calvin

    2012-02-03

    Tolerization with bacterial lipoprotein (BLP) affords a significant survival benefit in sepsis. Given that high mobility group box protein-1 (HMGB1) is a recognized mediator of sepsis-related lethality, we determined if tolerization with BLP leads to alterations in HMGB1. In vitro, BLP tolerization led to a reduction in HMGB1 gene transcription. This was mirrored at the protein level, as HMGB1 protein expression and release were reduced significantly in BLP-tolerized human THP-1 monocytic cells. BLP tolerance in vivo led to a highly significant, long-term survival benefit following challenge with lethal dose BLP in C57BL\\/6 mice. This was associated with an attenuation of HMGB1 release into the circulation, as evidenced by negligible serum HMGB1 levels in BLP-tolerized mice. Moreover, HMGB1 levels in peritoneal macrophages from BLP-tolerized mice were reduced significantly. Hence, tolerization with BLP leads to a down-regulation of HMGB1 protein synthesis and release. The improved survival associated with BLP tolerance could thus be explained by a reduction in HMGB1, were the latter associated with lethality in BLP-related sepsis. In testing this hypothesis, it was noted that neutralization of HMGB1, using anti-HMGB1 antibodies, abrogated BLP-associated lethality almost completely. To conclude, tolerization with BLP leads to a down-regulation of HMGB1, thus offering a novel means of targeting the latter. HMGB1 is also a mediator of lethality in BLP-related sepsis.

  1. The mechanism of ROS regulation of antibiotic resistance and antimicrobial lethality.

    Science.gov (United States)

    Lina, Ma; Hongfei, Mi; Yunxin, Xue; Dai, Wang; Xilin, Zhao

    2016-10-20

    Misuse and overuse of antibiotics have led to serious resistance problems that pose a grave threat to human health. How to solve the increasing antibiotic resistance problem is a huge challenge. Besides the traditional strategy of developing novel antimicrobial agents, exploring ways to enhance the lethal activity of antibiotics currently available is another feasible approach to fight against resistance. Recent studies showed that ROS plays an important role in regulating both antibiotic resistance and antimicrobial lethality. ROS produced by sublethal levels of antibiotic induces antibiotic resistance through activating drug efflux pumps via MarR(Multiple antibiotic resistance repressor)-MarA(Multiple antibiotic resistance activator), triggers the protective function against stress via SoxR (Superoxide response transcriptional regulator)-SoxS (Superoxide response transcription factor), and promotes mutagenesis by induction of SOS system. On the contrary, ROS triggered by lethal levels of antibiotic promotes bacterial killing and suppresses resistance. In addition to the concentration of antibiotic, the role of ROS in mediating antimicrobial resistance and bacterial killing is also regulated by a series of genetic regulators (e.g. MazEF, Cpx, SoxR, MarRAB). Thus, how ROS contribute to antimicrobial resistance and bacterial killing is complex. In this review, we summarized the mechanism of ROS in regulating antibiotic resistance and antimicrobial lethality, which may provide references and guidance for finding new ways to enhance antimicrobial lethality of currently available antimicrobials and battling antibiotic resistance.

  2. Impacts of globalisation on foodborne parasites.

    Science.gov (United States)

    Robertson, Lucy J; Sprong, Hein; Ortega, Ynes R; van der Giessen, Joke W B; Fayer, Ron

    2014-01-01

    Globalisation is a manmade phenomenon encompassing the spread and movement of everything, animate and inanimate, material and intangible, around the planet. The intentions of globalisation may be worthy--but may also have unintended consequences. Pathogens may also be spread, enabling their establishment in new niches and exposing new human and animal populations to infection. The plethora of foodborne parasites that could be distributed by globalisation has only recently been acknowledged and will provide challenges for clinicians, veterinarians, diagnosticians, and everyone concerned with food safety. Globalisation may also provide the resources to overcome some of these challenges. It will facilitate sharing of methods and approaches, and establishment of systems and databases that enable control of parasites entering the global food chain.

  3. Internal parasites of reptiles.

    Science.gov (United States)

    Raś-Noryńska, Małgorzata; Sokół, Rajmund

    2015-01-01

    Nowadays a growing number of exotic reptiles are kept as pets. The aim of this study was to determine the species of parasites found in reptile patients of veterinary practices in Poland. Fecal samples obtained from 76 lizards, 15 turtles and 10 snakes were examined by flotation method and direct smear stained with Lugol's iodine. In 63 samples (62.4%) the presence of parasite eggs and oocysts was revealed. Oocysts of Isospora spp. (from 33% to 100% of the samples, depending on the reptilian species) and Oxyurids eggs (10% to 75%) were predominant. In addition, isolated Eimeria spp. oocysts and Giardia intestinalis cysts were found, as well as Strongylus spp. and Hymenolepis spp. eggs. Pet reptiles are often infected with parasites, some of which are potentially dangerous to humans. A routine parasitological examination should be done in such animals.

  4. Foodborne protozoan parasites.

    Science.gov (United States)

    Dawson, David

    2005-08-25

    This report addresses Cryptosporidium, Giardia, Cyclospora, and more briefly, Toxoplasma as the main parasitic protozoa of concern to food production worldwide. Other parasitic protozoa may be spread in food or water but are not considered as great a risk to food manufacture. The protozoan parasites Cryptosporidium, Giardia, and Cyclospora have proven potential to cause waterborne and foodborne disease. Toxoplasma gondii has been considered a risk in specific cases, but humans are not its primary host. Cryptosporidium and Giardia are widespread in the environment, particularly the aquatic environment, and major outbreaks of cryptosporidiosis and giardiasis have occurred as a result of contaminated drinking water. Large outbreaks of waterborne cyclosporiasis have not been identified. Cryptosporidium, Giardia, and Cyclospora have potential significance in the preparation and consumption of fresh produce and in catering practice, in which ready-to-eat foods may be served that have not received heat treatment. None of the three organisms Cryptosporidium, Giardia, and Cyclospora has been shown to be a problem for heat processed food or tap water that has undergone appropriate treatment at a water treatment works. All three are sensitive to standard pasteurisation techniques. Although humans are not a primary host for T. gondii, the potential exists for both waterborne and foodborne toxoplasmosis. Parasitic protozoa do not multiply in foods, but they may survive in or on moist foods for months in cool, damp environments. Their ecology makes control of these parasites difficult. For general control of parasitic protozoa in the food chain, the following steps are necessary: - Follow good hygienic practice in food service and catering industries.- Minimise dissemination of cysts and oocysts in the farming environment and via human waste management.- Include these microorganisms in Hazard Analysis Critical Control Point (HACCP) plans of water suppliers, industries or sectors

  5. Siganus oramin recombinant L-amino acid oxidase is lethal to Cryptocaryon irritans.

    Science.gov (United States)

    Li, Ruijun; Dan, Xueming; Li, Anxing

    2013-12-01

    A novel antimicrobial and antiparasitic protein (APP/SR-LAAO) isolated from serum of the rabbitfish (Siganus oramin) was confirmed to be lethal to Cryptocaryon irritans, an important marine parasitic ciliate that causes marine white spot disease in a variety of wild and cultured fish. In this study, a recombinant SR-LAAO (rSR-LAAO) was expressed on a large scale in Escherichia coli Rosetta-gami™(DE3)pLysS cells. rSR-LAAO was expressed as an inactive form in the inclusion bodies. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that after purification, refolding and ultrafiltration, rSR-LAAO had a significantly cytotoxic effect on C. irritans theronts. Using light microscopy, scanning electron microscopy and fluorescence microscopy, we found that theronts rapidly became weakly motile, cilia became detached, cells became rounded, membranes eventually lysed in different cell positions and cytoplasmic contents leaked out of the cell. These results suggested the recombinant SR-LAAO was significantly lethal to C. irritans and the death process of the parasite incubated with rSR-LAAO was remarkably similar compared to the SR-LAAO group as reported earlier.

  6. Mining of lethal recessive genetic variation in Danish cattle

    DEFF Research Database (Denmark)

    Das, Ashutosh

    2015-01-01

    in fertility. The primary objective of this PhD projekt was to identify recessive lethal gentic variants in the main Danish dairy cattle breed. Holstein-Friesian utilzing next generation sequencing (NGS) data. This study shows a potential for the use of the NGS-based reverse genetic approach in identifying...... lethal or semi-lethal recessive gentic variation...

  7. Lethal midline granuloma syndrome: a diagnostic dilemma

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Bruno Niemeyer de Freitas; Bahia, Paulo Roberto Valle [Radiology, Hospital Universitario Clementino Fraga Filho - Universidade Federal do Rio de Janeiro (HUCFF-UFRJ), Rio de Janeiro, RJ (Brazil); Oliveira, Ana Luiza Vianna Sobral de Magalhaes [Resident of Medical Practice, Hospital Federal da Lagoa, Rio de Janeiro, RJ (Brazil); Marchon Junior, Joao Luiz [Unit of Computed Tomography, Hospital Federal da Lagoa, Rio de Janeiro, RJ (Brazil)

    2012-11-15

    The rare lethal midline granuloma syndrome is difficult to diagnose because of the wide array of related diseases and lack of knowledge by the majority of physicians. In the present report, the authors describe the case of a patient with this disease, caused by squamous cell carcinoma, drawing attention to differential diagnoses and to clinical and radiological findings that may be useful to define the diagnosis. (author)

  8. Brine shrimp lethality assay of Bacopa monnieri.

    Science.gov (United States)

    D'Souza, Prashanth; Deepak, Mundkinajeddu; Rani, Padmaja; Kadamboor, Sandhya; Mathew, Anjana; Chandrashekar, Arun P; Agarwal, Amit

    2002-03-01

    Successive petroleum ether, chloroform, ethanol and water extracts, a saponin rich fraction (SRF) and bacoside A isolated from Bacopa monnieri were tested for brine shrimp lethality. Successive ethanol extracts and SRF showed potent activity. Bacoside A showed the maximum activity with a LC(50) of 38.3 microg/mL. The results confirmed the previous reports of an anticancer effect of Bacopa monnieri and suggest bacoside A as the active constituent.

  9. Lethal Interpersonal Violence in the Middle Pleistocene

    OpenAIRE

    Nohemi Sala; Juan Luis Arsuaga; Ana Pantoja-Pérez; Adrián Pablos; Ignacio Martínez; Quam, Rolf M.; Asier Gómez-Olivencia; José María Bermúdez de Castro; Eudald Carbonell

    2015-01-01

    Evidence of interpersonal violence has been documented previously in Pleistocene members of the genus Homo, but only very rarely has this been posited as the possible manner of death. Here we report the earliest evidence of lethal interpersonal violence in the hominin fossil record. Cranium 17 recovered from the Sima de los Huesos Middle Pleistocene site shows two clear perimortem depression fractures on the frontal bone, interpreted as being produced by two episodes of localized blunt force ...

  10. Lethality in Desbuquois dysplasia: three new cases

    Energy Technology Data Exchange (ETDEWEB)

    Hall, B.D. [Department of Pediatrics, University of Kentucky College of Medicine, Lexington (United States)

    2001-01-01

    Three new cases of Desbuquois syndrome in two brothers and a sporadic male, all of whom died in early infancy, are presented to emphasize the high rate (33 %) of lethality in this variable, but serious skeletal dysplasia. Including the three presented patients and 10 of the 36 cases in the literature who died, most did so between birth and 7 months and from respiratory-related problems. Neonatal and infancy survivors should be monitored closely, particularly relative to their pulmonary status. (orig.)

  11. Complement component 5 promotes lethal thrombosis

    Science.gov (United States)

    Mizuno, Tomohiro; Yoshioka, Kengo; Mizuno, Masashi; Shimizu, Mie; Nagano, Fumihiko; Okuda, Tomoyuki; Tsuboi, Naotake; Maruyama, Shoichi; Nagamatsu, Tadashi; Imai, Masaki

    2017-01-01

    Extracellular histones promote platelet aggregation and thrombosis; this is followed by induction of coagulation disorder, which results in exhaustion of coagulation factors. Complement component 5 (C5) is known to be associated with platelet aggregation and coagulation system activation. To date, the pathological mechanism underlying liver injury has remained unclear. Here, we investigated whether C5 promotes liver injury associated with histone-induced lethal thrombosis. C5-sufficient and C5-deficient mice received single tail vein injections of purified, unfractionated histones obtained from calf thymus (45–75 μg/g). Subsequently, the mice were monitored for survival for up to 72 h. Based on the survival data, the 45 μg/g dose was used for analysis of blood cell count, liver function, blood coagulation ability, and promotion of platelet aggregation and platelet/leukocyte aggregate (PLA) production by extracellular histones. C5-deficient mice were protected from lethal thrombosis and had milder thrombocytopenia, consumptive coagulopathy, and liver injury with embolism and lower PLA production than C5-sufficient mice. These results indicate that C5 is associated with coagulation disorders, PLA production, and embolism-induced liver injury. In conclusion, C5 promotes liver injury associated with histone-induced lethal thrombosis. PMID:28205538

  12. Lethal interpersonal violence in the Middle Pleistocene.

    Science.gov (United States)

    Sala, Nohemi; Arsuaga, Juan Luis; Pantoja-Pérez, Ana; Pablos, Adrián; Martínez, Ignacio; Quam, Rolf M; Gómez-Olivencia, Asier; Bermúdez de Castro, José María; Carbonell, Eudald

    2015-01-01

    Evidence of interpersonal violence has been documented previously in Pleistocene members of the genus Homo, but only very rarely has this been posited as the possible manner of death. Here we report the earliest evidence of lethal interpersonal violence in the hominin fossil record. Cranium 17 recovered from the Sima de los Huesos Middle Pleistocene site shows two clear perimortem depression fractures on the frontal bone, interpreted as being produced by two episodes of localized blunt force trauma. The type of injuries, their location, the strong similarity of the fractures in shape and size, and the different orientations and implied trajectories of the two fractures suggest they were produced with the same object in face-to-face interpersonal conflict. Given that either of the two traumatic events was likely lethal, the presence of multiple blows implies an intention to kill. This finding shows that the lethal interpersonal violence is an ancient human behavior and has important implications for the accumulation of bodies at the site, supporting an anthropic origin.

  13. Lethal interpersonal violence in the Middle Pleistocene.

    Directory of Open Access Journals (Sweden)

    Nohemi Sala

    Full Text Available Evidence of interpersonal violence has been documented previously in Pleistocene members of the genus Homo, but only very rarely has this been posited as the possible manner of death. Here we report the earliest evidence of lethal interpersonal violence in the hominin fossil record. Cranium 17 recovered from the Sima de los Huesos Middle Pleistocene site shows two clear perimortem depression fractures on the frontal bone, interpreted as being produced by two episodes of localized blunt force trauma. The type of injuries, their location, the strong similarity of the fractures in shape and size, and the different orientations and implied trajectories of the two fractures suggest they were produced with the same object in face-to-face interpersonal conflict. Given that either of the two traumatic events was likely lethal, the presence of multiple blows implies an intention to kill. This finding shows that the lethal interpersonal violence is an ancient human behavior and has important implications for the accumulation of bodies at the site, supporting an anthropic origin.

  14. Leishmaniasis–HIV coinfection: current challenges

    Science.gov (United States)

    Lindoso, José Angelo Lauletta; Cunha, Mirella Alves; Queiroz, Igor Thiago; Moreira, Carlos Henrique Valente

    2016-01-01

    Leishmaniasis – human immunodeficiency virus (HIV) coinfection can manifest itself as tegumentary or visceral leishmaniasis. Almost 35 countries have reported autochthonous coinfections. Visceral leishmaniasis is more frequently described. However, usual and unusual manifestations of tegumentary leishmaniasis have been reported mainly in the Americas, but the real prevalence of Leishmania infection in HIV-infected patients is not clear. Regarding the clinical manifestations, there are some reports showing unusual manifestations in visceral leishmaniasis and tegumentary leishmaniasis in HIV-infected patients; yet, the usual manifestations are more frequent. Leishmaniasis diagnosis relies on clinical methods, but serological tests are used to diagnose visceral leishmaniasis despite them having a low sensitivity to tegumentary leishmaniasis. The search for the parasite is used to diagnose both visceral leishmaniasis and tegumentary leishmaniasis. Nevertheless, in HIV-infected patients, the sensitivity of serology is very low. Drugs available to treat leishmaniasis are more restricted and cause severe side effects. Furthermore, in HIV-infected patients, these side effects are more prominent and relapses and lethality are more recurrent. In this article, we discuss the current challenges of tegumentary leishmaniasis and visceral leishmaniasis–HIV infection, focusing mainly on the clinical manifestations, diagnosis, and treatment of leishmaniasis. PMID:27785103

  15. The impact of genomics on population genetics of parasitic diseases.

    Science.gov (United States)

    Hupalo, Daniel N; Bradic, Martina; Carlton, Jane M

    2015-02-01

    Parasites, defined as eukaryotic microbes and parasitic worms that cause global diseases of human and veterinary importance, span many lineages in the eukaryotic Tree of Life. Historically challenging to study due to their complicated life-cycles and association with impoverished settings, their inherent complexities are now being elucidated by genome sequencing. Over the course of the last decade, projects in large sequencing centers, and increasingly frequently in individual research labs, have sequenced dozens of parasite reference genomes and field isolates from patient populations. This 'tsunami' of genomic data is answering questions about parasite genetic diversity, signatures of evolution orchestrated through anti-parasitic drug and host immune pressure, and the characteristics of populations. This brief review focuses on the state of the art of parasitic protist genomics, how the peculiar genomes of parasites are driving creative methods for their sequencing, and the impact that next-generation sequencing is having on our understanding of parasite population genomics and control of the diseases they cause.

  16. Cardiac-specific catalase overexpression rescues anthrax lethal toxin-induced cardiac contractile dysfunction: role of oxidative stress and autophagy

    Directory of Open Access Journals (Sweden)

    Kandadi Machender R

    2012-11-01

    Full Text Available Abstract Background Lethal and edema toxins secreted by Bacillus anthracis during anthrax infection were found to incite serious cardiovascular complications. However, the underlying mechanisms in anthrax lethal toxin-induced cardiac anomalies remain unknown. This study was designed to evaluate the impact of antioxidant enzyme catalase in anthrax lethal toxin-induced cardiomyocyte contractile dysfunction. Methods Wild type (WT and cardiac-specific catalase overexpression mice were challenged with lethal toxin (2 μg/g, intraperotineally (i.p.. Cardiomyocyte contractile and intracellular Ca2+ properties were assessed 18 h later using an IonOptix edge-detection system. Proteasome function was assessed using chymotrypsin-like and caspase-like activities. GFP-LC3 puncta and Western blot analysis were used to evaluate autophagy and protein ubiquitination. Results Lethal toxin exposure suppressed cardiomyocyte contractile function (suppressed peak shortening, maximal velocity of shortening/re-lengthening, prolonged duration of shortening/re-lengthening, and impaired intracellular Ca2+ handling, the effects of which were alleviated by catalase. In addition, lethal toxin triggered autophagy, mitochondrial and ubiquitin-proteasome defects, the effects of which were mitigated by catalase. Pretreatment of cardiomyocytes from catalase mice with the autophagy inducer rapamycin significantly attenuated or ablated catalase-offered protection against lethal toxin-induced cardiomyocyte dysfunction. On the other hand, the autophagy inhibitor 3-MA ablated or significantly attenuated lethal toxin-induced cardiomyocyte contractile anomalies. Conclusions Our results suggest that catalase is protective against anthrax lethal toxin-induced cardiomyocyte contractile and intracellular Ca2+ anomalies, possibly through regulation of autophagy and mitochondrial function.

  17. On biomass of parasitic plants

    Energy Technology Data Exchange (ETDEWEB)

    He, J H [Modern Textile Institute, Donghua University, 1882 Yan' an Xilu Road, Shanghai 200051 (China); Mo, L-F [School of Information Engineering, Zhejiang Forestry College, Lin' an 311300, Zhejiang (China)], E-mail: jhhe@dhu.edu.cn

    2008-02-15

    An extremely simple and elementary but rigorous derivation of maximal biomass of parasitic plants is given using an assumption that metabolic rate of the parasite should not be larger than that of its host organ.

  18. On biomass of parasitic plants

    Science.gov (United States)

    He, J. H.; Mo, L.-F.

    2008-02-01

    An extremely simple and elementary but rigorous derivation of maximal biomass of parasitic plants is given using an assumption that metabolic rate of the parasite should not be larger than that of its host organ

  19. Enteric parasites and AIDS

    Directory of Open Access Journals (Sweden)

    Sérgio Cimerman

    1999-11-01

    Full Text Available OBJECTIVE: To report on the importance of intestinal parasites in patients with AIDS, showing relevant data in the medical literature, with special emphasis on epidemiology, diagnosis and treatment of enteroparasitosis, especially cryptosporidiasis, isosporiasis, microsporidiasis and strongyloidiasis. DESIGN: Narrative review.

  20. Parasites and the skin

    African Journals Online (AJOL)

    2009-06-11

    Jun 11, 2009 ... remind you of those rare and wonderful infestations that you might never see. ... from a burrow, mounted on a glass slide. The findings are ... Parasitic infections may be confined to the skin or may have skin involvement as part ...

  1. Parasites and Foodborne Illness

    Science.gov (United States)

    ... called "Crypto", is a one-celled, microscopic shelled parasite and a significant cause of waterborne and foodborne illness worldwide. It is found in the intestines of many herd animals including cows, sheep, goats, deer, and elk. The illness could be intestinal, ...

  2. Ungulate malaria parasites

    Science.gov (United States)

    Templeton, Thomas J.; Asada, Masahito; Jiratanh, Montakan; Ishikawa, Sohta A.; Tiawsirisup, Sonthaya; Sivakumar, Thillaiampalam; Namangala, Boniface; Takeda, Mika; Mohkaew, Kingdao; Ngamjituea, Supawan; Inoue, Noboru; Sugimoto, Chihiro; Inagaki, Yuji; Suzuki, Yasuhiko; Yokoyama, Naoaki; Kaewthamasorn, Morakot; Kaneko, Osamu

    2016-01-01

    Haemosporida parasites of even-toed ungulates are diverse and globally distributed, but since their discovery in 1913 their characterization has relied exclusively on microscopy-based descriptions. In order to bring molecular approaches to bear on the identity and evolutionary relationships of ungulate malaria parasites, we conducted Plasmodium cytb-specific nested PCR surveys using blood from water buffalo in Vietnam and Thailand, and goats in Zambia. We found that Plasmodium is readily detectable from water buffalo in these countries, indicating that buffalo Plasmodium is distributed in a wider region than India, which is the only area in which buffalo Plasmodium has been reported. Two types (I and II) of Plasmodium sequences were identified from water buffalo and a third type (III) was isolated from goat. Morphology of the parasite was confirmed in Giemsa-reagent stained blood smears for the Type I sample. Complete mitochondrial DNA sequences were isolated and used to infer a phylogeny in which ungulate malaria parasites form a monophyletic clade within the Haemosporida, and branch prior to the clade containing bird, lizard and other mammalian Plasmodium. Thus it is likely that host switching of Plasmodium from birds to mammals occurred multiple times, with a switch to ungulates independently from other mammalian Plasmodium. PMID:26996979

  3. Parasitic Diseases With Cutaneous Manifestations.

    Science.gov (United States)

    Ash, Mark M; Phillips, Charles M

    2016-01-01

    Parasitic diseases result in a significant global health burden. While often thought to be isolated to returning travelers, parasitic diseases can also be acquired locally in the United States. Therefore, clinicians must be aware of the cutaneous manifestations of parasitic diseases to allow for prompt recognition, effective management, and subsequent mitigation of complications. This commentary also reviews pharmacologic treatment options for several common diseases.

  4. microRNAs in parasites and parasite infection.

    Science.gov (United States)

    Zheng, Yadong; Cai, Xuepeng; Bradley, Janette E

    2013-03-01

    miRNAs, a subclass of small regulatory RNAs, are present from ancient unicellular protozoans to parasitic helminths and parasitic arthropods. The miRNA-silencing mechanism appears, however, to be absent in a number of protozoan parasites. Protozoan miRNAs and components of their silencing machinery possess features different from other eukaryotes, providing some clues on the evolution of the RNA-induced silencing machinery. miRNA functions possibly associate with neoblast biology, development, physiology, infection and immunity of parasites. Parasite infection can alter host miRNA expression that can favor both parasite clearance and infection. miRNA pathways are, thus, a potential target for the therapeutic control of parasitic diseases.

  5. Counter-regulatory anti-parasite cytokine responses during concurrent Plasmodium yoelii and intestinal helminth infections in mice

    Science.gov (United States)

    Malaria and helminth infections are two of the most prevalent parasitic diseases in tropical areas. While concomitant infection is common, mechanisms contributing to altered disease outcomes during co-infection remain poorly defined. We have previously reported exacerbation of normally non-lethal ...

  6. Mutation induced extinction in finite populations: lethal mutagenesis and lethal isolation.

    Directory of Open Access Journals (Sweden)

    C Scott Wylie

    Full Text Available Reproduction is inherently risky, in part because genomic replication can introduce new mutations that are usually deleterious toward fitness. This risk is especially severe for organisms whose genomes replicate "semi-conservatively," e.g. viruses and bacteria, where no master copy of the genome is preserved. Lethal mutagenesis refers to extinction of populations due to an unbearably high mutation rate (U, and is important both theoretically and clinically, where drugs can extinguish pathogens by increasing their mutation rate. Previous theoretical models of lethal mutagenesis assume infinite population size (N. However, in addition to high U, small N can accelerate extinction by strengthening genetic drift and relaxing selection. Here, we examine how the time until extinction depends jointly on N and U. We first analytically compute the mean time until extinction (τ in a simplistic model where all mutations are either lethal or neutral. The solution motivates the definition of two distinct regimes: a survival phase and an extinction phase, which differ dramatically in both how τ scales with N and in the coefficient of variation in time until extinction. Next, we perform stochastic population-genetics simulations on a realistic fitness landscape that both (i features an epistatic distribution of fitness effects that agrees with experimental data on viruses and (ii is based on the biophysics of protein folding. More specifically, we assume that mutations inflict fitness penalties proportional to the extent that they unfold proteins. We find that decreasing N can cause phase transition-like behavior from survival to extinction, which motivates the concept of "lethal isolation." Furthermore, we find that lethal mutagenesis and lethal isolation interact synergistically, which may have clinical implications for treating infections. Broadly, we conclude that stably folded proteins are only possible in ecological settings that support sufficiently

  7. 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.

  8. Metazoan Parasites of Antarctic Fishes.

    Science.gov (United States)

    Oğuz, Mehmet Cemal; Tepe, Yahya; Belk, Mark C; Heckmann, Richard A; Aslan, Burçak; Gürgen, Meryem; Bray, Rodney A; Akgül, Ülker

    2015-06-01

    To date, there have been nearly 100 papers published on metazoan parasites of Antarctic fishes, but there has not yet been any compilation of a species list of fish parasites for this large geographic area. Herein, we provide a list of all documented occurrences of monogenean, cestode, digenean, acanthocephalan, nematode, and hirudinean parasites of Antarctic fishes. The list includes nearly 250 parasite species found in 142 species of host fishes. It is likely that there are more species of fish parasites, which are yet to be documented from Antarctic waters.

  9. Impact of the Timing of Morphine Administration on Lipopolysaccharide-Mediated Lethal Endotoxic Shock in Mice.

    Science.gov (United States)

    Fukada, Tomoko; Kato, Hidehito; Ozaki, Makoto; Yagi, Junji

    2016-05-01

    Sepsis is a serious condition related to systemic inflammation, organ dysfunction, and organ failure. It is a subset of the cytokine storm caused by dysregulation of cytokine production. Morphine influences the severity of infection in vivo and in vitro because it regulates cytokine production. We investigated the immunological function of morphine using a mouse model of septic shock. We treated mice with α-galactosylceramide (2 μg/mouse) to induce lethal endotoxic shock following a challenge with lipopolysaccharide (LPS, 1.5 μg/mouse). This model represents acute lung injury and respiratory failure, and reflects the clinical features of severe septic shock. We evaluated the effect of the timing of morphine (0.8 mg/mouse) administration on the survival rate, cytokine production in vivo, and histological changes of mice with LPS-mediated lethal endotoxic shock. Morphine treatment before LPS challenge suppressed lethal endotoxic shock. In contrast, when we administered after LPS, morphine exacerbated lethal endotoxic shock; hematoxylin and eosin staining revealed a marked increase in the accumulation of infiltrates comprising polymorphonuclear leukocytes and mononuclear cells in the lung; and Elastica van Gieson staining revealed the destruction of alveoli. The plasma levels of tumor necrosis factor-α, interferon-γ, monocyte-chemotactic protein-1, and interleukin-12 in the group treated with morphine after LPS challenge were higher than those treated with morphine before LPS challenge. In conclusion, one of the factors that determine whether morphine exacerbates or inhibits infection is the timing of its administration. Morphine treatment before shock improved the survival rate, and morphine treatment after shock decreased the rate of survival.

  10. INTESTINAL PARASITES IN IRAN

    Directory of Open Access Journals (Sweden)

    K. Mohammad

    1995-12-01

    Full Text Available The purpose of this study was to investigate the status and epidemiology of Intestinal Parasites in Iran. The information was driven from an extensive Health Survey which was done by the Ministry of Health and Medical Education, deputy of Research Affairs in 1990-92. Sampling fraction was 1 per 1000 of individuals aged between 2 and 69, the sampling method was cluster sampling and each cluster consisted of 7 families. Formal-ether was the method of finding parasites which included: Oxior, Ascariasis, Giardiasis, Entamoeba-histolytica, Tinea, Strongyloidiasis, Ancylostoma, and Trichocephaliasis. The highest prevalence rate belonged to Giardiasis with 14.4% and the lowest one belonged to Tinea and Ancylostoma with 0.2%. The prevalence rate in rural area was significantly lower than urban area (p<0.0001.

  11. IFNAR1-Signalling Obstructs ICOS-mediated Humoral Immunity during Non-lethal Blood-Stage Plasmodium Infection

    Science.gov (United States)

    Sebina, Ismail; James, Kylie R.; Soon, Megan S. F.; Best, Shannon E.; Montes de Oca, Marcela; Amante, Fiona H.; Thomas, Bryce S.; Beattie, Lynette; Souza-Fonseca-Guimaraes, Fernando; Smyth, Mark J.; Hertzog, Paul J.; Hill, Geoffrey R.; Engwerda, Christian R.

    2016-01-01

    Parasite-specific antibodies protect against blood-stage Plasmodium infection. However, in malaria-endemic regions, it takes many months for naturally-exposed individuals to develop robust humoral immunity. Explanations for this have focused on antigenic variation by Plasmodium, but have considered less whether host production of parasite-specific antibody is sub-optimal. In particular, it is unclear whether host immune factors might limit antibody responses. Here, we explored the effect of Type I Interferon signalling via IFNAR1 on CD4+ T-cell and B-cell responses in two non-lethal murine models of malaria, P. chabaudi chabaudi AS (PcAS) and P. yoelii 17XNL (Py17XNL) infection. Firstly, we demonstrated that CD4+ T-cells and ICOS-signalling were crucial for generating germinal centre (GC) B-cells, plasmablasts and parasite-specific antibodies, and likewise that T follicular helper (Tfh) cell responses relied on B cells. Next, we found that IFNAR1-signalling impeded the resolution of non-lethal blood-stage infection, which was associated with impaired production of parasite-specific IgM and several IgG sub-classes. Consistent with this, GC B-cell formation, Ig-class switching, plasmablast and Tfh differentiation were all impaired by IFNAR1-signalling. IFNAR1-signalling proceeded via conventional dendritic cells, and acted early by limiting activation, proliferation and ICOS expression by CD4+ T-cells, by restricting the localization of activated CD4+ T-cells adjacent to and within B-cell areas of the spleen, and by simultaneously suppressing Th1 and Tfh responses. Finally, IFNAR1-deficiency accelerated humoral immune responses and parasite control by boosting ICOS-signalling. Thus, we provide evidence of a host innate cytokine response that impedes the onset of humoral immunity during experimental malaria. PMID:27812214

  12. Bacillus anthracis lethal toxin reduces human alveolar epithelial barrier function.

    Science.gov (United States)

    Langer, Marybeth; Duggan, Elizabeth Stewart; Booth, John Leland; Patel, Vineet Indrajit; Zander, Ryan A; Silasi-Mansat, Robert; Ramani, Vijay; Veres, Tibor Zoltan; Prenzler, Frauke; Sewald, Katherina; Williams, Daniel M; Coggeshall, Kenneth Mark; Awasthi, Shanjana; Lupu, Florea; Burian, Dennis; Ballard, Jimmy Dale; Braun, Armin; Metcalf, Jordan Patrick

    2012-12-01

    The lung is the site of entry for Bacillus anthracis in inhalation anthrax, the deadliest form of the disease. Bacillus anthracis produces virulence toxins required for disease. Alveolar macrophages were considered the primary target of the Bacillus anthracis virulence factor lethal toxin because lethal toxin inhibits mouse macrophages through cleavage of MEK signaling pathway components, but we have reported that human alveolar macrophages are not a target of lethal toxin. Our current results suggest that, unlike human alveolar macrophages, the cells lining the respiratory units of the lung, alveolar epithelial cells, are a target of lethal toxin in humans. Alveolar epithelial cells expressed lethal toxin receptor protein, bound the protective antigen component of lethal toxin, and were subject to lethal-toxin-induced cleavage of multiple MEKs. These findings suggest that human alveolar epithelial cells are a target of Bacillus anthracis lethal toxin. Further, no reduction in alveolar epithelial cell viability was observed, but lethal toxin caused actin rearrangement and impaired desmosome formation, consistent with impaired barrier function as well as reduced surfactant production. Therefore, by compromising epithelial barrier function, lethal toxin may play a role in the pathogenesis of inhalation anthrax by facilitating the dissemination of Bacillus anthracis from the lung in early disease and promoting edema in late stages of the illness.

  13. Costimulatory Effects of an Immunodominant Parasite Antigen Paradoxically Prevent Induction of Optimal CD8 T Cell Protective Immunity.

    Directory of Open Access Journals (Sweden)

    Christopher S Eickhoff

    2016-09-01

    Full Text Available Trypanosoma cruzi infection is controlled but not eliminated by host immunity. The T. cruzi trans-sialidase (TS gene superfamily encodes immunodominant protective antigens, but expression of altered peptide ligands by different TS genes has been hypothesized to promote immunoevasion. We molecularly defined TS epitopes to determine their importance for protection versus parasite persistence. Peptide-pulsed dendritic cell vaccination experiments demonstrated that one pair of immunodominant CD4+ and CD8+ TS peptides alone can induce protective immunity (100% survival post-lethal parasite challenge. TS DNA vaccines have been shown by us (and others to protect BALB/c mice against T. cruzi challenge. We generated a new TS vaccine in which the immunodominant TS CD8+ epitope MHC anchoring positions were mutated, rendering the mutant TS vaccine incapable of inducing immunity to the immunodominant CD8 epitope. Immunization of mice with wild type (WT and mutant TS vaccines demonstrated that vaccines encoding enzymatically active protein and the immunodominant CD8+ T cell epitope enhance subdominant pathogen-specific CD8+ T cell responses. More specifically, CD8+ T cells from WT TS DNA vaccinated mice were responsive to 14 predicted CD8+ TS epitopes, while T cells from mutant TS DNA vaccinated mice were responsive to just one of these 14 predicted TS epitopes. Molecular and structural biology studies revealed that this novel costimulatory mechanism involves CD45 signaling triggered by enzymatically active TS. This enhancing effect on subdominant T cells negatively regulates protective immunity. Using peptide-pulsed DC vaccination experiments, we have shown that vaccines inducing both immunodominant and subdominant epitope responses were significantly less protective than vaccines inducing only immunodominant-specific responses. These results have important implications for T. cruzi vaccine development. Of broader significance, we demonstrate that increasing

  14. Recombinant raccoon pox vaccine protects mice against lethal plague

    Science.gov (United States)

    Osorio, J.E.; Powell, T.D.; Frank, R.S.; Moss, K.; Haanes, E.J.; Smith, S.R.; Rocke, T.E.; Stinchcomb, D.T.

    2003-01-01

    Using a raccoon poxvirus (RCN) expression system, we have developed new recombinant vaccines that can protect mice against lethal plague infection. We tested the effects of a translation enhancer (EMCV-IRES) in combination with a secretory (tPA) signal or secretory (tPA) and membrane anchoring (CHV-gG) signals on in vitro antigen expression of F1 antigen in tissue culture and the induction of antibody responses and protection against Yersinia pestis challenge in mice. The RCN vector successfully expressed the F1 protein of Y. pestis in vitro. In addition, the level of expression was increased by the insertion of the EMCV-IRES and combinations of this and the secretory signal or secretory and anchoring signals. These recombinant viruses generated protective immune responses that resulted in survival of 80% of vaccinated mice upon challenge with Y. pestis. Of the RCN-based vaccines we tested, the RCN-IRES-tPA-YpF1 recombinant construct was the most efficacious. Mice vaccinated with this construct withstood challenge with as many as 1.5 million colony forming units of Y. pestis (7.7??104LD50). Interestingly, vaccination with F1 fused to the anchoring signal (RCN-IRES-tPA-YpF1-gG) elicited significant anti-F1 antibody titers, but failed to protect mice from plague challenge. Our studies demonstrate, in vitro and in vivo, the potential importance of the EMCV-IRES and secretory signals in vaccine design. These molecular tools provide a new approach for improving the efficacy of vaccines. In addition, these novel recombinant vaccines could have human, veterinary, and wildlife applications in the prevention of plague. ?? 2002 Elsevier Science Ltd. All rights reserved.

  15. Suicide Intent and Accurate Expectations of Lethality: Predictors of Medical Lethality of Suicide Attempts

    Science.gov (United States)

    Brown, Gregory K.; Henriques, Gregg R.; Sosdjan, Daniella; Beck, Aaron T.

    2004-01-01

    The degree of intent to commit suicide and the severity of self-injury were examined in individuals (N = 180) who had recently attempted suicide. Although a minimal association was found between the degree of suicide intent and the degree of lethality of the attempt, the accuracy of expectations about the likelihood of dying was found to moderate…

  16. Parasitic zoonoses; public health and veterinary perspectives.

    Science.gov (United States)

    Graczyk, Tadeusz K; Tamang, Leena; Doocy, Shannon C

    2005-01-01

    The importance of parasitic zoonoses continues to increase on both local and global scales as interactions between people and animals become more frequent through global travel, intensification of agriculture, habitat devastation, and changes in world trade patterns. A current and real threat is the potential for a deliberate introduction of a zoonotic disease through the prospect of bioterrorism. Parasitic zoonoses represent significant problems in public health, animal agriculture and conservation, and the meat industry. There is an urgent need for integration of medical and veterinary services, continuous disease surveillance in both humans and animals, the teaching of zoonoses to medical doctors, and intensified research on zoonotic agents and diseases. The convergence of both public health and veterinary services currently represents a real challenge for managing zoonotic diseases.

