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Sample records for experimentally infected specific

  1. Gag- and env-specific serum antibodies in cats after natural and experimental infection with feline immunodeficiency virus.

    NARCIS (Netherlands)

    G.F. Rimmelzwaan (Guus); C.H.J. Siebelink (Kees); H. Broos; G.A. Drost; K. Weijer (Kees); R. van Herwijnen (Rob); A.D.M.E. Osterhaus (Albert)

    1994-01-01

    textabstractIn order to monitor the antibody response to feline immunodeficiency virus (FIV) in cats, following experimental and natural infection, enzyme-linked immunosorbent assays (ELISAs) were developed using recombinant env and gag proteins and p24-specific monoclonal antibodies. It was shown

  2. Specific detection of Neospora caninum oocysts in fecal samples from experimentally-infected dogs using the polymerase chain reaction.

    Science.gov (United States)

    Hill, D E; Liddell, S; Jenkins, M C; Dubey, J P

    2001-04-01

    Neospora caninum oocysts, passed in the feces of a definitive host (dog), were isolated, and genomic DNA was extracted. A polymerase cahin reaction (PCR) targeting the N. caninum-specific Nc 5 genomic sequence was performed using the isolated DNA. A synthesized competitor molecule containing part of the Nc 5 sequence was included in the assay as a check against false-negative PCR results and to quantify N. caninum oocyst DNA in fecal samples. A standard curve of the ratio of fluorescence intensity of PCR-amplified competitor to that of oocyst DNA was constructed to compare oocyst equivalents from fecal samples containing unknown numbers of N. caninum oocysts and to assess the sensitivity of the assay. The specificity of the assay was determined using the Nc 5-specific primers in PCR assays against other parasites likely to be found in canine feces. Genomic DNA sequences from the canine coccidians Hammondia heydorni, Cryptosporidium parvum, Sarcocystis cruzi, S. tenella, and Isospora ohioensis and the canine helminth parasites Strongyloides stercoralis, Toxocara canis, Dipylidium caninum, and Ancylostoma caninum were not amplified. In addition, genomic DNA sequences from oocysts of coccidian parasites that might contaminate dog feces, such as Hammondia hammondi, Toxoplasma gondii, or Eimeria tenella, were not amplified in the PCR assay. The assay should be useful in epidemiological surveys of both domestic and wild canine hosts and in investigations of oocyst biology in experimental infections.

  3. Changes in serum Strongylus vulgaris-specific antibody concentrations in response to anthelmintic treatment of experimentally-infected foals

    Directory of Open Access Journals (Sweden)

    Martin Krarup Nielsen

    2015-07-01

    Full Text Available Strongylus vulgaris is the most pathogenic nematode parasite of horses. Its extensive migration in the mesenteric blood vessels can lead to life-threatening intestinal infarctions. Recent work has shown that this parasite is still identified among managed horse populations. A serum enzyme-linked immunosorbent assay (ELISA has been developed for the detection of migrating larvae of S. vulgaris. Previous work has documented an increase in ELISA values following larvicidal treatment with ivermectin and suggested that the target parasite antigen is primarily produced by the later larval stages. The aim of this study was to experimentally inoculate cohorts of foals with S. vulgaris, and then compare ELISA responses to early or later ivermectin treatments. Fifteen foals were held in confinement and infected orally with ~ 25 S. vulgaris third-stage larvae on days 0, 7, 14, and 21. Foals were weaned on Day 43 and turned out to a pasture not previously grazed by horses. Foals remained at pasture continuously until the study was terminated on Day 196. On Day 55, foals were randomly allocated to three treatment groups of five each. Group 1 received ivermectin on Day 56, Group 2 received ivermectin on Day 112, and Group 3 foals served as untreated controls. Serum and fecal samples were collected at 28-day intervals throughout the study. Serum samples were analyzed with the S. vulgaris-specific ELISA and fecal samples were processed for fecal egg counting. The ELISA values of Group 1 foals were significantly lower than Groups 2 or 3 on days 140-196. Both treated groups exhibited increased ELISA values following ivermectin treatment. Results indicate that the target diagnostic antigen is produced throughout the course of arterial infection with S. vulgaris, but that an early ivermectin treatment can reduce the cumulative antigen produced over the course of an infection.

  4. Changes in Serum Strongylus Vulgaris-Specific Antibody Concentrations in Response to Anthelmintic Treatment of Experimentally Infected Foals.

    Science.gov (United States)

    Nielsen, Martin Krarup; Scare, Jessica; Gravatte, Holli Sullivan; Bellaw, Jennifer Lynn; Prado, Julio C; Reinemeyer, Craig Robert

    2015-01-01

    Strongylus vulgaris is the most pathogenic nematode parasite of horses. Its extensive migration in the mesenteric blood vessels can lead to life-threatening intestinal infarctions. Recent work has shown that this parasite is still identified among managed horse populations. A serum enzyme-linked immunosorbent assay (ELISA) has been developed for the detection of migrating larvae of S. vulgaris. Previous work has documented an increase in ELISA values following larvicidal treatment with ivermectin and suggested that the target parasite antigen is primarily produced by the later larval stages. The aim of this study was to experimentally inoculate cohorts of foals with S. vulgaris, and then compare ELISA responses to early or later ivermectin treatments. Fifteen foals were held in confinement and infected orally with ~25 S. vulgaris third-stage larvae on Days 0, 7, 14, and 21. Foals were weaned on Day 43 and turned out to a pasture not previously grazed by horses. Foals remained at pasture continuously until the study was terminated on Day 196. On Day 55, foals were randomly allocated to three treatment groups of five each. Group 1 received ivermectin on Day 56, Group 2 received ivermectin on Day 112, and Group 3 foals served as untreated controls. Serum and fecal samples were collected at 28-day intervals throughout the study. Serum samples were analyzed with the S. vulgaris-specific ELISA and fecal samples were processed for fecal egg counting. The ELISA values of Group 1 foals were significantly lower than Groups 2 or 3 on Days 140-196. Both treated groups exhibited increased ELISA values following ivermectin treatment. Results indicate that the target diagnostic antigen is produced throughout the course of arterial infection with S. vulgaris, but that an early ivermectin treatment can reduce the cumulative antigen produced over the course of an infection.

  5. Prevention of diarrhoea using pathogen specific monoclonal antibodies in an experimental enterotoxigenic E. coli infection in germfree piglets

    NARCIS (Netherlands)

    Geus, de B.; Harmsen, M.; Zijderveld, van F.