  17. Evaluation of parasitic consumption for a CSP plant

    Science.gov (United States)

    Ramorakane, Relebohile John; Dinter, Frank

    2016-05-01

    With the continuous development and desire to build alternative effective and efficient power plants, Concentrated Solar Power (CSP) plants (and more specifically the Parabolic Trough CSP Plants) have proven to be one of the alternative energy resources for the future. On this regard more emphasis and research is being employed to better this power plant technology, where one of the main challenges to these plants is to improve their efficiency by optimizing the parasitic load, wherein one of the major causes of the power plants' reduced overall efficiency arises from their parasitic load consumption. This project is therefore aimed at evaluating the parasitic load on Andasol 3 Power Plant, which is a 50 MW Parabolic Trough Power Plant with a 7.5 hours of full load storage system. It was hence determined that the total power plant's parasitic load consumption is about 12% in summer season and between 16% and 24% in winter season. In an effort to improve the power plant's efficiency, a couple of measures to reduce the parasitic load consumption were recommended, and also an alternative and cheaper source of parasitic load feeding plant, during the day (when the parasitic load consumption is highest) was proposed/recommended.

  18. [Status and future focus of the national control program on parasitic diseases].

    Science.gov (United States)

    Xiao-Nong, Zhou

    2011-10-01

    The achievements and challenges in the national control program on parasitic diseases in PR China were presented after trend analysis of the national and international control activities and programs. The future focus on research and control of parasitic diseases in PR China was put forward in order to achieve the long-term goal of eliminating the parasitic diseases as public health problem in the country.

  19. DNA vaccines: a rational design against parasitic diseases.

    Science.gov (United States)

    Carvalho, Joana A; Rodgers, Jean; Atouguia, Jorge; Prazeres, Duarte M F; Monteiro, Gabriel A

    2010-02-01

    Parasitic diseases are one of the most devastating causes of morbidity and mortality worldwide. Although immunization against these infections would be an ideal solution, the development of effective vaccines has been hampered by specific challenges posed by parasitic pathogens. Plasmid-based DNA vaccines may prove to be promising immunization tools in this area because vectors can be designed to integrate several antigens from different stages of the parasite life cycle or different subspecies; vaccines, formulations and immunization protocols can be tuned to match the immune response that offers protective immunity; and DNA vaccination is an affordable platform for developing countries. Partial and full protective immunity have been reported following DNA vaccination against the most significant parasitic diseases in the world.

  20. Nutrition and parasite interaction.

    Science.gov (United States)

    Coop, R L; Holmes, P H

    1996-01-01

    This overview focuses on the interaction between nutritional status and gastrointestinal nematode infection in ruminants and considers: (i) the influence of the parasite on host metabolism; and (ii) the effect of host nutrition on the establishment and survival of parasite populations, the development of the host-immune response and the pathophysiology of infection. Gastrointestinal nematodes reduce voluntary feed intake and efficiency of feed utilisation, a key feature being an increased endogenous loss of protein into the gastrointestinal tract. Overall there is movement of protein from productive processes into repair of the gastrointestinal tract, synthesis of plasma proteins and mucoprotein production. Although reduction in feed intake is a major factor contributing to the reduced performance of parasitised ruminants, the underlying mechanisms of the anorexia are poorly understood. Supplementation of the diet with additional protein does not appear to affect initial establishment of nematode infections but the pathophysiological consequences are generally more severe on lower planes of protein nutrition. The main effect of protein supplementation is to increase the rate of acquisition of immunity and increase resistance to reinfection and this has been associated with an enhanced cellular immune response in the gastrointestinal mucosa. The unresponsiveness of the young lamb can be improved by dietary protein supplementation. Recent trials have shown that growing sheep offered a free choice between a low and a high protein ration are able to modify their diet selection in order to alleviate the increase in protein requirements which result from gastrointestinal nematode infection. Studies on the influence of nutrition on the expression of genotype have shown that the benefits of a superior genotype are not lost on a low protein diet whereas a high protein diet can partially emeliorate the disadvantages of an inferior genotype. In addition to dietary protein

  1. [Emerging parasitic diseases].

    Science.gov (United States)

    Weibel Galluzzo, C; Wagner, N; Michel, Y; Jackson, Y; Chappuis, F

    2014-05-07

    Travels, migration and circulation of goods facilitate the emergence of new infectious diseases often unrecognized outside endemic areas. Most of emerging infections are of viral origin. Muscular Sarcocystis infection, an acute illness acquired during short trips to Malaysia, and Chagas disease, a chronic illness with long incubation period found among Latin American migrants, are two very different examples of emerging parasitic diseases. The former requires a preventive approach for travelers going to Malaysia and must be brought forth when they return with fever, myalgia and eosinophilia, while the latter requires a proactive attitude to screen Latin American migrant populations that may face difficulties in accessing care.

  2. Alleged lethal sorcery in East Timor.

    Science.gov (United States)

    Pollanen, Michael S

    2004-01-01

    A wide range of cultural and social perspectives exists on the concept of sudden and unexpected death. In countries, without a formal system of death investigation, sudden death is shrouded in mysticism often based on traditional belief systems. This cultural perspective on sudden death is often at variance with medical and forensic concepts and may include explanations such as sorcery, magic, and voodoo. In this case report, the postmortem findings in an alleged victim of lethal 'black magic', known as ema halo by the indigenous people of East Timor, is described. The alleged victim died suddenly in front of witnesses. At autopsy, marked dilation of a bicuspid aortic valve with annuloaortic ectasia and a sinus of Valsalva aneurysm was found after exhumation of the body. The findings mitigated the local belief in witchcraft and established a natural manner of death.

  3. Lethal photosensitization of biofilm-grown bacteria

    Science.gov (United States)

    Wilson, Michael

    1997-12-01

    Antibacterial agents are increasingly being used for the prophylaxis and treatment of oral diseases. As these agents can be rendered ineffective by resistance development in the target organisms there is a need to develop alternative antimicrobial approaches. Light-activated antimicrobial agents release singlet oxygen and free radicals which can kill adjacent bacteria and a wide range of cariogenic and periodontopathogenic bacteria has been shown to be susceptible to such agents. In the oral cavity these organisms are present as biofilms (dental plaques) which are less susceptible to traditional antimicrobial agents than bacterial suspensions. The results of these studies have shown that biofilm-grown oral bacteria are also susceptible to lethal photosensitization although the light energy doses required are grater than those needed to kill the organisms when they are grown as aqueous suspensions.

  4. Drug facilitated sexual assault with lethal outcome

    DEFF Research Database (Denmark)

    Mehling, Lena-Maria; Johansen, Sys Stybe; Wang, Xin

    2016-01-01

    A very serious case of DFSA (drug facilitated sexual assault) is presented, in which a six-year-old girl died following sedation with γ-hydroxybutyric acid (GHB). She had been sexually abused by a relative. Samples of cardiac blood, bile, vitreous humour, liver, kidney, brain tissues and hair were...... segments of hair - up to 12 cm distant from the hair scalp - GHB concentrations were higher than the overall found endogenous range of 2-3 ng/mg. Police investigations revealed that the uncle had also administered GHB to the older half-sister. Therefore, a sample of her hair was analysed accordingly......, but unremarkable results were obtained. Comparing our toxicological results with police investigations and the offender's statements it can be assumed that the 6-year-old girl had ingested GHB. By exclusion of other causes of death a lethal intoxication with GHB could be confirmed....

  5. Modelling parasite transmission in a grazing system: the importance of host behaviour and immunity.

    Directory of Open Access Journals (Sweden)

    Naomi J Fox

    Full Text Available Parasitic helminths present one of the most pervasive challenges to grazing herbivores. Many macro-parasite transmission models focus on host physiological defence strategies, omitting more complex interactions between hosts and their environments. This work represents the first model that integrates both the behavioural and physiological elements of gastro-intestinal nematode transmission dynamics in a managed grazing system. A spatially explicit, individual-based, stochastic model is developed, that incorporates both the hosts' immunological responses to parasitism, and key grazing behaviours including faecal avoidance. The results demonstrate that grazing behaviour affects both the timing and intensity of parasite outbreaks, through generating spatial heterogeneity in parasite risk and nutritional resources, and changing the timing of exposure to the parasites' free-living stages. The influence of grazing behaviour varies with the host-parasite combination, dependent on the development times of different parasite species and variations in host immune response. Our outputs include the counterintuitive finding that under certain conditions perceived parasite avoidance behaviours (faecal avoidance can increase parasite risk, for certain host-parasite combinations. Through incorporating the two-way interaction between infection dynamics and grazing behaviour, the potential benefits of parasite-induced anorexia are also demonstrated. Hosts with phenotypic plasticity in grazing behaviour, that make grazing decisions dependent on current parasite burden, can reduce infection with minimal loss of intake over the grazing season. This paper explores how both host behaviours and immunity influence macro-parasite transmission in a spatially and temporally heterogeneous environment. The magnitude and timing of parasite outbreaks is influenced by host immunity and behaviour, and the interactions between them; the incorporation of both regulatory processes

  6. Unexpected hosts: imaging parasitic diseases.

    Science.gov (United States)

    Rodríguez Carnero, Pablo; Hernández Mateo, Paula; Martín-Garre, Susana; García Pérez, Ángela; Del Campo, Lourdes

    2017-02-01

    Radiologists seldom encounter parasitic diseases in their daily practice in most of Europe, although the incidence of these diseases is increasing due to migration and tourism from/to endemic areas. Moreover, some parasitic diseases are still endemic in certain European regions, and immunocompromised individuals also pose a higher risk of developing these conditions. This article reviews and summarises the imaging findings of some of the most important and frequent human parasitic diseases, including information about the parasite's life cycle, pathophysiology, clinical findings, diagnosis, and treatment. We include malaria, amoebiasis, toxoplasmosis, trypanosomiasis, leishmaniasis, echinococcosis, cysticercosis, clonorchiasis, schistosomiasis, fascioliasis, ascariasis, anisakiasis, dracunculiasis, and strongyloidiasis. The aim of this review is to help radiologists when dealing with these diseases or in cases where they are suspected. Teaching Points • Incidence of parasitic diseases is increasing due to migratory movements and travelling. • Some parasitic diseases are still endemic in certain regions in Europe. • Parasitic diseases can have complex life cycles often involving different hosts. • Prompt diagnosis and treatment is essential for patient management in parasitic diseases. • Radiologists should be able to recognise and suspect the most relevant parasitic diseases.

  7. Sex-specific effects of a parasite evolving in a female-biased host population

    Directory of Open Access Journals (Sweden)

    Duneau David

    2012-12-01

    Full Text Available Abstract Background Males and females differ in many ways and might present different opportunities and challenges to their parasites. In the same way that parasites adapt to the most common host type, they may adapt to the characteristics of the host sex they encounter most often. To explore this hypothesis, we characterized host sex-specific effects of the parasite Pasteuria ramosa, a bacterium evolving in naturally, strongly, female-biased populations of its host Daphnia magna. Results We show that the parasite proliferates more successfully in female hosts than in male hosts, even though males and females are genetically identical. In addition, when exposure occurred when hosts expressed a sexual dimorphism, females were more infected. In both host sexes, the parasite causes a similar reduction in longevity and leads to some level of castration. However, only in females does parasite-induced castration result in the gigantism that increases the carrying capacity for the proliferating parasite. Conclusions We show that mature male and female Daphnia represent different environments and reveal one parasite-induced symptom (host castration, which leads to increased carrying capacity for parasite proliferation in female but not male hosts. We propose that parasite induced host castration is a property of parasites that evolved as an adaptation to specifically exploit female hosts.

  8. Fighting while parasitized: can nematode infections affect the outcome of staged combat in beetles?

    Science.gov (United States)

    Vasquez, David; Willoughby, Anna; Davis, Andrew K

    2015-01-01

    The effects of non-lethal parasites may be felt most strongly when hosts engage in intense, energy-demanding behaviors. One such behavior is fighting with conspecifics, which is common among territorial animals, including many beetle species. We examined the effects of parasites on the fighting ability of a saproxylic beetle, the horned passalus (Odontotaenius disjunctus, Family: Passalidae), which is host to a non-lethal nematode, Chondronema passali. We pitted pairs of randomly-chosen (but equally-weighted) beetles against each other in a small arena and determined the winner and aggression level of fights. Then we examined beetles for the presence, and severity of nematode infections. There was a non-significant tendency (p = 0.065) for the frequency of wins, losses and draws to differ between beetles with and without C. passali; non-parasitized individuals (n = 104) won 47% of their fights while those with the parasite (n = 88) won 34%, a 13% difference in wins. The number of nematodes in a beetle affected the outcome of fights between infected and uninfected individuals in an unexpected fashion: fighting ability was lowest in beetles with the lowest (p = 0.033), not highest (p = 0.266), nematode burdens. Within-fight aggression was highest when both beetles were uninfected and lowest when both were infected (p = 0.034). Collectively, these results suggest the nematode parasite, C. passali, is associated with a modest reduction in fighting ability in horned passalus beetles, consistent with the idea that parasitized beetles have lower energy available for fighting. This study adds to a small but growing body of evidence showing how parasites negatively influence fighting behavior in animals.

  9. Fighting while parasitized: can nematode infections affect the outcome of staged combat in beetles?

    Directory of Open Access Journals (Sweden)

    David Vasquez

    Full Text Available The effects of non-lethal parasites may be felt most strongly when hosts engage in intense, energy-demanding behaviors. One such behavior is fighting with conspecifics, which is common among territorial animals, including many beetle species. We examined the effects of parasites on the fighting ability of a saproxylic beetle, the horned passalus (Odontotaenius disjunctus, Family: Passalidae, which is host to a non-lethal nematode, Chondronema passali. We pitted pairs of randomly-chosen (but equally-weighted beetles against each other in a small arena and determined the winner and aggression level of fights. Then we examined beetles for the presence, and severity of nematode infections. There was a non-significant tendency (p = 0.065 for the frequency of wins, losses and draws to differ between beetles with and without C. passali; non-parasitized individuals (n = 104 won 47% of their fights while those with the parasite (n = 88 won 34%, a 13% difference in wins. The number of nematodes in a beetle affected the outcome of fights between infected and uninfected individuals in an unexpected fashion: fighting ability was lowest in beetles with the lowest (p = 0.033, not highest (p = 0.266, nematode burdens. Within-fight aggression was highest when both beetles were uninfected and lowest when both were infected (p = 0.034. Collectively, these results suggest the nematode parasite, C. passali, is associated with a modest reduction in fighting ability in horned passalus beetles, consistent with the idea that parasitized beetles have lower energy available for fighting. This study adds to a small but growing body of evidence showing how parasites negatively influence fighting behavior in animals.

  10. Evaluation of anthelmintic resistance in livestock parasites using observational data and hierarchical models

    DEFF Research Database (Denmark)

    Nielsen, Martin Krarup; Vidyashankar, Anand N.; Hanlon, Bret;

    Anthelmintic resistance is an increasing challenge in the control of parasites in livestock. The fecal egg count reduction test (FECRT) is the practical gold standard method for evaluating resistance, but the interpretation is complicated due to high levels of variability. Several factors...... to handle FECRT data obtained from other livestock species, drug types, and parasite species....

  11. Parasitism and calfhood diseases.

    Science.gov (United States)

    Herlich, H; Douvres, F W

    1977-02-01

    That animals can and do acquire an effective immunity against helminth parasites has been demonstrated extensively experimentally, and the fact that domestic animals such as cattle, sheep, and horses become adults while maintaining good health in spite of constant exposure to reinfection long has suggested that immunity must be important to such survival. Although our attempts to date to vaccinate calves against helminth parasites have either failed or been unsatisfactory because of the pathosis induced by the experimental vaccines, the results are not surprising or discouraging. In contrast to the long history of immunization research on bacterial and viral diseases, only within a relatively short time have serious efforts been directed at exploiting hostal immunity for prevention and control of helminthic diseases. Unlike the comparatively simple structures of viruses and bacteria, helminths are complex multicellular animals with vast arrays of antigens and complicated physiological and immunological interactions with their hosts. Much more fundamental information on helminth-bovine interactions, on helminth antigens, and on cattle antibody systems must be developed before progress on control of cattle helminths by vaccination can be meaningful.

  12. Differentiation of lethal and non lethal prostate cancer:PSA and PSA isoforms and kinetics

    Institute of Scientific and Technical Information of China (English)

    H Ballentine Carter

    2012-01-01

    Prostate-specific antigen (PSA) testing for the early diagnosis of prostate cancer has led to a decrease in cancer mortality.However,the high prevalence of low-grade prostate cancer and its long natural history,competing causes of death in older men and treatment patterns of prostate cancer,have led to dramatic overtreatment of the disease.Improved markers of prostate cancer lethality are needed to reduce the overtreatment of prostate cancer that leads to a reduced quality of life without extending life for a high proportion of men.The PSA level prior to treatment is routinely used in multivariable models to predict prostate cancer aggressiveness.PSA isoforms and PSA kinetics have been associated with more aggressive phenotypes,but are not routinely employed as part of prediction tools prior to treatment.PSA kinetics is a valuable marker of lethality post treatment and routinely used in determining the need for salvage therapy.

  13. Ribavirin Protects Syrian Hamsters against Lethal Hantavirus Pulmonary Syndrome — After Intranasal Exposure to Andes Virus

    Science.gov (United States)

    Ogg, Monica; Jonsson, Colleen B.; Camp, Jeremy V.; Hooper, Jay W.

    2013-01-01

    Andes virus, ANDV, harbored by wild rodents, causes the highly lethal hantavirus pulmonary syndrome (HPS) upon transmission to humans resulting in death in 30% to 50% of the cases. As there is no treatment for this disease, we systematically tested the efficacy of ribavirin in vitro and in an animal model. In vitro assays confirmed antiviral activity and determined that the most effective doses were 40 µg/mL and above. We tested three different concentrations of ribavirin for their capability to prevent HPS in the ANDV hamster model following an intranasal challenge. While the highest level of ribavirin (200 mg/kg) was toxic to the hamster, both the middle (100 mg/kg) and the lowest concentration (50 mg/kg) prevented HPS in hamsters without toxicity. Specifically, 8 of 8 hamsters survived intranasal challenge for both of those groups whereas 7 of 8 PBS control-treated animals developed lethal HPS. Further, we report that administration of ribavirin at 50 mg/kg/day starting on days 6, 8, 10, or 12 post-infection resulted in significant protection against HPS in all groups. Administration of ribavirin at 14 days post-infection also provided a significant level of protection against lethal HPS. These data provide in vivo evidence supporting the potential use of ribavirin as a post-exposure treatment to prevent HPS after exposure by the respiratory route. PMID:24217424

  14. Ribavirin Protects Syrian Hamsters against Lethal Hantavirus Pulmonary Syndrome — After Intranasal Exposure to Andes Virus

    Directory of Open Access Journals (Sweden)

    Jay W. Hooper

    2013-11-01

    Full Text Available Andes virus, ANDV, harbored by wild rodents, causes the highly lethal hantavirus pulmonary syndrome (HPS upon transmission to humans resulting in death in 30% to 50% of the cases. As there is no treatment for this disease, we systematically tested the efficacy of ribavirin in vitro and in an animal model. In vitro assays confirmed antiviral activity and determined that the most effective doses were 40 µg/mL and above. We tested three different concentrations of ribavirin for their capability to prevent HPS in the ANDV hamster model following an intranasal challenge. While the highest level of ribavirin (200 mg/kg was toxic to the hamster, both the middle (100 mg/kg and the lowest concentration (50 mg/kg prevented HPS in hamsters without toxicity. Specifically, 8 of 8 hamsters survived intranasal challenge for both of those groups whereas 7 of 8 PBS control-treated animals developed lethal HPS. Further, we report that administration of ribavirin at 50 mg/kg/day starting on days 6, 8, 10, or 12 post-infection resulted in significant protection against HPS in all groups. Administration of ribavirin at 14 days post-infection also provided a significant level of protection against lethal HPS. These data provide in vivo evidence supporting the potential use of ribavirin as a post-exposure treatment to prevent HPS after exposure by the respiratory route.

  15. Mutation Induced Extinction in Finite Populations: Lethal Mutagenesis and Lethal Isolation

    OpenAIRE

    C Scott Wylie; Shakhnovich, Eugene I.

    2012-01-01

    Reproduction is inherently risky, in part because genomic replication can introduce new mutations that are usually deleterious toward fitness. This risk is especially severe for organisms whose genomes replicate “semi-conservatively,” e.g. viruses and bacteria, where no master copy of the genome is preserved. Lethal mutagenesis refers to extinction of populations due to an unbearably high mutation rate (U), and is important both theoretically and clinically, where drugs can extinguish pathoge...

  16. Syn-lethality: an integrative knowledge base of synthetic lethality towards discovery of selective anticancer therapies.

    Science.gov (United States)

    Li, Xue-juan; Mishra, Shital K; Wu, Min; Zhang, Fan; Zheng, Jie

    2014-01-01

    Synthetic lethality (SL) is a novel strategy for anticancer therapies, whereby mutations of two genes will kill a cell but mutation of a single gene will not. Therefore, a cancer-specific mutation combined with a drug-induced mutation, if they have SL interactions, will selectively kill cancer cells. While numerous SL interactions have been identified in yeast, only a few have been known in human. There is a pressing need to systematically discover and understand SL interactions specific to human cancer. In this paper, we present Syn-Lethality, the first integrative knowledge base of SL that is dedicated to human cancer. It integrates experimentally discovered and verified human SL gene pairs into a network, associated with annotations of gene function, pathway, and molecular mechanisms. It also includes yeast SL genes from high-throughput screenings which are mapped to orthologous human genes. Such an integrative knowledge base, organized as a relational database with user interface for searching and network visualization, will greatly expedite the discovery of novel anticancer drug targets based on synthetic lethality interactions. The database can be downloaded as a stand-alone Java application.

  17. Emerging food-borne parasites.

    Science.gov (United States)

    Dorny, P; Praet, N; Deckers, N; Gabriel, S

    2009-08-07

    Parasitic food-borne diseases are generally underrecognised, however they are becoming more common. Globalization of the food supply, increased international travel, increase of the population of highly susceptible persons, change in culinary habits, but also improved diagnostic tools and communication are some factors associated with the increased diagnosis of food-borne parasitic diseases worldwide. This paper reviews the most important emerging food-borne parasites, with emphasis on transmission routes. In a first part, waterborne parasites transmitted by contaminated food such as Cyclospora cayetanensis, Cryptosporidium and Giardia are discussed. Also human fasciolosis, of which the importance has only been recognised in the last decades, with total numbers of reported cases increasing from less than 3000 to 17 million, is looked at. Furthermore, fasciolopsiosis, an intestinal trematode of humans and pigs belongs to the waterborne parasites as well. A few parasites that may be transmitted through faecal contamination of foods and that have received renewed attention, such as Toxoplasma gondii, or that are (re-)emerging, such as Trypanosoma cruzi and Echinococcus spp., are briefly reviewed. In a second part, meat-borne parasite infections are reviewed. Humans get infected by eating raw or undercooked meat infected with cyst stages of these parasites. Meat inspection is the principal method applied in the control of Taenia spp. and Trichinella spp. However, it is often not very sensitive, frequently not practised, and not done for T. gondii and Sarcocystis spp. Meat of reptiles, amphibians and fish can be infected with a variety of parasites, including trematodes (Opisthorchis spp., Clonorchis sinensis, minute intestinal flukes), cestodes (Diphyllobothrium spp., Spirometra), nematodes (Gnathostoma, spp., anisakine parasites), and pentastomids that can cause zoonotic infections in humans when consumed raw or not properly cooked. Another important zoonotic food

  18. A Targetable GATA2-IGF2 Axis Confers Aggressiveness in Lethal Prostate Cancer

    Science.gov (United States)

    Vidal, Samuel J.; Rodriguez-Bravo, Veronica; Quinn, S. Aidan; Rodriguez-Barrueco, Ruth; Lujambio, Amaia; Williams, Estrelania; Sun, Xiaochen; de la Iglesia-Vicente, Janis; Lee, Albert; Readhead, Ben; Chen, Xintong; Galsky, Matthew; Esteve, Berta; Petrylak, Daniel P.; Dudley, Joel T.; Rabadan, Raul; Silva, Jose M.; Hoshida, Yujin; Lowe, Scott W.; Cordon-Cardo, Carlos; Domingo-Domenech, Josep

    2015-01-01

    SUMMARY Elucidating the determinants of aggressiveness in lethal prostate cancer may stimulate therapeutic strategies that improve clinical outcomes. We used experimental models and clinical databases to identify GATA2 as a regulator of chemotherapy resistance and tumorigenicity in this context. Mechanistically, direct upregulation of the growth hormone IGF2 emerged as a mediator of the aggressive properties regulated by GATA2. IGF2 in turn activated IGF1R and INSR as well as a downstream polykinase program. The characterization of this axis prompted a combination strategy whereby dual IGF1R/INSR inhibition restored the efficacy of chemotherapy and improved survival in preclinical models. These studies reveal a GATA2-IGF2 aggressiveness axis in lethal prostate cancer and identify a therapeutic opportunity in this challenging disease. PMID:25670080

  19. 40 CFR 798.5450 - Rodent dominant lethal assay.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 31 2010-07-01 2010-07-01 true Rodent dominant lethal assay. 798.5450 Section 798.5450 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES... lethality, high pregnancy frequency and high implant numbers are recommended. (ii) Age. Healthy,...

  20. Major parasitic diseases of poverty in mainland China: perspectives for better control.

    Science.gov (United States)

    Wang, Jin-Lei; Li, Ting-Ting; Huang, Si-Yang; Cong, Wei; Zhu, Xing-Quan

    2016-08-01

    Significant progress has been made in the prevention, control, and elimination of human parasitic diseases in China in the past 60 years. However, parasitic diseases of poverty remain major causes of morbidity and mortality, and inflict enormous economic costs on societies.In this article, we review the prevalence rates, geographical distributions, epidemic characteristics, risk factors, and clinical manifestations of parasitic diseases of poverty listed in the first issue of the journal Infectious Diseases of Poverty on 25 October 2012. We also address the challenges facing control of parasitic diseases of poverty and provide suggestions for better control.

  1. [Control situation and primary task of key parasitic diseases in China].

    Science.gov (United States)

    Lei, Zheng-long; Wang, Li-ying

    2012-02-29

    In the "11th Five-year Plan" period, China unveiled a mid-term planning on the control of the key parasitic diseases, including schistosomiasis, malaria, echinococcosis (hydatid disease), as well as some other parasitic diseases. It clarifies the goals on the control of the major parasitic diseases in the national control program during the "12th Five-year' Plan" period (2011-2015) , formulates current main tasks based on analyzing the progress of the national control program on key parasitic diseases, in order to meet the challenges appearing in the future implementation.

  2. Repetitive elements in parasitic protozoa

    Directory of Open Access Journals (Sweden)

    Clayton Christine

    2010-05-01

    Full Text Available Abstract A recent paper published in BMC Genomics suggests that retrotransposition may be active in the human gut parasite Entamoeba histolytica. This adds to our knowledge of the various types of repetitive elements in parasitic protists and the potential influence of such elements on pathogenicity. See research article http://www.biomedcentral.com/1471-2164/11/321

  3. Two types of parasitic assimilation

    Directory of Open Access Journals (Sweden)

    Peter Jurgec

    2013-02-01

    Full Text Available This paper shows that consonant harmony and parasitic vowel harmony are more similar than previously assumed. I provide a unified and restrictive analysis of parasitic assimilation using feature spreading constraints. In particular, I attribute the differences between the attested and unattested patterns to two types of markedness constraints—alignment and agreement.

  4. Parasitic zoonotic diseases in Turkey

    Directory of Open Access Journals (Sweden)

    Nazmiye Altintas

    2008-12-01

    Full Text Available Zoonoses and zoonotic diseases are becoming more common and they are now receiving increased attention across the world. Zoonotic parasites are found in a wide variety of protozoa, cestodes, nematodes, trematodes and arthropods worldwide and many zoonotic parasites have assumed an important role. The importance of some parasitic zoonoses has increased in recent years due to the fact that they can be agents of opportunistic infections. Although a number of zoonotic parasites are often found and do cause serious illnesses in Turkey, some are more common and these diseases are more important as they cause serious public health problems, such as leishmaniasis, toxoplasmosis, cryptosporidiosis, echinococcosis, trichinellosis and toxocariasis. Information on these zoonotic diseases is provided here as these are the most important zoonotic parasitic diseases in Turkey.

  5. Regulatory T Cells and Parasites

    Directory of Open Access Journals (Sweden)

    TP. Velavan

    2011-01-01

    Full Text Available Human host encounters a wide array of parasites; however, the crucial aspect is the failure of the host immune system to clear these parasites despite antigen recognition. In the recent past, a new immunological concept has emerged, which provides a framework to better understand several aspects of host susceptibility to parasitic infection. It is widely believed that parasites are able to modulate the magnitude of effector responses by inducing regulatory T cell (Tregs population and several studies have investigated whether this cell population plays a role in balancing protective immunity and pathogenesis during parasite infection. This review discusses the several mechanism of Treg-mediated immunosuppression in the human host and focuses on the functional role of Tregs and regulatory gene polymorphisms in infectious diseases.

  6. Navigating parasite webs and parasite flow: emerging and re-emerging parasitic zoonoses of wildlife origin.

    Science.gov (United States)

    Polley, Lydden

    2005-10-01

    Wildlife are now recognised as an important source of emerging human pathogens, including parasites. This paper discusses the linkages between wildlife, people, zoonotic parasites and the ecosystems in which they co-exist, revisits definitions for 'emerging' and 're-emerging', and lists zoonotic parasites that can be acquired from wildlife including, for some, estimates of the associated global human health burdens. The paper also introduces the concepts of 'parasite webs' and 'parasite flow', provides a context for parasites, relative to other infectious agents, as causes of emerging human disease, and discusses drivers of disease emergence and re-emergence, especially changes in biodiversity and climate. Angiostrongylus cantonensis in the Caribbean and the southern United States, Baylisascaris procyonis in California and Georgia, Plasmodium knowlesi in Sarawak, Malaysia, Human African Trypanosomiasis, Sarcoptes scabiei in carnivores, and Cryptosporidium, Giardia and Toxoplasma in marine ecosystems are presented as examples of wildlife-derived zoonotic parasites of particular recent interest. An ecological approach to disease is promoted, as is a need for an increased profile for this approach in undergraduate and graduate education in the health sciences. Synergy among scientists and disciplines is identified as critical for the study of parasites and parasitic disease in wildlife populations. Recent advances in techniques for the investigation of parasite fauna of wildlife are presented and monitoring and surveillance systems for wildlife disease are discussed. Some of the limitations inherent in predictions for the emergence and re-emergence of infection and disease associated with zoonotic parasites of wildlife are identified. The importance of public awareness and public education in the prevention and control of emerging and re-emerging zoonotic infection and disease are emphasised. Finally, some thoughts for the future are presented.

  7. Life in cells, hosts, and vectors: parasite evolution across scales.

    Science.gov (United States)

    Mideo, Nicole; Acosta-Serrano, Alvaro; Aebischer, Toni; Brown, Mark J F; Fenton, Andy; Friman, Ville-Petri; Restif, Olivier; Reece, Sarah E; Webster, Joanne P; Brown, Sam P

    2013-01-01

    Parasite evolution is increasingly being recognized as one of the most important issues in applied evolutionary biology. Understanding how parasites maximize fitness whilst facing the diverse challenges of living in cells, hosts, and vectors, is central to disease control and offers a novel testing ground for evolutionary theory. The Centre for Immunity, Infection, and Evolution at the University of Edinburgh recently held a symposium to address the question "How do parasites maximise fitness across a range of biological scales?" The symposium brought together researchers whose work looks across scales and environments to understand why and how parasites 'do what they do', tying together mechanism, evolutionary explanations, and public health implications. With a broad range of speakers, our aim was to define and encourage more holistic approaches to studying parasite evolution. Here, we present a synthesis of the current state of affairs in parasite evolution, the research presented at the symposium, and insights gained through our discussions. We demonstrate that such interdisciplinary approaches are possible and identify key areas for future progress.

  8. [Parasitic factor and cancer].

    Science.gov (United States)

    Khamidullin, R I; Aglullin, I R; Rakhmanin, Iu A; Pogorel'tsev, V I; Khamidullin, A R; Galkina, I V; Khamidullin, I R; Sultanaeva, E G

    2011-01-01

    There is opinion in the literature as to that liver trematode infections, such as opisthorchiasis, clonorchiasis, fascioliasis, and metorchiasis, can induce cancer of the liver pancreas, intestine - this all is clinically observed. The authors were the first in world practice to show the development of a hepatic blastomatous process in animals (albino rats, cats) with opisthorchiasis in 13%; cancer developed in 28 and 56% with the use of a hepatotropic carcinogen and combined (opisthorchiasis + a carcinogen) exposure, respectively. Throughout his life, a human being can easily catch these trematodes that have carcinogenic activity and these diseases concurrent with household and food carcinogens can give rise to tumors in the liver pancreas and intestine. Timely diagnosis and specific anthelmintic therapy are necessary to prevent parasitic cancer.

  9. Integrated parasite management

    DEFF Research Database (Denmark)

    Clausen, Jesper Hedegaard; Madsen, Henry; Van, Phan Thi

    2015-01-01

    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 ...... 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...

  10. Antidotes to anthrax lethal factor intoxication. Part 1: Discovery of potent lethal factor inhibitors with in vivo efficacy.

    Science.gov (United States)

    Jiao, Guan-Sheng; Kim, Seongjin; Moayeri, Mahtab; Cregar-Hernandez, Lynne; McKasson, Linda; Margosiak, Stephen A; Leppla, Stephen H; Johnson, Alan T

    2010-11-15

    Sub-nanomolar small molecule inhibitors of anthrax lethal factor have been identified using SAR and Merck L915 (4) as a model compound. One of these compounds (16) provided 100% protection in a rat lethal toxin model of anthrax disease.

  11. Lethal and sub-lethal effects of five pesticides used in rice farming on the earthworm Eisenia fetida

    NARCIS (Netherlands)

    Rico, Andreu; Sabater, Consuelo; Castillo, María Ángeles

    2016-01-01

    The toxicity of five pesticides typically used in rice farming (trichlorfon, dimethoate, carbendazim, tebuconazole and prochloraz) was evaluated on different lethal and sub-lethal endpoints of the earthworm Eisenia fetida. The evaluated endpoints included: avoidance behaviour after an exposure pe

  12. A Burkholderia pseudomallei outer membrane vesicle vaccine provides protection against lethal sepsis.

    Science.gov (United States)

    Nieves, Wildaliz; Petersen, Hailey; Judy, Barbara M; Blumentritt, Carla A; Russell-Lodrigue, Kasi; Roy, Chad J; Torres, Alfredo G; Morici, Lisa A

    2014-05-01

    The environmental Gram-negative encapsulated bacillus Burkholderia pseudomallei is the causative agent of melioidosis, a disease associated with high morbidity and mortality rates in areas of Southeast Asia and northern Australia in which the disease is endemic. B. pseudomallei is also classified as a tier I select agent due to the high level of lethality of the bacterium and its innate resistance to antibiotics, as well as the lack of an effective vaccine. Gram-negative bacteria, including B. pseudomallei, secrete outer membrane vesicles (OMVs) which are enriched with multiple protein, lipid, and polysaccharide antigens. Previously, we demonstrated that immunization with multivalent B. pseudomallei-derived OMVs protects highly susceptible BALB/c mice against an otherwise lethal aerosol challenge. In this work, we evaluated the protective efficacy of OMV immunization against intraperitoneal challenge with a heterologous strain because systemic infection with phenotypically diverse environmental B. pseudomallei strains poses another hazard and a challenge to vaccine development. We demonstrated that B. pseudomallei OMVs derived from strain 1026b afforded significant protection against septicemic infection with B. pseudomallei strain K96243. OMV immunization induced robust OMV-, lipopolysaccharide-, and capsular polysaccharide-specific serum IgG (IgG1, IgG2a, and IgG3) and IgM antibody responses. OMV-immune serum promoted bacterial killing in vitro, and passive transfer of B. pseudomallei OMV immune sera protected naive mice against a subsequent challenge. These results indicate that OMV immunization provides antibody-mediated protection against acute, rapidly lethal sepsis in mice. B. pseudomallei-derived OMVs may represent an efficacious multivalent vaccine strategy against melioidosis.

  13. Presence of virus neutralizing antibodies in cerebral spinal fluid correlates with non-lethal rabies in dogs.

    Directory of Open Access Journals (Sweden)

    Clement W Gnanadurai

    Full Text Available Rabies is traditionally considered a uniformly fatal disease after onset of clinical manifestations. However, increasing evidence indicates that non-lethal infection as well as recovery from flaccid paralysis and encephalitis occurs in laboratory animals as well as humans.Non-lethal rabies infection in dogs experimentally infected with wild type dog rabies virus (RABV, wt DRV-Mexico correlates with the presence of high level of virus neutralizing antibodies (VNA in the cerebral spinal fluid (CSF and mild immune cell accumulation in the central nervous system (CNS. By contrast, dogs that succumbed to rabies showed only little or no VNA in the serum or in the CSF and severe inflammation in the CNS. Dogs vaccinated with a rabies vaccine showed no clinical signs of rabies and survived challenge with a lethal dose of wild-type DRV. VNA was detected in the serum, but not in the CSF of immunized dogs. Thus the presence of VNA is critical for inhibiting virus spread within the CNS and eventually clearing the virus from the CNS.Non-lethal infection with wt RABV correlates with the presence of VNA in the CNS. Therefore production of VNA within the CNS or invasion of VNA from the periphery into the CNS via compromised blood-brain barrier is important for clearing the virus infection from CNS, thereby preventing an otherwise lethal rabies virus infection.

  14. Tumor clone dynamics in lethal prostate cancer.

    Science.gov (United States)

    Carreira, Suzanne; Romanel, Alessandro; Goodall, Jane; Grist, Emily; Ferraldeschi, Roberta; Miranda, Susana; Prandi, Davide; Lorente, David; Frenel, Jean-Sebastien; Pezaro, Carmel; Omlin, Aurelius; Rodrigues, Daniel Nava; Flohr, Penelope; Tunariu, Nina; S de Bono, Johann; Demichelis, Francesca; Attard, Gerhardt

    2014-09-17

    It is unclear whether a single clone metastasizes and remains dominant over the course of lethal prostate cancer. We describe the clonal architectural heterogeneity at different stages of disease progression by sequencing serial plasma and tumor samples from 16 ERG-positive patients. By characterizing the clonality of commonly occurring deletions at 21q22, 8p21, and 10q23, we identified multiple independent clones in metastatic disease that are differentially represented in tissue and circulation. To exemplify the clinical utility of our studies, we then showed a temporal association between clinical progression and emergence of androgen receptor (AR) mutations activated by glucocorticoids in about 20% of patients progressing on abiraterone and prednisolone or dexamethasone. Resistant clones showed a complex dynamic with temporal and spatial heterogeneity, suggesting distinct mechanisms of resistance at different sites that emerged and regressed depending on treatment selection pressure. This introduces a management paradigm requiring sequential monitoring of advanced prostate cancer patients with plasma and tumor biopsies to ensure early discontinuation of agents when they become potential disease drivers.

  15. 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.

  16. Lesser of Two Evils? Foraging Choices in Response to Threats of Predation and Parasitism

    Science.gov (United States)

    Koprivnikar, Janet; Penalva, Laura

    2015-01-01

    Predators have documented post-encounter (density-mediated) effects on prey but their pre-encounter impacts, including behavioural alterations, can be substantial as well. While it is increasingly evident that this “ecology of fear” is important to understand for natural enemy-victim relationships, fear responses of hosts to the threat of infection by a parasite are relatively unknown. We examined larval amphibian (Lithobates pipiens) foraging choices by experimentally manipulating the presence of cues relating to predator (larval odonate) or parasite (the trematode Ribeiroia ondatrae) threats. Tadpoles avoided foraging where predator or parasite cues were present; however, they did not treat these as equal hazards. When both threats were simultaneously present, tadpoles strongly preferred to forage under the threat of parasitism compared to predation, likely driven by their relative lethality in our study. Our results indicate that altered spatial use is an important anti-parasite behaviour, and demonstrate that parasite avoidance can affect foraging in a manner similar to predators, warranting greater study of the pre-encounter effects of this enemy type. PMID:25635765

  17. Do molecules matter more than morphology? Promises and pitfalls in parasites.

    Science.gov (United States)

    Perkins, S L; Martinsen, E S; Falk, B G

    2011-11-01

    Systematics involves resolving both the taxonomy and phylogenetic placement of organisms. We review the advantages and disadvantages of the two kinds of information commonly used for such inferences--morphological and molecular data--as applied to the systematics of metazoan parasites generally, with special attention to the malaria parasites. The problems that potentially confound the use of morphology in parasites include challenges to consistent specimen preservation, plasticity of features depending on hosts or other environmental factors, and morphological convergence. Molecular characters such as DNA sequences present an alternative data source and are particularly useful when not all the parasite's life stages are present or when parasitaemia is low. Nonetheless, molecular data can bring challenges that include troublesome DNA isolation, paralogous gene copies, difficulty in developing molecular markers, and preferential amplification in mixed species infections. Given the differential benefits and shortcomings of both molecular and morphological characters, both should be implemented in parasite taxonomy and phylogenetics.

  18. 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.

  19. Lethal and sub lethal effects of the biocide chlorhexidine on aquatic organisms.

    Science.gov (United States)

    Jesus, Fátima T; Oliveira, Rhaul; Silva, Andreia; Catarino, Ana L; Soares, Amadeu M V M; Nogueira, António J A; Domingues, Inês

    2013-11-01

    Chlorhexidine is among the most used biocides in Europe, however its toxicity to aquatic organisms is scarcely known. The main objective of this study was to assess the lethal and sub lethal effects of chlorhexidine digluconate (ChD) on four aquatic model organisms: the bacteria Vibrio fischeri, the algae Pseudokirchneriella subcapitata, the crustacean Daphnia magna and the embryos of the fish Danio rerio. ChD was very toxic to algae and crustaceans, with a 72 h-EC50 of 62.2 μg/l and a 48 h-EC50 of 45.0 μg/l, respectively. Toxicity to fish embryos and the bacteria was lower, with a 96 h-EC50 of 804.0 μg/l and a 15 min-EC50 of 1,694.0 μg/l, respectively. Concerning sub lethal effects on D. magna (feeding inhibition) a 6 h-EC50 of 503.7 μg/l was obtained. In fish, ChD caused developmental abnormalities, namely alterations in the amniotic fluid (48 h-EC20 of 753.6 μg/l) and early hatching. Moreover, enzymatic biomarkers on fish embryos showed an induction of cholinesterase activity in all ChD tested concentrations (80-900 μg/l). The catalase activity was also induced at the highest concentration tested (900 μg/l) whereas no changes were observed for glutathione-S-transferase and lactate dehydrogenase activities. The toxicity of ChD to the algae and crustacean raises concerns about its potential effects in aquatic food webs, since these organisms are in the base of trophic chains, and highlights the need for further studies on ChD toxicity to aquatic organisms.

  20. Parasites in algae mass culture

    Directory of Open Access Journals (Sweden)

    Todd William Lane

    2014-06-01

    Full Text Available Parasites are now known to be ubiquitous across biological systems and can play an important role in modulating algal populations. However, there is a lack of extensive information on their role in artificial ecosystems such as algal production ponds and photobioreactors. Parasites have been implicated in the demise of algal blooms. Because individual mass culture systems often tend to be unialgal and a select few algal species are in wide scale application, there is an increased potential for parasites to have a devastating effect on commercial scale monoculture. As commercial algal production continues to expand with a widening variety of applications, including biofuel, food and pharmaceuticals, the parasites associated with algae will become of greater interest and potential economic impact. A number of important algal parasites have been identified in algal mass culture systems in the last few years and this number is sure to grow as the number of commercial algae ventures increases. Here, we review the research that has identified and characterized parasites infecting mass cultivated algae, the techniques being proposed and or developed to control them, and the potential impact of parasites on the future of the algal biomass industry.

  1. Cognitive Inhibition in Elderly High-Lethality Suicide Attempters

    Science.gov (United States)

    Richard-Devantoy, Stéphane; Szanto, Katalin; Butters, Meryl A.; Kalkus, Jan; Dombrovski, Alexandre Y.

    2014-01-01

    Background People who attempt suicide often display cognitive impairments, particularly poor cognitive control. Could poor cognitive control contribute to high suicide rates in old age? A component of cognitive control, cognitive inhibition – active suppression of task-irrelevant processing – is very sensitive to aging and has been linked to attempted suicide. We investigated cognitive inhibition in older high-lethality suicide attempters, closely resembling suicide victims, as well as low-lethality attempters, and control groups with and without depression and suicidal ideation. Methods 102 participants aged 60+ (17 psychiatrically healthy control subjects, 38 depressed control subjects, 16 suicide ideators, 14 low-lethality suicide attempters, and 17 high-lethality suicide attempters) underwent comprehensive clinical and cognitive assessments. They completed the Delis–Kaplan Executive Function System Color-Word Interference Test, a validated modification of the Stroop test. Results High-lethality suicide attempters demonstrated a distinct pattern of cognitive inhibition deficits. Compared to psychiatrically healthy control subjects and suicide ideators, high-lethality attempters took longer to complete inhibition trials, even after accounting for potential confounding factors (age, education, MMSE score, information processing speed, and accuracy). Compared to non-suicidal depressed and healthy control subjects, low-lethality suicide attempters committed more uncorrected errors; however, this difference was not specific to the inhibition condition. Conclusions Older suicide attempters are a cognitively heterogeneous group. Poor cognitive control in high-lethality attempters may undermine their ability to solve real-life problems, precipitating a catastrophic accumulation of stressors. Meanwhile, low-lethality attempters' poor performance may reflect a careless approach to the task or faulty monitoring. PMID:24816626

  2. Are high-lethality suicide attempters with bipolar disorder a distinct phenotype?

    Science.gov (United States)

    Oquendo, Maria A; Carballo, Juan Jose; Rajouria, Namita; Currier, Dianne; Tin, Adrienne; Merville, Jessica; Galfalvy, Hanga C; Sher, Leo; Grunebaum, Michael F; Burke, Ainsley K; Mann, J John

    2009-01-01

    Because Bipolar Disorder (BD) individuals making highly lethal suicide attempts have greater injury burden and risk for suicide, early identification is critical. BD patients were classified as high- or low-lethality attempters. High-lethality attempts required inpatient medical treatment. Mixed effects logistic regression models and permutation analyses examined correlations between lethality, number, and order of attempts. High-lethality attempters reported greater suicidal intent and more previous attempts. Multiple attempters showed no pattern of incremental lethality increase with subsequent attempts, but individuals with early high-lethality attempts more often made high-lethality attempts later. A subset of high-lethality attempters make only high-lethality attempts. However, presence of previous low-lethality attempts does not indicate that risk for more lethal, possibly successful, attempts is reduced.

  3. A transgenic Plasmodium falciparum NF54 strain that expresses GFP-luciferase throughout the parasite life cycle.

    Science.gov (United States)

    Vaughan, Ashley M; Mikolajczak, Sebastian A; Camargo, Nelly; Lakshmanan, Viswanathan; Kennedy, Mark; Lindner, Scott E; Miller, Jessica L; Hume, Jen C C; Kappe, Stefan H I

    2012-12-01

    Plasmodium falciparum is the pathogenic agent of the most lethal of human malarias. Transgenic P. falciparum parasites expressing luciferase have been created to study drug interventions of both asexual and sexual blood stages but luciferase-expressing mosquito stage and liver stage parasites have not been created which has prevented the easy quantification of mosquito stage development (e.g. for transmission blocking interventions) and liver stage development (for interventions that prevent infection). To overcome this obstacle, we have created a transgenic P. falciparum NF54 parasite that expresses a GFP-luciferase transgene throughout the life cycle. Luciferase expression is robust and measurable at all life cycle stages, including midgut oocyst, salivary gland sporozoites and liver stages, where in vivo development is easily measurable using humanized mouse infections in conjunction with an in vivo imaging system. This parasite reporter strain will accelerate testing of interventions against pre-erythrocytic life cycle stages.

  4. Parasites on parasites: coupled fluctuations in stacked contact processes

    CERN Document Server

    Court, Steven J; Allen, Rosalind J

    2012-01-01

    We present a model for host-parasite dynamics which incorporates both vertical and horizontal transmission as well as spatial structure. Our model consists of stacked contact processes (CP), where the dynamics of the host is a simple CP on a lattice while the dynamics of the parasite is a secondary CP which sits on top of the host-occupied sites. In the simplest case, where infection does not incur any cost, we uncover a novel effect: a nonmonotonic dependence of parasite prevalence on host turnover. Inspired by natural examples of hyperparasitism, we extend our model to multiple levels of parasites and identify a transition between the maintenance of a finite and infinite number of levels, which we conjecture is connected to a roughening transition in models of surface-growth.

  5. Leishmaniasis–HIV coinfection: current challenges

    Directory of Open Access Journals (Sweden)

    Lindoso JAL

    2016-10-01

    Full Text Available José Angelo Lauletta Lindoso,1,2 Mirella Alves Cunha,3 Igor Thiago Queiroz,4 Carlos Henrique Valente Moreira2 1Laboratory of Soroepidemiology (LIM HC-FMUSP, São Paulo University, São Paulo, 2Instituto de Infectologia Emilio Ribas-SES, São Paulo, 3Department of Infectious Disease, Faculty of Medicine, São Paulo University, São Paulo, 4Hospital Giselda Trigueiro - SESAP, Natal, Brazil Abstract: Leishmaniasis – human immunodeficiency virus (HIV coinfection can manifest itself as tegumentary or visceral leishmaniasis. Almost 35 countries have reported autochthonous coinfections. Visceral leishmaniasis is more frequently described. However, usual and unusual manifestations of tegumentary leishmaniasis have been reported mainly in the Americas, but the real prevalence of Leishmania infection in HIV-infected patients is not clear. Regarding the clinical manifestations, there are some reports showing unusual manifestations in visceral leishmaniasis and tegumentary leishmaniasis in HIV-infected patients; yet, the usual manifestations are more frequent. Leishmaniasis diagnosis relies on clinical methods, but serological tests are used to diagnose visceral leishmaniasis despite them having a low sensitivity to tegumentary leishmaniasis. The search for the parasite is used to diagnose both visceral leishmaniasis and tegumentary leishmaniasis. Nevertheless, in HIV-infected patients, the sensitivity of serology is very low. Drugs available to treat leishmaniasis are more restricted and cause severe side effects. Furthermore, in HIV-infected patients, these side effects are more prominent and relapses and lethality are more recurrent. In this article, we discuss the current challenges of tegumentary leishmaniasis and visceral leishmaniasis–HIV infection, focusing mainly on the clinical manifestations, diagnosis, and treatment of leishmaniasis. Keywords: leishmaniasis, HIV infection, coinfection, epidemiology, clinical manifestations, diagnosis

  6. Lethal and sub-lethal responses of native freshwater mussels exposed to granular Bayluscide®, a sea lamprey larvicide

    Science.gov (United States)

    Newton, Teresa; Boogaard, Michael A.; Gray, Brian R.; Hubert, Terrance D.; Schloesser, Nicholas

    2017-01-01

    The invasive sea lamprey (Petromyzon marinus) poses a substantial threat to fish communities in the Great Lakes. Efforts to control sea lamprey populations typically involve treating tributary streams with lampricides on a recurring cycle. The presence of a substantial population of larval sea lampreys in the aquatic corridor between Lakes Huron and Erie prompted managers to propose a treatment using the granular formulation of Bayluscide® that targets larval sea lampreys that reside in sediments. However, these treatments could cause adverse effects on native freshwater mussels—imperiled animals that also reside in sediments. We estimated the risk of mortality and sub-lethal effects among eight species of adult and sub-adult mussels exposed to Bayluscide® for durations up to 8 h to mimic field applications. Mortality was appreciable in some species, especially in sub-adults (range, 23–51%). The lethal and sub-lethal effects were positively associated with the duration of exposure in most species and life stage combinations. Estimates of the median time of exposure that resulted in lethal and sub-lethal effects suggest that sub-adults were often affected by Bayluscide® earlier than adults. Siphoning activity and burrowing position of mussels during exposure may have moderated the uptake of Bayluscide® and may have influenced lethal and sub-lethal responses. Given that the various species and life stages were differentially affected, it will be difficult to predict the effects of Bayluscide® treatments on mussels.

  7. Synanthropic birds and parasites.

    Science.gov (United States)

    Dipineto, Ludovico; Borrelli, Luca; Pepe, Paola; Fioretti, Alessandro; Caputo, Vincenzo; Cringoli, Giuseppe; Rinaldi, Laura

    2013-12-01

    This paper describes the parasitologic findings for 60 synanthropic bird carcasses recovered in the Campania region of southern Italy. Birds consisted of 20 yellow-legged gulls (Larus michahellis), 15 rock pigeons (Columba livia), 15 common kestrels (Falco tinnunculus), and 10 carrion crows (Corvus corone). Each carcass was examined to detect the presence of ectoparasites and then necropsied to detect helminths. Ectoparasites occurred in 100% of the birds examined. In particular, chewing lice were recovered with a prevalence of 100%, whereas Pseudolynchia canariensis (Hippoboscidae) were found only in pigeons with a prevalence of 80%. Regarding endoparasites, a total of seven helminth species were identified: three nematodes (Ascaridia columbae, Capillaria columbae, Physaloptera alata), one cestoda (Raillietina tetragona), one trematoda (Cardiocephalus longicollis), and two acanthocephalans (Centrorhynchus globocaudatus and Centrorhynchus buteonis). The findings of the present study add data to the parasitologic scenario of synanthropic birds. This is important because parasitic infection can lead to serious health problems when combined with other factors and may affect flying performance and predatory effectiveness.

  8. Parasites in pet reptiles

    Science.gov (United States)

    2011-01-01

    Exotic reptiles originating from the wild can be carriers of many different pathogens and some of them can infect humans. Reptiles imported into Slovenia from 2000 to 2005, specimens of native species taken from the wild and captive bred species were investigated. A total of 949 reptiles (55 snakes, 331 lizards and 563 turtles), belonging to 68 different species, were examined for the presence of endoparasites and ectoparasites. Twelve different groups (Nematoda (5), Trematoda (1), Acanthocephala (1), Pentastomida (1) and Protozoa (4)) of endoparasites were determined in 26 (47.3%) of 55 examined snakes. In snakes two different species of ectoparasites were also found. Among the tested lizards eighteen different groups (Nematoda (8), Cestoda (1), Trematoda (1), Acanthocephala (1), Pentastomida (1) and Protozoa (6)) of endoparasites in 252 (76.1%) of 331 examined animals were found. One Trombiculid ectoparasite was determined. In 563 of examined turtles eight different groups (Nematoda (4), Cestoda (1), Trematoda (1) and Protozoa (2)) of endoparasites were determined in 498 (88.5%) animals. In examined turtles three different species of ectoparasites were seen. The established prevalence of various parasites in reptiles used as pet animals indicates the need for examination on specific pathogens prior to introduction to owners. PMID:21624124

  9. MENGENAL PARASIT FILARIA

    Directory of Open Access Journals (Sweden)

    Tri Ramadhani

    2012-11-01

    Full Text Available Filariasis atau kaki gajah adalah penyakit menular yang disebabkan karena infeksi cacing filaria yang hidup disaluran dan kelenjar getah bening (limfe serta menyebabkan gejala akut, kronis. Filariasis mulai dikenal di Indonesia tahun 1889 sejak Haga dan Van Eecke menemukan kasus pembesaran scrotum di Jakarta. Penyakit tersebut dapat menular kepada orang lain dengan perantara gigitan nyamuk. Seluruh wilayah Indonesia berpotensi untuk terjangkitnya penyakit tersebut, hal ini mengingat cacing sebagai penyebabnya dan nyamuk penularnya tersebar luas. Keadaan ini didukung oleh kerusakan lingkungan, seperti banjir, penebangan hutan dan lainnya yang memperluas tempat berkembangbiaknya nyamuk. Meskipun filariasis tidak mematikan secara langsung, dengan adanya demam dan bisul-bisul (abses yang hilang timbul, dan gejala menahun berupa pembesaran/elefantiasis yang merupakan cacat menetap akan sangat mengganggu. Secara ekonomis keadaan tersebut sangat merugikan, karena mengurangi produktivitas masyarakat, serta diperlukan biaya pengobatan dan perawatan yang tidak mudah dan tidak murah.Di Indonesia filariasis limfatik di sebabkan oleh tiga spesies cacing filaria yaitu Brugia malayi,B.timori dan Wuchereria bancrofti, yang terbagi lagi menjadi 6 tipe secara epidemiologi.Tiap parasit mempunyai siklus hidup yang kompleks dan infeksi pada manusia tidak akan berhasil kecuali jika terjadi pemaparan larva infektif untuk waktu yang lama. Setelah terjadi pemaparan, dibutuhkan waktu bertahun-tahun sebelum timbulnya perubahan patologis yang nyata pada manusia. Periodisitas dalam sirkulasi setiap mikrofilaria akan berbeda, tergantung dari spesiesnya.

  10. Tropical parasitic diseases and women.

    Science.gov (United States)

    Okwa, O O

    2007-12-01

    Tropical parasitic diseases constitute the greatest threat to the health and socio-economic status of women as a gender and social group. There are some gender specific ways in which parasitic diseases affect women in contrast to men due to differences in exposure, occupational risk, sociocultural behavior, gender roles and practices. These parasitic diseases confer some social stigma, which affects the health seeking behavior of women. Women are therefore important in the control of these parasitic diseases and they are key agents of change, if they are included in community control programs. Women need more attention in endemic areas as a group that had been neglected. This deprived and excluded group have got vital role to play, as discussed in this review.

  11. Fentanyl-Laced 'Norco' Is Lethal, Report Warns

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_160158.html Fentanyl-Laced 'Norco' Is Lethal, Report Warns New street ... study involving the drug. The street drug combines fentanyl -- the synthetic opioid painkiller linked to the death ...

  12. New type of lethal short-limbed dwarfism

    Energy Technology Data Exchange (ETDEWEB)

    Nairn, E.R.; Chapman, S.

    1989-05-01

    Details are presented of a most unusual osteo-chondrodysplasia which presents with lethal neonatal short-limbed dwarfism, defective ossification and nodular calcification with cartilage. The features resemble one case previously described in the literature.

  13. Pervasiveness of parasites in pollinators.

    Science.gov (United States)

    Evison, Sophie E F; Roberts, Katherine E; Laurenson, Lynn; Pietravalle, Stéphane; Hui, Jeffrey; Biesmeijer, Jacobus C; Smith, Judith E; Budge, Giles; Hughes, William O H

    2012-01-01

    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.

  14. Molecular diagnostics and parasitic disease.

    Science.gov (United States)

    Vasoo, Shawn; Pritt, Bobbi S

    2013-09-01

    Molecular parasitology represents an emerging field in microbiology diagnostics. Although most assays use nonstandardized, laboratory-developed methods, a few commercial systems have recently become available and are slowly being introduced into larger laboratories. In addition, a few methodologies show promise for use in field settings in which parasitic infections are endemic. This article reviews the available techniques and their applications to major parasitic diseases such as malaria, leishmaniasis, and trichomoniasis.

  15. Parasites and altruism: converging roads.

    Science.gov (United States)

    Zuk, Marlene; Borrello, Mark E

    2013-01-01

    W.D. Hamilton was most known for his work on two topics: social evolution and parasites. Although at first glance these seem to be disparate interests, they share many attributes and have logical connections within evolutionary biology. Nevertheless, Hamilton's contributions in these areas met with very different receptions, with his place in the field of social evolution assured, but his work on the role of parasites perceived as more specialized. We take an historical approach to examine the reasons for this difference.

  16. 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.

  17. Parasitic Effects on Memristor Dynamics

    Science.gov (United States)

    Itoh, Makoto; Chua, Leon O.

    2016-06-01

    In this paper, we show that parasitic elements have a significant effect on the dynamics of memristor circuits. We first show that certain 2-terminal elements such as memristors, memcapacitors, and meminductors can be used as nonvolatile memories, if the principle of conservation of state variables hold by open-circuiting, or short-circuiting, their terminals. We also show that a passive memristor with a strictly-increasing constitutive relation will eventually lose its stored flux when we switch off the power if there is a parasitic capacitance across the memristor. Similarly, a memcapacitor (resp., meminductor) with a positive memcapacitance (resp., meminductance) will eventually lose their stored physical states when we switch off the power, if it is connected to a parasitic resistance. We then show that the discontinuous jump that circuit engineers assumed to occur at impasse points of memristor circuits contradicts the principles of conservation of charge and flux at the time of the discontinuous jump. A parasitic element can be used to break an impasse point, resulting in the emergence of a continuous oscillation in the circuit. We also define a distance, a diameter, and a dimension, for each circuit element in order to measure the complexity order of the parasitic elements. They can be used to find higher-order parasitic elements which can break impasse points. Furthermore, we derived a memristor-based Chua’s circuit from a three-element circuit containing a memristor by connecting two parasitic memcapacitances to break the impasse points. We finally show that a higher-order parasitic element can be used for breaking the impasse points on two-dimensional and three-dimensional constrained spaces.

  18. Ligand-induced expansion of the S1' site in the anthrax toxin lethal factor

    Energy Technology Data Exchange (ETDEWEB)

    Maize, Kimberly M.; Kurbanov, Elbek K.; Johnson, Rodney L.; Amin, Elizabeth Ambrose; Finzel, Barry C. (UMM)

    2016-07-05

    The Bacillus anthracis lethal factor (LF) is one component of a tripartite exotoxin partly responsible for persistent anthrax cytotoxicity after initial bacterial infection. Inhibitors of the zinc metalloproteinase have been investigated as potential therapeutic agents, but LF is a challenging target because inhibitors lack sufficient selectivity or possess poor pharmaceutical properties. These structural studies reveal an alternate conformation of the enzyme, induced upon binding of specific inhibitors, that opens a previously unobserved deep pocket termed S1'* which might afford new opportunities to design selective inhibitors that target this subsite.

  19. Role of pseudorabies virus glycoprotein II in protection from lethal infection.

    Science.gov (United States)

    Nakamura, T; Ihara, T; Nunoya, T; Kuwahara, H; Ishihama, A; Ueda, S

    1993-07-01

    A monoclonal antibody (mAb), named 1.21, with complement-dependent neutralizing activity was produced against glycoprotein II (gII) of pseudorabies virus (PRV). By immunoaffinity chromatography using a mAB 1.21 column, gII was purified from Nonidet P40-lysates of PRV infected BHK21/13 cells. When mice and pigs were immunized with purified gII, complement-dependent virus-neutralizing antibodies were produced. The immunized animals survived potentially lethal challenge with PRV. These results indicate that an immunological response against gII plays an important role in the protection from PRV infection.

  20. Adaptations in the energy metabolism of parasites

    NARCIS (Netherlands)

    van Grinsven, K.W.A.

    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

  1. Adaptations in the energy metabolism of parasites

    NARCIS (Netherlands)

    van Grinsven, K.W.A.

    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

  2. Tachinidae Parasitic on the Lymantriidae in Japan

    OpenAIRE

    Paul W., Schaefer; Hiroshi, SHIMA; Asian Parasite Laboratory, Agricultural Research, Science and Education Administration, U.S. Department of Agriculture:(Present address)Beneficial Insects Research Laboratory; Biological Laboratory, College of General Education, Kyushu University

    1981-01-01

    Recorded tachinid parasites and 23 new host records are listed for 15 lymantriid species in Japan. A parasite-host list is included and a new species of Carcelia parasitic on Leucoma candida in Hokkaido is described and illustrated. A key to adult tachinid parasites of the Lymantriidae in Japan is provided.

  3. Parasitic infections in travelers and immigrants: part I protozoa.

    Science.gov (United States)

    Norman, Francesca F; Monge-Maillo, Begoña; Martínez-Pérez, Ángela; Perez-Molina, Jose A; López-Vélez, Rogelio

    2015-01-01

    The growth in international commerce, travel and migration contribute to the global emergence of certain parasitic infections. Importation of vectors and food products may contribute to the emergence of protozoan infections in nonendemic countries. Infections such as malaria are potentially fatal, especially in nonimmune patients, and outcome depends largely on timely diagnosis and treatment. Diagnosis/management of imported parasitic infections may be complex especially as some patients may have underlying immunosuppressive conditions such as HIV infection. Major challenges concern the development of improved diagnostic techniques, safer/more effective drug therapies and identification of biological markers of progression and response to treatment. Imported parasitic diseases which may be transmitted vertically or through blood transfusion/organ donation could become a public health priority in the near future. Climate change may affect arthropod distribution and facilitate the spread of protozoan vector-borne diseases. The first part of this review focuses on protozoan infections in travelers and immigrants.

  4. RNAi and functional genomics in plant parasitic nematodes.

    Science.gov (United States)

    Rosso, M N; Jones, J T; Abad, P

    2009-01-01

    Plant nematology is currently undergoing a revolution with the availability of the first genome sequences as well as comprehensive expressed sequence tag (EST) libraries from a range of nematode species. Several strategies are being used to exploit this wealth of information. Comparative genomics is being used to explore the acquisition of novel genes associated with parasitic lifestyles. Functional analyses of nematode genes are moving toward larger scale studies including global transcriptome profiling. RNA interference (RNAi) has been shown to reduce expression of a range of plant parasitic nematode genes and is a powerful tool for functional analysis of nematode genes. RNAi-mediated suppression of genes essential for nematode development, survival, or parasitism is revealing new targets for nematode control. Plant nematology in the genomics era is now facing the challenge to develop RNAi screens adequate for high-throughput functional analyses.

  5. Control of human parasitic diseases: Context and overview.

    Science.gov (United States)

    Molyneux, David H

    2006-01-01

    leishmaniases can be solved in the not too distant future. However, it will be difficult to implement and sustain such interventions in fragile health services often in settings where resources are limited but also in unstable, conflict-affected or post-conflict countries. Emphasis is placed on the importance of co-endemicity and polyparasitism and the opportunity to control parasites susceptible to cost-effective and proven chemotherapeutic interventions for a package of diseases which can be implemented at low cost and which would benefit the poorest and most marginalized groups. The ecology of parasitic diseases is discussed in the context of changing ecology, environment, sociopolitical developments and climate change. These drivers of global change will affect the epidemiology of parasites over the coming decades, while in many of the most endemic and impoverished countries parasitic infections will be accorded lower priority as resourced stressed health systems cope with the burden of the higher-profile killing diseases viz., HIV/AIDS, TB and malaria. There is a need for more holistic thinking about the interactions between parasites and other infections. It is clear that as the prevalence and awareness of HIV has increased, there is a growing recognition of a host of complex interactions that determine disease outcome in individual patients. The competition for resources in the health as well as other social sectors will be a continuing challenge; effective parasite control will be dependent on how such resources are accessed and deployed to effectively address well-defined problems some of which are readily amenable to successful interventions with proven methods. In the health sector, the problems of the HIV/AIDS and TB pandemics and the problem of the emerging burden of chronic non-communicable diseases will be significant competitors for these limited resources as parasitic infections aside from malaria tend to be chronic disabling problems of the poorest who have

  6. Perinatal-lethal Gaucher disease presenting as hydrops fetalis.

    Science.gov (United States)

    BenHamida, Emira; Ayadi, Imene; Ouertani, Ines; Chammem, Maroua; Bezzine, Ahlem; BenTmime, Riadh; Attia, Leila; Mrad, Ridha; Marrakchi, Zahra

    2015-01-01

    Perinatal-lethal Gaucher disease is very rare and is considered a variant of type 2 Gaucher disease that occurs in the neonatal period. The most distinct features of perinatal-lethal Gaucher disease are non-immune hydrops fetalis. Less common signs of the disease are hepatosplenomegaly, ichthyosis and arthrogryposis. We report a case of Gaucher's disease (type 2) diagnosed in a newborn who presented with Hydrops Fetalis.

  7. Testicular trauma secondary to less-lethal kinetic energy munitions.

    Science.gov (United States)

    Kavoussi, Parviz K; Hermans, Michael R

    2006-06-01

    Many cases of testicular trauma secondary to munitions have been reported. We report a case of a 37-year-old man who suffered testicular trauma as a result of a less-lethal munition projectile. With the advent, and increased use, of less-lethal munitions by the military and law enforcement agencies, more of these new subsets of genitourinary trauma patients who will require care are sure to result.

  8. Paleoparasitology: the origin of human parasites

    OpenAIRE

    Adauto Araujo; Karl Reinhard; Luiz Fernando Ferreira; Elisa Pucu; Pedro Paulo Chieffi

    2013-01-01

    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 ph...

  9. Paleoparasitology: the origin of human parasites.

    Science.gov (United States)

    Araújo, Adauto; Reinhard, Karl; Ferreira, Luiz Fernando; Pucu, Elisa; Chieffi, Pedro Paulo

    2013-09-01

    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.

  10. 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.

  11. 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 parasit

  12. 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 parasit

  13. Social parasitism and the molecular basis of phenotypic evolution

    Directory of Open Access Journals (Sweden)

    Alessandro eCini

    2015-02-01

    Full Text Available Contrasting phenotypes arise from similar genomes through a combination of losses, gains, co-option and modifications of inherited genomic material. Understanding the molecular basis of this phenotypic diversity is a fundamental challenge in modern evolutionary biology. Comparisons of the genes and their expression patterns underlying traits in pairs of closely related species offer an unrivalled opportunity to evaluate the extent to which genomic material is reorganised to produce novel traits. Advances in molecular methods now allow us to dissect the molecular machinery underlying phenotypic diversity in almost any organism, from single-celled organisms to the most complex vertebrates. Here we discuss how comparisons of social parasites and their free-living hosts may provide unique insights into the molecular basis of phenotypic evolution. Social parasites evolve from a social ancestor and are specialised to exploit the socially acquired resources of their closely-related, free-living social host. Molecular comparisons of such species pairs can reveal how genomic material is re-organised in the loss of ancestral traits (i.e. of free-living traits in the parasites and the gain of new ones (i.e. specialist traits required for a parasitic lifestyle. We define hypotheses on the molecular basis of phenotypes in the evolution of social parasitism and discuss their wider application in understanding the molecular basis of phenotypic diversity within the theoretical framework of phenotypic plasticity and shifting reaction norms. Currently there are no data available to test these hypotheses, and so we also provide some proof of concept data for our conceptual model using the paper wasp social parasite-host system (Polistes sulcifer - Polistes dominula. This conceptual framework and first empirical data provide a spring-board for directing future genomic analyses on exploiting social parasites as a route to understanding the evolution of phenotypic

  14. Update on pathology of ocular parasitic disease

    OpenAIRE

    2016-01-01

    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 zoono...

  15. Blastocystis, an unrecognized parasite: an overview of pathogenesis and diagnosis

    Science.gov (United States)

    Wawrzyniak, Ivan; Poirier, Philippe; Viscogliosi, Eric; Dionigia, Meloni; Texier, Catherine; Delbac, Frédéric

    2013-01-01

    Blastocystis sp. is among the few enteric parasites with a prevalence that often exceeds 5% in the general population of industrialized countries and can reach 30–60% in developing countries. This parasite is frequently found in people who are immunocompromised (patients with human immunodeficiency virus/acquired immunodeficiency syndrome or cancer) and a higher risk of Blastocystis sp. infection has been found in people with close animal contact. Such prevalence in the human population and the zoonotic potential naturally raise questions about the impact of these parasites on public health and has increased interest in this area. Recent in vitro and in vivo studies have shed new light on the pathogenic power of this parasite, suggesting that Blastocystis sp. infection is associated with a variety of gastrointestinal disorders, may play a significant role in irritable bowel syndrome, and may be linked with cutaneous lesions (urticaria). Despite recent significant advances in the knowledge of the extensive genetic diversity of this species, the identification of extracellular proteases as virulence factors and the publication of one isolate genome, many aspects of the biology of Blastocystis sp. remain poorly investigated. In this review, we investigate several biological aspects of Blastocystis sp. (diversity and epidemiology, diagnosis tools and pathophysiology). These data pave the way for the following challenges concerning Blastocystis sp. research: deciphering key biological mechanisms and pathways of this parasite and clarification of its clinical impact in humans. PMID:25165551

  16. Blastocystis, an unrecognized parasite: an overview of pathogenesis and diagnosis.

    Science.gov (United States)

    Wawrzyniak, Ivan; Poirier, Philippe; Viscogliosi, Eric; Dionigia, Meloni; Texier, Catherine; Delbac, Frédéric; Alaoui, Hicham El

    2013-10-01

    Blastocystis sp. is among the few enteric parasites with a prevalence that often exceeds 5% in the general population of industrialized countries and can reach 30-60% in developing countries. This parasite is frequently found in people who are immunocompromised (patients with human immunodeficiency virus/acquired immunodeficiency syndrome or cancer) and a higher risk of Blastocystis sp. infection has been found in people with close animal contact. Such prevalence in the human population and the zoonotic potential naturally raise questions about the impact of these parasites on public health and has increased interest in this area. Recent in vitro and in vivo studies have shed new light on the pathogenic power of this parasite, suggesting that Blastocystis sp. infection is associated with a variety of gastrointestinal disorders, may play a significant role in irritable bowel syndrome, and may be linked with cutaneous lesions (urticaria). Despite recent significant advances in the knowledge of the extensive genetic diversity of this species, the identification of extracellular proteases as virulence factors and the publication of one isolate genome, many aspects of the biology of Blastocystis sp. remain poorly investigated. In this review, we investigate several biological aspects of Blastocystis sp. (diversity and epidemiology, diagnosis tools and pathophysiology). These data pave the way for the following challenges concerning Blastocystis sp. research: deciphering key biological mechanisms and pathways of this parasite and clarification of its clinical impact in humans.

  17. Parasites, pets, and people.

    Science.gov (United States)

    Marx, M B

    1991-03-01

    It is important for the family physician to understand that patients' relationships with their pets play an important role in helping maintain mental and physical health yet provide the potential for causing illness in the patient. Toxocara canis (dog roundworm) and Toxocara cati (cat roundworm) are the ascarids most commonly responsible for VLM and ocular larva migrans in humans. These roundworms live in their adult stage in the small intestine of the dog and cat where their eggs are passed in the feces. The eggs containing the infective larva are very sticky, thus an infant crawling around on the floor can easily pick these up on fingers that almost invariably end up in the mouth. Infections are usually mild and asymptomatic but with a persistent eosinophilia. Ocular larva migrans is the form usually occurring in older children and adults. Some public health veterinarians recommend that a puppy or kitten should not be obtained as a companion for a child who is not old enough to read, thus bypassing the crawling and toddler stages. Hookworm eggs, shed in the feces of infected dogs or cats, develop into the infective second stage within a week. Humans are usually infected when bare areas of skin such as bare feet or the torso come in contact with soil contaminated with the larvae. The second-stage larvae are able to penetrate the intact skin of humans and the foot pads of dogs and cats. In the United States, the common dog hookworm, A. caninum, is a widespread parasite. Human intestinal ancylostomiasis caused by this species is rare, with only six cases recorded in the literature. Infection in humans or animals by the common tapeworm of dogs and cats (Dipylidium caninum) requires ingestion of the intermediate host, the dog or cat flea containing the larva (cysticercoids) of the agent. Many cases in humans are asymptomatic. Dipylidiasis affects mainly infants and young children who may swallow a flea that hops up while the infant is crawling on the floor or fondling

  18. Yohimbine enhances protection of berberine against LPS-induced mouse lethality through multiple mechanisms.

    Directory of Open Access Journals (Sweden)

    Hui Li

    Full Text Available Sepsis remains a major cause of mortality in intensive care units, better therapies are urgently needed. Gram-negative bacterial lipopolysaccharide (LPS is an important trigger of sepsis. We have demonstrated that berberine (Ber protects against lethality induced by LPS, which is enhanced by yohimbine (Y pretreatment, and Ber combined with Y also improves survival in septic mice. However, the precise mechanisms by which Y enhances protection of Ber against LPS-induced lethality remain unclear. The present study confirmed that simultaneously administered Y also enhanced protection of Ber against LPS-induced lethality. Ber or/and Y attenuated liver injury, but not renal injury in LPS-challenged mice. Ber or/and Y all inhibited LPS-stimulated IκBα, JNK and ERK phosphorylation, NF-κB activation as well as TNF-α production. Ber also increased IL-10 production in LPS-challenged mice, which was enhanced by Y. Furthermore, Ber or/and Y all suppressed LPS-induced IRF3, TyK2 and STAT1 phosphorylation, as well as IFN-β and IP-10 mRNA expression in spleen of mice at 1 h after LPS challenge. Especially, Y enhanced the inhibitory effect of Ber on LPS-induced IP-10 mRNA expression. In vitro experiments further demonstrated that Y significantly enhanced the inhibitory effect of Ber on TNF-α production in LPS-treated peritoneal macrophages, Ber combined with Y promoted LPS-induced IL-10 production and LPS-stimulated IκBα, JNK, ERK and IRF3 phosphorylation and NF-κB activation were also suppressed by Ber or/and Y pretreatment in peritoneal macrophages. Taken together, these results demonstrate that Y enhances the protection of Ber against LPS-induced lethality in mice via attenuating liver injury, upregulating IL-10 production and suppressing IκBα, JNK, ERK and IRF3 phosphorylation. Ber combined with Y may be an effective immunomodulator agent for the prevention of sepsis.

  19. Social Behaviours and Networks of Vervet Monkeys Are Influenced by Gastrointestinal Parasites

    Science.gov (United States)

    Friant, Sagan; Godfrey, Kathleen; Liu, Cynthia; Sakar, Dipto; Schoof, Valérie A. M.; Sengupta, Raja; Twinomugisha, Dennis; Valenta, Kim; Goldberg, Tony L.