    1998-01-01

    In the present study we describe the effect of oral application of mAB specific for ETEC F4(ac) fimbriae in an experimental ETEC challenge model in neonatal germfree piglets. The results show that mAB, specific for different F4(ac) epitopes protect animals against ETEC specific pathology. Moreover,

  6. Evaluation of {sup 99m}Tc-UBI 29-41 scintigraphy for specific detection of experimental Staphylococcus aureus prosthetic joint infections

    Energy Technology Data Exchange (ETDEWEB)

    Sarda-Mantel, Laure; Meulemans, Alain; Vrigneaud, Jean-Marc; Raguin, Olivier; Lebtahi, Rachida; Guludec, Dominique Le [Universite Denis Diderot-Paris 7, UMR S773, Paris (France); Service de Medecine Nucleaire, AP-HP, Groupe Hospitalier Bichat-Beaujon, Paris (France); INSERM, U773, Paris (France); Saleh-Mghir, Azzam [Universite Versailles-St-Quentin, EA 3647, Garches (France); Welling, Mick M. [Leiden University Medical Center (LUCM), Department of Radiology, Section of Nuclear Medicine, Leiden (Netherlands); Hervatin, Florence [Universite Denis Diderot-Paris 7, UMR S773, Paris (France); CEA, DSV/DRM/SHFJ, Orsay (France); Martet, Genevieve [Universite Denis Diderot-Paris 7, UMR S773, Paris (France); INSERM, U773, Paris (France); Chau, Francoise [Universite Denis Diderot-Paris 7, UMR S773, Paris (France); Universite Denis Diderot Paris 7, EA 3964, Paris (France)

    2007-08-15

    {sup 99m}Tc-UBI 29-41 (UBI), an antimicrobial peptide, specifically targets bacteria. We tested the ability of UBI to discriminate between infected and uninfected prosthetic joints using a rabbit model previously validated. Left knee arthroplasty was performed on 20 New Zealand rabbits, then 10{sup 7} cfu of S. aureus (n = 12) or sterile saline (n = 8) was injected into the joint. On days 9 and 20 after surgery, planar UBI scintigraphy was performed in six infected and four uninfected rabbits, 1 h and 4 h p.i. (150 MBq), on a gamma camera. Operated-to-normal knee activity ratio (ONKR) was calculated on each scintigram. Then, after sacrifice, tissue samples of both knees were counted in a gamma counter. One rabbit injected with sterile saline had cutaneous infection at sacrifice and was excluded from analysis. ONKR was higher in infected than in uninfected animals 4 h p.i. 20 days after surgery: 1.75 {+-} 0.48 vs 1.13 {+-} 0.11, p = 0.04. From 1 h to 4 h p.i., ONKR increased in 9/12 infected and 0/7 uninfected animals. According to UBI uptake intensity and kinetics, scintigraphy was truly positive in all infected cases on day 9 and in four of six infected cases on day 20. It was truly negative in two of three sterile inflamed prosthetic knees on day 9, and in all cases on day 20. Biodistribution studies revealed increased UBI uptake in periprosthetic tissues in all animals 9 days after surgery, and only in infected animals on day 20. In this experimental study, {sup 99m}Tc-UBI 29-41 scintigraphy permitted the early detection of acute prosthetic joint infection, and exclusion of infection in chronic sterile prosthetic joint inflammation. (orig.)

  7. Evaluation of 99mTc-UBI 29-41 scintigraphy for specific detection of experimental Staphylococcus aureus prosthetic joint infections

    International Nuclear Information System (INIS)

    Sarda-Mantel, Laure; Meulemans, Alain; Vrigneaud, Jean-Marc; Raguin, Olivier; Lebtahi, Rachida; Guludec, Dominique Le; Saleh-Mghir, Azzam; Welling, Mick M.; Hervatin, Florence; Martet, Genevieve; Chau, Francoise

    2007-01-01

    99m Tc-UBI 29-41 (UBI), an antimicrobial peptide, specifically targets bacteria. We tested the ability of UBI to discriminate between infected and uninfected prosthetic joints using a rabbit model previously validated. Left knee arthroplasty was performed on 20 New Zealand rabbits, then 10 7 cfu of S. aureus (n = 12) or sterile saline (n = 8) was injected into the joint. On days 9 and 20 after surgery, planar UBI scintigraphy was performed in six infected and four uninfected rabbits, 1 h and 4 h p.i. (150 MBq), on a gamma camera. Operated-to-normal knee activity ratio (ONKR) was calculated on each scintigram. Then, after sacrifice, tissue samples of both knees were counted in a gamma counter. One rabbit injected with sterile saline had cutaneous infection at sacrifice and was excluded from analysis. ONKR was higher in infected than in uninfected animals 4 h p.i. 20 days after surgery: 1.75 ± 0.48 vs 1.13 ± 0.11, p = 0.04. From 1 h to 4 h p.i., ONKR increased in 9/12 infected and 0/7 uninfected animals. According to UBI uptake intensity and kinetics, scintigraphy was truly positive in all infected cases on day 9 and in four of six infected cases on day 20. It was truly negative in two of three sterile inflamed prosthetic knees on day 9, and in all cases on day 20. Biodistribution studies revealed increased UBI uptake in periprosthetic tissues in all animals 9 days after surgery, and only in infected animals on day 20. In this experimental study, 99m Tc-UBI 29-41 scintigraphy permitted the early detection of acute prosthetic joint infection, and exclusion of infection in chronic sterile prosthetic joint inflammation. (orig.)

  8. Human immunodeficiency virus type 1 neutralization epitope with conserved architecture elicits early type-specific antibodies in experimentally infected chimpanzees

    NARCIS (Netherlands)

    Goudsmit, J.; Debouck, C.; Meloen, R. H.; Smit, L.; Bakker, M.; Asher, D. M.; Wolff, A. V.; Gibbs, C. J.; Gajdusek, D. C.

    1988-01-01

    Chimpanzees are susceptible to infection by divergent strains of human immunodeficiency virus type 1 (HIV-1), none of which cause clinical or immunological abnormalities. Chimpanzees were inoculated with one of four strains of HIV-1: human T-lymphotropic virus (HTLV) type IIIB, lymphadenopathy virus

  9. The time course of the specific antibody response by various ELISAs in pigs experimentally infected with Toxoplasma gondii

    DEFF Research Database (Denmark)

    Lind, Peter; Haugegaard, J.; Wingstrand, Anne

    1997-01-01

    With the aim of developing routine serological tests for monitoring the Toxoplasma infection status of Danish swine herds, four ELISAs based on tachyzoite antigen were set up: (1) an indirect ELISA for IgG-antibody; (2) a blocking ELISA for antibody to the membrane antigen, P-30; (3) an indirect ...

  10. Experimental chronic Pseudomonas aeruginosa lung infection in rats. Non-specific stimulation with LPS reduces lethality as efficiently as specific immunization

    DEFF Research Database (Denmark)

    Lange, K H; Hougen, H P; Høiby, N

    1995-01-01

    In a rat model of chronic Pseudomonas aeruginosa lung infection mimicking cystic fibrosis, we investigated the possibility of preventing chronic lung inflammation or decreasing the progression of the infection. We compared the lethality, pathology, bacterial clearance, and immunogenicity after...... with either E. coli LPS or P. aeruginosa sonicate. Four and two weeks prior to challenge other rats were vaccinated with either E. coli LPS or P. aeruginosa sonicate. Controls did not receive any stimulation or vaccination. The lethality after challenge was lower in rats stimulated with E. coli LPS (p = 0...... but not to prevent the chronic P. aeruginosa lung infection and inflammation caused by alginate-embedded bacteria....

  11. Somatic cell count and milk neutrophil viability of dairy heifers with specific CXCR1 genotypes following experimental intramammary infection with Staphylococcus chromogenes originating from milk.

    Science.gov (United States)

    Verbeke, Joren; Piccart, Kristine; Piepers, Sofie; Van Poucke, Mario; Peelman, Luc; De Visscher, Anneleen; De Vliegher, Sarne

    2015-06-01

    Previous observational studies suggest an association between polymorphism c.980A>G in the CXCR1 gene, encoding the chemokine (C-X-C motif) receptor 1, and the innate immunity and infection status of the mammary gland. Mammary glands of eight Holstein heifers were experimentally infected with a Staphylococcus chromogenes isolate originating from a chronic intramammary infection (IMI) to study differences between CXCR1 genotypes c.980AG and c.980GG. Quarters from heifers with genotypes c.980AG and c.980GG developed subclinical mastitis but showed differences in the early response at 6-18 h post challenge. Bacterial count at 18 h post challenge tended to be higher in quarters from c.980AG heifers compared to c.980GG heifers. Somatic cell count (SCC) was higher at 6 h post challenge and tended to be higher at 9 h post challenge in c.980AG heifers compared to c.980GG heifers. Milk production decreased similarly. Milk neutrophils of c.980AG heifers showed more apoptosis at 9 h post challenge and tended to show more necrosis at 6, 9 and 12 h post challenge than c.980GG heifers. Differences were less pronounced in the later stage (>18 h) of infection. The results demonstrate that CXCR1 polymorphism can influence SCC and milk neutrophil viability following experimental IMI. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Detection of infectious bursal disease virus in various lymphoid tissues of experimentally infected specific pathogen free chickens by different reverse transcription polymerase chain reaction assays

    DEFF Research Database (Denmark)

    Kabell, Susanne; Handberg, Kurt; Kusk, Mette

    2005-01-01

    Infectious bursal disease (IBD) is a worldwide distributed immunosuppressive viral disease in young chickens, controlled by vaccination. Emergence of several strains of IBD virus (IBDV) has created a demand for strain-specific diagnostic tools. In the present experiment, five different reverse...... included vaccine strain D78, classical strain Faragher 52/70, and the very virulent Danish strain DK01 The presence of the virus infection was confirmed by histopathologic evaluation of bursa lesions. The largest number of positive samples was obtained with a strain-specific two-step multiplex (MPX) RT...

  13. Experimental rhinovirus infection in volunteers.

    Science.gov (United States)

    Bardin, P G; Sanderson, G; Robinson, B S; Holgate, S T; Tyrrell, D A

    1996-11-01

    Experimental viral disease studies in volunteers have clarified many aspects of the pathogenesis of human viral disease. Recently, interest has focused on rhinovirus-associated asthma exacerbations, and new volunteer studies have suggested that airway responsiveness (AR) is enhanced during a cold. For scientific, ethical and safety reasons, it is important to use validated methods for the preparation of a virus inoculum and that the particular virological characteristics and host responses should not be altered. We have prepared a new human rhinovirus (HRV) inoculum using recent guidelines and assessed whether disease characteristics (for example, severity of colds or changes in AR) were retained. Studies were conducted in 25 clinically healthy volunteers using a validated HRV inoculum in the first 17 and a new inoculum in the subsequent eight subjects. Severity of cold symptoms, nasal wash albumin levels and airway responsiveness were measured, and the new inoculum was prepared from nasal washes obtained during the cold. The new inoculum was tested using standard virological and serological techniques, as well as a polymerase chain reaction for Mycoplasma pneumoniae. No contaminating viruses or organisms were detected and the methods suggested were workable. Good clinical colds developed in 20 of the 25 subjects and median symptom scores were similar in the validated and new inoculum groups (18 and 17.5, respectively; p=0.19). All subjects shed virus, and there were no differences noted in viral culture scores, nasal wash albumin and rates of seroconversion in the two groups. Although airway responsiveness increased in both groups (p=0.02 and p=0.05), the degree of change was similar. We have performed experimental rhinovirus infection studies and demonstrated similar clinical disease in two inoculum groups. Amplified airway responsiveness was induced; continuing studies will define the mechanisms and suggest modes of treatment.

  14. Blood biochemistry responses of chickens experimentally infected ...

    African Journals Online (AJOL)

    This study investigated the blood biochemistry responses of cockerels experimentally infected with a velogenic Newcastle disease virus (NDV) strain, KUDU 113. One hundred Isa white cockerels were used for the study. The cockerels were obtained at day-old and randomly divided into groups A- vaccinated and infected, ...