    2016-01-01

    Substantial research has shown that while some parasite infections can be fatal to hosts, most infections are sub-clinical and non-lethal. Such sub-clinical infections can nonetheless have negative consequences for the long-term fitness of the host such as reducing juvenile growth and the host’s ability to compete for food and mates. With such effects, infected individuals are expected to exhibit behavioural changes. Here we use a parasite removal experiment to quantify how gastrointestinal parasite infections affect the behaviour of vervet monkeys (Chlorocebus aethiops) at Lake Nabugabo, Uganda. Behavioural profiles and the structure of nearest neighbour relationships varied significantly. As predicted, after deworming the duration of the resting events decreased, which is consistent with the idea that parasite infections are energetically costly. In contrast to what was predicted, we could not reject the null hypothesis and we observed no change in either the frequency or duration of grooming, but we found that the duration of travel events increased. A network analysis revealed that after deworming, individuals tended to have more nearest neighbours and hence probably more frequent interactions, with this effect being particularly marked for juveniles. The heightened response by juveniles may indicate that they are avoiding infected individuals more than other age classes because it is too costly to move energy away from growth. We consider that populations with high parasite burden may have difficulties developing social networks and behaviours that could have cascading effects that impact the population in general. PMID:27580121

  20. Protein palmitoylation in protozoan parasites.

    Science.gov (United States)

    Corvi, Maria Martha; Berthiaume, Luc Gerard; De Napoli, Maximiliano Gabriel

    2011-06-01

    Palmitoylation plays an important role in the regulation of the localization and function of the modified protein. Although many aspects of protein palmitoylation have been identified in mammalian and yeast cells, little information is available of this modification in protozoan parasites. Protein palmitoylation has been described for a few set of proteins in E.tenella, P. falciparum, T. gondii, G. lamblia and T. cruzi. Interestingly, in all these parasites palmitoylated proteins appears to be involved in vital processes such as invasion and motility. In addition, most of these parasites contain in their genomes genes that encode for putative palmitoyl-acyl transferases, the enzymes catalyzing the palmitoylation reaction. Although protein palmitoylation could be playing key roles in invasion and motility in a variety of parasites, little is known about this important reversible modification of proteins that typically plays a role in membrane tethering. As such, this review will focus on the main features of protein palmitoylation as well as provide an overview of the state of knowledge of this modification in protozoan parasites.

  1. Erythropoiesis suppression is associated with anthrax lethal toxin-mediated pathogenic progression.

    Directory of Open Access Journals (Sweden)

    Hsin-Hou Chang

    Full Text Available Anthrax is a disease caused by the bacterium Bacillus anthracis, which results in high mortality in animals and humans. Although some of the mechanisms are already known such as asphyxia, extensive knowledge of molecular pathogenesis of this disease is deficient and remains to be further investigated. Lethal toxin (LT is a major virulence factor of B. anthracis and a specific inhibitor/protease of mitogen-activated protein kinase kinases (MAPKKs. Anthrax LT causes lethality and induces certain anthrax-like symptoms, such as anemia and hypoxia, in experimental mice. Mitogen-activated protein kinases (MAPKs are the downstream pathways of MAPKKs, and are important for erythropoiesis. This prompted us to hypothesize that anemia and hypoxia may in part be exacerbated by erythropoietic dysfunction. As revealed by colony-forming cell assays in this study, LT challenges significantly reduced mouse erythroid progenitor cells. In addition, in a proteolytic activity-dependent manner, LT suppressed cell survival and differentiation of cord blood CD34(+-derived erythroblasts in vitro. Suppression of cell numbers and the percentage of erythroblasts in the bone marrow were detected in LT-challenged C57BL/6J mice. In contrast, erythropoiesis was provoked through treatments of erythropoietin, significantly ameliorating the anemia and reducing the mortality of LT-treated mice. These data suggested that suppressed erythropoiesis is part of the pathophysiology of LT-mediated intoxication. Because specific treatments to overcome LT-mediated pathogenesis are still lacking, these efforts may help the development of effective treatments against anthrax.

  2. Protection of Mice from Lethal Endotoxemia by Chimeric Human BPI-Fcγ1 Gene Delivery

    Institute of Scientific and Technical Information of China (English)

    Chen Li; Jing Li; Zhe Lv; Xinghua Guo; Qinghua Chen; Qingli Kong; Yunqing An

    2006-01-01

    To evaluate the potentiality of applying gene therapy to endotoxemia in high-risk patients, we investigated the effects of transferring an adeno-associated virus serotype 2 (AAV2)-mediated BPI-Fcγ1 gene on protecting mice from challenge of lethal endotoxin. The chimeric BPI-Fcγ1 gene consists of two parts, one encods functional N-terminus (1 to 199 amino acidic residues) of human BPI, which is a bactericidal/permeability-increasing protein,and the other encodes Fc segment of human immunoglobulin G1 (Fcγ1). Our results indicated that the target protein could be expressed and secreted into the serum of the gene-transferred mice. After lethal endotoxin challenge, the levels of endotoxin and TNF-α in the gene-transferred mice were decreased. The survival rate of the BPI-Fcγ1 gene-transferred mice was markedly increased. Our data suggest that AAV2-mediated chimeric BPI-Fcγ1 gene delivery can potentially be used clinically for the protection and treatment of endotoxemia and endotoxic shock in high-risk individuals.

  3. Experimental Protection of Diabetic Mice against Lethal P. aeruginosa Infection by Bacteriophage

    Directory of Open Access Journals (Sweden)

    Nagaveni Shivshetty

    2014-01-01

    Full Text Available The emergence of antibiotic-resistant bacterial strains has become a global crisis and is vulnerable for the exploration of alternative antibacterial therapies. The present study emphasizes the use of bacteriophage for the treatment of multidrug resistant P. aeruginosa. P. aeruginosa was used to induce septicemia in streptozotocin (STZ induced diabetic and nondiabetic mice by intraperitoneal (i.p. injection of 3 × 108 CFU, resulting in a fatal bacteremia within 48 hrs. A single i.p. injection of 3 × 109 PFU phage GNCP showed efficient protection in both diabetic (90% and nondiabetic (100% bacteremic mice. It was further noted that the protection rate was reduced in diabetic mice when phage GNCP was administered after 4 h and 6 h of lethal bacterial challenge. In contrast, nondiabetic bacteremic mice were rescued even when treatment was delayed up to 20 h after lethal bacterial challenge. Evaluation of results confirmed that a single intraperitoneal injection of the phage dose (3 × 109 PFU/mL was more effective than the multiple doses of imipenem. These results uphold the efficacy of phage therapy against pernicious P. aeruginosa infections, especially in cases of immunocompromised host.

  4. Host-parasite interactions: Marine bivalve molluscs and protozoan parasites, Perkinsus species.

    Science.gov (United States)

    Soudant, Philippe; E Chu, Fu-Lin; Volety, Aswani

    2013-10-01

    This review assesses and examines the work conducted to date concerning host and parasite interactions between marine bivalve molluscs and protozoan parasites, belonging to Perkinsus species. The review focuses on two well-studied host-parasite interaction models: the two clam species, Ruditapes philippinarum and R. decussatus, and the parasite Perkinsus olseni, and the eastern oyster, Crassostrea virginica, and the parasite Perkinsus marinus. Cellular and humoral defense responses of the host in combating parasitic infection, the mechanisms (e.g., antioxidant enzymes, extracellular products) employed by the parasite in evading host defenses as well as the role of environmental factors in modulating the host-parasite interactions are described.

  5. Comparative toxicity and efficacy of engineered anthrax lethal toxin variants with broad anti-tumor activities

    Energy Technology Data Exchange (ETDEWEB)

    Peters, Diane E. [Proteases and Tissue Remodeling Section, Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD (United States); Program of Pharmacology and Experimental Therapeutics, Tufts University School of Medicine, Boston, MA (United States); Hoover, Benjamin [Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD (United States); Cloud, Loretta Grey [Proteases and Tissue Remodeling Section, Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD (United States); Liu, Shihui [Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD (United States); Molinolo, Alfredo A. [Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD (United States); Leppla, Stephen H. [Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD (United States); Bugge, Thomas H., E-mail: thomas.bugge@nih.go [Proteases and Tissue Remodeling Section, Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD (United States)

    2014-09-01

    We have previously designed and characterized versions of anthrax lethal toxin that are selectively cytotoxic in the tumor microenvironment and which display broad and potent anti-tumor activities in vivo. Here, we have performed the first direct comparison of the safety and efficacy of three engineered anthrax lethal toxin variants requiring activation by either matrix-metalloproteinases (MMPs), urokinase plasminogen activator (uPA) or co-localized MMP/uPA activities. C57BL/6J mice were challenged with six doses of engineered toxins via intraperitoneal (I.P.) or intravenous (I.V.) dose routes to determine the maximum tolerated dose for six administrations (MTD6) and dose-limiting toxicities. Efficacy was evaluated using the B16-BL6 syngraft model of melanoma; mice bearing established tumors were treated with six I.P. doses of toxin and tumor measurements and immunohistochemistry, paired with terminal blood work, were used to elaborate upon the anti-tumor mechanism and relative efficacy of each variant. We found that MMP-, uPA- and dual MMP/uPA-activated anthrax lethal toxins exhibited the same dose-limiting toxicity; dose-dependent GI toxicity. In terms of efficacy, all three toxins significantly reduced primary B16-BL6 tumor burden, ranging from 32% to 87% reduction, and they also delayed disease progression as evidenced by dose-dependent normalization of blood work values. While target organ toxicity and effective doses were similar amongst the variants, the dual MMP/uPA-activated anthrax lethal toxin exhibited the highest I.P. MTD6 and was 1.5–3-fold better tolerated than the single MMP- and uPA-activated toxins. Overall, we demonstrate that this dual MMP/uPA-activated anthrax lethal toxin can be administered safely and is highly effective in a preclinical model of melanoma. This modified bacterial cytotoxin is thus a promising candidate for further clinical development and evaluation for use in treating human cancers. - Highlights: • Toxicity and anti

  6. Taming Parasites by Tailoring Them

    Directory of Open Access Journals (Sweden)

    Bingjian Ren

    2017-07-01

    Full Text Available The next-generation gene editing based on CRISPR (clustered regularly interspaced short palindromic repeats has been successfully implemented in a wide range of organisms including some protozoan parasites. However, application of such a versatile game-changing technology in molecular parasitology remains fairly underexplored. Here, we briefly introduce state-of-the-art in human and mouse research and usher new directions to drive the parasitology research in the years to come. In precise, we outline contemporary ways to embolden existing apicomplexan and kinetoplastid parasite models by commissioning front-line gene-tailoring methods, and illustrate how we can break the enduring gridlock of gene manipulation in non-model parasitic protists to tackle intriguing questions that remain long unresolved otherwise. We show how a judicious solicitation of the CRISPR technology can eventually balance out the two facets of pathogen-host interplay.

  7. Parasitic diseases of the pleura.

    Science.gov (United States)

    Lal, Chitra; Huggins, John Terrill; Sahn, Steven A

    2013-05-01

    Parasitic infections are prevalent in certain parts of the world and may cause pleural involvement, which often goes unrecognized. Common parasites involving the pleura include Entamoeba histolytica, Echinococcus granulosus and Paragonimus westermani. Amebiasis can cause empyema with "anchovy sauce" pus, reactive pleural effusions and bronchopleural fistula with hydropneumothorax. Echinococcosis may result in pleural thickening, pneumothorax, secondary pleural hydatidosis and pleural effusions. Paragonimiasis may cause chylous and cholesterol pleural effusions, pleural thickening and pneumothorax. Less commonly, pulmonary eosinophilia, or Loeffler's syndrome, caused by Ascaris lumbricoides, Ancylostoma duodenale and Necator americanus and tropical pulmonary eosinophilia caused by Wuchereria bancrofti and Brugia malayi may involve the pleura. This article provides a comprehensive review of parasitic infections involving the pleura. A high index of suspicion in the appropriate clinical setting is required to facilitate prompt diagnosis and treatment of these diseases.

  8. A multivariate model of stakeholder preference for lethal cat management.

    Science.gov (United States)

    Wald, Dara M; Jacobson, Susan K

    2014-01-01

    Identifying stakeholder beliefs and attitudes is critical for resolving management conflicts. Debate over outdoor cat management is often described as a conflict between two groups, environmental advocates and animal welfare advocates, but little is known about the variables predicting differences among these critical stakeholder groups. We administered a mail survey to randomly selected stakeholders representing both of these groups (n=1,596) in Florida, where contention over the management of outdoor cats has been widespread. We used a structural equation model to evaluate stakeholder intention to support non-lethal management. The cognitive hierarchy model predicted that values influenced beliefs, which predicted general and specific attitudes, which in turn, influenced behavioral intentions. We posited that specific attitudes would mediate the effect of general attitudes, beliefs, and values on management support. Model fit statistics suggested that the final model fit the data well (CFI=0.94, RMSEA=0.062). The final model explained 74% of the variance in management support, and positive attitudes toward lethal management (humaneness) had the largest direct effect on management support. Specific attitudes toward lethal management and general attitudes toward outdoor cats mediated the relationship between positive (pstakeholder intention to support non-lethal cat management. Our findings suggest that stakeholders can simultaneously perceive both positive and negative beliefs about outdoor cats, which influence attitudes toward and support for non-lethal management.

  9. Emerging Functions of Transcription Factors in Malaria Parasite

    Directory of Open Access Journals (Sweden)

    Renu Tuteja

    2011-01-01

    Full Text Available Transcription is a process by which the genetic information stored in DNA is converted into mRNA by enzymes known as RNA polymerase. Bacteria use only one RNA polymerase to transcribe all of its genes while eukaryotes contain three RNA polymerases to transcribe the variety of eukaryotic genes. RNA polymerase also requires other factors/proteins to produce the transcript. These factors generally termed as transcription factors (TFs are either associated directly with RNA polymerase or add in building the actual transcription apparatus. TFs are the most common tools that our cells use to control gene expression. Plasmodium falciparum is responsible for causing the most lethal form of malaria in humans. It shows most of its characteristics common to eukaryotic transcription but it is assumed that mechanisms of transcriptional control in P. falciparum somehow differ from those of other eukaryotes. In this article we describe the studies on the main TFs such as myb protein, high mobility group protein and ApiA2 family proteins from malaria parasite. These studies show that these TFs are slowly emerging to have defined roles in the regulation of gene expression in the parasite.

  10. Interplay between fungicides and parasites: Tebuconazole, but not copper, suppresses infection in a Daphnia-Metschnikowia experimental model.

    Science.gov (United States)

    Cuco, Ana P; Abrantes, Nelson; Gonçalves, Fernando; Wolinska, Justyna; Castro, Bruno B

    2017-01-01

    Natural populations are commonly exposed to complex stress scenarios, including anthropogenic contamination and their biological enemies (e.g., parasites). The study of the pollutant-parasite interplay is especially important, given the need for adequate regulations to promote improved ecosystem protection. In this study, a host-parasite model system (Daphnia spp. and the microparasitic yeast Metschnikowia bicuspidata) was used to explore the reciprocal effects of contamination by common agrochemical fungicides (copper sulphate and tebuconazole) and parasite challenge. We conducted 21-day life history experiments with two host clones exposed to copper (0.00, 25.0, 28.8 and 33.1 μg L-1) or tebuconazole (0.00, 154, 192 and 240 μg L-1), in the absence or presence of the parasite. For each contaminant, the experimental design consisted of 2 Daphnia clones × 4 contaminant concentrations × 2 parasite treatments × 20 replicates = 320 experimental units. Copper and tebuconazole decreased Daphnia survival or reproduction, respectively, whilst the parasite strongly reduced host survival. Most importantly, while copper and parasite effects were mostly independent, tebuconazole suppressed infection. In a follow-up experiment, we tested the effect of a lower range of tebuconazole concentrations (0.00, 6.25, 12.5, 25.0, 50.0 and 100 μg L-1) crossed with increasing parasite challenge (2 Daphnia clones × 6 contaminant concentrations × 2 parasite levels × 20 replicates = 480 experimental units). Suppression of infection was confirmed at environmentally relevant concentrations (> 6.25 μg L-1), irrespective of the numbers of parasite challenge. The ecological consequences of such a suppression of infection include interferences in host population dynamics and diversity, as well as community structure and energy flow across the food web, which could upscale to ecosystem level given the important role of parasites.

  11. Interplay between fungicides and parasites: Tebuconazole, but not copper, suppresses infection in a Daphnia-Metschnikowia experimental model

    Science.gov (United States)

    Cuco, Ana P.; Abrantes, Nelson; Gonçalves, Fernando; Wolinska, Justyna

    2017-01-01

    Natural populations are commonly exposed to complex stress scenarios, including anthropogenic contamination and their biological enemies (e.g., parasites). The study of the pollutant-parasite interplay is especially important, given the need for adequate regulations to promote improved ecosystem protection. In this study, a host-parasite model system (Daphnia spp. and the microparasitic yeast Metschnikowia bicuspidata) was used to explore the reciprocal effects of contamination by common agrochemical fungicides (copper sulphate and tebuconazole) and parasite challenge. We conducted 21-day life history experiments with two host clones exposed to copper (0.00, 25.0, 28.8 and 33.1 μg L-1) or tebuconazole (0.00, 154, 192 and 240 μg L-1), in the absence or presence of the parasite. For each contaminant, the experimental design consisted of 2 Daphnia clones × 4 contaminant concentrations × 2 parasite treatments × 20 replicates = 320 experimental units. Copper and tebuconazole decreased Daphnia survival or reproduction, respectively, whilst the parasite strongly reduced host survival. Most importantly, while copper and parasite effects were mostly independent, tebuconazole suppressed infection. In a follow-up experiment, we tested the effect of a lower range of tebuconazole concentrations (0.00, 6.25, 12.5, 25.0, 50.0 and 100 μg L-1) crossed with increasing parasite challenge (2 Daphnia clones × 6 contaminant concentrations × 2 parasite levels × 20 replicates = 480 experimental units). Suppression of infection was confirmed at environmentally relevant concentrations (> 6.25 μg L-1), irrespective of the numbers of parasite challenge. The ecological consequences of such a suppression of infection include interferences in host population dynamics and diversity, as well as community structure and energy flow across the food web, which could upscale to ecosystem level given the important role of parasites. PMID:28231278

  12. 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.

  13. Canine and feline parasitic zoonoses in China.

    Science.gov (United States)

    Chen, Jia; Xu, Min-Jun; Zhou, Dong-Hui; Song, Hui-Qun; Wang, Chun-Ren; Zhu, Xing-Quan

    2012-07-28

    Canine and feline parasitic zoonoses have not been given high priority in China, although the role of companion animals as reservoirs for zoonotic parasitic diseases has been recognized worldwide. With an increasing number of dogs and cats under unregulated conditions in China, the canine and feline parasitic zoonoses are showing a trend towards being gradually uncontrolled. Currently, canine and feline parasitic zoonoses threaten human health, and cause death and serious diseases in China. This article comprehensively reviews the current status of major canine and feline parasitic zoonoses in mainland China, discusses the risks dogs and cats pose with regard to zoonotic transmission of canine and feline parasites, and proposes control strategies and measures.

  14. The Geological Record of Parasitic Nematode Evolution.

    Science.gov (United States)

    Poinar, George O

    2015-01-01

    This chapter discusses the evolutionary history of nematode parasites of invertebrates, vertebrates and plants based on fossil remains in amber, stone and coprolites dating from the Palaeozoic to the Holocene. The earliest parasitic nematode is a primitive plant parasite from the Devonian. Fossil invertebrate-parasitic nematodes first appeared in the Early Cretaceous, while the earliest fossil vertebrate-parasitic nematodes are from Upper Triassic coprolites. Specific examples of fossil nematode parasites over time are presented, along with views on the origin and evolution of nematodes and their hosts. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Parasites, emerging disease and wildlife conservation.

    Science.gov (United States)

    Thompson, R C A; Lymbery, A J; Smith, A

    2010-08-15

    In this review some emerging issues of parasite infections in wildlife, particularly in Australia, are considered. We discuss the importance of understanding parasite biodiversity in wildlife in terms of conservation, the role of wildlife as reservoirs of parasite infection, and the role of parasites within the broader context of the ecosystem. Using a number of parasite species, the value of undertaking longitudinal surveillance in natural systems using non-invasive sampling and molecular tools to characterise infectious agents is illustrated in terms of wildlife health, parasite biodiversity and ecology.

  16. Enhancement of Hsp70 synthesis protects common carp, Cyprinus carpio L., against lethal ammonia toxicity.

    Science.gov (United States)

    Sung, Y Y; Roberts, R J; Bossier, P

    2012-08-01

    Exposure to TEX-OE®, a patented extract of the prickly pear cactus (Opuntia ficus indica) containing chaperone-stimulating factor, was shown to protect common carp, Cyprinus carpio L., fingerlings against acute ammonia stress. Survival was enhanced twofold from 50% to 95% after exposure to 5.92 mg L(-1) NH(3) , a level determined in the ammonia challenge bioassay as the 1-h LD50 concentration for this species. Survival of TEX-OE®-pre-exposed fish was enhanced by 20% over non-exposed controls during lethal ammonia challenge (14.21 mg L(-1)  NH(3) ). Increase in the levels of gill and muscle Hsp70 was evident in TEX-OE®-pre-exposed fish but not in the unexposed controls, indicating that application of TEX-OE® accelerated carp endogenous Hsp70 synthesis during ammonia perturbation. Protection against ammonia was correlated with Hsp70 accretion.

  17. "Rickettsia amblyommii" induces cross protection against lethal Rocky Mountain spotted fever in a guinea pig model.

    Science.gov (United States)

    Blanton, Lucas S; Mendell, Nicole L; Walker, David H; Bouyer, Donald H

    2014-08-01

    Rocky Mountain spotted fever (RMSF) is a severe illness caused by Rickettsia rickettsii for which there is no available vaccine. We hypothesize that exposure to the highly prevalent, relatively nonpathogenic "Rickettsia amblyommii" protects against R. rickettsii challenge. To test this hypothesis, guinea pigs were inoculated with "R. amblyommii." After inoculation, the animals showed no signs of illness. When later challenged with lethal doses of R. rickettsii, those previously exposed to "R. amblyommii" remained well, whereas unimmunized controls developed severe illness and died. We conclude that "R. amblyommii" induces an immune response that protects from illness and death in the guinea pig model of RMSF. These results provide a basis for exploring the use of low-virulence rickettsiae as a platform to develop live attenuated vaccine candidates to prevent severe rickettsioses.

  18. Oncogenic Brain Metazoan Parasite Infection

    Directory of Open Access Journals (Sweden)

    Angela N. Spurgeon

    2013-01-01

    Full Text Available Multiple observations suggest that certain parasitic infections can be oncogenic. Among these, neurocysticercosis is associated with increased risk for gliomas and hematologic malignancies. We report the case of a 71-year-old woman with colocalization of a metazoan parasite, possibly cysticercosis, and a WHO grade IV neuroepithelial tumor with exclusively neuronal differentiation by immunohistochemical stains (immunopositive for synaptophysin, neurofilament protein, and Neu-N and not for GFAP, vimentin, or S100. The colocalization and temporal relationship of these two entities suggest a causal relationship.

  19. Crossover suppressors and balanced recessive lethals in Caenorhabditis elegans. [Nematode

    Energy Technology Data Exchange (ETDEWEB)

    Herman, R.K.

    1978-01-01

    Two dominant suppressors of crossing over have been identified following x-ray treatment of the small nematode C. elegans. They suppress crossing over in linkage group II (LGII) about 100-fold and 50-fold and are both tightly linked to LGII markers. One, called C1, segregates independently of all other linkage groups and is homozygous fertile. The other is a translocation involving LGII and X. The translocation also suppresses crossing over along the right half of X and is homozygous lethal. C1 has been used as a balancer of LGII recessive lethal and sterile mutations induced by EMS. The frequencies of occurrence of lethals and steriles were approximately equal. Fourteen mutations were assigned to complementation groups and mapped. They tended to map in the same region where LGII visibles are clustered.

  20. Lethal effects of short-wavelength visible light on insects.

    Science.gov (United States)

    Hori, Masatoshi; Shibuya, Kazuki; Sato, Mitsunari; Saito, Yoshino

    2014-12-09

    We investigated the lethal effects of visible light on insects by using light-emitting diodes (LEDs). The toxic effects of ultraviolet (UV) light, particularly shortwave (i.e., UVB and UVC) light, on organisms are well known. However, the effects of irradiation with visible light remain unclear, although shorter wavelengths are known to be more lethal. Irradiation with visible light is not thought to cause mortality in complex animals including insects. Here, however, we found that irradiation with short-wavelength visible (blue) light killed eggs, larvae, pupae, and adults of Drosophila melanogaster. Blue light was also lethal to mosquitoes and flour beetles, but the effective wavelength at which mortality occurred differed among the insect species. Our findings suggest that highly toxic wavelengths of visible light are species-specific in insects, and that shorter wavelengths are not always more toxic. For some animals, such as insects, blue light is more harmful than UV light.

  1. Impact of acute alcohol consumption on lethality of suicide methods.

    Science.gov (United States)

    Park, C Hyung Keun; Yoo, Seong Ho; Lee, Jaewon; Cho, Sung Joon; Shin, Min-Sup; Kim, Eun Young; Kim, Se Hyun; Ham, Keunsoo; Ahn, Yong Min

    2017-05-01

    The influence of acute alcohol consumption on the factors related to suicide remains understudied. Thus, the present study investigated the relationship between blood alcohol content (BAC) and the lethality of suicide methods. Autopsy data on 315 South Korean suicide completers with a positive BAC were collected from a nationwide pool between May 2015 and November 2015, and the methods were dichotomised as suicide methods of low lethality (SMLL; drug/chemical overdose and sharp objects, n=67) and suicide methods of high lethality (SMHL; everything else, n=243). BAC at the time of autopsy and various suicide-related factors of these two groups were compared with logistic regression analyses. Compared to suicide completers with a BAC in the lowest range of 0.011-0.049%, suicide completers with a BAC in the range of 0.150-0.199% were more likely to use SMHL (odds ratio [OR]: 3.644, 95% confidence interval [CI]: 1.221-10.874). Additionally, the adoption of SMHL was significantly associated with the absence of a psychiatric illness (OR: 0.433, 95% CI: 0.222-0.843) and a younger age; the OR for high BAC among subjects in their 40s was 0.266 (95% CI: 0.083-0.856); in their 50s, 0.183 (95% CI: 0.055-0.615); and in their 60s, 0.057 (95% CI: 0.015-0.216). The relationship between BAC and suicide method lethality was represented by a bell-shaped pattern in which suicide methods of high lethality were more likely to be used by suicide completers with mid-range BAC levels. The increased impulsivity and impairments in particular executive functions, including planning and organization, associated with acute alcohol use may influence the selection of a particular suicide method based on its lethality. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Efficacy of 11 Brazilian essential oils on lethality of the cattle tick Rhipicephalus (Boophilus) microplus.

    Science.gov (United States)

    Chagas, Ana Carolina de Souza; Oliveira, Márcia Cristina de Sena; Giglioti, Rodrigo; Santana, Raul Costa Mascarenhas; Bizzo, Humberto Ribeiro; Gama, Paola Ervatti; Chaves, Francisco Celio Maia

    2016-04-01

    Herbal extracts have been investigated as an alternative for parasite control, aiming to slow the development of resistance and to obtain low-cost biodegradable parasiticides. The goal of this study was to evaluate the efficacy, in vitro, of 11 essential oils from Brazil on reproductive efficiency and lethality of the cattle tick Rhipicephalus (Boophilus) microplus. The effects of oils extracted from Curcuma longa, Zingiber officinale, Lippia alba, Lippia gracilis, Lippia origanoides, Lippia sidoides, Mentha arvensis, Mentha piperita, Croton cajucara (white and red), and Croton sacaquinha on ticks were investigated by the Immersion Test with Engorged Females (ITEF) and the modified Larval Packet Test (LPT). Distilled water and 2% Tween 80 were used as control treatments. Chemical analysis of the oils was done with gas chromatography coupled with mass spectrometry. Analysis of the in vitro tests using Probit (SAS program) allowed the calculation of lethal concentrations (LCs). Lower reproductive efficiency indexes and higher efficacy percentages in the ITEF were obtained with the oils extracted from C. longa (24 and 71%, respectively) and M. arvensis oils (27 and 73%, respectively). Lower LC50 was reached with C. longa (10.24 mg/mL), L. alba (10.78 mg/mL), M. arvensis (22.31 mg/mL), L. sidoides (27.67 mg/mL), and C. sacaquinha (29.88 mg/mL) oils. In the LPT, species from Zingiberaceae and Verbenaceae families caused 100% lethality at 25 mg/mL, except for L. sidoides. The most effective oils were from C. longa, L. gracilis, L. origanoides, L. alba, and Z. officinale. The LC50 and LC90 were, respectively: 0.54 and 1.80 mg/mL, 3.21 and 7.03 mg/mL, 3.10 and 8.44 mg/mL, 5.85 and 11.14 mg/mL, and 7.75 and 13.62 mg/mL. The efficacy was directly related to the major components in each essential oil, and the oils derived from Croton genus presented the worst performance, suggesting the absence of synergistic effect among its compounds. Since C. longa, containing 62

  3. Born in an alien nest: how do social parasite male offspring escape from host aggression?

    Directory of Open Access Journals (Sweden)

    Patrick Lhomme

    Full Text Available Social parasites exploit the colony resources of social insects. Some of them exploit the host colony as a food resource or as a shelter whereas other species also exploit the brood care behavior of their social host. Some of these species have even lost the worker caste and rely completely on the host's worker force to rear their offspring. To avoid host defenses and bypass their recognition code, these social parasites have developed several sophisticated chemical infiltration strategies. These infiltration strategies have been highly studied in several hymenopterans. Once a social parasite has successfully entered a host nest and integrated its social system, its emerging offspring still face the same challenge of avoiding host recognition. However, the strategy used by the offspring to survive within the host nest without being killed is still poorly documented. In cuckoo bumblebees, the parasite males completely lack the morphological and chemical adaptations to social parasitism that the females possess. Moreover, young parasite males exhibit an early production of species-specific cephalic secretions, used as sexual pheromones. Host workers might thus be able to recognize them. Here we used a bumblebee host-social parasite system to test the hypothesis that social parasite male offspring exhibit a chemical defense strategy to escape from host aggression during their intranidal life. Using behavioral assays, we showed that extracts from the heads of young cuckoo bumblebee males contain a repellent odor that prevents parasite males from being attacked by host workers. We also show that social parasitism reduces host worker aggressiveness and helps parasite offspring acceptance.

  4. 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...... extract showed potent inhibition of A. suum larval migration (EC50 value of 42 μg/ml) and was also active against larval and adult stages of O. dentatum. Electron microscopy demonstrated significant structural damage to the cuticle and digestive tissues in nematodes exposed to PSM. Plants rich in PSM...

  5. A De Novo-Assembly Based Data Analysis Pipeline for Plant Obligate Parasite Metatranscriptomic Studies

    OpenAIRE

    Li Guo; Kelly S Allen; Greg A Deiulio; Yong Zhang; Madeiras, Angela M.; Robert L Wick; Li-Jun Ma

    2016-01-01

    Current and emerging plant diseases caused by obligate parasitic microbes such as rusts, downy mildews, and powdery mildews threaten worldwide crop production and food safety. These obligate parasites are typically unculturable in the laboratory, posing technical challenges to characterize them at the genetic and genomic level. Here we have developed a data analysis pipeline integrating several bioinformatic software programs. This pipeline facilitates rapid gene discovery and expression anal...

  6. Prenatal diagnosis of lethal osteogenesis imperfecta in twin pregnancy.

    Science.gov (United States)

    Morin, L R; Herlicoviez, M; Loisel, J C; Jacob, B; Feuilly, C; Stanescu, V

    1991-06-01

    Lethal osteogenesis imperfecta was diagnosed at 27 weeks amenorrea in one fetus of a bichorial twin pregnancy. Sonographic findings included: short-limb dwarfism, hypotrophy and hypoechoic bones. The affected fetus was so translucent that only the normal fetus could be seen on plain in utero radiography. The affected fetus died immediately after birth. Postmortem radiography and histology were typical of lethal osteogenesis imperfecta of type IIA. Aids to the etiological diagnosis of in utero dwarfism are presented. Sonographic features correlated with neonatal death are described.

  7. Immediate and lag effects of pesticide exposure on parasite resistance in larval amphibians.

    Science.gov (United States)

    Pochini, Katherine M; Hoverman, Jason T

    2017-01-11

    Across host-parasite systems, there is evidence that pesticide exposure increases parasite loads and mortality following infection. However, whether these effects are driven by reductions in host resistance to infection or slower rates of parasite clearance is often unclear. Using controlled laboratory experiments, we examined the ability of larval northern leopard frogs (Lithobates pipiens) and American toads (Anaxyrus americanus) to resist and clear trematode (Echinoparyphium sp.) infections following exposure to the insecticide carbaryl. Northern leopard frogs exposed to 1 mg L-1 of carbaryl had 61% higher parasite loads compared with unexposed individuals, while there was no immediate effect of carbaryl on parasite encystment in American toads. However, when tadpoles were exposed to carbaryl and moved to freshwater for 14 days before the parasite challenge, we recovered 37 and 63% more parasites from carbaryl-exposed northern leopard frogs and American toads, respectively, compared with the control. No effects on clearance were found for either species. Collectively, our results suggest that pesticide exposure can reduce the ability of amphibians to resist parasite infections and that these effects can persist weeks following exposure. It is critical for researchers to incorporate species interactions into toxicity studies to improve our understanding of how contaminants affect ecological communities.

  8. Lethal and Sublethal Effects of Insecticides Used on Citrus, on the Ectoparasitoid Tamarixia radiata.

    Science.gov (United States)

    Beloti, Vitor Hugo; Alves, Gustavo Rodrigues; Araújo, Diogo Feliciano Dias; Picoli, Mateus Manara; Moral, Rafael de Andrade; Demétrio, Clarice Garcia Borges; Yamamoto, Pedro Takao

    2015-01-01

    Huanglongbing (HLB) is a disease associated with the bacteria "Candidatus Liberibacter spp." and has been devastating citrus orchards around the world. Its management involves control of the insect vector, the Asian citrus psyllid Diaphorina citri Kuwayama. However, the indiscriminate use of chemicals has caused pest outbreaks and eliminated the natural enemies of the vector, such as the parasitoid Tamarixia radiata (Waterston), the main agent for biological control of D. citri. This study assessed the lethal and sublethal effects of insecticides recommended for integrated production of citrus on the parasitoid T. radiata. When adult parasitoids were exposed to residues of 25 insecticides, 20% of them, i.e., gamma-cyhalothrin, etofenprox, azadirachtin, tebufenozide and pyriproxyfen, were considered as harmless (Class 1), 12% as slightly harmful (Class 2), 12% as moderately harmful (Class 3) and 56% as harmful (Class 4), according to the classification proposed by the IOBC/WPRS. Afterward, 14 insecticides (5 harmless and 9 harmful) were sprayed on the parasitoid pupae. Of the 14 insecticides tested, only the organophosphates dimethoate and chlorpyrifos affected the parasitoid emergence. The effects of insecticides on the parasitism capacity of adults exposed to residues of azadirachtin, etofenprox, gamma-cyhalothrin, pyriproxyfen and tebufenozide (harmless) were also evaluated. Tebufenozide and gamma-cyhalothrin affected the parasitism of the F0 generation, but did not affect the emergence of the F1 and F2 generations. Therefore, for an effective IPM program, selective insecticides or harmful pesticides to adult parasitoids could be used in the field, provided that the adults do not occur naturally and the chemical applications do not coincide with parasitoid releases.

  9. Sacral Rachipagus Parasite: A Case Report.

    Science.gov (United States)

    Rattan, Kamal Nain; Singh, Jasbir; Dalal, Poonam; Sonika, Pallavi; Rattan, Ananta

    2016-01-01

    We are reporting a case of sacral rachipagus parasite which was vaginally delivered as a large irregular mass attached to the sacral region by a vascular pedicle. This case was managed successfully by surgical excision of parasite.

  10. O&P (Ova and Parasite) Test

    Science.gov (United States)

    ... Was this page helpful? Also known as: O&P Formal name: Parasitic Examination, stool Related tests: Gastrointestinal ... is it used? The ova and parasite (O&P) exam is used to detect the presence of ...

  11. Parasites and food: ripe for exploitation.

    Science.gov (United States)

    Thompson, R C Andrew

    2014-01-01

    Parasites are often exploited for emotive or political purposes. This is especially so for a number of foodborne parasitic zoonoses, where this exploitation may not necessarily best serve the public good.

  12. Can Parasites Really Reveal Environmental Impact?

    Science.gov (United States)

    This review assesses the usefulness of parasites as bioindicators of environmental impact. Relevant studies published in the past decade were compiled; factorial meta-analysis demonstrated significant effects and interactions between parasite levels and the presence and concentra...

  13. Sacral Rachipagus Parasite: A Case Report

    Directory of Open Access Journals (Sweden)

    Kamal Nain Rattan

    2016-03-01

    Full Text Available We are reporting a case of sacral rachipagus parasite which was vaginally delivered as a large irregular mass attached to the sacral region by a vascular pedicle. This case was managed successfully by surgical excision of parasite.

  14. Parasitic Nematode Interactions with Mammals and Plants

    NARCIS (Netherlands)

    Jasmer, D.P.; Goverse, A.; Smant, G.

    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

  15. Parasitic Diseases - Multiple Languages: MedlinePlus

    Science.gov (United States)

    ... Are Here: Home → Multiple Languages → All Health Topics → Parasitic Diseases URL of this page: https://medlineplus.gov/languages/ ... V W XYZ List of All Topics All Parasitic Diseases - Multiple Languages To use the sharing features on ...

  16. Copepoda parasites in economically important fish, Mugilidae ...

    African Journals Online (AJOL)

    FUNMILAYO

    parasites are ecto-parasites which negatively affect the appearance and reduced production of species of economically ... pathogenic problems in cultured mullet fish in marine and brackish ..... pollution resulting from the human settlement.

  17. Antimicrobial peptide action on parasites.

    Science.gov (United States)

    Torrent, Marc; Pulido, David; Rivas, Luis; Andreu, David

    2012-08-01

    Diseases caused by protozoan parasites can pose a severe thread to human health and are behind some serious neglected tropical diseases like malaria and leishmaniasis. Though several different drugs have been developed in order to eradicate these diseases, a successful candidate has not yet been discovered. Among the most active compounds tested, antimicrobial peptides (AMPs) are particularly appealing because of their wide spectrum of action. AMPs have been described to perturb protozoan homeostasis by disrupting the cellular membranes but also by interfering with key processes in the parasite metabolism. In this review we describe the diverse mechanisms of action of AMPs on protozoan targets and how they can be exploited to treat diseases. Moreover, we describe with detail the antimicrobial action of AMPs on two major parasitical infections: leishmaniasis and malaria. All the features reviewed here show that AMPs are promising drugs to target protozoan parasites and that further understanding of the mechanism of action of these compounds will lead to improved drugs that could be worth to test in a clinical phase.

  18. Zoology: Invertebrates that Parasitize Invertebrates.

    Science.gov (United States)

    Giribet, Gonzalo

    2016-07-11

    The genome of an orthonectid, a group of highly modified parasitic invertebrates, is drastically reduced and compact, yet it shows the bilaterian gene toolkit. Phylogenetic analyses place the enigmatic orthonectids within Spiralia, although their exact placement remains uncertain. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Parasitism and mutualism in Wolbachia

    DEFF Research Database (Denmark)

    Bordenstein, Seth R; Paraskevopoulos, Charalampos; Dunning Hotopp, Julie C;

    2009-01-01

    Ecological and evolutionary theories predict that parasitism and mutualism are not fixed endpoints of the symbiotic spectrum. Rather, parasitism and mutualism may be host or environment dependent, induced by the same genetic machinery, and shifted due to selection. These models presume the existe......Ecological and evolutionary theories predict that parasitism and mutualism are not fixed endpoints of the symbiotic spectrum. Rather, parasitism and mutualism may be host or environment dependent, induced by the same genetic machinery, and shifted due to selection. These models presume...... the existence of genetic or environmental variation that can spur incipient changes in symbiotic lifestyle. However, for obligate intracellular bacteria whose genomes are highly reduced, studies specify that discrete symbiotic associations can be evolutionarily stable for hundreds of millions of years...... in symbiotic lifestyle with a comprehensive, phylogenomic analysis. Contrary to previous claims, we show unequivocally that the transition in lifestyle cannot be reconstructed with current methods due to long-branch attraction (LBA) artifacts of the distant Anaplasma and Ehrlichia outgroups. Despite the use...