  15. Macrophage specific drug delivery in experimental leishmaniasis.

    Science.gov (United States)

    Basu, Mukul Kumar; Lala, Sanchaita

    2004-09-01

    Macrophage-specific delivery systems are the subject of much interest nowadays, because of the fact that macrophages act as host cells for many parasites and bacteria, which give rise to outbreak of so many deadly diseases(eg. leishmaniasis, tuberculosis etc.) in humans. To combat these deadly diseases initially macrophage specific liposomal delivery system were thought of and tested in vivo against experimental leishmaniasis in hamsters using a series of indigenous or synthetic antileishmanial compounds and the results were critically discussed. In vitro testing was also done against macrophages infected with Leishmania donovani, the causative agent for visceral leishmaniasis. The common problem of liposome therapy being their larger size, stability and storage, non-ionic surfactant vesicles, niosomes were prepared, for their different drug distribution and release characteristics compared to liposomes. When tested in vivo, the retention capacity of niosomes was found to be higher than that of liposomes due to the absence of lipid molecules and their smaller size. Thus the therapeutic efficacy of certain antileishmanial compounds was found to be better than that in the liposomal form. The niosomes, being cheaper, less toxic, biodegradable and non-immunogenic, were considered for sometime as suitable alternatives to liposomes as drug carriers. Besides the advent of other classical drugs carriers(e.g. neoglycoproteins), the biggest challenge came from polymeric delivery vehicles, specially the polymeric nanoparticles which were made of cost effective biodegradable polymers and different natural polymers. Because of very small size and highly stable nature, use of nanoparticles as effective drug carriers has been explored in experimental leishmaniasis using a series of antileishmanial compounds, both of indigenous and synthetic origin. The feasibility of application in vivo, when tested for biological as well as for other physicochemical parameters, the polymeric

  16. Experimental Salmonella typhimurium infections in rats. I

    DEFF Research Database (Denmark)

    Hougen, H P; Jensen, E T; Klausen, B

    1989-01-01

    The course of experimentally induced Salmonella typhimurium infection was studied in three groups of inbred LEW rats: homozygous +/+, athymic rnu/rnu and isogeneic thymus-grafted rnu/rnu rats. In the first experiment the animals were inoculated intraperitoneally with 10(8) bacteria and all animals...... became severely septicemic and died within a week of inoculation, irrespective of presence or absence of thymus. In the second experiment the animals were inoculated with 10(6) bacteria, and both euthymic and thymus-grafted animals responded with high titres of anti bacterial antibodies while these were...... very low in the athymic nude animals. Polyclonal antibody production was only observed in the euthymic animals and only regarding IgG. Athymic rats were not able to clear the infection, while the thymus-grafted animals reacted like euthymic rats: Very few animals housed the bacteria four weeks after...

  17. Co-incubation with IL-18 potentiates antigen-specific IFN-γ response in a whole-blood stimulation assay for measurement of cell-mediated immune responses in pigs experimentally infected with Lawsonia intracellularis

    DEFF Research Database (Denmark)

    Riber, Ulla; Boesen, Henriette Toft; Jakobsen, Jeanne Toft

    2011-01-01

    The whole-blood interferon-gamma (IFN-γ) assay is a quantitative in-vitro assay for a direct read out of Ag-specific cell-mediated immune (CMI) responses to infectious diseases. The IFN-γ assay is robust in severe intracellular infections like Brucella or mycobacteria, but more difficult to evalu......The whole-blood interferon-gamma (IFN-γ) assay is a quantitative in-vitro assay for a direct read out of Ag-specific cell-mediated immune (CMI) responses to infectious diseases. The IFN-γ assay is robust in severe intracellular infections like Brucella or mycobacteria, but more difficult...

  18. Formal specification is an experimental science

    Energy Technology Data Exchange (ETDEWEB)

    Bjorner, D. [Technical Univ., Lyngby (Denmark)

    1992-09-01

    Traditionally, abstract models of large, complex systems have been given in free-form mathematics, combining - often in ad-hoc, not formally supported ways - notions from the disciplines of partial differential equations, functional analysis, mathematical statistics, etc. Such models have been very useful for assimilation of information, analysis (investigation), and prediction (simulation). These models have, however, usually not been helpful in deriving computer representations of the modelled systems - for the purposes of computerized monitoring and control, Computing science, concerned with how to construct objects that can exist within the computer, offers ways of complementing, and in some cases, replacing or combining traditional mathematical models. Formal, model-, as well as property-oriented, specifications in the styles of denotational (respectively, algebraic semantics) represent major approaches to such modelling. In this expository, discursive paper we illustrate what we mean by model-oriented specifications of large, complex technological computing systems. The three modelling examples covers the introvert programming methodological subject of SDEs: software development environments, the distributed computing system subject of wfs`s: (transaction) work flow systems, and the extrovert subject of robots: robotics! the thesis is, just as for mathematical modelling, that we can derive much understanding, etc., from experimentally creating such formally specified models - on paper - and that we gain little in additionally building ad-hoc prototypes. Our models are expressed in a model-oriented style using the VDM specification language Meta-IV In this paper the models only reflect the {open_quotes}data modelling{close_quotes} aspects. We observe that such data models are more easily captured in the model-oriented siyle than in the algebraic semantics property-oriented style which originally was built of the abstraction of operations. 101 refs., 4 figs.

  19. Schmallenberg virus experimental infection of sheep

    DEFF Research Database (Denmark)

    Wernike, Kerstin; Hoffmann, Bernd; Bréard, Emmanuel

    2013-01-01

    production and diarrhoea for a few days. However, the knowledge about clinical signs and pathogenesis in adult sheep is limited.In the present study, adult sheep of European domestic breeds were inoculated with SBV either as cell culture grown virus or as virus with no history of passage in cell cultures...... 3–5 days by real-time RT-PCR. In total, 13 out of 30 inoculated sheep became RNAemic, with the highest viral load in animals inoculated with virus from low cell culture passaged or the animal passaged material. Contact animals remained negative throughout the study. One RNAemic sheep showed...... results in subclinical infection, transient RNAemia and a specific antibody response. Maintenance of viral RNA in the lymphoreticular system is observed for an extended period....

  20. Persistence of specific antibody response in different experimental infections of mice with Toxocara canis larvae Persistência da resposta humoral em camundongos experimentalmente infectados com larvas de Toxocara canis

    Directory of Open Access Journals (Sweden)

    Pedro Paulo Chieffi

    1995-06-01

    Full Text Available Anti-Toxocara antibody production and persistence were studied in experimental infections of BALB/c mice, according to three different schedules: Group I (GI - 25 mice infected with 200 T. canis eggs in a single dose; Group II (GII 25 mice infected with 150 T. canis eggs given in three occasions, 50 in the 1st, 50 in the 5th and 50 in the 8th days; Group III (GIII - 25 mice also infected with 150 T. canis eggs, in three 50 eggs portions given in the 1st, 14th and 28th days. A 15 mice control group (GIV was maintained without infection. In the 30th, 50th, 60th, 75th, 105th and 180th post-infection days three mice of the GI, GII and GIII groups and two mice of the control group had been sacrificed and exsanguinated for sera obtention. In the 360th day the remainder mice of the four groups were, in the same way, killed and processed. The obtained sera were searched for the presence of anti-Toxocara antibodies by an ELISA technique, using T. canis larvae excretion-secretion antigen. In the GI and GII, but not in the GIII, anti-Toxocara antibodies had been found, at least, up to the 180th post-infection day. The GIII only showed anti-Toxocara antibodies, at significant level, in the 30th post-infection day.Estudou-se a cinética de anticorpos anti-Toxocara em camundongos BALB/c infectados experimentalmente segundo três esquemas: Grupo I (GI: 25 camundongos infectados com dose única de 200 ovos embrionados de T. canis; grupo II (GII: 25 camundongos infectados com 150 ovos embrionados de T. canis, divididos em três doses de 50 ovos, administrados no 1º, 5º e 8º dias; Grupo III (GIII: 25 camundongos infectados com 150 ovos embrionados de T. canis, administrados em três doses de 50 ovos no 1º, 14º e 28º dias. Um grupo de 15 camundongos foi mantido nas mesmas condições, porém sem infecção, constituindo o grupo controle (GIV. No 30º, 50º, 60º, 75º, 105º e 180º dias pós-infecção três camundongos dos grupos GI, GII e GIII e dois do