  20. Decoys in Predation and Parasitism

    NARCIS (Netherlands)

    Wilkinson, Michael H.F.

    2003-01-01

    Predator-prey or host-parasite dynamics can be altered by the presence of other species through several mechanisms. One such mechanism is the ‘‘decoy effect,’’ which itself can take a variety of forms. In its simplest form, the third species, which is inedible to the predator, nonetheless interferes

  1. Decoys in Predation and Parasitism

    NARCIS (Netherlands)

    Wilkinson, Michael H.F.

    2003-01-01

    Predator-prey or host-parasite dynamics can be altered by the presence of other species through several mechanisms. One such mechanism is the ‘‘decoy effect,’’ which itself can take a variety of forms. In its simplest form, the third species, which is inedible to the predator, nonetheless interferes

  2. The kinomes of apicomplexan parasites

    OpenAIRE

    Miranda-Saavedra, D.; Gabaldón, T.; Barton, G; Langsley, G; Doerig, C.

    2012-01-01

    Protein phosphorylation plays a fundamental role in the biology of apicomplexan parasites. Many apicomplexan protein kinases are substantially different from their mammalian orthologues, and thus constitute a landscape of potential drug targets. Here, we integrate genomic, biochemical, genetic and evolutionary information to provide an integrated and up-to-date analysis of twelve apicomplexan kinomes. All kinome sequences are available through the Kinomer database.

  3. In vitro biomarker discovery in the parasitic flatworm Fasciola hepatica for monitoring chemotherapeutic treatment

    Directory of Open Access Journals (Sweden)

    Russell M. Morphew

    2014-06-01

    Full Text Available The parasitic flatworm Fasciola hepatica is a global food security risk. With no vaccines, the sustainability of triclabendazole (TCBZ is threatened by emerging resistance. F. hepatica excretory/secretory (ES products can be detected in host faeces and used to estimate TCBZ success and failure. However, there are no faecal based molecular diagnostics dedicated to assessing drug failure or resistance to TCBZ in the field. Utilising in vitro maintenance and sub-proteomic approaches two TCBZ stress ES protein response fingerprints were identified: markers of non-killing and lethal doses. This study provides candidate protein/peptide biomarkers to validate for detection of TCBZ failure and resistance.

  4. Emerging parasitic diseases of sheep.

    Science.gov (United States)

    Taylor, M A

    2012-09-30

    There have been changes in the emergence and inability to control of a number of sheep parasitic infections over the last decade. This review focuses on the more globally important sheep parasites, whose reported changes in epidemiology, occurrence or failure to control are becoming increasingly evident. One of the main perceived driving forces is climate change, which can have profound effects on parasite epidemiology, especially for those parasitic diseases where weather has a direct effect on the development of free-living stages. The emergence of anthelmintic-resistant strains of parasitic nematodes and the increasing reliance placed on anthelmintics for their control, can exert profound changes on the epidemiology of those nematodes causing parasitic gastroenteritis. As a consequence, the effectiveness of existing control strategies presents a major threat to sheep production in many areas around the world. The incidence of the liver fluke, Fasciola hepatica, is inextricably linked to high rainfall and is particularly prevalent in high rainfall years. Over the last few decades, there have also been increasing reports of other fluke associated diseases, such as dicroceliosis and paramphistomosis, in a number of western European countries, possibly introduced through animal movements, and able to establish with changing climates. External parasite infections, such as myiasis, can cause significant economic loss and presents as a major welfare problem. The range of elevated temperatures predicted by current climate change scenarios, result in an elongated blowfly season with earlier spring emergence and a higher cumulative incidence of fly strike. Additionally, legislative decisions leading to enforced changes in pesticide usage and choices have resulted in increased reports and spread of ectoparasitic infections, particularly mite, lice and tick infestations in sheep. Factors, such as dip disposal and associated environmental concerns, and, perhaps more

  5. 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

  6. Canine and feline parasitic zoonoses in China

    OpenAIRE

    2012-01-01

    Abstract Canine and feline parasitic zoonoses have not been given high priority in China, although the role of companion animals as reservoirs for zoonotic parasitic diseases has been recognized worldwide. With an increasing number of dogs and cats under unregulated conditions in China, the canine and feline parasitic zoonoses are showing a trend towards being gradually uncontrolled. Currently, canine and feline parasitic zoonoses threaten human health, and cause death and serious diseases in...

  7. Review of Parasitic Zoonoses in Egypt

    OpenAIRE

    2014-01-01

    This review presents a comprehensive picture of the zoonotic parasitic diseases in Egypt, with particular reference to their relative prevalence among humans, animal reservoirs of infection, and sources of human infection. A review of the available literature indicates that many parasitic zoonoses are endemic in Egypt. Intestinal infections of parasitic zoonoses are widespread and are the leading cause of diarrhea, particularly among children and residents of rural areas. Some parasitic zoono...

  8. Parasite control in transhumant situations.

    Science.gov (United States)

    Eckert, J; Hertzberg, H

    1994-08-01

    Transhumance is defined as 'seasonal moving of livestock to regions of different climate'. It is an integral part of livestock production in many parts of the world and takes several forms including moving of livestock from lowland to mountainous pastures or from dry to humid areas. The impact of transhumance on parasite populations of livestock and on parasite control is described, mainly using examples from Europe. The epidemiology of trichostrongylidosis of cattle, mainly caused by Ostertagia ostertagi and Cooperia oncophora, is characterised by prolonged survival of overwintered infective larvae until the end of June. Cattle moved to such contaminated pastures in a transhumant grazing system are exposed to these larvae and may be protected, during the second half of the grazing season until autumn, by a late application (June/July) of an intraruminal drug-release device. Community pastures used in a transhumant system with mixed grazing of young cattle originating from various farms may enhance transmission of dictyocaulosis. Therefore, specific prophylactic measures are required. Hill sheep nematode populations may differ from those in lowland sheep in that Haemonchus contortus generally plays a minor role in hill sheep in which Ostertagia circumcincta and Nematodirus spp. predominate. Infections with Fasciola hepatica and Dicrocoelium dendriticum can be acquired on mountainous pastures by cattle, sheep and other livestock grazing in a transhumant system as intermediate hosts of these parasites may find suitable habitats in these regions. There is evidence that in the prealpine and alpine area both parasites are mainly transmitted in two-season cycles. Further examples for the impact of transhumance on parasite-host inter-relationships include cysticercosis in cattle, echinococcosis, psoroptic manage in sheep, tick-borne fever of cattle, and hypodermosis in cattle. These are described and discussed.

  9. Functional diversity of non-lethal effects, chemical camouflage, and variation in fish avoidance in colonizing beetles.

    Science.gov (United States)

    Resetarits, William J; Pintar, Matthew R

    2016-12-01

    Predators play an extremely important role in natural communities. In freshwater systems, fish can dominate sorting both at the colonization and post-colonization stage. Specifically, for many colonizing species, fish can have non-lethal, direct effects that exceed the lethal direct effects of predation. Functionally diverse fish species with a range of predatory capabilities have previously been observed to elicit functionally equivalent responses on oviposition in tree frogs. We tested this hypothesis of functional equivalence of non-lethal effects for four predatory fish species, using naturally colonizing populations of aquatic beetles. Among taxa other than mosquitoes, and with the exception of the chemically camouflaged pirate perch, Aphredoderus sayanus, we provide the first evidence of variation in colonization or oviposition responses to different fish species. Focusing on total abundance, Fundulus chrysotus, a gape-limited, surface-feeding fish, elicited unique responses among colonizing Hydrophilidae, with the exception of the smallest and most abundant taxa, Paracymus, while Dytiscidae responded similarly to all avoided fish. Neither family responded to A. sayanus. Analysis of species richness and multivariate characterization of the beetle assemblages for the four fish species and controls revealed additional variation among the three avoided species and confirmed that chemical camouflage in A. sayanus results in assemblages essentially identical to fishless controls. The origin of this variation in beetle responses to different fish is unknown, but may involve variation in cue sensitivity, different behavioral algorithms, or differential responses to species-specific fish cues. The identity of fish species occupying aquatic habitats is crucial to understanding community structure, as varying strengths of lethal and non-lethal effects, as well as their interaction, create complex landscapes of predator effects and challenge the notion of functional

  10. Parasitic infections of the gastrointestinal tract.

    Science.gov (United States)

    Noyer, C M; Brandt, L J

    1999-08-01

    Parasitic infections of the gastrointestinal tract are a major cause of morbidity and mortality worldwide. Increased international travel means that gastroenterologists are now more likely to care for patients with parasitic diseases. This article reviews various aspects of the more common intestinal parasites and their infections, including epidemiology, life cycle, pathogenesis, clinical manifestations, diagnosis, and treatment.

  11. Immigration, parasitic infection, and United States religiosity.

    Science.gov (United States)

    Wall, Jaimie N; Shackelford, Todd K

    2012-04-01

    Fincher & Thornhill (F&T) present a powerful case for the relationship between parasite-stress and religiosity. We argue, however, that the United States may be more religious than can be accounted for by parasite-stress. This greater religiosity might be attributable to greater sensitivity to immigration, which may hyperactivate evolved mechanisms that motivate avoidance of potential carriers of novel parasites.

  12. Human behaviour and the epidemiology of parasitic zoonoses.

    Science.gov (United States)

    Macpherson, Calum N L

    2005-10-01

    The behaviour of Homo sapiens has a pivotal role to play in the macro and microepidemiology of emerging or re-emerging parasitic zoonoses. Changing demographics and the concomitant alterations to the environment, climate, technology, land use and changes in human behavior, converge to favour the emergence and spread of parasitic zoonoses. The recent unprecedented movements of people, their animals and their parasites around the world, introduce and mix genes, cultural preferences, customs, and behavioral patterns. The increasing proclivity for eating meat, fish, crabs, shrimp, molluscs raw, undercooked, smoked, pickled or dried facilitates a number of protozoan (Toxoplasma), trematode (Fasciola sp., Paragonimus spp., Clonorchis sp., Opisthorchis spp., Heterophyes sp., Metagonimus sp., Echinostoma spp., Nanophyetus sp.) cestode (Taenia spp, Diphyllobothrum sp.) and nematode (Trichinella spp., Capillaria spp., Gnathostoma spp., Anisakis sp., Parastrongylus spp.) caused zoonoses. The increasing world population and the inability to keep pace with the provision of adequate sanitation and clean, safe drinking water, has led to an increased importance of waterborne zoonoses, such as those caused by Giardia, Cryptosporidium and Toxoplasma. Our close relationship with and the numerous uses to which we put companion animals and their ubiquitous distribution has resulted in dogs and cats unwitting participation in sharing over 60 parasite species including: Giardia, Cryptosporidium, Toxoplasma, most foodborne trematode species, Diphyllobothrum, Echinococcus spp., Ancylostoma and Toxocara. Changing human behaviour through education, to encourage the proper cooking of food, which may have cultural and social significance, will remain as challenging as controlling stray and feral pet populations, improving hygiene levels and the provision of safe drinking water and the proper use of sanctuary facilities. Long pre-patent periods and the normally insidious sub-clinical nature of

  13. A hepatic protein, fetuin-A, occupies a protective role in lethal systemic inflammation.

    Directory of Open Access Journals (Sweden)

    Wei Li

    Full Text Available BACKGROUND: A liver-derived protein, fetuin-A, was first purified from calf fetal serum in 1944, but its potential role in lethal systemic inflammation was previously unknown. This study aims to delineate the molecular mechanisms underlying the regulation of hepatic fetuin-A expression during lethal systemic inflammation (LSI, and investigated whether alterations of fetuin-A levels affect animal survival, and influence systemic accumulation of a late mediator, HMGB1. METHODS AND FINDINGS: LSI was induced by endotoxemia or cecal ligation and puncture (CLP in fetuin-A knock-out or wild-type mice, and animal survival rates were compared. Murine peritoneal macrophages were challenged with exogenous (endotoxin or endogenous (IFN-γ stimuli in the absence or presence of fetuin-A, and HMGB1 expression and release was assessed. Circulating fetuin-A levels were decreased in a time-dependent manner, starting between 26 h, reaching a nadir around 24-48 h, and returning towards base-line approximately 72 h post onset of endotoxemia or sepsis. These dynamic changes were mirrored by an early cytokine IFN-γ-mediated inhibition (up to 50-70% of hepatic fetuin-A expression. Disruption of fetuin-A expression rendered animals more susceptible to LSI, whereas supplementation of fetuin-A (20-100 mg/kg dose-dependently increased animal survival rates. The protection was associated with a significant reduction in systemic HMGB1 accumulation in vivo, and parallel inhibition of IFN-γ- or LPS-induced HMGB1 release in vitro. CONCLUSIONS: These experimental data suggest that fetuin-A is protective against lethal systemic inflammation partly by inhibiting active HMGB1 release.

  14. The "Lethal Chamber": Further Evidence of the Euthanasia Option.

    Science.gov (United States)

    Elks, Martin A.

    1993-01-01

    Historical discussions of the euthanasia or "lethal chamber" option in relation to people with mental retardation are presented. The paper concludes that eugenic beliefs in the primacy of heredity over environment and the positive role of natural selection may have condoned the poor conditions characteristic of large, segregated institutions and…

  15. Dominant-lethal mutations and heritable translocations in mice

    Energy Technology Data Exchange (ETDEWEB)

    Generoso, W.M.

    1983-01-01

    Chromosome aberrations are a major component of radiation or chemically induced genetic damage in mammalian germ cells. The types of aberration produced are dependent upon the mutagen used and the germ-cell stage treated. For example, in male meiotic and postmeiotic germ cells certain alkylating chemicals induce both dominant-lethal mutations and heritable translocations while others induce primarily dominant-lethal mutations. Production of these two endpoints appears to be determined by the stability of alkylation products with the chromosomes. If the reaction products are intact in the male chromosomes at the time of sperm entry, they may be repaired in fertilized eggs. If repair is not effected and the alkylation products persist to the time of pronuclear chromosome replication, they lead to chromatid-type aberrations and eventually to dominant-lethality. The production of heritable translocations, on the other hand, requires a transformation of unstable alkylation products into suitable intermediate lesions. The process by which these lesions are converted into chromosome exchange within the male genome takes place after sperm enters the egg but prior to the time of pronuclear chromosome replication (i.e., chromosome-type). Thus, dominant-lethal mutations result from both chromatid- and chromosome-type aberrations while heritable translocations result primarily from the latter type. DNA target sites associated with the production of these two endpoints are discussed.

  16. Evaluation of lethality estimates for combustion gases in military scenarios.

    Science.gov (United States)

    Smith, S M; Stuhmiller, J H; Januszkiewicz, A J

    1996-12-31

    To meet the military objective of determining criteria for incapacitation and lethality from toxic gas exposures, a series of small animal tests and data analyses were conducted. Carbon monoxide (CO), a narcotic gas and nitrogen dioxide (NO2), an irritant gas, along with carbon dioxide (CO2) were tested individually and in the following mixtures: (CO + CO2), (NO2 + CO2) and (NO2 + CO + CO2). A group of six animals was exposed to each of the gases and their combinations, lethality and biophysical data were collected. We conclude that our observations of lethality from single toxic gases can be correlated with a fractional effective dose (FED) description, in which external concentrations are corrected for minute volume changes. Multiple gas exposures clearly demonstrate synergistic effects because lethality rates greatly exceed those expected from statistically independent causes. Simple addition of the FED values, however, overstates the effect and implies a competition between the narcotic and irritant gas effects. The N-Gas model, while being an additive FED model, does not appear to be in a form that could guide the setting of military exposure standards.

  17. The Lethal "Femme Fatale" in the Noir Tradition.

    Science.gov (United States)

    Boozer, Jack

    2000-01-01

    Traces the lethal seductress through Hollywood's "noir" history from "Double Indemnity" (1944) to "The Last Seduction" (1996). Examines how this figure largely abjures traditional romance and passive domesticity, choosing instead to apply her sexuality to homicidal plots toward greed. Argues that her narrative positioning serves as a barometer of…

  18. Papaya Lethal Yellowing Virus (PLYV) Infects Vasconcellea cauliflora

    NARCIS (Netherlands)

    Amaral, P.P.R.; Resende, de R.O.; Souza, M.T.

    2006-01-01

    Papaya lethal yellowing virus (PLYV) é um dos três vírus descritos infectando mamoeiros (Carica papaya L.) no Brasil. Vasconcellea cauliflora (Jacq.) A. DC., antes denominada de Carica cauliflora (Jacq.), é uma reconhecida fonte de resistência natural ao Papaya ringspot virus (PRSV), causador da "Ma

  19. The Lethal "Femme Fatale" in the Noir Tradition.

    Science.gov (United States)

    Boozer, Jack

    2000-01-01

    Traces the lethal seductress through Hollywood's "noir" history from "Double Indemnity" (1944) to "The Last Seduction" (1996). Examines how this figure largely abjures traditional romance and passive domesticity, choosing instead to apply her sexuality to homicidal plots toward greed. Argues that her narrative…

  20. The Prevalence, Lethality and Intent of Suicide Attempts among Adolescents.

    Science.gov (United States)

    Andrews, Judy A.; Lewinsohn, Peter M.

    Although suicide is the second leading cause of death among adolescents in the United States, little is known about the prevalence or characteristics of suicide attempts among adolescents. Data from 1,710 adolescents attending 9 high schools in 5 communities were examined to determine the prevalence of suicide attempts and the lethality and intent…

  1. Conditional lethality strains for the biological control of Anastrepha species

    Science.gov (United States)

    Pro-apoptotic cell death genes are promising candidates for biologically-based autocidal control of pest insects as demonstrated by tetracycline (tet)-suppressible systems for conditional embryonic lethality in Drosophila melanogaster (Dm) and the medfly, Ceratitis capitata (Cc). However, for medfly...

  2. The "Lethal Chamber": Further Evidence of the Euthanasia Option.

    Science.gov (United States)

    Elks, Martin A.

    1993-01-01

    Historical discussions of the euthanasia or "lethal chamber" option in relation to people with mental retardation are presented. The paper concludes that eugenic beliefs in the primacy of heredity over environment and the positive role of natural selection may have condoned the poor conditions characteristic of large, segregated institutions and…

  3. Activated protein C ameliorates Bacillus anthracis lethal toxin-induced lethal pathogenesis in rats

    Directory of Open Access Journals (Sweden)

    Kau Jyh-Hwa

    2012-11-01

    Full Text Available Abstract Background Lethal toxin (LT is a major virulence factor of Bacillus anthracis. Sprague Dawley rats manifest pronounced lung edema and shock after LT treatments, resulting in high mortality. The heart failure that is induced by LT has been suggested to be a principal mechanism of lung edema and mortality in rodents. Since LT-induced death occurs more rapidly in rats than in mice, suggesting that other mechanisms in addition to the heart dysfunction may be contributed to the fast progression of LT-induced pathogenesis in rats. Coagulopathy may contribute to circulatory failure and lung injury. However, the effect of LT on coagulation-induced lung dysfunction is unclear. Methods To investigate the involvement of coagulopathy in LT-mediated pathogenesis, the mortality, lung histology and coagulant levels of LT-treated rats were examined. The effects of activated protein C (aPC on LT-mediated pathogenesis were also evaluated. Results Fibrin depositions were detected in the lungs of LT-treated rats, indicating that coagulation was activated. Increased levels of plasma D-dimer and thrombomodulin, and the ameliorative effect of aPC further suggested that the activation of coagulation-fibrinolysis pathways plays a role in LT-mediated pathogenesis in rats. Reduced mortality was associated with decreased plasma levels of D-dimer and thrombomodulin following aPC treatments in rats with LT-mediated pathogenesis. Conclusions These findings suggest that the activation of coagulation in lung tissue contributes to mortality in LT-mediated pathogenesis in rats. In addition, anticoagulant aPC may help to develop a feasible therapeutic strategy.

  4. Postcolonial Ecologies of Parasite and Host: Making Parasitism Cosmopolitan.

    Science.gov (United States)

    Anderson, Warwick

    2016-04-01

    The interest of F. Macfarlane Burnet in host-parasite interactions grew through the 1920s and 1930s, culminating in his book, Biological Aspects of Infectious Disease (1940), often regarded as the founding text of disease ecology. Our knowledge of the influences on Burnet's ecological thinking is still incomplete. Burnet later attributed much of his conceptual development to his reading of British theoretical biology, especially the work of Julian Huxley and Charles Elton, and regretted he did not study Theobald Smith's Parasitism and Disease (1934) until after he had formulated his ideas. Scholars also have adduced Burnet's fascination with natural history and the clinical and public health demands on his research effort, among other influences. I want to consider here additional contributions to Burnet's ecological thinking, focusing on his intellectual milieu, placing his research in a settler society with exceptional expertise in environmental studies and pest management. In part, an ''ecological turn'' in Australian science in the 1930s, derived to a degree from British colonial scientific investments, shaped Burnet's conceptual development. This raises the question of whether we might characterize, in postcolonial fashion, disease ecology, and other studies of parasitism, as successful settler colonial or dominion science.

  5. Annotating novel genes by integrating synthetic lethals and genomic information

    Directory of Open Access Journals (Sweden)

    Faty Mahamadou

    2008-01-01

    Full Text Available Abstract Background Large scale screening for synthetic lethality serves as a common tool in yeast genetics to systematically search for genes that play a role in specific biological processes. Often the amounts of data resulting from a single large scale screen far exceed the capacities of experimental characterization of every identified target. Thus, there is need for computational tools that select promising candidate genes in order to reduce the number of follow-up experiments to a manageable size. Results We analyze synthetic lethality data for arp1 and jnm1, two spindle migration genes, in order to identify novel members in this process. To this end, we use an unsupervised statistical method that integrates additional information from biological data sources, such as gene expression, phenotypic profiling, RNA degradation and sequence similarity. Different from existing methods that require large amounts of synthetic lethal data, our method merely relies on synthetic lethality information from two single screens. Using a Multivariate Gaussian Mixture Model, we determine the best subset of features that assign the target genes to two groups. The approach identifies a small group of genes as candidates involved in spindle migration. Experimental testing confirms the majority of our candidates and we present she1 (YBL031W as a novel gene involved in spindle migration. We applied the statistical methodology also to TOR2 signaling as another example. Conclusion We demonstrate the general use of Multivariate Gaussian Mixture Modeling for selecting candidate genes for experimental characterization from synthetic lethality data sets. For the given example, integration of different data sources contributes to the identification of genetic interaction partners of arp1 and jnm1 that play a role in the same biological process.

  6. [Clinical microbiology laboratory and imported parasitic diseases].

    Science.gov (United States)

    Martín-Rabadán, Pablo; Martínez-Ruiz, Rocío; Cuadros, Juan; Cañavate, Carmen

    2010-12-01

    Imported parasitosis represents an increasingly frequent diagnostic challenge for microbiology laboratories. A surge in immigration and international travel has led to a rise in the number of imported cases of parasitosis, and this trend is expected to continue in the future. The present article addresses this challenge by reviewing recommended diagnostic approaches and tests. Currently, microscopy is always recommended when analysing blood samples for parasites. If malaria is suspected, rapid antigen testing (including at least HRP2 antigen) should also be performed. The work-up for suspected leishmaniasis should include serology, culture, and in selected cases detection of antigen in urine. In suspected Chagas disease, two different serological tests should be performed. PCR for blood protozoa is highly sensitive, although it cannot be used to rule out Chagas disease, since this condition may be present without parasitemia. Accurate diagnosis of intestinal amebiasis usually requires PCR or antigen detection tests. In helminthiasis, traditional microscopy may need to be complemented with other tests, such as agar plate culture for strongyloidiasis, Og4C3 antigen detection for bancroftian filariasis, and antibody detection test for filariasis and schistosomiasis.

  7. Lethal action of the nitrothiazolyl-salicylamide derivative nitazoxanide via induction of oxidative stress in Leishmania (L.) infantum.

    Science.gov (United States)

    Mesquita, Juliana Tonini; Pinto, Erika Gracielle; Taniwaki, Noemi Nosomi; Galisteo, Andres Jimenez; Tempone, Andre Gustavo

    2013-12-01

    Studying the cellular death pathways in Leishmania is an important aspect of discovering new antileishmanials. While using a drug repositioning approach, the lethal action of the nitrothiazolyl-salicylamide derivative nitazoxanide (NTZ) was investigated against Leishmania (L.) infantum. The in vitro antileishmanial activity and cytotoxicity were assessed using both parasite stages and mammalian NCTC cells, respectively. The lethal action of NTZ was investigated by detecting the phosphatidylserine (PS) exposure, reactive oxygen species (ROS) regulation, plasma membrane permeability, mitochondrial membrane potential and ultrastructural modifications by transmission electron microscopy. NTZ's activity against L. infantum was confirmed, producing IC50 values of 42.71μg/mL against promastigotes and 6.78μg/mL against intracellular amastigotes. NTZ rapidly altered the cellular metabolism of promastigotes by depolarising the mitochondrial membrane and up-regulating the reactive oxygen species (ROS). In addition, the flow cytometry data revealed an intense and time-dependent exposure of PS in promastigotes. When using SYTOX(®) Green as a fluorescent probe, NTZ demonstrated no interference in plasma membrane permeability. The ultrastructural alterations in promastigotes were time-dependent and caused chromatin condensation, plasma membrane blebbing and mitochondrial swelling. These data suggest that NTZ induced oxidative stress in L. (L.) infantum and might be a useful compound for investigating new therapeutic targets.

  8. A conditionally lethal mutant of Salmonella Typhimurium induces a protective response in mice.

    Science.gov (United States)

    Hidalgo, Alejandro A; Villagra, Nicolás A; Jerez, Sebastián A; Fuentes, Juan A; Mora, Guido C

    2016-02-01

    Here we present the design of a conditionally lethal mutant of Salmonella enterica serovar Typhimurium (S. Typhimurium) which growth depends on tetracycline (Tet). Four mutants of S. Typhimurium, with Tet-conditional growth, were created by inserting the tetRA cassette. Three of the mutants presented a conditional-lethal phenotype in vitro. One mutant in the yabB gene remained conditional inside cells and did not persisted after 24 h in cell cultures. The capacity of S. Typhimurium yabB::tetRA to invade deep organs was investigated in intraperitoneally (IP) infected mice fed with or without chlortetracycline (CTet), a Tet analog with lower antibiotic activity. The yabB::tetRA mutant was undetectable in liver or spleen of animals under normal diet, while in mice under diet including CTet, yabB::tetRA invaded at a level comparable to the WT in mice under normal diet. Moreover, yabB::tetRA produced a strong humoral-immunoresponse after one IP immunization with 10(6) bacteria, measured as serum reactivity against S. Typhimurium whole cell extract. By contrast, oral immunization with 10(6) bacteria was weaker and variable on inducing antibodies. Consistently, IP infected mice were fully protected in a challenge with 10(4) oral S. Typhimurium, while protection was partial in orally immunized mice. Our data indicate that S. Typhimurium yabB::tetRA is a conditionally attenuated strain capable of inducing a protective response in mice in non-permissive conditions.

  9. Noninvasive risk stratification of lethal ventricular arrhythmias and sudden cardiac death after myocardial infarction

    Directory of Open Access Journals (Sweden)

    Kenji Yodogawa, MD

    2014-08-01

    Full Text Available Prediction of lethal ventricular arrhythmias leading to sudden cardiac death is one of the most important and challenging problems after myocardial infarction (MI. Identification of MI patients who are prone to ventricular tachyarrhythmias allows for an indication of implantable cardioverter-defibrillator placement. To date, noninvasive techniques such as microvolt T-wave alternans (MTWA, signal-averaged electrocardiography (SAECG, heart rate variability (HRV, and heart rate turbulence (HRT have been developed for this purpose. MTWA is an indicator of repolarization abnormality and is currently the most promising risk-stratification tool for predicting malignant ventricular arrhythmias. Similarly, late potentials detected by SAECG are indices of depolarization abnormality and are useful in risk stratification. However, the role of SAECG is limited because of its low predictive accuracy. Abnormal HRV and HRT patterns reflect autonomic disturbances, which may increase the risk of lethal ventricular arrhythmias, but the existing evidence is insufficient. Further studies of noninvasive assessment may provide a new insight into risk stratification in post-MI patients.

  10. The angiotensin-converting enzyme inhibitor captopril rescues mice from endotoxin-induced lethal hepatitis.

    Science.gov (United States)

    Ge, Pu; Jiang, Rong; Yao, Xin; Li, Jing; Dai, Jie; Zhang, Li; Ye, Bin

    2017-02-01

    The renin-angiotensin system is classically regarded as a crucial regulator of circulatory homeostasis, but recent studies also revealed its pro-inflammatory roles. The beneficial effects of the angiotensin-converting enzyme inhibitor (ACEI) in severe inflammatory injury in the lung and heart have been previously reported, but its potential effects on lethal hepatitis were unknown. In this study, a mouse model with LPS/d-galactosamine (GalN)-induced fulminant hepatitis were used to test the protective potential of captopril, a representative ACEI. The results indicated that treatment with captopril significantly decreased the plasma level of alanine aminotransferase and aspartate aminotransferase, alleviated the histopathological damage of the liver tissue and improve the survival rate of LPS/GalN-challenged mice. These effects were accompanied by reduced mRNA levels of TNF-α and IL-6 in the liver, and decreased protein level of TNF-α and IL-6 in the plasma. In addition, the activation of caspases 3, 8 and 9, and the presence of TUNEL-positive apoptotic cells, were also suppressed by captopril treatment. The above evidence suggested that the renin-angiotensin system might be involved in the development of LPS/GalN-induced fulminant hepatitis and ACEI might have potential value in lethal hepatitis.

  11. Hidden in plain sight: Cryptic and endemic malaria parasites in North American white-tailed deer (Odocoileus virginianus).

    Science.gov (United States)

    Martinsen, Ellen S; McInerney, Nancy; Brightman, Heidi; Ferebee, Ken; Walsh, Tim; McShea, William J; Forrester, Tavis D; Ware, Lisa; Joyner, Priscilla H; Perkins, Susan L; Latch, Emily K; Yabsley, Michael J; Schall, Joseph J; Fleischer, Robert C

    2016-02-01

    Malaria parasites of the genus Plasmodium are diverse in mammal hosts, infecting five mammalian orders in the Old World, but were long considered absent from the diverse deer family (Cervidae) and from New World mammals. There was a description of a Plasmodium parasite infecting a single splenectomized white-tailed deer (WTD; Odocoileus virginianus) in 1967 but none have been reported since, which has proven a challenge to our understanding of malaria parasite biogeography. Using both microscopy and polymerase chain reaction, we screened a large sample of native and captive ungulate species from across the United States for malaria parasites. We found a surprisingly high prevalence (up to 25%) and extremely low parasitemia of Plasmodium parasites in WTD throughout the eastern United States. We did not detect infections in the other ungulate species nor in western WTD. We also isolated the parasites from the mosquito Anopheles punctipennis. Morphologically, the parasites resemble the parasite described in 1967, Plasmodium odocoilei. Our analysis of the cytochrome b gene revealed two divergent Plasmodium clades in WTD representative of species that likely diverged 2.3 to 6 million years ago, concurrent with the arrival of the WTD ancestor into North America across Beringia. Multigene phylogenetic analysis placed these clades within the larger malaria parasite clade. We document Plasmodium parasites to be common in WTD, endemic to the New World, and as the only known malaria parasites from deer (Cervidae). These findings reshape our knowledge of the phylogeography of the malaria parasites and suggest that other mammal taxa may harbor infection by endemic and occult malaria parasites.

  12. Antibodies against recombinant catalytic domain of lethal toxin of Clostridium sordellii neutralize lethal toxin toxicity in HeLa cells.

    Science.gov (United States)

    Arya, Preetika; Ponmariappan, S; Singh, Lokendra; Prasad, G B K S

    2013-02-01

    Lethal toxin of Clostridium sordellii (MLD 150 ng/kg) is one of the most potent Clostridial toxins and is responsible for most of the diseases including sudden death syndrome in cattle, sheep and toxic shock syndrome, necrotizing faciitis, neonatal omphalitis and gangrene in humans. Lethal toxin (TcsL) is a single chain protein of about 270 kDa. In the present study, 1.6 kb DNA fragment encoding for the catalytic domain of TcsL was PCR amplified, cloned in pQE30 UA vector and expressed in E. coli SG 13009. The expression of recombinant lethal toxin protein (rTcsL) was optimized and it was purified under native conditions using a single step Ni-NTA affinity chromatography. The purified recombinant protein was used for the production of polyclonal antibodies in mice and rabbit. The raised antibodies reacted specifically with the purified rTcsL and intact native lethal toxin on Western blot. The biological activity of the recombinant protein was tested in HeLa cells where it showed the cytotoxicity. Further, the polyclonal antibodies were used for in-vitro neutralization of purified rTcsL, acid precipitated C. sordellii and C. difficile native toxins in HeLa cells. Mice and rabbit anti-rTcsL sera effectively neutralized the cytotoxicity of rTcsL and C. sordellii native toxin but it did not neutralize the cytotoxicity of C. difficile toxin in HeLa cells.

  13. 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...

  14. Moonlighting enzymes in parasitic protozoa.

    Science.gov (United States)

    Collingridge, Peter W; Brown, Robert W B; Ginger, Michael L

    2010-08-01

    Enzymes moonlight in a non-enzymatic capacity in a diverse variety of cellular processes. The discovery of these non-enzymatic functions is generally unexpected, and moonlighting enzymes are known in both prokaryotes and eukaryotes. Importantly, this unexpected multi-functionality indicates that caution might be needed on some occasions in interpreting phenotypes that result from the deletion or gene-silencing of some enzymes, including some of the best known enzymes from classic intermediary metabolism. Here, we provide an overview of enzyme moonlighting in parasitic protists. Unequivocal and putative examples of moonlighting are discussed, together with the possibility that the unusual biological characteristics of some parasites either limit opportunities for moonlighting to arise or perhaps contribute to the evolution of novel proteins with clear metabolic ancestry.

  15. Parasitic interference in nulling interferometry

    CERN Document Server

    Matter, Alexis; Danchi, William C; Lopez, Bruno; Absil, Olivier

    2013-01-01

    Nulling interferometry aims to detect faint objects close to bright stars. Its principle is to produce a destructive interference along the line-of-sight so that the stellar flux is rejected, while the flux of the off-axis source can be transmitted. In practice, various instrumental perturbations can degrade the nulling performance. Any imperfection in phase, amplitude, or polarization produces a spurious flux that leaks to the interferometer output and corrupts the transmitted off-axis flux. One of these instrumental pertubations is the crosstalk phenomenon, which occurs because of multiple parasitic reflections inside transmitting optics, and/or diffraction effects related to beam propagation along finite size optics. It can include a crosstalk of a beam with itself, and a mutual crosstalk between different beams. This can create a parasitic interference pattern, which degrades the intrinsic transmission map - or intensity response - of the interferometer. In this context, we describe how this instrumental ...

  16. Gene targeting in malaria parasites.

    Science.gov (United States)

    Ménard, R; Janse, C

    1997-10-01

    Gene targeting, which permits alteration of a chosen gene in a predetermined way by homologous recombination, is an emerging technology in malaria research. Soon after the development of techniques for stable transformation of red blood cell stages of Plasmodium falciparum and Plasmodium berghei, genes of interest were disrupted in the two species. The main limitations of gene targeting in malaria parasites result from the intracellular growth and slow replication of these parasites. On the other hand, the technology is facilitated by the very high rate of homologous recombination following transformation with targeting constructs (approximately 100%). Here, we describe (i) the vector design and the type of mutation that may be generated in a target locus, (ii) the selection and screening strategies that can be used to identify clones with the desired modification, and (iii) the protocol that was used for disrupting the circumsporozoite protein (CS) and thrombospondin-related anonymous protein (TRAP) genes of P. berghei.

  17. Transfusion-transmitted parasitic infections

    Directory of Open Access Journals (Sweden)

    Singh Gagandeep

    2010-01-01

    Full Text Available The transmission of parasitic organisms through transfusion is relatively rare. Of the major transfusion-transmitted diseases, malaria is a major cause of TTIP in tropical countries whereas babesiosis and Chagas′ disease pose the greatest threat to donors in the USA In both cases, this is due to the increased number of potentially infected donors. There are no reliable serologic tests available to screen donors for any of these organisms and the focus for prevention remains on adherence to donor screening guidelines that address travel history and previous infection with the etiologic agent. One goal is the development of tests that are able to screen for and identify donors potentially infectious for parasitic infections without causing the deferral of a large number of non-infectious donors or significantly increasing costs. Ideally, methods to inactivate the infectious organism will provide an element of added safety to the blood supply.

  18. PARASITE MYCOPOPULATION OF SOYBEAN GRAIN

    OpenAIRE

    Jasenka Ćosić; Karolina Vrandečić; Draženka Jurković; Ivan Ereš; Jelena Poštić

    2008-01-01

    Disease appearance on soybean can influence quality and quantity of yield. Different spieces of saprophyte and parasite fungi can be isolated from stems, pods and grain of soybean. The aim of the research was to evaluate the incidence of important disease on natural soybean grain over the period of 4 years (2004-2007) of experiment held on the location Sopot-Vinkovci and included 9 cultivars of soybean. The following plant pathogenic fungi were identified: Peronospora, Sclerotinia, Cercospora...

  19. Workshop on Cytokines and Parasites

    Science.gov (United States)

    1988-03-01

    Research Institute, Seattle, WA) demonstra- ted that GM-CSF, greater than 500 U/ml, induced the intracellular destruction of Trypanosoma cruzi by...increases the uptake of Trypanosoma cruzi by ,crophaqes, and induces a modest killing of the intracellular parasite. Dr. Gerald Byrne (University of...diseases by describing an exceedingly complex interaction of TNF and Trypanosoma musculi. TNF administered to mice early during disease actually enhanced

  20. Accumulation of persistent organic pollutants in parasites.

    Science.gov (United States)

    Yen Le, T T; Rijsdijk, Laurie; Sures, Bern; Hendriks, A Jan

    2014-08-01

    Organisms are simultaneously exposed to various stressors, including parasites and pollutants, that may interact with each other. Research on the accumulation of organic compounds in host-parasite systems is scant compared to studies on parasite-metal interactions and mainly focuses on intestinal endoparasites. We reviewed factors that determine the accumulation of persistent organic pollutants (POPs) in host-parasite systems. The wet/dry weight-based concentration of POPs in these parasites is usually lower than that in host tissues because of lower lipid contents in the parasites. However, the fractionation of the pollutants into parasites and their hosts may vary, depending on developmental stages in the life cycle of the parasites. Developmental stages determine the trophic relationship and the taxon of the parasite in the host-parasite systems because of different feeding strategies between the stages. Lipid-corrected concentrations of organic chemicals in the host are usually higher than those in the endoparasites studied. This phenomenon is attributed to a number of physiological and behavioural processes, such as feeding selectivity and strategy and excretion. Moreover, no significant relationship was found between the accumulation factor (i.e. the ratio between the lipid-corrected concentrations in parasites and in their hosts) for polychlorinated biphenyls and either hydrophobicity or molecular size. At the intermediate hydrophobicity, larger and more lipophilic compounds are accumulated at higher levels in both parasites and the host than smaller and less lipophilic compounds. The bioaccumulation of POPs in parasites is affected by some other abiotic, e.g. temperature, and biotic factors, e.g. the number of host species infected by parasites. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Gene Expression in Trypanosomatid Parasites

    Directory of Open Access Journals (Sweden)

    Santiago Martínez-Calvillo

    2010-01-01

    Full Text Available The parasites Leishmania spp., Trypanosoma brucei, and Trypanosoma cruzi are the trypanosomatid protozoa that cause the deadly human diseases leishmaniasis, African sleeping sickness, and Chagas disease, respectively. These organisms possess unique mechanisms for gene expression such as constitutive polycistronic transcription of protein-coding genes and trans-splicing. Little is known about either the DNA sequences or the proteins that are involved in the initiation and termination of transcription in trypanosomatids. In silico analyses of the genome databases of these parasites led to the identification of a small number of proteins involved in gene expression. However, functional studies have revealed that trypanosomatids have more general transcription factors than originally estimated. Many posttranslational histone modifications, histone variants, and chromatin modifying enzymes have been identified in trypanosomatids, and recent genome-wide studies showed that epigenetic regulation might play a very important role in gene expression in this group of parasites. Here, we review and comment on the most recent findings related to transcription initiation and termination in trypanosomatid protozoa.

  2. Fauna Europaea: Helminths (Animal Parasitic

    Directory of Open Access Journals (Sweden)

    David Gibson

    2014-09-01

    Full Text Available Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms of all living European land and freshwater animals, their geographical distribution at country level (up to the Urals, excluding the Caucasus region, and some additional information. The Fauna Europaea project covers about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. This represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard reference suitable for many users in science, government, industry, nature conservation and education. Helminths parasitic in animals represent a large assemblage of worms, representing three phyla, with more than 200 families and almost 4,000 species of parasites from all major vertebrate and many invertebrate groups. A general introduction is given for each of the major groups of parasitic worms, i.e. the Acanthocephala, Monogenea, Trematoda (Aspidogastrea and Digenea, Cestoda and Nematoda. Basic information for each group includes its size, host-range, distribution, morphological features, life-cycle, classification, identification and recent key-works. Tabulations include a complete list of families dealt with, the number of species in each and the name of the specialist responsible for data acquisition, a list of additional specialists who helped with particular groups, and a list of higher taxa dealt with down to the family level. A compilation of useful references is appended.

  3. Eosinophilic fasciitis after parasite infection

    Directory of Open Access Journals (Sweden)

    Marta Oliveira

    2016-03-01

    Full Text Available Eosinophilic fasciitis is a systemic inflammatory disease characterized by symmetrical swelling and skin induration of the distal portions of the arms and/or legs, evolving into a scleroderma-like appearance, accompanied by peripheral blood eosinophilia. It is a rare disease with a poorly understood etiology. Corticosteroid treatment remains the standard therapy, either taken alone or in association with an immunosuppressive drug. This paper presents a case of a male patient with palpebral edema and marked eosinophilia, diagnosed with intestinal parasitic infection in October 2006. He was treated with an antiparasitic drug, but both the swelling and the analytical changes remained. This was followed by a skin and muscle biopsy, which turned out to be compatible with eosinophilic fasciitis. There was progressive worsening of the clinical state, with stiffness of the abdominal wall and elevated inflammatory parameters, and the patient was referred to the Immunology Department, medicated with corticosteroids and methotrexate. Over the years there were therapeutic adjustments and other causes were excluded. Currently the patient continues to be monitored, and there is no evidence of active disease. The case described in this article is interesting because of the diagnosis of eosinophilic fasciitis probably associated/coexisting with a parasite infection. This case report differs from others in that there is an uncommon cause associated with the onset of the disease, instead of the common causes such as trauma, medication, non-parasitic infections or cancer.

  4. Eosinophilic fasciitis after parasite infection.

    Science.gov (United States)

    Oliveira, Marta; Patinha, Fabia; Marinho, Antonio

    2016-01-01

    Eosinophilic fasciitis is a systemic inflammatory disease characterized by symmetrical swelling and skin induration of the distal portions of the arms and/or legs, evolving into a scleroderma-like appearance, accompanied by peripheral blood eosinophilia. It is a rare disease with a poorly understood etiology. Corticosteroid treatment remains the standard therapy, either taken alone or in association with an immunosuppressive drug. This paper presents a case of a male patient with palpebral edema and marked eosinophilia, diagnosed with intestinal parasitic infection in October 2006. He was treated with an antiparasitic drug, but both the swelling and the analytical changes remained. This was followed by a skin and muscle biopsy, which turned out to be compatible with eosinophilic fasciitis. There was progressive worsening of the clinical state, with stiffness of the abdominal wall and elevated inflammatory parameters, and the patient was referred to the Immunology Department, medicated with corticosteroids and methotrexate. Over the years there were therapeutic adjustments and other causes were excluded. Currently the patient continues to be monitored, and there is no evidence of active disease. The case described in this article is interesting because of the diagnosis of eosinophilic fasciitis probably associated/coexisting with a parasite infection. This case report differs from others in that there is an uncommon cause associated with the onset of the disease, instead of the common causes such as trauma, medication, non-parasitic infections or cancer.

  5. 1H NMR metabonomics indicates continued metabolic changes and sexual dimorphism post-parasite clearance in self-limiting murine malaria model.

    Directory of Open Access Journals (Sweden)

    Arjun Sengupta

    Full Text Available Malaria, a mosquito-borne disease caused by Plasmodium spp. is considered to be a global threat, specifically for the developing countries. In human subjects considerable information exists regarding post-malarial physiology. However, most murine malarial models are lethal, and most studies deal with acute phases occurring as disease progresses. Much less is known regarding physiological status post-parasite clearance. We have assessed the physiological changes at the organ levels using (1H NMR based metabonomics in a non lethal self-clearing murine malarial model of P. chabaudi parasites and Balb/C, far beyond the parasite clearance point. The results showed distinct metabolic states between uninfected and infected mice at the peak parasitemia, as well as three weeks post-parasite clearance. Our data also suggests that the response at the peak infection as well as recovery exhibited distinct sexual dimorphism. Specifically, we observed accumulation of acetylcholine in the brain metabolic profile of both the sexes. This might have important implication in understanding the pathophysiology of the post malarial neurological syndromes. In addition, the female liver showed high levels of glucose, dimethylglycine, methylacetoacetate and histidine after three weeks post-parasite clearance, while the males showed accumulation of branched chain amino acids, lysine, glutamine and bile acids.

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

    Science.gov (United States)

    Thieltges, David W.; Amundsen, Per-Arne; Hechinger, Ryan F.; Johnson, Pieter T.J.; Lafferty, Levin D.; Mouritsen, Kim N.; Preston, Daniel L.; Reise, Karsten; Zander, C. Dieter; Poulin, Robert

    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 parasite transmission in eight topological food webs representing marine and freshwater ecosystems. Within each food web, we examined links in the typical predator–prey sub web as well as the predator–parasite sub web, i.e. the quadrant of the food web indicating which predators eat parasites. Most predator– parasite links represented ‘concomitant predation’ (consumption and death of a parasite along with the prey/host; 58–72%), followed by ‘trophic transmission’ (predator feeds on infected prey and becomes infected; 8–32%) and predation on free-living parasite life-cycle stages (4–30%). Parasite life-cycle stages had, on average, between 4.2 and 14.2 predators. Among the food webs, as predator richness increased, the number of links exploited by trophically transmitted parasites increased at about the same rate as did the number of links where these stages serve as prey. On the whole, our analyses suggest that predation on parasites has important consequences for both predators and parasites, and food web structure. Because our analysis is solely based on topological webs, determining the strength of these interactions is a promising avenue for future research.

  7. Evolution of apoptosis-like programmed cell death in unicellular protozoan parasites.

    Science.gov (United States)

    Kaczanowski, Szymon; Sajid, Mohammed; Reece, Sarah E

    2011-03-25

    Apoptosis-like programmed cell death (PCD) has recently been described in multiple taxa of unicellular protists, including the protozoan parasites Plasmodium, Trypanosoma and Leishmania. Apoptosis-like PCD in protozoan parasites shares a number of morphological features with programmed cell death in multicellular organisms. However, both the evolutionary explanations and mechanisms involved in parasite PCD are poorly understood. Explaining why unicellular organisms appear to undergo 'suicide' is a challenge for evolutionary biology and uncovering death executors and pathways is a challenge for molecular and cell biology. Bioinformatics has the potential to integrate these approaches by revealing homologies in the PCD machinery of diverse taxa and evaluating their evolutionary trajectories. As the molecular mechanisms of apoptosis in model organisms are well characterised, and recent data suggest similar mechanisms operate in protozoan parasites, key questions can now be addressed. These questions include: which elements of apoptosis machinery appear to be shared between protozoan parasites and multicellular taxa and, have these mechanisms arisen through convergent or divergent evolution? We use bioinformatics to address these questions and our analyses suggest that apoptosis mechanisms in protozoan parasites and other taxa have diverged during their evolution, that some apoptosis factors are shared across taxa whilst others have been replaced by proteins with similar biochemical activities.

  8. A few good reasons why species-area relationships do not work for parasites.

    Science.gov (United States)

    Strona, Giovanni; Fattorini, Simone

    2014-01-01

    Several studies failed to find strong relationships between the biological and ecological features of a host and the number of parasite species it harbours. In particular, host body size and geographical range are generally only weak predictors of parasite species richness, especially when host phylogeny and sampling effort are taken into account. These results, however, have been recently challenged by a meta-analytic study that suggested a prominent role of host body size and range extent in determining parasite species richness (species-area relationships). Here we argue that, in general, results from meta-analyses should not discourage researchers from investigating the reasons for the lack of clear patterns, thus proposing a few tentative explanations to the fact that species-area relationships are infrequent or at least difficult to be detected in most host-parasite systems. The peculiar structure of host-parasite networks, the enemy release hypothesis, the possible discrepancy between host and parasite ranges, and the evolutionary tendency of parasites towards specialization may explain why the observed patterns often do not fit those predicted by species-area relationships.

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

    Directory of Open Access Journals (Sweden)

    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.

  10. Investigating the evolution of apoptosis in malaria parasites: the importance of ecology

    Directory of Open Access Journals (Sweden)

    Pollitt Laura C

    2010-11-01

    Full Text Available Abstract Apoptosis is a precisely regulated process of cell death which occurs widely in multicellular organisms and is essential for normal development and immune defences. In recent years, interest has grown in the occurrence of apoptosis in unicellular organisms. In particular, as apoptosis has been reported in a wide range of species, including protozoan malaria parasites and trypanosomes, it may provide a novel target for intervention. However, it is important to understand when and why parasites employ an apoptosis strategy before the likely long- and short-term success of such an intervention can be evaluated. The occurrence of apoptosis in unicellular parasites provides a challenge for evolutionary theory to explain as organisms are expected to have evolved to maximise their own proliferation, not death. One possible explanation is that protozoan parasites undergo apoptosis in order to gain a group benefit from controlling their density as this prevents premature vector mortality. However, experimental manipulations to examine the ultimate causes behind apoptosis in parasites are lacking. In this review, we focus on malaria parasites to outline how an evolutionary framework can help make predictions about the ecological circumstances under which apoptosis could evolve. We then highlight the ecological considerations that should be taken into account when designing evolutionary experiments involving markers of cell death, and we call for collaboration between researchers in different fields to identify and develop appropriate markers in reference to parasite ecology and to resolve debates on terminology.

  11. Joint Non-Lethal Weapons Program Science and Technology Strategic Plan

    Science.gov (United States)

    2016-03-31

    3 United Nations, World Urbanization Prospects: The 2014 Revision, 13  4 David Shunk, “ Mega   Cities , Ungoverned Areas, and the Challenge of Army...Urban Combat Operations in 2030‐ 2040,” Small Wars Journal, 23 Jan 2014, http://smallwarsjournal.com/jrnl/art/ mega ‐ cities ‐ungoverned‐areas‐and‐ the...Joint Non‐Lethal Weapons Program Science and Technology Strategic  Plan        I  On the Cover  Carbon Nanotubes  Promising ultra‐light weight and

  12. Protective monotherapy against lethal Ebola virus infection by a potently neutralizing antibody.

    Science.gov (United States)

    Corti, Davide; Misasi, John; Mulangu, Sabue; Stanley, Daphne A; Kanekiyo, Masaru; Wollen, Suzanne; Ploquin, Aurélie; Doria-Rose, Nicole A; Staupe, Ryan P; Bailey, Michael; Shi, Wei; Choe, Misook; Marcus, Hadar; Thompson, Emily A; Cagigi, Alberto; Silacci, Chiara; Fernandez-Rodriguez, Blanca; Perez, Laurent; Sallusto, Federica; Vanzetta, Fabrizia; Agatic, Gloria; Cameroni, Elisabetta; Kisalu, Neville; Gordon, Ingelise; Ledgerwood, Julie E; Mascola, John R; Graham, Barney S; Muyembe-Tamfun, Jean-Jacques; Trefry, John C; Lanzavecchia, Antonio; Sullivan, Nancy J

    2016-03-18

    Ebola virus disease in humans is highly lethal, with case fatality rates ranging from 25 to 90%. There is no licensed treatment or vaccine against the virus, underscoring the need for efficacious countermeasures. We ascertained that a human survivor of the 1995 Kikwit Ebola virus disease outbreak maintained circulating antibodies against the Ebola virus surface glycoprotein for more than a decade after infection. From this survivor we isolated monoclonal antibodies (mAbs) that neutralize recent and previous outbreak variants of Ebola virus and mediate antibody-dependent cell-mediated cytotoxicity in vitro. Strikingly, monotherapy with mAb114 protected macaques when given as late as 5 days after challenge. Treatment with a single human mAb suggests that a simplified therapeutic strategy for human Ebola infection may be possible.

  13. Antibody to the E3 Glycoprotein Protects Mice against Lethal Venezuelan Equine Encephalitis Virus Infection▿

    Science.gov (United States)

    Parker, Michael D.; Buckley, Marilyn J.; Melanson, Vanessa R.; Glass, Pamela J.; Norwood, David; Hart, Mary Kate

    2010-01-01

    Six monoclonal antibodies were isolated that exhibited specificity for a furin cleavage site deletion mutant (V3526) of Venezuelan equine encephalitis virus (VEEV). These antibodies comprise a single competition group and bound the E3 glycoprotein of VEEV subtype I viruses but failed to bind the E3 glycoprotein of other alphaviruses. These antibodies neutralized V3526 virus infectivity but did not neutralize the parental strain of Trinidad donkey (TrD) VEEV. However, the E3-specific antibodies did inhibit the production of virus from VEEV TrD-infected cells. In addition, passive immunization of mice demonstrated that antibody to the E3 glycoprotein provided protection against lethal VEEV TrD challenge. This is the first recognition of a protective epitope in the E3 glycoprotein. Furthermore, these results indicate that E3 plays a critical role late in the morphogenesis of progeny virus after E3 appears on the surfaces of infected cells. PMID:20926570

  14. Immune Serum Produced by DNA Vaccination Protects Hamsters against Lethal Respiratory Challenge with Andes Virus

    Science.gov (United States)

    2008-02-01

    pulmonary syndrome in Argentina. Possibility of person to person transmission. Medicina (Buenos Aires) 56: 709–711. 8. Ferres, M., P. Vial, C. Marco, L...transmission of Andes virus. Medicina (Buenos Aires) 58(Suppl. 1):27–36. 20. Padula, P. J., A. Edelstein, S. D. Miguel, N. M. Lopez, C. M. Rossi, and R

  15. Inactivated recombinant plant virus protects dogs from a lethal challenge with canine parvovirus

    DEFF Research Database (Denmark)

    Langeveld, J.P.M.; Brennan, F.R.; Martinez-Torrecuadrada, J.L.

    2001-01-01

    A vaccine based upon a recombinant plant virus (CPMV-PARVO1), displaying a peptide derived from the VP2 capsid protein of canine parvovirus (CPV), has previously been described. To date, studies with the vaccine have utilized viable plant chimaeric particles (CVPs). In this study, CPMV-PARVO1...

  16. Galantamine is a Novel Post-Exposure Therapeutic Against Lethal VX Challenge

    Science.gov (United States)

    2009-01-01

    Galantamine prevents apoptosis induced by β-amyloid and thapsigargin: involvement of nicotinic acetylcholine receptors. Neuropharmacology 46, 103–114...1173. Corey-Bloom, J., 2003. Galantamine: a review of its use in Alzheimer’s disease and vascular dementia . Int. J. Clin. Pract. 57, 219–223. Dawson...129. Kihara, T., Sawada, H., Nakamizo, T., Kanki, R., Yamashita, H., Maelicke, A., Shimohama, S., 2004. Galantamine modulates nicotinic receptor and

  17. 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.

  18. An improved brine shrimp larvae lethality microwell test method.

    Science.gov (United States)

    Zhang, Yi; Mu, Jun; Han, Jinyuan; Gu, Xiaojie

    2012-01-01

    This article described an improved brine shrimp larvae lethality microwell test method. A simply designed connecting vessel with alternative photoperiod was used to culture and collect high yield of active Artemia parthenogenetica nauplii for brine shrimp larvae lethality microwell test. Using this method, pure A. parthenogenetica nauplii suspension was easily cultured and harvested with high density about 100-150 larvae per milliliter and the natural mortality was reduced to near zero by elimination of unnecessary artificial disturbance. And its sensitivity was validated by determination of LC(50)-24 h of different reference toxicants including five antitumor agents, two pesticides, three organic pollutants, and four heavy metals salts, most of which exhibited LC(50)-24 h between 0.07 and 58.43 mg/L except for bleomycin and mitomycin C with LC(50)-24 h over 300 mg/L.

  19. Neonatal lethal dwarfism with distinct skeletal malformations - a separate entity?

    Energy Technology Data Exchange (ETDEWEB)

    Rosendahl, K.; Maurseth, K.; Olsen, Oe.E. [Dept. of Paediatric Radiology, Haukeland University Hospital, Bergen (Norway); Halvorsen, O.J. [Dept. of Pathology, Haukeland University Hospital, Bergen (Norway); Gjelland, K. [Dept. of Gynaecology, Haukeland University Hospital, Bergen (Norway); Engebretsen, L. [Dept. of Genetics, Haukeland University Hospital, Bergen (Norway)

    2001-09-01

    We describe a case of neonatal lethal dwarfism characterised by short trunk, short, stick-like tubular bones, deficient ossification of the axial skeleton and broad, sclerotic horizontal ribs. Two similar cases have previously been reported as examples of the Neu-Laxova syndrome. However, the radiological findings of the Neu-Laxova syndrome, as reported in 16 out of 40 documented cases, show a heterogeneous pattern of minor features, which differ distinctively from those found in the previous two cases and by us. A literature research did not reveal similar cases, and we therefore suggest that our case, together with the two previous cases, may represent a new distinctive form of neonatal lethal dwarfism. (orig.)

  20. Synthetic lethality between PAXX and XLF in mammalian development

    Science.gov (United States)

    Balmus, Gabriel; Barros, Ana C.; Wijnhoven, Paul W.G.; Lescale, Chloé; Hasse, Hélène Lenden; Boroviak, Katharina; le Sage, Carlos; Doe, Brendan; Speak, Anneliese O.; Galli, Antonella; Jacobsen, Matt; Deriano, Ludovic; Adams, David J.; Jackson, Stephen P.

    2016-01-01

    PAXX was identified recently as a novel nonhomologous end-joining DNA repair factor in human cells. To characterize its physiological roles, we generated Paxx-deficient mice. Like Xlf−/− mice, Paxx−/− mice are viable, grow normally, and are fertile but show mild radiosensitivity. Strikingly, while Paxx loss is epistatic with Ku80, Lig4, and Atm deficiency, Paxx/Xlf double-knockout mice display embryonic lethality associated with genomic instability, cell death in the central nervous system, and an almost complete block in lymphogenesis, phenotypes that closely resemble those of Xrcc4−/− and Lig4−/− mice. Thus, combined loss of Paxx and Xlf is synthetic-lethal in mammals. PMID:27798842

  1. Collateral Lethality: A new therapeutic strategy in oncology.

    Science.gov (United States)

    Muller, Florian L; Aquilanti, Elisa A; DePinho, Ronald A

    2015-11-01

    Genomic deletion of tumor suppressor genes (TSG) is a rite of passage for virtually all human cancers. The synthetic lethal paradigm has provided a framework for the development of molecular targeted therapeutics that are functionally linked to the loss of specific TSG functions. In the course of genomic events that delete TSGs, a large number of genes with no apparent direct role in tumor promotion also sustain deletion as a result of chromosomal proximity to the target TSG. In this perspective, we review the novel concept of "collateral lethality", which has served to identify cancer-specific therapeutic vulnerabilities resulting from co-deletion of passenger genes neighboring TSG. The large number of collaterally deleted genes, playing diverse functions in cell homeostasis, offers a rich repertoire of pharmacologically targetable vulnerabilities presenting novel opportunities for the development of personalized anti-neoplastic therapies.

  2. Parasitic aphrodisiacs: manipulation of the hosts' behavioral defenses by sexually transmitted parasites.

    Science.gov (United States)

    Adamo, Shelley A

    2014-07-01

    Animals have a number of behavioral defenses against infection. For example, they typically avoid sick conspecifics, especially during mating. Most animals also alter their behavior after infection and thereby promote recovery (i.e., sickness behavior). For example, sick animals typically reduce the performance of energetically demanding behaviors, such as sexual behavior. Finally, some animals can increase their reproductive output when they face a life-threatening immune challenge (i.e., terminal reproductive investment). All of these behavioral responses probably rely on immune/neural communication signals for their initiation. Unfortunately, this communication channel is prone to manipulation by parasites. In the case of sexually transmitted infections (STIs), these parasites/pathogens must subvert some of these behavioral defenses for successful transmission. There is evidence that STIs suppress systemic signals of immune activation (e.g., pro-inflammatory cytokines). This manipulation is probably important for the suppression of sickness behavior and other behavioral defenses, as well as for the prevention of attack by the host's immune system. For example, the cricket, Gryllus texensis, is infected with an STI, the iridovirus IIV-6/CrIV. The virus attacks the immune system, which suffers a dramatic decline in its ability to make proteins important for immune function. This attack also hampers the ability of the immune system to activate sickness behavior. Infected crickets cannot express sickness behavior, even when challenged with heat-killed bacteria. Understanding how STIs suppress sickness behavior in humans and other animals will significantly advance the field of psychoneuroimmunology and could also provide practical benefits.

  3. Multidisciplinary studies, systems approaches and parasite eco-epidemiology: something old, something new.

    Science.gov (United States)

    Giraudoux, P; Raoul, F; Pleydell, D; Craig, P S

    2008-09-01

    Parasite requires an understanding of complex transmission systems where individual, population and environmental factors and their interactions can hardly been considered separately. Moreover, the importance of space and time in host population and parasite transmission processes is increasingly recognised. The present review illustrates how epidemiology and transmission ecology have evolved in a multidisciplinary framework to a systems approach that includes both spatial and temporal dimensions. Focusing on population processes, three significant challenges are discussed: (i) integration of landscape ecology concepts and modelling across time-space scales, (ii) development of molecular methods that permits easy parasite/host identification and process tracking (e.g. host and parasite movements), and (iii) integration of sociology methods to estimate zoonotic risk and exposure.

  4. Multidisciplinary studies, systems approaches and parasite eco-epidemiology: something old, something new

    Directory of Open Access Journals (Sweden)

    Giraudoux P.

    2008-09-01

    Full Text Available Parasite requires an understanding of complex transmission systems where individual, population and environmental factors and their interactions can hardly been considered separately. Moreover, the importance of space and time in host population and parasite transmission processes is increasingly recognised. The present review illustrates how epidemiology and transmission ecology have evolved in a multidisciplinary framework to a systems approach that includes both spatial and temporal dimensions. Focusing on population processes, three significant challenges are discussed: (i integration of landscape ecology concepts and modelling across time-space scales, (ii development of molecular methods that permits easy parasite/host identification and process tracking (e.g. host and parasite movements, and (iii integration of sociology methods to estimate zoonotic risk and exposure.

  5. Imaging and identification of waterborne parasites using a chip-scale microscope.

    Directory of Open Access Journals (Sweden)

    Seung Ah Lee

    Full Text Available We demonstrate a compact portable imaging system for the detection of waterborne parasites in resource-limited settings. The previously demonstrated sub-pixel sweeping microscopy (SPSM technique is a lens-less imaging scheme that can achieve high-resolution (<1 µm bright-field imaging over a large field-of-view (5.7 mm×4.3 mm. A chip-scale microscope system, based on the SPSM technique, can be used for automated and high-throughput imaging of protozoan parasite cysts for the effective diagnosis of waterborne enteric parasite infection. We successfully imaged and identified three major types of enteric parasite cysts, Giardia, Cryptosporidium, and Entamoeba, which can be found in fecal samples from infected patients. We believe that this compact imaging system can serve well as a diagnostic device in challenging environments, such as rural settings or emergency outbreaks.

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

    DEFF Research Database (Denmark)

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

    -control options are required. We present results from a comprehensive in vitro screen of plant secondary metabolites (PSM) from diverse plant sources on the economically important pig parasites Ascaris chlamydiae and Oesophagostomum dentatum . We focused on two PSM classes commonly found in natural diets......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...... – condensed tannins (CT) and sesquiterpene lactones (SL). Different CT-types were purified from various plant sources to reflect their diversity; SL were purified from forage chicory. These PSM were tested in inhibition assays of worm motility and migratory ability. CT had potent activity against A. suum...

  7. Parasitic diseases of the central nervous system: lessons for clinicians and policy makers.

    Science.gov (United States)

    Carpio, Arturo; Romo, Matthew L; Parkhouse, R M E; Short, Brooke; Dua, Tarun

    2016-01-01

    Parasitic diseases of the central nervous system are associated with high mortality and morbidity, especially in resource-limited settings. The burden of these diseases is amplified as survivors are often left with neurologic sequelae affecting mobility, sensory organs, and cognitive functions, as well as seizures/epilepsy. These diseases inflict suffering by causing lifelong disabilities, reducing economic productivity, and causing social stigma. The complexity of parasitic life cycles and geographic specificities, as well as overlapping clinical manifestations in the host reflecting the diverse pathogenesis of parasites, can present diagnostic challenges. We herein provide an overview of these parasitic diseases and summarize clinical aspects, diagnosis, therapeutic strategies and recent milestones, and aspects related to prevention and control.

  8. Anthrax vaccination induced anti-lethal factor IgG: fine specificity and neutralizing capacity.

    Science.gov (United States)

    Crowe, Sherry R; Garman, Lori; Engler, Renata J M; Farris, A Darise; Ballard, Jimmy D; Harley, John B; James, Judith A

    2011-05-09

    The efficacy biomarker of the currently licensed anthrax vaccine (AVA) is based on quantity and neutralizing capacity of anti-protective antigen (anti-PA) antibodies. However, animal studies have demonstrated that antibodies to lethal factor (LF) can provide protection against in vivo bacterial spore challenges. Improved understanding of the fine specificities of humoral immune responses that provide optimum neutralization capacity may enhance the efficacy of future passive immune globulin preparations to treat and prevent inhalation anthrax morbidity and mortality. This study (n=1000) was designed to identify AVA vaccinated individuals who generate neutralizing antibodies and to determine what specificities correlate with protection. The number of vaccine doses, years post vaccination, and PA titer were associated with in vitro neutralization, reinforcing previous reports. In addition, African American individuals had lower serologic neutralizing activity than European Americans, suggesting a genetic role in the generation of these neutralizing antibodies. Of the vaccinated individuals, only 69 (6.9%) had moderate levels of anti-LF IgG compared to 244 (24.4%) with low and 687 (68.7%) with extremely low levels of IgG antibodies to LF. Using overlapping decapeptide analysis, we identified six common LF antigenic regions targeted by those individuals with moderate levels of antibodies to LF and high in vitro toxin neutralizing activity. Affinity purified antibodies directed against antigenic epitopes within the PA binding and ADP-ribotransferase-like domains of LF were able to protect mice against lethal toxin challenge. Findings from these studies have important implications for vaccine design and immunotherapeutic development.

  9. An Antivector Vaccine Protects against a Lethal Vector-Borne Pathogen.

    Directory of Open Access Journals (Sweden)

    2006-04-01

    Full Text Available Vaccines that target blood-feeding disease vectors, such as mosquitoes and ticks, have the potential to protect against the many diseases caused by vector-borne pathogens. We tested the ability of an anti-tick vaccine derived from a tick cement protein (64TRP of Rhipicephalus appendiculatus to protect mice against tick-borne encephalitis virus (TBEV transmitted by infected Ixodes ricinus ticks. The vaccine has a "dual action" in immunized animals: when infested with ticks, the inflammatory and immune responses first disrupt the skin feeding site, resulting in impaired blood feeding, and then specific anti-64TRP antibodies cross-react with midgut antigenic epitopes, causing rupture of the tick midgut and death of engorged ticks. Three parameters were measured: "transmission," number of uninfected nymphal ticks that became infected when cofeeding with an infected adult female tick; "support," number of mice supporting virus transmission from the infected tick to cofeeding uninfected nymphs; and "survival," number of mice that survived infection by tick bite and subsequent challenge by intraperitoneal inoculation of a lethal dose of TBEV. We show that one dose of the 64TRP vaccine protects mice against lethal challenge by infected ticks; control animals developed a fatal viral encephalitis. The protective effect of the 64TRP vaccine was comparable to that of a single dose of a commercial TBEV vaccine, while the transmission-blocking effect of 64TRP was better than that of the antiviral vaccine in reducing the number of animals supporting virus transmission. By contrast, the commercial antitick vaccine (TickGARD that targets only the tick's midgut showed transmission-blocking activity but was not protective. The 64TRP vaccine demonstrates the potential to control vector-borne disease by interfering with pathogen transmission, apparently by mediating a local cutaneous inflammatory immune response at the tick-feeding site.

  10. An antivector vaccine protects against a lethal vector-borne pathogen.

    Directory of Open Access Journals (Sweden)

    Milan Labuda

    2006-04-01

    Full Text Available Vaccines that target blood-feeding disease vectors, such as mosquitoes and ticks, have the potential to protect against the many diseases caused by vector-borne pathogens. We tested the ability of an anti-tick vaccine derived from a tick cement protein (64TRP of Rhipicephalus appendiculatus to protect mice against tick-borne encephalitis virus (TBEV transmitted by infected Ixodes ricinus ticks. The vaccine has a "dual action" in immunized animals: when infested with ticks, the inflammatory and immune responses first disrupt the skin feeding site, resulting in impaired blood feeding, and then specific anti-64TRP antibodies cross-react with midgut antigenic epitopes, causing rupture of the tick midgut and death of engorged ticks. Three parameters were measured: "transmission," number of uninfected nymphal ticks that became infected when cofeeding with an infected adult female tick; "support," number of mice supporting virus transmission from the infected tick to cofeeding uninfected nymphs; and "survival," number of mice that survived infection by tick bite and subsequent challenge by intraperitoneal inoculation of a lethal dose of TBEV. We show that one dose of the 64TRP vaccine protects mice against lethal challenge by infected ticks; control animals developed a fatal viral encephalitis. The protective effect of the 64TRP vaccine was comparable to that of a single dose of a commercial TBEV vaccine, while the transmission-blocking effect of 64TRP was better than that of the antiviral vaccine in reducing the number of animals supporting virus transmission. By contrast, the commercial antitick vaccine (TickGARD that targets only the tick's midgut showed transmission-blocking activity but was not protective. The 64TRP vaccine demonstrates the potential to control vector-borne disease by interfering with pathogen transmission, apparently by mediating a local cutaneous inflammatory immune response at the tick-feeding site.

  11. 28 CFR 552.25 - Use of chemical agents or non-lethal weapons.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Use of chemical agents or non-lethal weapons. 552.25 Section 552.25 Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF JUSTICE... agents or non-lethal weapons. The Warden may authorize the use of chemical agents or non-lethal weapons...

  12. Meckel-Gruber syndrome: A rare and lethal anomaly

    OpenAIRE

    Kheir, Abdelmoneim E.M.; Imam, Abdelmutalab; Omer, Ilham M.; Hassan, Ibtsama M.A.; Elamin, Sara A.; Awadalla, Esra A.; Gadalla, Mohammed H.; Hamdoon, Tagwa A.

    2012-01-01

    Meckel-Gruber syndrome is a rare and lethal autosomal recessive disorder characterized by occipital encephalocele, postaxial polydactyly and bilateral dysplastic cystic kidneys. It can be associated with many other conditions. Antenatal ultrasound examination establishes the diagnosis by identifying at least two of the major features described. We describe a female baby who had the typical triad of Meckel-Gruber syndrome and died shortly after birth.

  13. Merging Hyperspectural Imagery and Multi Scale Modeling for Laser Lethality

    Science.gov (United States)

    2016-02-24

    field, to be submitted Combustion Theory and Modeling, 2016. Changes in research objectives (if any): Change in AFOSR Program Manager, if any...Extensions granted or milestones slipped, if any: AFOSR LRIR Number LRIR Title Reporting Period Laboratory Task Manager Program Officer Research Objectives ...AFRL-AFOSR-VA-TR-2016-0088 MERGING HYPERSPECTRAL IMAGERY AND MULTI -SCALE MODELING FOR LASER LETHALITY Leonid Zhigilei UNIVERSITY OF VIRGINIA Final

  14. [Lethal intravenous infusion of a wound antiseptic containing polyhexanide].

    Science.gov (United States)

    Wehner, Frank; Wehner, Heinz-Dieter; Schulz, Martin Manfred

    2009-01-01

    Polyhexamethylene biguanide (PHMB) is considered to be highly histocompatible and is one of the most frequently used wound antiseptics. Only one case of intoxication has been reported so far. The present case of a lethal intoxication is the first fatal incident described where causality is substantiated by a temporal coincidence between application and ascertainable organ damage. The laboratory-chemical and histological investigations verified the toxicity of this substance after intravenous application with the main findings being severe hepatic and pancreatic damage.

  15. Meckel-Gruber syndrome: A rare and lethal anomaly.

    Science.gov (United States)

    Kheir, Abdelmoneim E M; Imam, Abdelmutalab; Omer, Ilham M; Hassan, Ibtsama M A; Elamin, Sara A; Awadalla, Esra A; Gadalla, Mohammed H; Hamdoon, Tagwa A

    2012-01-01

    Meckel-Gruber syndrome is a rare and lethal autosomal recessive disorder characterized by occipital encephalocele, postaxial polydactyly and bilateral dysplastic cystic kidneys. It can be associated with many other conditions. Antenatal ultrasound examination establishes the diagnosis by identifying at least two of the major features described. We describe a female baby who had the typical triad of Meckel-Gruber syndrome and died shortly after birth.

  16. A lethal syndrome resembling branchio-oculo-facial syndrome.

    Science.gov (United States)

    Hing, A V; Torack, R; Dowton, S B

    1992-02-01

    Branchio-oculo-facial syndrome, a recently delineated autosomal dominant condition, is characterized by branchial cleft sinuses, ocular anomalies, and unusual facial appearance. A patient with branchial cleft fistulae, microphthalmia, nasomaxillary dysplasia, in addition to cardiac and CNS malformation (holoprosencephaly and meningo-encephalocele), is described. Although many features of this lethal malformation complex resemble those seen in the branchio-oculo-facial syndrome, the complex may represent a new multiple malformation syndrome.

  17. The characteristic of lethality as an indicator of combinad infections

    Directory of Open Access Journals (Sweden)

    V. V. Nechaev

    2016-01-01

    Full Text Available The Combined Socially Important Infections (CSII in St. Petersburg are result of accumulation of chroniogenic potential of HIV infection, tuberculosis and chronic viral hepatitis B and C. The analysis of a lethality from the combined infection (CI for the long-term period in dynamics by years, showed to age and sexual groups and other signs that it exceeds that from tuberculosis by 2,4 times, from chronic hepatitis by 7,5 times. High level of a lethality of persons of young age, sharp growth of tuberculosis of intra chest, intra belly lymph nodes, frequent generalization of process with involvement in process of a liver, a spleen, kidneys testifies to the leading role of HIV infection in failures of diseases. The system and algorithm of proofs about the reasons of lethal outcomes of SI have to be based on representative selections. For this purpose it is necessary to carry out registration of HIV infection not only in the AIDS centers, but also regional in the form of the uniform register SI (HIV+TB+HIC or HIB for the purpose of complex impact on epidemic process.

  18. Mouse model of sublethal and lethal intraperitoneal glanders (Burkholderia mallei).

    Science.gov (United States)

    Fritz, D L; Vogel, P; Brown, D R; Deshazer, D; Waag, D M

    2000-11-01

    Sixty male BALB/c mice were inoculated intraperitoneally with either a sublethal or a lethal dose of Burkholderia mallei China 7 strain, then killed at multiple time points postinoculation. Histopathologic changes were qualitatively similar in both groups and consisted of pyogranulomatous inflammation. In sublethal study mice, changes were first seen at 6 hours in mediastinal lymph nodes, then in spleen, liver, peripheral lymph nodes, and bone marrow at day 3. These changes generally reached maximal incidence and severity by day 4 but decreased by comparison in all tissues except the liver. Changes were first seen in lethal study mice also at 6 hours in mediastinal lymph nodes and in spleens. At day 1, changes were present in liver, peripheral lymph nodes, and bone marrow. The incidence and severity of these changes were maximal at day 2. In contrast to sublethal study mice, the incidence and severity of the changes did not decrease through the remainder of the study. The most significant difference between the two groups was the rapid involvement of the spleen in the lethal study mice. Changes indicative of impaired vascular perfusion were more frequently seen in the sublethal study mice. Our findings indicate that mice are susceptible to B. mallei infection and may serve as an appropriate model for glanders infection in a resistant host such as human beings. Additionally, by immunoelectron microscopy, we showed the presence of type I O-antigenic polysaccharide (capsular) antigen surrounding B. mallei.

  19. Canine and feline parasitic zoonoses in China

    Directory of Open Access Journals (Sweden)

    Chen Jia

    2012-07-01

    Full Text Available Abstract Canine and feline parasitic zoonoses have not been given high priority in China, although the role of companion animals as reservoirs for zoonotic parasitic diseases has been recognized worldwide. With an increasing number of dogs and cats under unregulated conditions in China, the canine and feline parasitic zoonoses are showing a trend towards being gradually uncontrolled. Currently, canine and feline parasitic zoonoses threaten human health, and cause death and serious diseases in China. This article comprehensively reviews the current status of major canine and feline parasitic zoonoses in mainland China, discusses the risks dogs and cats pose with regard to zoonotic transmission of canine and feline parasites, and proposes control strategies and measures.