  1. Experimental infection of Rickettsia parkeri in the Rhipicephalus microplus tick.

    Science.gov (United States)

    Cordeiro, Matheus Dias; de Azevedo Baêta, Bruna; Cepeda, Patricia Barizon; Teixeira, Rafaella Câmara; Ribeiro, Carla Carolina Dias Uzedo; de Almeida Valim, Jaqueline Rodrigues; Pinter, Adriano; da Fonseca, Adivaldo Henrique

    2018-01-01

    This study aimed to evaluate, by means of artificial feeding, the interaction between a pathogenic rickettsia and the hard tick R. microplus. We used partially engorged females fed on calves free of Rickettsia spp. Group 1 (G1), containing 20 ticks, was fed bovine blood only. Group 2 (G2), containing 20 ticks, was fed blood containing uninfected VERO cells, and group 3 (G3), containing 40 ticks, was fed blood containing VERO cells infected with Rickettsia parkeri. Biological parameters of the non-parasitic phase and a possible bacterial transmission to the tick eggs and to guinea pigs were evaluated. At the end of oviposition, all G3 females were PCR-positive for genes specific for the genus Rickettsia. Although no guinea pigs were infected, the experimental infection of R. microplus by R. parkeri caused a deleterious effect on the oviposition and provided the first report of transovarian transmission of rickettsia in this tick. Copyright © 2017 Elsevier GmbH. All rights reserved.

  2. Comparative haematological changes in experimentally infected ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-07-04

    Jul 4, 2008 ... However, disease such as animal trypanosomiasis possess a great risk to their ... The severity of the infection is influenced by a number of factors .... agrees with a similar work in which a significant fall in packed cell volume ... Heat production, body temperature and body posture in West. African dwarf goats ...

  3. Species-specific nested PCR as a diagnostic tool for Brucella ovis infection in rams

    Directory of Open Access Journals (Sweden)

    L.F. Costa

    2013-02-01

    Full Text Available The aim of the present study was to evaluate a species-specific nested PCR based on a previously described species-specific PCR for detection of B. ovis in semen and urine samples of experimentally infected rams. The performance of the species-specific nested PCR was compared with the results of a genus-specific PCR. Fourteen rams were experimentally infected with the Brucella ovis REO 198 strain and samples of semen and urine were collected every week up to 180 days post infection. Out of 83 semen samples collected, 42 (50.6% were positive for the species-specific nested PCR, and 23 (27.7% were positive for the genus-specific PCR. Out of 75 urine samples, 49 (65.3% were positive for the species-specific nested PCR, whereas 11 (14.6% were genus-specific PCR positive. Species-specific nested PCR was significantly more sensitive (P<0.001 than the genus-specific PCR in semen and urine from experimentally infected rams. In conclusion, the species-specific nested PCR developed in this study may be used as a diagnostic tool for the detection of B. ovis in semen and urine samples from suspected rams.

  4. Infections in orthopaedic surgery : clinical and experimental studies

    NARCIS (Netherlands)

    Vogely, Henri Charles

    2000-01-01

    The diagnostic difficulties, variability in outcome and the heterogeinity of the problem of orthopaedic infections stimulated the author to a study of the literature, and several clinical and experimental studies. The diagnosis prosthesis-related infection can only be reached with an acceptable

  5. Pathogenesis of natural and experimental Pseudorabies virus infections in dogs.

    Science.gov (United States)

    Zhang, Letian; Zhong, Cheng; Wang, Jushi; Lu, Zijie; Liu, Lei; Yang, Wanlian; Lyu, Yanli

    2015-03-18

    Since late 2011, cases of suspected canine pseudorabies have increased in north China with the outbreak of swine pseudorabies in the same area, but the pathogenesis of canine Pseudorabies virus (PRV) infections in China is poorly understood. In this study, we investigated the pathogenesis of canine pseudorabies. The pathological changes in 13 dogs that died of natural PRV infections (confirmed by pathogen detection) during 2011-2013 in Beijing were evaluated. An experimental study was also conducted in which healthy adult beagle dogs were administered PRV isolate BJ-YT by subcutaneous injection. The dog tissues were subjected to gross and microscopic examinations and immunohistochemical analysis and the dogs' serum cardiac troponin-I (cTn-I) was measured. Systemic hemorrhage and/or congestion were the most marked pathological changes in both the naturally and experimentally PRV-infected dogs. Macroscopically, the major lesions consisted of petechiae and ecchymoses in both the endocardium and epicardium, thrombi in the mitral valves, hemorrhage in the lungs and thymus, and incomplete contraction of the spleen. Microscopically, the major histopathological findings were systemic hemorrhage and congestion, nonsuppurative ganglioneuritis (in the experimentally infected dogs, unexamined in the naturally PRV-infected dogs), brainstem encephalitis (in the naturally infected dogs), necrosis or exudation in the myocardium, and lymphoid depletion in many lymphoid organs and tissues. Viral antigens were only detected in the brainstems and peripheral ganglia of the infected dogs. Serum cTn-I was significantly higher in the experimentally PRV-infected dogs with myocardial lesions than in the dogs without myocardial lesions. Based on these results, we conclude that virally induced systemic hemorrhage, peripheral nervous system pathology, and/or cardiac injury can individually or collectively cause death in PRV-infected dogs. The respiratory signs of the disease are attributed to

  6. Effect of Exposure Dose on Ichthyophonus Prevalence and Infection Intensity in Experimentally Infected Rainbow Trout, Oncorhynchus mykiss.