  20. Control and prevention of emerging parasitic zoonoses.

    Science.gov (United States)

    Chomel, Bruno B

    2008-09-01

    Emerging zoonoses have been defined as zoonoses that are newly recognised or newly evolved, or that have occurred previously but show an increase in incidence or expansion in geographical, host or vector range. Among parasitic zoonoses, protozoa are particularly likely to emerge. Control and prevention of emerging parasitic zoonoses are complex tasks that require an integrative and multidisciplinary approach. Reduction of parasite burden is certainly a major objective but cannot be set alone. Therefore, environmental and ecological modifications need to be implemented to reduce not only the parasitic load, but also the risk of parasite transmission. Finally, education and behavioral changes are critical for the success of both control and prevention of these diseases. However, without appropriate financial resources specifically allocated at the local and national levels as well as through international cooperation, control and prevention of these emerging parasitic diseases will not be possible.

  1. The evolution of parasitism in plants.

    Science.gov (United States)

    Westwood, James H; Yoder, John I; Timko, Michael P; dePamphilis, Claude W

    2010-04-01

    The multiple independent origins of plant parasitism suggest that numerous ancestral plant lineages possessed the developmental flexibility to meet the requirements of a parasitic life style, including such adaptations as the ability to recognize host plants, form an invasive haustorium, and regulate the transfer of nutrients and other molecules between two different plants. In this review, we focus on the Orobanchaceae, which are unique among the parasitic plants in that extant member species include the full range of host dependence from facultative to obligate parasites. The recent emergence of genomic resources for these plants should provide new insights into parasitic plant evolution and enable the development of novel genetic strategies for controlling parasitic weeds.

  2. PARASITES INFECTIONS OF GOLDFISH (Carassius auratus L.

    Directory of Open Access Journals (Sweden)

    Emil Gjurčević

    2006-01-01

    Full Text Available Removing fish from their natural environment, and placing them in aquariums, where large number is concentrated on small space, causes not only stress but increases the possibility of disease. In these unnatural conditions but often adequate for parasite reproduction, parasites can cause diseases leading to death. In our work we investigated parasites presence in goldfish (Carassius auratus L. kept in aquarium, from three different pet shops. The study showed presence of: Trypanoplasma sp., Trichodina sp., Ichthyophthirius multifiliis, Myxoboulus sp., Dactylogyrus sp. and Gyrodactylus sp. Considering the number of parasites found in examined fish, it can be possible that parasites can cause mortality in goldfish. Therefore, special caution has to be on quarantine and healthcare while importing especially exotic aquarium fish that may be infected with exotic parasites. In case of disease, proper treatment in due time has to be conducted.

  3. Parasitic diseases in the abdomen: imaging findings.

    Science.gov (United States)

    Lim, Jae Hoon

    2008-01-01

    Parasitic diseases of the liver and biliary tract include echinococcosis, schistosomiasis, toxocariasis, clonorchiasis, and opisthorchiasis, affecting millions people in some endemic areas. Amebiasis and ascariasis are believed to be the most common bowel lumen indwelling parasitic diseases, affecting billions people worldwide, but sometimes these parasites migrate inadvertently to the liver and biliary tract, resulting in liver abscess or obstructive jaundice. Imaging findings of these parasitic diseases are fairly characteristic and easy to recognize if radiologists are aware of the findings, especially in endemic areas. Because of increased immigration and frequent travelling, some patients with "exotic" parasitic diseases may be encountered in non-endemic areas, and the diagnosis may be delayed or difficult, and it is often made only after operation. This feature section was designed to provide the detailed imaging features of common parasitic diseases affecting the abdominal organs and peritoneal cavity, based on pathology-image correlation.

  4. Knockdown of genes in the Toll pathway reveals new lethal RNA interference targets for insect pest control.

    Science.gov (United States)

    Bingsohn, L; Knorr, E; Billion, A; Narva, K E; Vilcinskas, A

    2017-02-01

    RNA interference (RNAi) is a promising alternative strategy for ecologically friendly pest management. However, the identification of RNAi candidate genes is challenging owing to the absence of laboratory strains and the seasonality of most pest species. Tribolium castaneum is a well-established model, with a strong and robust RNAi response, which can be used as a high-throughput screening platform to identify potential RNAi target genes. Recently, the cactus gene was identified as a sensitive RNAi target for pest control. To explore whether the spectrum of promising RNAi targets can be expanded beyond those found by random large-scale screening, to encompass others identified using targeted knowledge-based approaches, we constructed a Cactus interaction network. We tested nine genes in this network and found that the delivery of double-stranded RNA corresponding to fusilli and cactin showed lethal effects. The silencing of cactin resulted in 100% lethality at every developmental stage from the larva to the adult. The knockdown of pelle, Dorsal-related immunity factor and short gastrulation reduced or even prevented egg hatching in the next generation. The combination of such targets with lethal and parental RNAi effects can now be tested against different pest species in field studies.

  5. Influence of sub-lethal stresses on the survival of lactic acid bacteria after spray-drying in orange juice.

    Science.gov (United States)

    Barbosa, J; Borges, S; Teixeira, P

    2015-12-01

    The demand for new functional non-dairy based products makes the production of a probiotic orange juice powder an encouraging challenge. However, during drying process and storage, loss of viability of the dried probiotic cultures can occur, since the cells are exposed to various stresses. The influence of sub-lethal conditions of temperature, acidic pH and hydrogen peroxide on the viability of Pediococcus acidilactici HA-6111-2 and Lactobacillus plantarum 299v during spray drying in orange juice and subsequent storage under different conditions was investigated. At the end of storage, the survival of both microorganisms through simulated gastro-intestinal tract (GIT) conditions was also determined. The viability of cells previously exposed to each stress was not affected by the drying process. However, during 180 days of storage at room temperature, unlike P. acidilactici HA-6111-2, survival of L. plantarum 299v was enhanced by prior exposure to sub-lethal conditions. Previous exposure to sub-lethal stresses of each microorganism did not improve their viability after passage through simulated GIT. Nevertheless, as cellular inactivation during 180 days of storage was low, both microorganisms were present in numbers of ca. 10(7) cfu/mL at the end of GIT. This is an indication that both bacteria are good candidates for use in the development of an orange juice powder with functional characteristics.

  6. Association of parasitic infections and cancers.

    Science.gov (United States)

    Khurana, S; Dubey, M L; Malla, N

    2005-04-01

    Recent advances in the fields of molecular biology, epidemiology and infectious diseases have led to significant revelations to clarify the relationship between cancer and infective agents. This article reviews the relationship between parasitic infections and carcinogenesis and the possible mechanisms involved. Few parasites, e.g., Schistosoma haematobium and Opisthorchis viverrini have been found to be strongly associated with bladder cancer and cholangiocarcinoma respectively. The evidence for the association of several other parasites and cancers has also been postulated.

  7. LOG PERIODIC DIPOLE ARRAY WITH PARASITIC ELEMENTS

    Science.gov (United States)

    The design and measured characteristics of dipole and monopole versions of a log periodic array with parasitic elements are discussed. In a dipole...array with parasitic elements, these elements are used in place of every alternate dipole, thereby eliminating the need of a twisted feed arrangement...for the elements to obtain log periodic performance of the anntenna. This design with parasitic elements lends itself to a monopole version of the

  8. [Anisakiasis - a little-known parasitic zoonosis].

    Science.gov (United States)

    Bardoň, Jan; Harna, Jiří; Pijáček, Martin

    2013-06-01

    Parasites of the family Anisakidae cause enteric parasitic zoonoses developing after consumption of inadequately cooked marine fish. Cases of such diseases are reported mainly from Japan or other countries where raw or uncooked fish are traditionally consumed. The presented short communication briefly reports detection of larvae of Pseudoterranova spp., parasites of the family Anisakidae, in a fresh chilled angler-fish (Lophius piscatorius) bought at a retail store in the Czech Republic.

  9. Sorosphaera viticola, a plasmodiophorid parasite of grapevine

    OpenAIRE

    Neuhauser, Sigrid; Huber, Lars; Kirchmair, Martin

    2009-01-01

    Sorosphaera viticola is a soil-borne, endophytic parasite of grapevine. It is classified within the plasmodiophorids, an enigmatic group of obligate biotrophic parasites of higher plants. Sorosphaera viticola has been found abundantly in the roots of Vitis spp. in Germany and Canada. This may indicate a global distribution of this root parasite. But its biphasic life-cycle, its soil-borne nature and its co-occurrence with other soil-borne pathogens make an assessment of the disease pattern or...

  10. Lack of dominant lethality in mice following 1-bromopropane treatment.

    Science.gov (United States)

    Yu, Wook-Joon; Kim, Jong-Choon; Chung, Moon-Koo

    2008-03-29

    1-Bromopropane (1-BP) is widely used in spray adhesives, precision cleaner, and degreaser. This study was conducted to investigate the potential of 1-BP to induce dominant lethality in mice. 1-BP was orally administered to males at doses of 300 and 600 mg/kg for 10 days before mating. Cyclophosphamide was used as a positive control (PC), which was administered intraperitoneally to males at 40 mg/kg for 5 days. The vehicle control (VC) group received corn oil only. Thereafter, males were mated with untreated females during six sequential mating periods of a week each. Males were sacrificed at the end of mating and so were the pregnant females on days 15-17 of gestation. Clinical signs, gross findings, mating index, gestation index, the numbers of corpora lutea, implantations, live fetuses, resorptions and dead fetuses, pre- and post-implantation losses, and dominant lethal mutation rate were examined. There were no treatment-related changes in clinical signs, gross findings, mating index, gestation index, number of corpora lutea and implantations, pre-implantation loss, live fetuses, resorptions, dead fetuses, post-implantation loss at any 1-BP doses tested. In the PC group, there were no treatment-related changes in mating index, gestation index, number of corpora lutea, and dead fetuses. However, a decrease in the number of implantations and an increase in pre-implantation loss were observed during the first 2 weeks as compared to those of the VC group. No treatment-related changes were observed in the third to sixth weeks. Increases in resorptions, fetal deaths and post-implantation loss, and a decrease in the number of live fetuses were observed in the first 3 weeks of the PC group compared to those of the VC group. However, no treatment-related changes were observed during the forth to sixth weeks. An increase in dominant lethal mutation rate was observed in 1-3 weeks of mating of the PC group, but there was no significant difference in 1-6 weeks of mating of

  11. A novel phytomyxean parasite associated with galls on the bull-kelp Durvillaea antarctica (Chamisso Hariot.

    Directory of Open Access Journals (Sweden)

    Franz Goecke

    Full Text Available Durvillaea antarctica (Fucales, Phaeophyceae is a large kelp of high ecological and economic significance in the Southern Hemisphere. In natural beds along the central coast of Chile (Pacific Ocean, abnormal growth characterized by evident gall development and discolorations of the fronds/thallus was observed. Analysing these galls by light microscopy and scanning electron microscopy revealed the presence of endophytic eukaryotes showing typical characteristics for phytomyxean parasites. The parasite developed within enlarged cells of the subcortical tissue of the host. Multinucleate plasmodia developed into many, single resting spores. The affiliation of this parasite to the Phytomyxea (Rhizaria was supported by 18S rDNA data, placing it within the Phagomyxida. Similar microorganisms were already reported once 23 years ago, indicating that these parasites are persistent and widespread in D. antarctica beds for long times. The symptoms caused by this parasite are discussed along with the ecological and economic consequences. Phytomyxean parasites may play an important role in the marine ecosystem, but they remain understudied in this environment. Our results demonstrate for the first time the presence of resting spores in Phagomyxida, an order in which resting spores were thought to be absent making this the first record of a phagomyxean parasite with a complete life cycle so far, challenging the existing taxonomic concepts within the Phytomyxea. The importance of the here described resting spores for the survival and ecology of the phagomyxid parasite will be discussed together with the impact this parasite may have on 'the strongest seaweed of the world', which is an important habitat forming and economic resource from the Southern Hemisphere.

  12. Fish Parasites: A Growing Concern During Pregnancy.

    Science.gov (United States)

    Villazanakretzer, Diana L; Napolitano, Peter G; Cummings, Kelly F; Magann, Everett F

    2016-04-01

    Intestinal parasitic worms affect more than 2 billion people worldwide according to the World Health Organization. Fish-borne parasitic infections are becoming more common with the increasing popularity of sushi, sashimi, Carpaccio, tartare, gefilte, and ceviche. The ingestion of these parasites can cause serve anemia, malabsorption, severe abdominal pain, nausea, vomiting, strong allergic reactions, and gastric ulcers. Knowledge about fish parasites and pregnancy is limited. A literature search on PubMed and Web of Science used the search terms "fish parasites" OR "diphyllobothrium" OR "anisakiasis" OR "pseudoterranova" OR ("food borne parasites" AND "fish") AND "pregnancy" OR "maternal" OR "fetus" OR "fetal" OR "newborn" OR "neonatal" OR "childbirth." No limit was put on the number of years searched. There were 281 publications identified. The abstracts of all of these publications were read. After exclusion of the articles that were not relevant to pregnancy, pregnancy outcome, and fish parasites, there were 24 articles that became the basis of this review. The pathophysiology, altered maternal immunity related to the infection, limited information about fish-borne parasitic infections and pregnancy, and treatments are discussed. The main impact of a fish-borne parasitic infection on pregnant women is anemia and altered immunity, which may increase the risk of a maternal infection. The primary fetal effects include intrauterine growth restriction and preterm delivery.

  13. Recurrence of parasite in epigastric heteropagus

    Directory of Open Access Journals (Sweden)

    Takeshi Shirai

    2017-10-01

    Full Text Available Epigastric heteropagus (EH refers to asymmetrically conjoined twins in whom an incomplete parasite is attached to the autosite's epigastric region from the xiphisternum to the umbilicus. We herein report an extremely rare case of EH in which unexpected rapid recurrence occurred 22 months after excision of the parasite. The recurrent mass comprised the intestinal wall with peristalsis-like movement, urogenital tissues, and hepatic tissue of the parasite. The recurrence was caused by a remnant of the parasite that extended from the autosite's xiphisternum to intra-abdominal cavity.

  14. Vacuolar proton pumps in malaria parasite cells.

    Science.gov (United States)

    Moriyama, Yoshinori; Hayashi, Mitsuko; Yatsushiro, Shouki; Yamamoto, Akitsugu

    2003-08-01

    The malaria parasite is a unicellular protozoan parasite of the genus Plasmodium that causes one of the most serious infectious diseases for human beings. Like other protozoa, the malaria parasite possesses acidic organelles, which may play an essential role(s) in energy acquisition, resistance to antimalarial agents, and vesicular trafficking. Recent evidence has indicated that two types of vacuolar proton pumps, vacuolar H+-ATPase and vacuolar H+-pyrophosphatase, are responsible for their acidification. In this mini-review, we discuss the recent progress on vacuolar proton pumps in the malaria parasite.

  15. 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.

  16. 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.

  17. Energy parasites trigger oncogene mutation.

    Science.gov (United States)

    Pokorný, Jiří; Pokorný, Jan; Jandová, Anna; Kobilková, Jitka; Vrba, Jan; Vrba, Jan

    2016-10-01

    Cancer initialization can be explained as a result of parasitic virus energy consumption leading to randomized genome chemical bonding. Analysis of experimental data on cell-mediated immunity (CMI) containing about 12,000 cases of healthy humans, cancer patients and patients with precancerous cervical lesions disclosed that the specific cancer and the non-specific lactate dehydrogenase-elevating (LDH) virus antigen elicit similar responses. The specific antigen is effective only in cancer type of its origin but the non-specific antigen in all examined cancers. CMI results of CIN patients display both healthy and cancer state. The ribonucleic acid (RNA) of the LDH virus parasitizing on energy reduces the ratio of coherent/random oscillations. Decreased effect of coherent cellular electromagnetic field on bonding electrons in biological macromolecules leads to elevating probability of random genome reactions. Overlapping of wave functions in biological macromolecules depends on energy of the cellular electromagnetic field which supplies energy to bonding electrons for selective chemical bonds. CMI responses of cancer and LDH virus antigens in all examined healthy, precancerous and cancer cases point to energy mechanism in cancer initiation. Dependence of the rate of biochemical reactions on biological electromagnetic field explains yet unknown mechanism of genome mutation.

  18. Apoptotic markers in protozoan parasites

    Directory of Open Access Journals (Sweden)

    Fasel Nicolas

    2010-11-01

    Full Text Available Abstract The execution of the apoptotic death program in metazoans is characterized by a sequence of morphological and biochemical changes that include cell shrinkage, presentation of phosphatidylserine at the cell surface, mitochondrial alterations, chromatin condensation, nuclear fragmentation, membrane blebbing and the formation of apoptotic bodies. Methodologies for measuring apoptosis are based on these markers. Except for membrane blebbing and formation of apoptotic bodies, all other events have been observed in most protozoan parasites undergoing cell death. However, while techniques exist to detect these markers, they are often optimised for metazoan cells and therefore may not pick up subtle differences between the events occurring in unicellular organisms and multi-cellular organisms. In this review we discuss the markers most frequently used to analyze cell death in protozoan parasites, paying special attention to changes in cell morphology, mitochondrial activity, chromatin structure and plasma membrane structure/permeability. Regarding classical regulators/executors of apoptosis, we have reviewed the present knowledge of caspase-like and nuclease activities.

  19. Apoptotic markers in protozoan parasites.

    Science.gov (United States)

    Jiménez-Ruiz, Antonio; Alzate, Juan Fernando; Macleod, Ewan Thomas; Lüder, Carsten Günter Kurt; Fasel, Nicolas; Hurd, Hilary

    2010-11-09

    The execution of the apoptotic death program in metazoans is characterized by a sequence of morphological and biochemical changes that include cell shrinkage, presentation of phosphatidylserine at the cell surface, mitochondrial alterations, chromatin condensation, nuclear fragmentation, membrane blebbing and the formation of apoptotic bodies. Methodologies for measuring apoptosis are based on these markers. Except for membrane blebbing and formation of apoptotic bodies, all other events have been observed in most protozoan parasites undergoing cell death. However, while techniques exist to detect these markers, they are often optimised for metazoan cells and therefore may not pick up subtle differences between the events occurring in unicellular organisms and multi-cellular organisms.In this review we discuss the markers most frequently used to analyze cell death in protozoan parasites, paying special attention to changes in cell morphology, mitochondrial activity, chromatin structure and plasma membrane structure/permeability. Regarding classical regulators/executors of apoptosis, we have reviewed the present knowledge of caspase-like and nuclease activities.

  20. [Bladder tumor lethality. Results in the autonomous community of Rioja between 1975-1991].

    Science.gov (United States)

    Fernández Fernández, A; Gil Fabra, J; Fernández Ruíz, M; Angulo Castellanos, M G; Blanco Martín, E; Otero Mauricio, G

    1998-01-01

    Between 1975-1991, a total of 557 cases of bladder carcinoma were identified in the Autonomous Community of La Rioja (CAR) which were followed up to December 1994. The overall lethality was 21.9%. 492 cases with 22.35% lethality were identified in males. In females, however, there was 65 cases with 18.46% lethality. The comparison of males and females lethality resulted in p = 0.525. Lethality between cases diagnosed within each 5-year period analyzed is: 1975-1981: 177 cases, lethality 23.72%. 1982-1986: 168 cases, lethality 30.95%. 1987-1991: 212 cases, lethality 13.20%. Between the first and the second 5-year periods, p = 0.132; between the first and third 5-year periods p = 0.007 and between the second and third 5-year periods p CAR for a 22.35% lethality. Lethality is higher in males that in females but the difference is not statistically significant. In the last 5-year period assessed, 1987-1991, a reduction of lethality from bladder neoplasms has been documented.

  1. [Discussion on the usage of terminology of some parasites and parasitic diseases].

    Science.gov (United States)

    Wang, Zhong-quan; Cui, Jing

    2006-04-30

    According to the International Code of Zoological Nomenclature and the Standardized Nomenclature of Animal Parasitic Diseases (SNOAPAD), and considering the new advances in parasitology, the usage of the terminology of some parasites and parasitic diseases (such as Trichinella and trichinellosis, filariae and filariasis, Echinococcus and echinococcosis, etc.) was discussed.

  2. 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.

  3. Biological invasions and host-parasite coevolution: different coevolutionary trajectories along separate parasite invasion fronts

    NARCIS (Netherlands)

    Feis, M.E.; Goedknegt, M.A.; Thieltges, D.W.; Buschbaum, C.; Wegner, K.M.

    2016-01-01

    Host–parasite coevolution has rarely been observed in natural systems. Its study often relies on microparasitic infections introducing a potential bias in the estimation of the evolutionary change of host and parasite traits. Using biological invasions as a tool to study host–parasite coevolution in

  4. One world health: socioeconomic burden and parasitic disease control priorities.

    Science.gov (United States)

    Torgerson, Paul R

    2013-08-01

    Parasitic diseases present a considerable socio-economic impact to society. Zoonotic parasites can result in a considerable burden of disease in people and substantive economic losses to livestock populations. Ameliorating the effects of these diseases may consist of attempts at eradicating specific diseases at a global level, eliminating them at a national or local level or controlling them to minimise incidence. Alternatively with some parasitic zoonoses it may only be possible to treat human and animal cases as they arise. The choice of approach will be determined by the potential effectiveness of a disease control programme, its cost and the cost effectiveness or cost benefit of undertaking the intervention. Furthermore human disease burden is being increasingly measured by egalitarian non-financial measures which are difficult to apply to livestock. This adds additional challenges to the assessment of socio-economic burdens of zoonotic diseases. Using examples from the group of neglected zoonotic diseases, information regarding the socio-economic effects is reviewed together with how this information is used in decision making with regard to disease control and treatment.

  5. Antagonistic experimental coevolution with a parasite increases host recombination frequency

    Directory of Open Access Journals (Sweden)

    Kerstes Niels AG

    2012-02-01

    Full Text Available Abstract Background One of the big remaining challenges in evolutionary biology is to understand the evolution and maintenance of meiotic recombination. As recombination breaks down successful genotypes, it should be selected for only under very limited conditions. Yet, recombination is very common and phylogenetically widespread. The Red Queen Hypothesis is one of the most prominent hypotheses for the adaptive value of recombination and sexual reproduction. The Red Queen Hypothesis predicts an advantage of recombination for hosts that are coevolving with their parasites. We tested predictions of the hypothesis with experimental coevolution using the red flour beetle, Tribolium castaneum, and its microsporidian parasite, Nosema whitei. Results By measuring recombination directly in the individuals under selection, we found that recombination in the host population was increased after 11 generations of coevolution. Detailed insights into genotypic and phenotypic changes occurring during the coevolution experiment furthermore helped us to reconstruct the coevolutionary dynamics that were associated with this increase in recombination frequency. As coevolved lines maintained higher genetic diversity than control lines, and because there was no evidence for heterozygote advantage or for a plastic response of recombination to infection, the observed increase in recombination most likely represented an adaptive host response under Red Queen dynamics. Conclusions This study provides direct, experimental evidence for an increase in recombination frequency under host-parasite coevolution in an obligatory outcrossing species. Combined with earlier results, the Red Queen process is the most likely explanation for this observation.

  6. Parasites of freshwater fishes in North America: why so neglected?

    Science.gov (United States)

    Scholz, Tomáš; Choudhury, Anindo

    2014-02-01

    Fish parasitology has a long tradition in North America and numerous parasitologists have contributed considerably to the current knowledge of the diversity and biology of protistan and metazoan parasites of freshwater fishes. The Journal of Parasitology has been essential in disseminating this knowledge and remains a significant contributor to our understanding of fish parasites in North America as well as more broadly at the international level. However, with a few exceptions, the importance of fish parasites has decreased during the last decades, which is reflected in the considerable decline of funding and corresponding decrease of attention paid to these parasites in Canada and the United States of America. After the 'golden age' in the second half of the 20th Century, fish parasitology in Canada and the United States went in a new direction, driven by technology and a shift in priorities. In contrast, fish parasitology in Mexico has undergone rapid development since the early 1990s, partly due to extensive international collaboration and governmental funding. A critical review of the current data on the parasites of freshwater fishes in North America has revealed considerable gaps in the knowledge of their species composition, host specificity, life cycles, evolution, phylogeography, and relationships with their fish hosts. As to the key question, "Why so neglected?" this is probably because: (1) fish parasites are not in the forefront due to their lesser economic importance; (2) there is little funding for this kind of research, especially if a practical application is not immediately apparent; and (3) of shifting interests and a shortage of key personalities to train a new generation (they switched to marine habitats or other fields). Some of the opportunities for future research are outlined, such as climate change and cryptic species diversity. A significant problem challenging future research seems to be the loss of trained and experienced fish

  7. Plant defenses against parasitic plants show similarities to those induced by herbivores and pathogens

    Science.gov (United States)

    Justin B. Runyon; Mark C. Mescher; Consuelo M. De Moraes

    2010-01-01

    Herbivores and pathogens come quickly to mind when one thinks of the biotic challenges faced by plants. Important but less appreciated enemies are parasitic plants, which can have important consequences for the fitness and survival of their hosts. Our knowledge of plant perception, signaling and response to herbivores and pathogens has expanded rapidly in recent years...

  8. Batflies Parasitic on Some Phyllostomid Bats in Southeastern Brazil: Parasitism Rates and Host-parasite Relationships

    Directory of Open Access Journals (Sweden)

    Carlos A Komeno

    1999-03-01

    Full Text Available Ectoparasitic batflies were studied on 12 species of phyllostomid bats, by making 35 nightly collections of bats using mist nets at the "Panga" Ecological Reservation near Uberlândia, State of Minas Gerais, southeastern Brazil, from August 1989 to July 1990. Eleven species of Streblidae and one of Nycteribiidae were collected on 12 species of bats. Prevalence of ectoparasitic flies was lower than those reported by other authors for the New World and may be the result of the lack of caves in the study area, causing bats to roost in less favorable locations, forming smaller colonies. The fly, Trichobius joblingi Wenzel, was found on Carollia perspicillata (Linnaeus, showing preference for adult male bats. This could be explained by the predominance of males in the bat colonies, and by the fact that females rest in isolation during the reproductive period making them less exposed to the parasites. The streblid flies, Aspidoptera falcata Wenzel and Megistopoda proxima (Séguy, were found on Sturnira lilium (Geoffroy. A. falcata occurred mainly on young and adult females, whereas M. proxima did not show any preferences relative to the reproductive condition of the host. Ecological factors are important in determining differential numbers of parasites occurring on the different sexes, ages and reproductive state of the hosts.

  9. Complications and lethality rate in the surgery of cerebral aneurysms

    Directory of Open Access Journals (Sweden)

    Roganović Zoran

    2002-01-01

    Full Text Available Aim. To establish the risk factors for complications and fatal outcome after the operative occlusion of cerebral aneurysms. Methods. Retrospective study on 91 (lethality rate and on 72 operated patients (complications. For survived and dead patients, as well as for patients with and without complications, following parameters were compared: gender, age, clinical condition, preoperative interval, use of temporary clips, vasospasm, outcome, as well as localization, size and intraoperative rupture of the aneurysm. Results. Complications existed: in 54.5% of aneurysms of middle cerebral and 13.6% of aneurysms of internal carotid artery (p<0.01; in 18.2% of patients in the first and 45.8% of patients in the third clinical Hunt and Hess group (p<0.05; in 57.9% of patients with and 20.5% of patients without intraoperative rupture (p<0.01; in 50% of patients with and 18.7% of patients without vasospasm (p<0.05. Average aneurysmal size was 18 mm in group with complications and 10.8 mm in patients with no complications (p<0.05, while average preoperative intervals in these two groups were 20 and 8.7 days (p<0.05. Lethality rate was 25% for the third and 83.3% for the fourth and fifth clinical group (p<0.01, and the existence of complications significantly increased mortality (from 15.7% to 50%, p<0.01. Good outcome existed in 19.2% of operated patients with complications and in 78.3% of those without complications (p<0.01. Conclusions. Incidence of complications depended significantly on preoperative clinical condition, duration of preoperative interval, size, localization and intraoperative rupture of aneurysm. Complications significantly minimized the surgical treatment outcome and increased the lethality rate mortality.

  10. 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

    2016-01-01

    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. PMID:27958200

  11. Investigating the burden of parasitic zoonotic diseases

    OpenAIRE

    2010-01-01

    Although the global burden for most parasitic zoonoses is not yet known, it is clear that collectively parasitic zoonoses have a similar human disease burden to any one of the big three human infectious diseases: malaria, tuberculosis or HIV. In addition many also have a substantial animal health and economic burden.

  12. 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.

  13. Cell fractionation of parasitic protozoa: a review

    Directory of Open Access Journals (Sweden)

    Souza Wanderley de

    2003-01-01

    Full Text Available Cell fractionation, a methodological strategy for obtaining purified organelle preparations, has been applied successfully to parasitic protozoa by a number of investigators. Here we present and discuss the work of several groups that have obtained highly purified subcellular fractions from trypanosomatids, Apicomplexa and trichomonads, and whose work have added substantially to our knowledge of the cell biology of these parasites.

  14. Mistletoe ecophysiology: Host-parasite interactions

    Science.gov (United States)

    G. Glatzel; B. W. Geils

    2009-01-01

    Mistletoes are highly specialized perennial flowering plants adapted to parasitic life on aerial parts of their hosts. In our discussion on the physiological interactions between parasite and host, we focus on water relations, mineral nutrition, and the effect of host vigour. When host photosynthesis is greatest, the xylem water potential of the host is most negative....

  15. Rodent malaria parasites : genome organization & comparative genomics

    NARCIS (Netherlands)

    Kooij, Taco W.A.

    2006-01-01

    The aim of the studies described in this thesis was to investigate the genome organization of rodent malaria parasites (RMPs) and compare the organization and gene content of the genomes of RMPs and the human malaria parasite P. falciparum. The release of the complete genome sequence of P. falciparu

  16. Rodent malaria parasites : genome organization & comparative genomics

    NARCIS (Netherlands)

    Kooij, Taco W.A.

    2006-01-01

    The aim of the studies described in this thesis was to investigate the genome organization of rodent malaria parasites (RMPs) and compare the organization and gene content of the genomes of RMPs and the human malaria parasite P. falciparum. The release of the complete genome sequence of P.

  17. Besnoitiosis in rodents from Colorado. [Parasitic infestations

    Energy Technology Data Exchange (ETDEWEB)

    Dagle, G E; Winsor, T F; Adee, R R

    1976-01-01

    Parasitic cysts of Besnoitia jellisoni (coccidia) were found in rodents (Peromyscus maniculatus and Spermophilus tridecemlineatus) trapped in Eastern Colorado. The parasite was associated with a granulomatous inflammatory reaction in the lungs of each rodent and was disseminated in several organs from one Peromyscus. The ultrastructural appearance of the merozoites and the cyst wall formed by the host cell were studied.

  18. Parasites in the Wadden Sea food web

    NARCIS (Netherlands)

    Thieltges, D.W.; Engelsma, M.Y.; Wendling, C.C.; Wegner, M.

    2013-01-01

    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

  19. Mixed infections and hybridisation in monogenean parasites.

    Directory of Open Access Journals (Sweden)

    Bettina Schelkle

    Full Text Available Theory predicts that sexual reproduction promotes disease invasion by increasing the evolutionary potential of the parasite, whereas asexual reproduction tends to enhance establishment success and population growth rate. Gyrodactylid monogeneans are ubiquitous ectoparasites of teleost fish, and the evolutionary success of the specious Gyrodactylus genus is thought to be partly due to their use of various modes of reproduction. Gyrodactylus turnbulli is a natural parasite of the guppy (Poecilia reticulata, a small, tropical fish used as a model for behavioural, ecological and evolutionary studies. Using experimental infections and a recently developed microsatellite marker, we conclusively show that monogenean parasites reproduce sexually. Conservatively, we estimate that sexual recombination occurs and that between 3.7-10.9% of the parasites in our experimental crosses are hybrid genotypes with ancestors from different laboratory strains of G. turnbulli. We also provide evidence of hybrid vigour and/or inter-strain competition, which appeared to lead to a higher maximum parasite load in mixed infections. Finally, we demonstrate inbreeding avoidance for the first time in platyhelminths which may influence the distribution of parasites within a host and their subsequent exposure to the host's localized immune response. Combined reproductive modes and inbreeding avoidance may explain the extreme evolutionary diversification success of parasites such as Gyrodactylus, where host-parasite coevolution is punctuated by relatively frequent host switching.

  20. Parasites in the Wadden Sea food web

    NARCIS (Netherlands)

    Thieltges, D.W.; Engelsma, M.Y.; Wendling, C.C.; Wegner, K.M.

    2013-01-01

    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

  1. 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.

  2. Lethal subarachnoid bleeding under immunosuppressive therapy due to mycotic arteritis

    Energy Technology Data Exchange (ETDEWEB)

    Weigel, S.; Kloska, S.; Freund, M. [Dept. of Clinical Radiology, Univ. Hospital of Muenster, Muenster (Germany); Kehl, H.G. [Dept. of Pediatric Cardiology, Univ. Hospital of Muenster, Muenster (Germany)

    2003-12-01

    A subarachnoid haemorrhage (SAH) occurred 67 days after cardiac transplantation in 10-year-old girl with consecutive immunocompromising therapy. Neither digital subtraction angiography (DSA) nor computed tomographic angiography showed signs of intracranial vascular malformations. One month before the lethal SAH occurred, she had developed arterial hypertension and attacks of severe headache with cerebrospinal fluid (CSF) pleocytosis while CT scans showed an infarct of the left thalamus. Pathologic findings established the rare diagnosis of SAH due to aspergillosis-related mycotic arteritis. Imaging characteristics are presented. (orig.)

  3. Perinatal lethal type II osteogenesis imperfecta: a case report.

    Science.gov (United States)

    Ayadi, Imene Dahmane; Hamida, Emira Ben; Rebeh, Rania Ben; Chaouachi, Sihem; Marrakchi, Zahra

    2015-01-01

    We report a new case of osteogenesis imperfecta (OI) type II which is a perinatal lethal form. First trimester ultrasound didn't identified abnormalities. Second trimester ultrasound showed incurved limbs, narrow chest, with hypomineralization and multiple fractures of ribs and long bones. Parents refused pregnancy termination; they felt that the diagnosis was late. At birth, the newborn presented immediate respiratory distress. Postnatal examination and bone radiography confirmed the diagnosis of OI type IIA. Death occurred on day 25 of life related to respiratory failure.

  4. Clinics in diagnostic imaging (112). Perinatal lethal hypophosphatasia (PLH).

    Science.gov (United States)

    Kritsaneepaiboon, S; Jaruratanasirikul, S; Dissaneevate, S

    2006-11-01

    A two-hour-old female infant presented with respiratory distress and short limbs. Neonatal radiographs showed micromelic dwarfism and generalised demineralisation, especially at the ribs, long bones of both forearms and both fibulae. The spine showed a flattened shape. All long bones showed metaphyseal irregularities and flaring. Normal serum calcium and elevated serum phosphorus were found, while serum alkaline phosphatase was markedly reduced. A diagnosis of perinatal lethal hypophosphatasia was made. The aetiology, clinical manifestations, radiographical findings, laboratory assays, prenatal diagnosis and treatment of hypophosphatasia are discussed.

  5. Using parasitic trematode larvae to quantify an elusive vertebrate host.

    Science.gov (United States)

    Byers, James E; Altman, Irit; Grosse, Andrew M; Huspeni, Todd C; Maerz, John C

    2011-02-01

    Digenean trematode parasites require multiple host species to complete their life cycles, and their abundance can often be strongly correlated with the abundance of their host species. Species richness and abundance of parasites in easily sampled host species may yield an accurate estimate of the species richness and abundance of other hosts in a parasite's life cycle that are difficult to survey directly. Accordingly, we investigated whether prevalence and mean abundance of trematodes could be used to estimate the abundance of one of their host species, diamondback terrapins (Malaclemys terrapin), which are difficult to sample and are designated as near threatened (by the International Union for Conservation of Nature [IUCN Red List]) along some U.S. coasts. As an adult the trematode Pleurogonius malaclemys is specific to terrapins. Its larval stages live first inside mud snails (Ilyanassa obsoleta) and are subsequently shed into the environment where they form external metacercarial cysts on hard surfaces such as snail opercula. The life cycle of P. malaclemys is completed when terrapins ingest these cysts. At 12 sites along the coast of Georgia (U.S.A.), we determined the prevalence of internal P. malaclemys larvae in mud snails (proportion of infected snails in a population) and the prevalence and mean abundance of external trematode cysts. We examined whether these data were correlated with terrapin abundance, which we estimated with mark-recapture methods. The abundance of external cysts and salinity explained ≥59% of the variability in terrapin abundance. We suggest that dependent linkages between the life stages of multihost parasites make them reliable predictors of host species' abundance, including hosts with abundances that are challenging to quantify directly.

  6. Parasites can enhance infections of fish with bacterial pathogens

    Science.gov (United States)

    In aquaculture systems, fish are commonly infected by multiple pathogens, including parasites. Parasite Ichthyophthirius multifiliis (Ich) and bacterium Edwardsiella ictaluri are two common pathogens of cultured channel catfish. The objectives were to 1) evaluate the susceptibility of Ich parasitize...

  7. Trichinella spiralis: the evolution of adaptation and parasitism

    Science.gov (United States)

    Parasitism among nematodes has occurred in multiple, independent events. Deciphering processes that drive species diversity and adaptation are keys to understanding parasitism and advancing control strategies. Studies have been put forth on morphological and physiological aspects of parasitism and a...

  8. A description of parasites from Iranian snakes.

    Science.gov (United States)

    Nasiri, Vahid; Mobedi, Iraj; Dalimi, Abdolhossein; Mirakabadi, Abbas Zare; Ghaffarifar, Fatemeh; Teymurzadeh, Shohreh; Karimi, Gholamreza; Abdoli, Amir; Paykari, Habibollah

    2014-12-01

    Little is known of the parasitic fauna of terrestrial snakes in Iran. This study aimed to evaluate the parasitic infection rates of snakes in Iran. A total of 87 snakes belonging to eight different species, that were collected between May 2012 and September 2012 and died after the hold in captivity, under which they were kept for taking poisons, were examined for the presence of gastrointestinal and blood parasites. According to our study 12 different genera of endoparasites in 64 (73.56%) of 87 examined snakes were determined. Forty one snakes (47.12%) had gastrointestinal parasites. In prepared blood smears, it was found that in 23 (26.43%) of 87 examined snakes there are at least one hemoparasite. To our knowledge, these are the first data on the internal parasitic fauna of Iranian terrestrial snakes and our findings show a higher prevalence of these organisms among them.

  9. Parasitism in bivalves from an Arctic ecosystem

    Science.gov (United States)

    Petersen, G. Høpner

    1984-03-01

    In arctic ecosystems parasitism seems less conspicuous than in more diverse tropical ecosystems. However, several host-parasite relations may be a burden in Arctic ecosystems and modify energy-flow patterns. Four different localities of the shallow shelf off Godhavn, West Greenland, were studied with regard to biomass, production and life cycles of selected bivalve and polychaete species. The following important parasite-bivalve associations were found: the athecate hydroid Monobrachium parasitum on Macoma calcarea; the digenetic trematode Gymnophallus somateriae in Hiatella byssifera; an unidentified species of turbellarian in Hiatella byssifera; and the nemertean Malacobdella grossa in Mya truncata. In the bivalves Mytilus edulis, Serripes groenlandicus and Cardium ciliatum only few parasites were detected. Parasitism seems to follow the general trend observed in Arctic ecosystems which exhibit low species diversities and high numbers of individuals.