    Science.gov (United States)

    Kocan, Richard; LaPatra, Scott

    2016-02-01

    This study describes the effect of increasing exposure dose on Ichthyophonus prevalence and infection intensity in experimentally infected rainbow trout, Oncorhynchus mykiss. Specific-pathogen free trout were exposed per os to increasing numbers of Ichthyophonus schizonts obtained from naturally infected donor fish, then sampled after 30 and 60 days post-exposure. Both in vitro explant culture and histology revealed that as the number of schizonts per dose increased there was a proportionate increase in the number of infected fish, as well as an increase in the number of infected organs; parasite density in individual infected organs also increased with dose. Explant culture revealed that all fish exposed to the highest dose (≥2,080 schizonts) became infected, while only 67% of those exposed to the intermediate dose (1,040-1,153 schizonts) were Ichthyophonus-positive after 60 days; Ichthyophonus was not detected in fish exposed to the 2 lowest doses (≤280 schizonts). Histologic examination of individual infected organs also revealed increasing infection prevalence and parasite density in response to exposure to increasing numbers of Ichthyophonus schizonts.

  7. Experimental porcine cysticercosis using infected beetles with Taenia solium eggs.

    Science.gov (United States)

    Gomez-Puerta, Luis A; Garcia, Hector H; Gonzalez, Armando E

    2018-07-01

    Beetles are intermediate hosts for human and animal parasites, and several beetle species have been shown to carry Taenia eggs. An experimental porcine cysticercosis infection model was developed using beetles (Ammophorus rubripes) infected with Taenia solium eggs and then using these beetles for oral pig challenge. A total of 18 three months-old Landrace pigs were divided in four groups. Pigs from groups 1, 2, and 3 (n = 6 pigs per group) were challenged with one, three, and six beetles infected with T. solium eggs, containing approximately 52, 156 or 312 eggs respectively. Pigs were necropsied 12 weeks after infection to assess the presence of T. solium metacestode. Porcine cysticercosis by T. solium was produced in 17 out of 18 pigs (94.4%) challenged with infected beetles, all infected pigs had viable cysts. Only one pig from group 1 was negative to the presence of cysts. The median number of metacestodes per pig in groups 1, 2, and 3 were 2 (range 0-71), 26 (range 5-33) and 40 cysts (range 4-111), respectively. Experimental porcine cysticercosis infection is consistently obtained using beetles as mechanical vectors for T. solium eggs. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Primary infection protects pigs against re-infection with Lawsonia intracellularis in experimental challenge studies

    DEFF Research Database (Denmark)

    Riber, Ulla; Hvass, Henriette Cordes; Boutrup, Torsten Snogdal

    2011-01-01

    In two separate trials previous termpigsnext term were experimentally infected with previous termLawsonia intracellularisnext term at 5–6 weeks of age followed by antibiotic treatment and resolution of the previous termprimary infection and then renext term-inoculated at 12–13 weeks of age. A tre...

  9. Infectivity of Trichinella papuae for experimentally infected red foxes (Vulpes vulpes)

    DEFF Research Database (Denmark)

    Webster, P.; Malakauskas, A.; Kapel, C. M O

    2002-01-01

    To evaluate infectivity for carnivores as well as other biological characteristics of the newly described Trichinella papuae, eight red foxes were experimentally infected with the parasite. Five weeks after inoculation, T. papuae larvae were recovered from nine different muscle types. The larvae...

  10. Highly pathogenic avian influenza virus (H5N1) in experimentally infected adult mute swans.

    Science.gov (United States)

    Kalthoff, Donata; Breithaupt, Angele; Teifke, Jens P; Globig, Anja; Harder, Timm; Mettenleiter, Thomas C; Beer, Martin

    2008-08-01

    Adult, healthy mute swans were experimentally infected with highly pathogenic avian influenza virus A/Cygnus cygnus/Germany/R65/2006 subtype H5N1. Immunologically naive birds died, whereas animals with preexisting, naturally acquired avian influenza virus-specific antibodies became infected asymptomatically and shed virus. Adult mute swans are highly susceptible, excrete virus, and can be clinically protected by preexposure immunity.

  11. Primary peak and chronic malaria infection levels are correlated in experimentally infected great reed warblers.

    Science.gov (United States)

    Asghar, Muhammad; Westerdahl, Helena; Zehtindjiev, Pavel; Ilieva, Mihaela; Hasselquist, Dennis; Bensch, Staffan

    2012-09-01

    Malaria parasites often manage to maintain an infection for several months or years in their vertebrate hosts. In humans, rodents and birds, most of the fitness costs associated with malaria infections are in the short initial primary (high parasitaemia) phase of the infection, whereas the chronic phase (low parasitaemia) is more benign to the host. In wild birds, malaria parasites have mainly been studied during the chronic phase of the infection. This is because the initial primary phase of infection is short in duration and infected birds with severe disease symptoms tend to hide in sheltered places and are thus rarely caught and sampled. We therefore wanted to investigate the relationship between the parasitaemia during the primary and chronic phases of the infection using an experimental infection approach. We found a significant positive correlation between parasitaemia in the primary peak and the subsequent chronic phase of infection when we experimentally infected great reed warblers (Acrocephalus arundinaceus) with Plasmodium ashfordi. The reason for this association remains to be understood, but might arise from individual variation in exoerythrocytic parasite reservoirs in hosts, parasite antigenic diversity and/or host genetics. Our results suggest that the chronic phase parasitaemia can be used to qualitatively infer the parasitaemia of the preceding and more severe primary phase, which is a very important finding for studies of avian malaria in wild populations.

  12. Experimental reproduction of an Enterococcus cecorum infection in Pekin ducks.

    Science.gov (United States)

    Jung, Arne; Metzner, Martin; Köhler-Repp, Dagmar; Rautenschlein, Silke

    2013-12-01

    Enterococcus cecorum (EC) was thus far only known as a pathogen for broilers and broiler breeders. Recently there was evidence of EC field outbreaks in Pekin duck flocks in Germany. In this study we experimentally reproduced an EC infection in Pekin ducks. At 12 days post hatch, groups of Pekin ducks were infected orally, via the thoracic air sac or intravenously with 1.5 × 10(9) colony-forming units (CFU) of EC per bird or via the air sac with 8.5 × 10(5) or 8.5 × 10(7) CFU per bird. Ducks of the intravenously infected group showed 100% mortality after 2 days post infection. The air sac inoculated high-dose group exhibited a mortality rate of 67%. Birds that were infected with 8.5 × 10(5) and 8.5 × 10(7) CFU showed 6.7% mortality after 7 days post infection. Dead birds displayed pneumonia, airsacculitis, pericarditis and splenitis and EC was re-isolated from these organs. Surviving birds of all groups apart from the orally infected ducks demonstrated clinical signs such as huddling, reduced mobility and diarrhoea. Furthermore, they showed gross pathological lesions including airsacculitis and splenitis and lower bodyweights than the control group at necropsy on days 7, 14 and 21 post infection. The present study clearly confirms that EC is pathogenic for Pekin ducks after experimental infection via the intravenous route or the respiratory tract. EC therefore has to be considered as an emerging avian pathogen not only in broilers but also in Pekin ducks.

  13. Comparative Experimental Infection Study in Dogs with Ehrlichia canis, E. chaffeensis, Anaplasma platys and A. phagocytophilum.

    Science.gov (United States)

    Nair, Arathy D S; Cheng, Chuanmin; Ganta, Chanran K; Sanderson, Michael W; Alleman, Arthur R; Munderloh, Ulrike G; Ganta, Roman R

    2016-01-01

    Dogs acquire infections with the Anaplasmataceae family pathogens, E. canis, E. chaffeensis, E. ewingii, A. platys and A. phagocytophilum mostly during summer months when ticks are actively feeding on animals. These pathogens are also identified as causing diseases in people. Despite the long history of tick-borne diseases in dogs, much remains to be defined pertaining to the clinical and pathological outcomes of infections with these pathogens. In the current study, we performed experimental infections in dogs with E. canis, E. chaffeensis, A. platys and A. phagocytophilum. Animals were monitored for 42 days to evaluate infection-specific clinical, hematological and pathological differences. All four pathogens caused systemic persistent infections detectible throughout the 6 weeks of infection assessment. Fever was frequently detected in animals infected with E. canis, E. chaffeensis, and A. platys, but not in dogs infected with A. phagocytophilum. Hematological differences were evident in all four infected groups, although significant overlap existed between the groups. A marked reduction in packed cell volume that correlated with reduced erythrocytes and hemoglobin was observed only in E. canis infected animals. A decline in platelet numbers was common with E. canis, A. platys and A. phagocytophilum infections. Histopathological lesions in lung, liver and spleen were observed in all four groups of infected dogs; infection with E. canis had the highest pathological scores, followed by E. chaffeensis, then A. platys and A. phagocytophilum. All four pathogens induced IgG responses starting on day 7 post infection, which was predominantly comprised of IgG2 subclass antibodies. This is the first detailed investigation comparing the infection progression and host responses in dogs after inoculation with four pathogens belonging to the Anaplasmataceae family. The study revealed a significant overlap in clinical, hematological and pathological changes resulting from the

  14. Salmonella Enteritidis experimental infection in chickens: Effects of ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-10-20

    Oct 20, 2008 ... challenge dose of Salmonella Enteritidis on detection of specific immunoglobulin G (IgG) ... Two groups of specific-pathogen-free chickens were infected ... Since chickens may be exposed to variable quantities ... A second group of 8 hens was orally .... where presence of serum antibodies by most birds that.

  15. Cardiac complication after experimental human malaria infection: a case report

    Directory of Open Access Journals (Sweden)

    Druilhe Pierre

    2009-12-01

    Full Text Available Abstract A 20 year-old healthy female volunteer participated in a clinical Phase I and IIa safety and efficacy trial with candidate malaria vaccine PfLSA-3-rec adjuvanted with aluminium hydroxide. Eleven weeks after the third and last immunization she was experimentally infected by bites of Plasmodium falciparum-infected mosquitoes. When the thick blood smear became positive, at day 11, she was treated with artemether/lumefantrine according to protocol. On day 16 post-infection i.e. two days after completion of treatment, she woke up with retrosternal chest pain. She was diagnosed as acute coronary syndrome and treated accordingly. She recovered quickly and her follow-up was uneventful. Whether the event was related to the study procedures such as the preceding vaccinations, malaria infection or antimalarial drugs remains elusive. However, the relation in time with the experimental malaria infection and apparent absence of an underlying condition makes the infection the most probable trigger. This is in striking contrast, however, with the millions of malaria cases each year and the fact that such complication has never been reported in the literature. The rare occurrence of cardiac events with any of the preceding study procedures may even support a coincidental finding. Apart from acute coronary syndrome, myocarditis can be considered as a final diagnosis, but the true nature and patho-physiological explanation of the event remain unclear.

  16. Analysis of experimental mink enteritis virus infection in mink: in situ hybridization, serology, and histopathology

    DEFF Research Database (Denmark)

    Uttenthal, Åse; Larsen, S; Lund, E

    1990-01-01

    Strand-specific hybridization probes were used in in situ hybridization studies to localize cells containing mink enteritis virus (MEV) virion DNA or MEV replicative-form DNA and mRNA. Following the experimental MEV infection of 3-month-old unvaccinated mink, a significant increase in serum antib...

  17. Tc-99m labeled Sparfloxacin: A specific infection imaging agent

    International Nuclear Information System (INIS)

    Singh, A.K.; Verma, J.; Bhatnagar, A.; Ali, A.

    2003-01-01

    Radiolabeled antibiotics are being used for the specific diagnosis of infection by exploiting their specific binding properties to the bacterial component, thereby making it possible to differentiate infection from sterile lesions. A new radiopharmaceutical, Tc-99m Sparfloxacin has been developed for infection imaging. Sparfloxacin is a quinolone based broad-spectrum antibiotic, which is more potent than Ciprofloxacin. Radiolabeling of Sparfloxacin with Tc-99m was standardized using direct labeling protocol. Labeling efficiency, in-vitro and in-vivo stability, blood kinetics and organ distribution studies (in balb/c mice and New Zealand White Rabbits at different time interval up to 24hrs) were carried out. Biological activity of Sparfloxacin after its labeling with Tc-99m was evaluated with S.aureus using Peptone water (DIFCO) as media. Turpentine oil (100 μl) in left thigh and S.aureus (100μl of 3x10 7 cells) in right thigh were injected intramuscularly to create sterile and infective inflammation respectively in six New Zealand white rabbits. The localization kinetics of the radiolabeled complex were studied in the animal model by injecting 70-75MBq of Tc-99m Sparfloxacin intravenously in the ear of rabbit and the images were taken with a Gamma-camera (ECIL) at different post-injection time intervals. Standardized protocol produced >95% labeled complex. About 8% of tracer leached out at 24 hrs when incubated in serum at 37 0 C, confirming high stability of the complex. Blood clearance in rabbit revealed biphasic pattern and 50% of the complex clears from the blood within 5 min. Biodistribution studies in balb/c mice showed hepatobiliary route of excretion. Presence of insignificant amount of tracer at 24 hrs in the stomach confirmed high in vivo stability of the complex. Imaging in rabbits showed significant concentration of tracer in lesions with infection. Typical imaging patterns revealed initial accumulation of radiotracer in both sterile inflammatory

  18. [Specific iatrogenic risks to patients with HIV infection].