  10. Palaeoparasitology - Human Parasites in Ancient Material.

    Science.gov (United States)

    Araújo, Adauto; Reinhard, Karl; Ferreira, Luiz Fernando

    2015-01-01

    Parasite finds in ancient material launched a new field of science: palaeoparasitology. Ever since the pioneering studies, parasites were identified in archaeological and palaeontological remains, some preserved for millions of years by fossilization. However, the palaeoparasitological record consists mainly of parasites found specifically in human archaeological material, preserved in ancient occupation sites, from prehistory until closer to 2015. The results include some helminth intestinal parasites still commonly found in 2015, such as Ascaris lumbricoides, Trichuris trichiura and hookworms, besides others such as Amoebidae and Giardia intestinalis, as well as viruses, bacteria, fungi and arthropods. These parasites as a whole provide important data on health, diet, climate and living conditions among ancient populations. This chapter describes the principal findings and their importance for knowledge on the origin and dispersal of infectious diseases.

  11. Plant defenses against parasitic plants show similarities to those induced by herbivores and pathogens.

    Science.gov (United States)

    Runyon, Justin B; Mescher, Mark C; De Moraes, Consuelo M

    2010-08-01

    Herbivores and pathogens come quickly to mind when one thinks of the biotic challenges faced by plants. Important but less appreciated enemies are parasitic plants, which can have important consequences for the fitness and survival of their hosts. Our knowledge of plant perception, signaling, and response to herbivores and pathogens has expanded rapidly in recent years, but information is generally lacking for parasitic species. In a recent paper we reported that some of the same defense responses induced by herbivores and pathogens--notably increases in jasmonic acid (JA), salicylic acid (SA), and a hypersensitive-like response (HLR)--also occur in tomato plants upon attack by the parasitic plant Cuscuta pentagona (field dodder). Parasitism induced a distinct pattern of JA and SA accumulation, and growth trials using genetically-altered tomato hosts suggested that both JA and SA govern effective defenses against the parasite, though the extent of the response varied with host plant age. Here we discuss similarities between the induced responses we observed in response to Cuscuta parasitism to those previously described for herbivores and pathogens and present new data showing that trichomes should be added to the list of plant defenses that act against multiple enemies and across Kingdoms.

  12. PARASITE MYCOPOPULATION OF SOYBEAN GRAIN

    Directory of Open Access Journals (Sweden)

    Jasenka Ćosić

    2008-07-01

    Full Text Available Disease appearance on soybean can influence quality and quantity of yield. Different spieces of saprophyte and parasite fungi can be isolated from stems, pods and grain of soybean. The aim of the research was to evaluate the incidence of important disease on natural soybean grain over the period of 4 years (2004-2007 of experiment held on the location Sopot-Vinkovci and included 9 cultivars of soybean. The following plant pathogenic fungi were identified: Peronospora, Sclerotinia, Cercospora, Fusarium and Diaporthe/Phomopsis. The most frequent fungi on soybean grains were: Cladosporium, Alternaria, Penicillium, Aspergillus and Epicoccum. The health condition of the natural soybean grains over the four years period on all cultivars was good.

  13. Parasitic Events in Envelope Analysis

    Directory of Open Access Journals (Sweden)

    J. Doubek

    2001-01-01

    Full Text Available Envelope analysis allows fast fault location of individual gearboxes and parts of bearings by repetition frequency determination of the mechanical catch of an amplitude-modulated signal. Systematic faults arise when using envelope analysis on a signal with strong changes. The source of these events is the range of function definition of used in convolution integral definition. This integral is used for Hilbert image calculation of analyzed signal. Overshoots (almost similar to Gibbs events on a synthetic signal using the Fourier series are result from these faults. Overshoots are caused by parasitic spectral lines in the frequency domain, which can produce faulty diagnostic analysis.This paper describes systematic arising during faults rising by signal numerical calculation using envelope analysis with Hilbert transform. It goes on to offer a mathematical analysis of these systematic faults.

  14. Mitochondrial genomes of parasitic flatworms.

    Science.gov (United States)

    Le, Thanh H; Blair, David; McManus, Donald P

    2002-05-01

    Complete or near-complete mitochondrial genomes are now available for 11 species or strains of parasitic flatworms belonging to the Trematoda and the Cestoda. The organization of these genomes is not strikingly different from those of other eumetazoans, although one gene (atp8) commonly found in other phyla is absent from flatworms. The gene order in most flatworms has similarities to those seen in higher protostomes such as annelids. However, the gene order has been drastically altered in Schistosoma mansoni, which obscures this possible relationship. Among the sequenced taxa, base composition varies considerably, creating potential difficulties for phylogeny reconstruction. Long non-coding regions are present in all taxa, but these vary in length from only a few hundred to approximately 10000 nucleotides. Among Schistosoma spp., the long non-coding regions are rich in repeats and length variation among individuals is known. Data from mitochondrial genomes are valuable for studies on species identification, phylogenies and biogeography.

  15. Parasite remains in archaeological sites.

    Science.gov (United States)

    Bouchet, Françoise; Guidon, Niéde; Dittmar, Katharina; Harter, Stephanie; Ferreira, Luiz Fernando; Chaves, Sergio Miranda; Reinhard, Karl; Araújo, Adauto

    2003-01-01

    Organic remains can be found in many different environments. They are the most significant source for paleoparasitological studies as well as for other paleoecological reconstruction. Preserved paleoparasitological remains are found from the driest to the moistest conditions. They help us to understand past and present diseases and therefore contribute to understanding the evolution of present human sociality, biology, and behavior. In this paper, the scope of the surviving evidence will be briefy surveyed, and the great variety of ways it has been preserved in different environments will be discussed. This is done to develop to the most appropriated techniques to recover remaining parasites. Different techniques applied to the study of paleoparasitological remains, preserved in different environments, are presented. The most common materials used to analyze prehistoric human groups are reviewed, and their potential for reconstructing ancient environment and disease are emphasized. This paper also urges increased cooperation among archaeologists, paleontologists, and paleoparasitologists.

  16. The Berkeley parasitic SETI program

    Science.gov (United States)

    Bowyer, S.; Zeitlin, G.; Tarter, J.; Lampton, M.; Welch, W. J.

    1983-01-01

    Parasitic programs for the Search for Extraterrestrial Intelligence (SETI), carried out concurrently with conventional radio astronomical observing programs, can be an attractive and cost-effective means of exploring the large multidimensional search space intrinsic to this effort. A microprocessor-based automated SETI acquisition system is described which searches for, and records, spectra of narrowband signals in the IF band of an observatory receiver. Data taken with this system over 35 days at the Hat Creek Radio Observatory at 1612 MHz are discussed. Out of approximately 100,000 spectra processed during this period, 4000 were identified by the system as containing narrowband signals and were recorded. Subsequent analysis indicates that over 3900 of these are due to local RF contamination. The remainder are undergoing further investigation.

  17. Cell division in apicomplexan parasites.

    Science.gov (United States)

    Francia, Maria E; Striepen, Boris

    2014-02-01

    Toxoplasma gondii and Plasmodium falciparum are important human pathogens. These parasites and many of their apicomplexan relatives undergo a complex developmental process in the cells of their hosts, which includes genome replication, cell division and the assembly of new invasive stages. Apicomplexan cell cycle progression is both globally and locally regulated. Global regulation is carried out throughout the cytoplasm by diffusible factors that include cell cycle-specific kinases, cyclins and transcription factors. Local regulation acts on individual nuclei and daughter cells that are developing inside the mother cell. We propose that the centrosome is a master regulator that physically tethers cellular components and that provides spatial and temporal control of apicomplexan cell division.

  18. Parasite remains in archaeological sites

    Directory of Open Access Journals (Sweden)

    Françoise Bouchet

    2003-01-01

    Full Text Available Organic remains can be found in many different environments. They are the most significant source for paleoparasitological studies as well as for other paleoecological reconstruction. Preserved paleoparasitological remains are found from the driest to the moistest conditions. They help us to understand past and present diseases and therefore contribute to understanding the evolution of present human sociality, biology, and behavior. In this paper, the scope of the surviving evidence will be briefly surveyed, and the great variety of ways it has been preserved in different environments will be discussed. This is done to develop to the most appropriated techniques to recover remaining parasites. Different techniques applied to the study of paleoparasitological remains, preserved in different environments, are presented. The most common materials used to analyze prehistoric human groups are reviewed, and their potential for reconstructing ancient environment and disease are emphasized. This paper also urges increased cooperation among archaeologists, paleontologists, and paleoparasitologists.

  19. Lethality and developmental delay in Drosophila melanogaster larvae after ingestion of selected Pseudomonas fluorescens strains.

    Directory of Open Access Journals (Sweden)

    Marika H Olcott

    Full Text Available BACKGROUND: The fruit fly, Drosophila melanogaster, is a well-established model organism for probing the molecular and cellular basis of physiological and immune system responses of adults or late stage larvae to bacterial challenge. However, very little is known about the consequences of bacterial infections that occur in earlier stages of development. We have infected mid-second instar larvae with strains of Pseudomonas fluorescens to determine how infection alters the ability of larvae to survive and complete development. METHODOLOGY/PRINCIPAL FINDINGS: We mimicked natural routes of infection using a non-invasive feeding procedure to study the toxicity of the three sequenced P. fluorescens strains (Pf0-1, SBW25, and Pf-5 to Drosophila melanogaster. Larvae fed with the three strains of P. fluorescens showed distinct differences in developmental trajectory and survival. Treatment with SBW25 caused a subset of insects to die concomitant with a systemic melanization reaction at larval, pupal or adult stages. Larvae fed with Pf-5 died in a dose-dependent manner with adult survivors showing eye and wing morphological defects. In addition, larvae in the Pf-5 treatment groups showed a dose-dependent delay in the onset of metamorphosis relative to control-, Pf0-1-, and SBW25-treated larvae. A functional gacA gene is required for the toxic properties of wild-type Pf-5 bacteria. CONCLUSIONS/SIGNIFICANCE: These experiments are the first to demonstrate that ingestion of P. fluorescens bacteria by D. melanogaster larvae causes both lethal and non-lethal phenotypes, including delay in the onset of metamorphosis and morphological defects in surviving adult flies, which can be decoupled.

  20. Synthetic lethal RNAi screening identifies sensitizing targets for gemcitabine therapy in pancreatic cancer

    Directory of Open Access Journals (Sweden)

    Azorsa David O

    2009-06-01

    Full Text Available Abstract Background Pancreatic cancer retains a poor prognosis among the gastrointestinal cancers. It affects 230,000 individuals worldwide, has a very high mortality rate, and remains one of the most challenging malignancies to treat successfully. Treatment with gemcitabine, the most widely used chemotherapeutic against pancreatic cancer, is not curative and resistance may occur. Combinations of gemcitabine with other chemotherapeutic drugs or biological agents have resulted in limited improvement. Methods In order to improve gemcitabine response in pancreatic cancer cells, we utilized a synthetic lethal RNAi screen targeting 572 known kinases to identify genes that when silenced would sensitize pancreatic cancer cells to gemcitabine. Results Results from the RNAi screens identified several genes that, when silenced, potentiated the growth inhibitory effects of gemcitabine in pancreatic cancer cells. The greatest potentiation was shown by siRNA targeting checkpoint kinase 1 (CHK1. Validation of the screening results was performed in MIA PaCa-2 and BxPC3 pancreatic cancer cells by examining the dose response of gemcitabine treatment in the presence of either CHK1 or CHK2 siRNA. These results showed a three to ten-fold decrease in the EC50 for CHK1 siRNA-treated cells versus control siRNA-treated cells while treatment with CHK2 siRNA resulted in no change compared to controls. CHK1 was further targeted with specific small molecule inhibitors SB 218078 and PD 407824 in combination with gemcitabine. Results showed that treatment of MIA PaCa-2 cells with either of the CHK1 inhibitors SB 218078 or PD 407824 led to sensitization of the pancreatic cancer cells to gemcitabine. Conclusion These findings demonstrate the effectiveness of synthetic lethal RNAi screening as a tool for identifying sensitizing targets to chemotherapeutic agents. These results also indicate that CHK1 could serve as a putative therapeutic target for sensitizing pancreatic cancer

  1. Development and application of an oral challenge mouse model for studying Clostridium perfringens type D infection.

    Science.gov (United States)

    Fernandez-Miyakawa, Mariano E; Sayeed, Sameera; Fisher, Derek J; Poon, Rachael; Adams, Vicki; Rood, Julian I; McClane, Bruce A; Saputo, Julian; Uzal, Francisco A

    2007-09-01

    Clostridium perfringens type D isolates cause enterotoxemia in sheep, goats, and probably cattle. While the major disease signs and lesions of type D animal disease are usually attributed to epsilon toxin, a class B select agent, these bacteria typically produce several lethal toxins. Understanding of disease pathogenesis and development of improved vaccines are hindered by the lack of a small-animal model mimicking natural disease caused by type D isolates. Addressing this need, we developed an oral challenge mouse model of C. perfringens type D enterotoxemia. When BALB/c mice with a sealed anus were inoculated by intragastric gavage with type D isolates, 7 of 10 type D isolates were lethal, as defined by spontaneous death or severe clinical signs necessitating euthanasia. The lethalities of the seven type D isolates varied between 14 and 100%. Clinical signs in the lethally challenged mice included seizures, convulsions, hyperexcitability, and/or depression. Mild intestinal gas distention and brain edema were observed at necropsy in a few mice, while histology showed multifocal acute tubular necrosis of the kidney and edema in the lungs of most challenged mice that developed a clinical response. When the lethality of type D isolates in this model was compared with in vitro toxin production, only a limited correlation was observed. However, mice could be protected against lethality by intravenous passive immunization with an epsilon toxin antibody prior to oral challenge. This study provides an economical new model for studying the pathogenesis of C. perfringens type D infections.

  2. Development and Application of an Oral Challenge Mouse Model for Studying Clostridium perfringens Type D Infection▿

    Science.gov (United States)

    Fernandez-Miyakawa, Mariano E.; Sayeed, Sameera; Fisher, Derek J.; Poon, Rachael; Adams, Vicki; Rood, Julian I.; McClane, Bruce A.; Saputo, Julian; Uzal, Francisco A.

    2007-01-01

    Clostridium perfringens type D isolates cause enterotoxemia in sheep, goats, and probably cattle. While the major disease signs and lesions of type D animal disease are usually attributed to epsilon toxin, a class B select agent, these bacteria typically produce several lethal toxins. Understanding of disease pathogenesis and development of improved vaccines are hindered by the lack of a small-animal model mimicking natural disease caused by type D isolates. Addressing this need, we developed an oral challenge mouse model of C. perfringens type D enterotoxemia. When BALB/c mice with a sealed anus were inoculated by intragastric gavage with type D isolates, 7 of 10 type D isolates were lethal, as defined by spontaneous death or severe clinical signs necessitating euthanasia. The lethalities of the seven type D isolates varied between 14 and 100%. Clinical signs in the lethally challenged mice included seizures, convulsions, hyperexcitability, and/or depression. Mild intestinal gas distention and brain edema were observed at necropsy in a few mice, while histology showed multifocal acute tubular necrosis of the kidney and edema in the lungs of most challenged mice that developed a clinical response. When the lethality of type D isolates in this model was compared with in vitro toxin production, only a limited correlation was observed. However, mice could be protected against lethality by intravenous passive immunization with an epsilon toxin antibody prior to oral challenge. This study provides an economical new model for studying the pathogenesis of C. perfringens type D infections. PMID:17562765

  3. [The new generations of vaccines against parasites].

    Science.gov (United States)

    Wedrychowicz, H

    2000-01-01

    The protection of humans and domestic animals against parasitic infections remains a major goal, especially in light of developing of drug resistant strains in many parasite species. "Classic" vaccines are based on attenuated infective stages of protozoan and helminth parasites. Although such vaccines are effective in confering host immunity against several protozoan (coccidiosis, giardiosis, toxoplasmosis) diseases and one helminth (dictyocaulosis) they are very unstable and expensive. Recombinant techniques enable to obtain protective antigens quickly and in considerable quantities, cultivating of the bacteria and purification of the recombinant protein is less expensive than the maintenance of host animals and isolation of the protective antigens from harvested parasites. Moreover, the cloned protective antigens may be deprived of epitopes responsible for immunopathology. However, at present only one anti-parasite recombinant protein vaccine is commercially available (TickGARD). Such a situation may result from that many protective parasitic antigens cannot be expressed in bacteria or yeast in anative from. DNA vaccines present many advantages over protein ones. Firstly, the antigenic proteins synthesised within the host cell possess an appropriate molecular structure and undergo a post-translational modifications specific for a native protein. The next advantage of DNA vaccines is that DNA is easier to handle and more resistant than proteins to temperature changes. DNA vaccines are likely to induce novel mechanisms of immune response, which may be beneficial in case of parasitic invasions. Costs of DNA vaccines are comparable, and may be even lower, in comparison to recombinant protein vaccines. The main obstacle preventing the use of DNA vaccines is still lack of the complete knowledge concerning mechanisms of their action. Vaccines based on transgenic plants (=edible vaccines), expressing the protective parasitic antigens, present another promising approach

  4. The role of protein interactions in mediating essentiality and synthetic lethality.

    Science.gov (United States)

    Talavera, David; Robertson, David L; Lovell, Simon C

    2013-01-01

    Genes are characterized as essential if their knockout is associated with a lethal phenotype, and these "essential genes" play a central role in biological function. In addition, some genes are only essential when deleted in pairs, a phenomenon known as synthetic lethality. Here we consider genes displaying synthetic lethality as "essential pairs" of genes, and analyze the properties of yeast essential genes and synthetic lethal pairs together. As gene duplication initially produces an identical pair or sets of genes, it is often invoked as an explanation for synthetic lethality. However, we find that duplication explains only a minority of cases of synthetic lethality. Similarly, disruption of metabolic pathways leads to relatively few examples of synthetic lethality. By contrast, the vast majority of synthetic lethal gene pairs code for proteins with related functions that share interaction partners. We also find that essential genes and synthetic lethal pairs cluster in the protein-protein interaction network. These results suggest that synthetic lethality is strongly dependent on the formation of protein-protein interactions. Compensation by duplicates does not usually occur mainly because the genes involved are recent duplicates, but is more commonly due to functional similarity that permits preservation of essential protein complexes. This unified view, combining genes that are individually essential with those that form essential pairs, suggests that essentiality is a feature of physical interactions between proteins protein-protein interactions, rather than being inherent in gene and protein products themselves.

  5. The role of protein interactions in mediating essentiality and synthetic lethality.

    Directory of Open Access Journals (Sweden)

    David Talavera

    Full Text Available Genes are characterized as essential if their knockout is associated with a lethal phenotype, and these "essential genes" play a central role in biological function. In addition, some genes are only essential when deleted in pairs, a phenomenon known as synthetic lethality. Here we consider genes displaying synthetic lethality as "essential pairs" of genes, and analyze the properties of yeast essential genes and synthetic lethal pairs together. As gene duplication initially produces an identical pair or sets of genes, it is often invoked as an explanation for synthetic lethality. However, we find that duplication explains only a minority of cases of synthetic lethality. Similarly, disruption of metabolic pathways leads to relatively few examples of synthetic lethality. By contrast, the vast majority of synthetic lethal gene pairs code for proteins with related functions that share interaction partners. We also find that essential genes and synthetic lethal pairs cluster in the protein-protein interaction network. These results suggest that synthetic lethality is strongly dependent on the formation of protein-protein interactions. Compensation by duplicates does not usually occur mainly because the genes involved are recent duplicates, but is more commonly due to functional similarity that permits preservation of essential protein complexes. This unified view, combining genes that are individually essential with those that form essential pairs, suggests that essentiality is a feature of physical interactions between proteins protein-protein interactions, rather than being inherent in gene and protein products themselves.

  6. Core genome components and lineage specific expansions in malaria parasites Plasmodium

    Directory of Open Access Journals (Sweden)

    Gu Jianying

    2010-12-01

    Full Text Available Abstract Background The increasing resistance of Plasmodium, the malaria parasites, to multiple commonly used drugs has underscored the urgent need to develop effective antimalarial drugs and vaccines. The new direction of genomics-driven target discovery has become possible with the completion of parasite genome sequencing, which can lead us to a better understanding of how the parasites develop the genetic variability that is associated with their response to environmental challenges and other adaptive phenotypes. Results We present the results of a comprehensive analysis of the genomes of six Plasmodium species, including two species that infect humans, one that infects monkeys, and three that infect rodents. The core genome shared by all six species is composed of 3,351 genes, which make up about 22%-65% of the genome repertoire. These components play important roles in fundamental functions as well as in parasite-specific activities. We further investigated the distribution and features of genes that have been expanded in specific Plasmodium lineage(s. Abundant duplicate genes are present in the six species, with 5%-9% of the whole genomes composed lineage specific radiations. The majority of these gene families are hypothetical proteins with unknown functions; a few may have predicted roles such as antigenic variation. Conclusions The core genome components in the malaria parasites have functions ranging from fundamental biological processes to roles in the complex networks that sustain the parasite-specific lifestyles appropriate to different hosts. They represent the minimum requirement to maintain a successful life cycle that spans vertebrate hosts and mosquito vectors. Lineage specific expansions (LSEs have given rise to abundant gene families in Plasmodium. Although the functions of most families remain unknown, these LSEs could reveal components in parasite networks that, by their enhanced genetic variability, can contribute to

  7. Lethal and sub-lethal effects of elevated CO2 concentrations on marine benthic invertebrates and fish.

    Science.gov (United States)

    Lee, Changkeun; Hong, Seongjin; Kwon, Bong-Oh; Lee, Jung-Ho; Ryu, Jongseong; Park, Young-Gyu; Kang, Seong-Gil; Khim, Jong Seong

    2016-08-01

    Concern about leakage of carbon dioxide (CO2) from deep-sea storage in geological reservoirs is increasing because of its possible adverse effects on marine organisms locally or at nearby coastal areas both in sediment and water column. In the present study, we examined how elevated CO2 affects various intertidal epibenthic (benthic copepod), intertidal endobenthic (Manila clam and Venus clam), sub-tidal benthic (brittle starfish), and free-living (marine medaka) organisms in areas expected to be impacted by leakage. Acute lethal and sub-lethal effects were detected in the adult stage of all test organisms exposed to varying concentrations of CO2, due to the associated decline in pH (8.3 to 5.2) during 96-h exposure. However, intertidal organisms (such as benthic copepods and clams) showed remarkable resistance to elevated CO2, with the Venus clam being the most tolerant (LpH50 = 5.45). Sub-tidal species (such as brittle starfish [LpH50 = 6.16] and marine medaka [LpH50 = 5.91]) were more sensitive to elevated CO2 compared to intertidal species, possibly because they have fewer defensive capabilities. Of note, the exposure duration might regulate the degree of acute sub-lethal effects, as evidenced by the Venus clam, which showed a time-dependent effect to elevated CO2. Finally, copper was chosen as a model toxic element to find out the synergistic or antagonistic effects between ocean acidification and metal pollution. Combination of CO2 and Cu exposure enhances the adverse effects to organisms, generally supporting a synergistic effect scenario. Overall, the significant variation in the degree to which CO2 adversely affected organisms (viz., working range and strength) was clearly observed, supporting the general concept of species-dependent effects of elevated CO2.

  8. Comparing biomarker responses during thermal acclimation: A lethal vs non-lethal approach in a tropical reef clownfish.

    Science.gov (United States)

    Madeira, Carolina; Madeira, Diana; Diniz, Mário S; Cabral, Henrique N; Vinagre, Catarina

    2017-02-01

    Knowledge of thermal stress biology for most tropical fish species in reef ecosystems under climate change is still quite limited. Thus, the objective of this study was to measure the time-course changes of thermal stress biomarkers in the commercially exploited coral reef fish Amphiprion ocellaris, during a laboratory simulated event of increased temperature. Heat shock protein 70kDa (Hsp70) and total ubiquitin (Ub) were determined in the muscle (lethal method) and in the fin (non-lethal alternative method) under two temperature treatments (control - 26°C and elevated temperature - 30°C) throughout one month with weekly samplings. Results suggest that biomarker basal levels are tissue-specific and influence the degree of response under temperature exposure. Responses were highly inducible in the muscle but not in fin tissue, indicating that the latter is not reliable for monitoring purposes. Thermal stress was observed in the muscle after one week of exposure (both biomarkers increased significantly) and Ub levels then decreased, suggesting the animals were able to acclimate by maintaining high levels of Hsp70 and through an effective protein turnover. In addition, the results show that mortality rates did not differ between treatments. This indicates that A. ocellaris is capable of displaying a plastic response to elevated temperature by adjusting the protein quality control system to protect cell functions, without decreasing survival. Thus, this coral reef fish species presents a significant acclimation potential under ocean warming scenarios of +4°C. Monitoring of thermal stress through a non-lethal method, fin-clipping, although desirable proved to be inadequate for this species. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. A LigA three-domain region protects hamsters from lethal infection by Leptospira interrogans.

    Directory of Open Access Journals (Sweden)

    Mariana L Coutinho

    2011-12-01

    Full Text Available The leptospiral LigA protein consists of 13 bacterial immunoglobulin-like (Big domains and is the only purified recombinant subunit vaccine that has been demonstrated to protect against lethal challenge by a clinical isolate of Leptospira interrogans in the hamster model of leptospirosis. We determined the minimum number and location of LigA domains required for immunoprotection. Immunization with domains 11 and 12 was found to be required but insufficient for protection. Inclusion of a third domain, either 10 or 13, was required for 100% survival after intraperitoneal challenge with Leptospira interrogans serovar Copenhageni strain Fiocruz L1-130. As in previous studies, survivors had renal colonization; here, we quantitated the leptospiral burden by qPCR to be 1.2×10(3 to 8×10(5 copies of leptospiral DNA per microgram of kidney DNA. Although renal histopathology in survivors revealed tubulointerstitial changes indicating an inflammatory response to the infection, blood chemistry analysis indicated that renal function was normal. These studies define the Big domains of LigA that account for its vaccine efficacy and highlight the need for additional strategies to achieve sterilizing immunity to protect the mammalian host from leptospiral infection and its consequences.

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

    Science.gov (United States)

    Hopp, Ann-Katrin; Saenger, Mélanie; Soichot, Julien; Scholze, Heidi; Boch, Jens; Blandin, Stéphanie A.; Marois, Eric

    2017-01-01

    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. PMID:28095489

  11. Genetic mapping identifies novel highly protective antigens for an apicomplexan parasite.

    Directory of Open Access Journals (Sweden)

    Damer P Blake

    Full Text Available Apicomplexan parasites are responsible for a myriad of diseases in humans and livestock; yet despite intensive effort, development of effective sub-unit vaccines remains a long-term goal. Antigenic complexity and our inability to identify protective antigens from the pool that induce response are serious challenges in the development of new vaccines. Using a combination of parasite genetics and selective barriers with population-based genetic fingerprinting, we have identified that immunity against the most important apicomplexan parasite of livestock (Eimeria spp. was targeted against a few discrete regions of the genome. Herein we report the identification of six genomic regions and, within two of those loci, the identification of true protective antigens that confer immunity as sub-unit vaccines. The first of these is an Eimeria maxima homologue of apical membrane antigen-1 (AMA-1 and the second is a previously uncharacterised gene that we have termed 'immune mapped protein-1' (IMP-1. Significantly, homologues of the AMA-1 antigen are protective with a range of apicomplexan parasites including Plasmodium spp., which suggest that there may be some characteristic(s of protective antigens shared across this diverse group of parasites. Interestingly, homologues of the IMP-1 antigen, which is protective against E. maxima infection, can be identified in Toxoplasma gondii and Neospora caninum. Overall, this study documents the discovery of novel protective antigens using a population-based genetic mapping approach allied with a protection-based screen of candidate genes. The identification of AMA-1 and IMP-1 represents a substantial step towards development of an effective anti-eimerian sub-unit vaccine and raises the possibility of identification of novel antigens for other apicomplexan parasites. Moreover, validation of the parasite genetics approach to identify effective antigens supports its adoption in other parasite systems where legitimate

  12. Effectiveness of lethal, directed wolf-depredation control in Minnesota

    Science.gov (United States)

    Harper, E.K.; Paul, W.J.; Mech, L.D.; Weisberg, S.

    2008-01-01

    Wolf (Canis lupus) depredations on livestock in Minnesota, USA, are an economic problem for many livestock producers, and depredating wolves are lethally controlled. We sought to determine the effectiveness of lethal control through the analysis of data from 923 government-verified wolf depredations from 1979 to 1998. We analyzed the data by 1) assessing the correlations between the number of wolves killed in response to depredations with number of depredations the following year at state and local levels, and 2) the time to the next depredation. No analysis indicated that trapping wolves substantially reduced the following year's depredations at state or local levels. However, more specific analyses indicated that in certain situations, killing wolves was more effective than no action (i.e., not trapping). For example, trapping and killing adult males decreased the re-depredation risk. At sheep farms, killing wolves was generally effective. Attempting to trap, regardless of the results, seemed more effective at reducing depredations than not trapping, suggesting that mere human activity near depredation sites might deter future depredations.

  13. Engineered female-specific lethality for control of pest Lepidoptera.

    Science.gov (United States)

    Jin, Li; Walker, Adam S; Fu, Guoliang; Harvey-Samuel, Timothy; Dafa'alla, Tarig; Miles, Andrea; Marubbi, Thea; Granville, Deborah; Humphrey-Jones, Nerys; O'Connell, Sinead; Morrison, Neil I; Alphey, Luke

    2013-03-15

    The sterile insect technique (SIT) is a pest control strategy involving the mass release of radiation-sterilized insects, which reduce the target population through nonviable matings. In Lepidoptera, SIT could be more broadly applicable if the deleterious effects of sterilization by irradiation could be avoided. Moreover, male-only release can improve the efficacy of SIT. Adequate methods of male-only production in Lepidoptera are currently lacking, in contrast to some Diptera. We describe a synthetic genetic system that allows male-only moth production for SIT and also replaces radiation sterilization with inherited female-specific lethality. We sequenced and characterized the doublesex (dsx) gene from the pink bollworm (Pectinophora gossypiella). Sex-alternate splicing from dsx was used to develop a conditional lethal genetic sexing system in two pest moths: the diamondback moth (Plutella xylostella) and pink bollworm. This system shows promise for enhancing existing pink bollworm SIT, as well as broadening SIT-type control to diamondback moth and other Lepidoptera.

  14. Lethal Mutagenesis of Hepatitis C Virus Induced by Favipiravir.

    Science.gov (United States)

    de Ávila, Ana I; Gallego, Isabel; Soria, Maria Eugenia; Gregori, Josep; Quer, Josep; Esteban, Juan Ignacio; Rice, Charles M; Domingo, Esteban; Perales, Celia

    2016-01-01

    Lethal mutagenesis is an antiviral approach that consists in extinguishing a virus by an excess of mutations acquired during replication in the presence of a mutagen. Here we show that favipiravir (T-705) is a potent mutagenic agent for hepatitis C virus (HCV) during its replication in human hepatoma cells. T-705 leads to an excess of G → A and C → U transitions in the mutant spectrum of preextinction HCV populations. Infectivity decreased significantly in the presence of concentrations of T-705 which are 2- to 8-fold lower than its cytotoxic concentration 50 (CC50). Passaging the virus five times in the presence of 400 μM T-705 resulted in virus extinction. Since T-705 has undergone advanced clinical trials for approval for human use, the results open a new approach based on lethal mutagenesis to treat hepatitis C virus infections. If proven effective for HCV in vivo, this new anti-HCV agent may be useful in patient groups that fail current therapeutic regimens.

  15. Killing Range: Explaining Lethality Variance within a Terrorist Organization.

    Science.gov (United States)

    Asal, Victor; Gill, Paul; Rethemeyer, R Karl; Horgan, John

    2015-04-01

    This paper presents an analysis of the Provisional Irish Republican Army's (PIRA) brigade level behavior during the Northern Ireland Conflict (1970-1998) and identifies the organizational factors that impact a brigade's lethality as measured via terrorist attacks. Key independent variables include levels of technical expertise, cadre age, counter-terrorism policies experienced, brigade size, and IED components and delivery methods. We find that technical expertise within a brigade allows for careful IED usage, which significantly minimizes civilian casualties (a specific strategic goal of PIRA) while increasing the ability to kill more high value targets with IEDs. Lethal counter-terrorism events also significantly affect a brigade's likelihood of killing both civilians and high-value targets but in different ways. Killing PIRA members significantly decreases IED fatalities but also significantly decreases the possibility of zero civilian IED-related deaths in a given year. Killing innocent Catholics in a Brigade's county significantly increases total and civilian IED fatalities. Together the results suggest the necessity to analyze dynamic situational variables that impact terrorist group behavior at the sub-unit level.

  16. An outbreak of lethal adenovirus infection among different otariid species.

    Science.gov (United States)

    Inoshima, Yasuo; Murakami, Tomoaki; Ishiguro, Naotaka; Hasegawa, Kazuhiro; Kasamatsu, Masahiko

    2013-08-30

    An outbreak of fatal fulminant hepatitis at a Japanese aquarium involved 3 otariids: a California sea lion (Zalophus californianus), a South African fur seal (Arctocephalus pusillus) and a South American sea lion (Otaria flavescens). In a span of about a week in February 2012, 3 otariids showed diarrhea and were acutely low-spirited; subsequently, all three animals died within a period of 3 days. Markedly increased aspartate amino transferase and alanine amino transferase activities were observed. Necrotic hepatitis and eosinophilic intranuclear inclusion bodies in liver hepatocytes and intestinal epithelial cells were observed in the South American sea lion on histological examination. Otarine adenovirus DNA was detected from the livers of all three animals by polymerase chain reaction and determination of the sequences showed that all were identical. These results suggest that a single otarine adenovirus strain may have been the etiological agent of this outbreak of fatal fulminant hepatitis among the different otariid species, and it may be a lethal threat to wild and captive otariids. This is the first evidence of an outbreak of lethal adenovirus infection among different otariid species.

  17. Detection and quantitation of infectious pancreatic necrosis virus by real-time reverse transcriptase-polymerase chain reaction using lethal and non-lethal tissue sampling.

    Science.gov (United States)

    Bowers, Robert M; Lapatra, Scott E; Dhar, Arun K

    2008-02-01

    Infectious pancreatic necrosis virus (IPNV) is a bisegmented double-stranded RNA virus belonging to the family Birnaviridae, genus Aquabirnavirus, which is a major viral pathogen of salmonid fish. The virus infects wild and cultured salmonids, causing high mortality in juvenile trout and salmon. A highly sensitive and specific real-time RT-PCR assay using the fluorogenic dye SYBR((R)) Green I was developed for the detection and quantitation of IPNV in rainbow trout (Oncorhynchus mykiss). Rainbow trout were infected experimentally with IPNV in the laboratory by injection or immersion and then pectoral fin, spleen, and head kidney samples were collected for analysis. The corresponding cDNA was synthesized using DNase I-treated total RNA and then real-time RT-PCR was performed using primers based on the IPNV non-structural protein gene, designated as either NS or VP4. Rainbow trout beta-actin and elongation factor 1alpha (EF-1alpha) genes were used as internal controls. Using real-time RT-PCR, the virus was successfully detected in pectoral fin, spleen, and head kidney tissue samples. The dissociation curves for each amplicon showed a single melting peak at 83, 81.5, and 84 degrees C for IPNV NS, trout beta-actin, and EF-1alpha genes, respectively. The amplicon size and nucleotide sequence was used to confirm the specificity of the products. Using a dilution series of in vitro transcribed RNA, IPNV was reliably detected down to 10 RNA copies and had a dynamic range up to 10(7) RNA copies. A time course assay, using immersion challenged samples, revealed that the virus could be detected in pectoral fin, spleen, and head kidney as early as 24h post-challenge. The average viral load in all three tissues increased over time, reaching its highest level at 21 days post-challenge, which was followed by a slight decrease at 28 days post-challenge. IPNV load in pectoral fin tissue was comparable to the viral load in spleen and head kidney tissues, indicating that pectoral fin

  18. Chemical Factors in Development and Transmission of Human Parasites.

    Science.gov (United States)

    PARASITES, *PREVENTIVE MEDICINE, *BIOCIDES, *REPELLENTS, HORMONES, TABLES(DATA), SCHISTOSOMA MANSONI, BRAZIL, PARASITIC DISEASES, DISEASE VECTORS, INSECT REPELLENTS, CHAGAS DISEASE, TRYPANOSOMA CRUZI .

  19. Exo-erythrocytic development of avian malaria and related haemosporidian parasites.

    Science.gov (United States)

    Valkiūnas, Gediminas; Iezhova, Tatjana A

    2017-03-03

    Avian malaria parasites (Plasmodium spp.) and related haemosporidians (Haemosporida) are responsible for diseases which can be severe and even lethal in avian hosts. These parasites cause not only blood pathology, but also damage various organs due to extensive exo-erythrocytic development all over the body, which is not the case during Plasmodium infections in mammals. However, exo-erythrocytic development (tissue merogony or schizogony) remains the most poorly investigated part of life cycle in all groups of wildlife haemosporidian parasites. In spite of remarkable progress in studies of genetic diversity, ecology and evolutionary biology of avian haemosporidians during the past 20 years, there is not much progress in understanding patterns of exo-erythrocytic development in these parasites. The purpose of this review is to overview the main information on exo-erythrocytic development of avian Plasmodium species and related haemosporidian parasites as a baseline for assisting academic and veterinary medicine researchers in morphological identification of these parasites using tissue stages, and to define future research priorities in this field of avian malariology. The data were considered from peer-reviewed articles and histological material that was accessed in zoological collections in museums of Australia, Europe and the USA. Articles describing tissue stages of avian haemosporidians were included from 1908 to the present. Histological preparations of various organs infected with the exo-erythrocytic stages of different haemosporidian parasites were examined. In all, 229 published articles were included in this review. Exo-erythrocytic stages of avian Plasmodium, Fallisia, Haemoproteus, Leucocytozoon, and Akiba species were analysed, compared and illustrated. Morphological characters of tissue stages that can be used for diagnostic purposes were specified. Recent molecular studies combined with histological research show that avian haemosporidians are more

  20. High host density favors greater virulence: a model of parasite-host dynamics based on multi-type branching processes

    CERN Document Server

    Borovkov, Konstantin; Rice, Timothy

    2011-01-01

    We use a multitype continuous time Markov branching process model to describe the dynamics of the spread of parasites of two types that can mutate into each other in a common host population. Instead of using a single virulence characteristic which is typical of most mathematical models for infectious diseases, our model uses a combination of two characteristics: lethality and transmissibility. This makes the model capable of reproducing the empirically observed fact that the increase in the host density can lead to the prevalence of the more virulent pathogen type. We provide some numerical illustrations and discuss the effects of the size of the enclosure containing the host population on the encounter rate in our model that plays the key role in determining what pathogen type will eventually prevail. We also present a multistage extension of the model to situations where there are several populations and parasites can be transmitted from one of them to another.