    Science.gov (United States)

    De Tournemire, R; Yeni, P

    1994-01-01

    Human immunodeficiency virus-infected patients are exposed to more or less specific iatrogenic diseases. The main characteristics of the risks encountered in this field are described: drug intolerance, mostly to sulfamethoxazole-trimethoprim, is extremely frequent; nucleoside analogue antiviral toxicity is reminiscent of that of chemotherapy; nosocomial infections, in general, are more prominent than in HIV-non infected patients. Intravenous line infections are particularly frequent, but these devices are necessary for prolonged intravenous therapies such as anti-CMV treatment of parenteral nutrition. An improved understanding of different etiopathogenic mechanisms and a better approach of the toxicity/efficacy ratio for each treatment would allow to reduce the excessive morbidity due to iatrogenicity.

  19. Oxidative stress in rats experimentally infected by Sporothrix schenckii.

    Science.gov (United States)

    Castro, Verônica S P; Da Silva, Aleksandro S; Thomé, Gustavo R; Wolkmer, Patrícia; Castro, Jorge L C; Costa, Márcio M; Graça, Dominguita L; Oliveira, Daniele C; Alves, Sydney H; Schetinger, Maria R C; Lopes, Sonia T A; Stefani, Lenita M; Azevedo, Maria I; Baldissera, Matheus D; Andrade, Cinthia M

    2017-06-01

    The aim of this study was to evaluate whether oxidative stress occurs in rats experimentally infected by Sporothrix schenckii, and its possible effect on disease pathogenesis. Thirty rats were divided into two groups: the group A (uninfected, n = 18) and the group B (infected by S. schenckii, n=21). Blood samples were collected on days 15, 30 and 40 post-infection (PI). At each sampling time, six rats of the group A, and seven of the group B were bled. TBARS (thiobarbituric acid reactive substances) levels in serum samples were measured to evaluate lipid peroxidation. In addition, catalase (CAT) and superoxide dismutase (SOD) activities, known as biomarkers of antioxidants levels, were verified in whole blood. Seric pro-inflammatory cytokine levels were measured (IFN-γ, TNF-α, and IL-6), which showed that these inflammatory mediators were at higher levels in the infected rats (P sporotrichosis showed significantly higher (p sporotrichosis is a likely mechanism for redox imbalance, and consequently cause the oxidative stress in experimentally infected rats. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Age-specific prevalence of cervical human papillomavirus infection ...

    African Journals Online (AJOL)

    This cross-sectional study describes the age-specific prevalence of human papillomavirus (HPV) infection and cytological abnormalities among this urban and peri-urban population. Method. Over the period March 2009 - September 2011, 1 524 women attending public sector primary healthcare clinics were invited to

  1. Protein Spesifik Cairan Kista Cysticercus bovis pada Sapi Bali yang Diinfeksi dengan Taenia saginata (SPECIFIC PROTEIN OF CYSTICERCUS BOVIS CYST FLUID ON BALI CATTLE EXPERIMENTALLY INFECTED WITH TAENIA SAGINATA

    Directory of Open Access Journals (Sweden)

    Nyoman Sadra Dharmawan

    2013-08-01

    Full Text Available Cysticercus bovis is the larval stage of Taenia saginata, the bovine tapeworm. The infection of thislarval in cattle musculature causes Bovine cysticercosis or Cysticercosis bovis.  Bovine cysticercosis is foundworldwide, but mostly in developing countries, where unhygienic conditions, poor cattle managementpractices, and the absence of meat inspection are common.  The adult Taenia infection in man is referredto as taeniasis.  Taenia saginata taeniasis is also found almost all over the world.  The prevalence ofTaenia saginata taeniasis has reported up to 27.5% in Gianyar Bali. In order to control the diseases,vaccination against the larvae stages in cattle of Taenia saginata may play an important role in controllingthe disease in the endemic regions.  The aims of the present study were to prepare and to investigate theimmunogenic protein as vaccine candidate for controlling  Cysticercus bovis infection in in Bali cattle.Cysticercus protein from the cyst fluid was firstly used to immunize mice and the mice sera were thencollected. Cysticercus proteins then analyzed using sodium dodecyl sulfate-gel electrophoresis (SDS-PAGE.All cysticercus proteins were then visualized by Commasie blue staining. The proteins were also transferredonto nitrocellulose membrane and the immunogenic proteins were visualized by Western Blotting usingimmune sera raised in mice.  By Commasie blue staining, a total of 17 proteins were detected with themolecular weight of 14,86 kDa -122,40 kDa from the smallest to the largest. As many as 7 immunogenicproteins with the molecular weights of 16.81 kDa; 19.22 kDa; 20.98 kDa; 27.41 kDa; 34.02 kDa; 38.31 kDa;and 54.94kDa were detected.

  2. Strain specific transcriptional response in Mycobacterium tuberculosis infected macrophages

    Directory of Open Access Journals (Sweden)

    Koo Mi-Sun

    2012-01-01

    Full Text Available Abstract Background Tuberculosis (TB, a bacterial infection caused by Mycobacterium tuberculosis (Mtb remains a significant health problem worldwide with a third of the world population infected and nearly nine million new cases claiming 1.1 million deaths every year. The outcome following infection by Mtb is determined by a complex and dynamic host-pathogen interaction in which the phenotype of the pathogen and the immune status of the host play a role. However, the molecular mechanism by which Mtb strains induce different responses during intracellular infection of the host macrophage is not fully understood. To explore the early molecular events triggered upon Mtb infection of macrophages, we studied the transcriptional responses of murine bone marrow-derived macrophages (BMM to infection with two clinical Mtb strains, CDC1551 and HN878. These strains have previously been shown to differ in their virulence/immunogenicity in the mouse and rabbit models of pulmonary TB. Results In spite of similar intracellular growth rates, we observed that compared to HN878, infection by CDC1551 of BMM was associated with an increased global transcriptome, up-regulation of a specific early (6 hours immune response network and significantly elevated nitric oxide production. In contrast, at 24 hours post-infection of BMM by HN878, more host genes involved in lipid metabolism, including cholesterol metabolism and prostaglandin synthesis were up-regulated, compared to infection with CDC1551. In association with the differences in the macrophage responses to infection with the 2 Mtb strains, intracellular CDC1551 expressed higher levels of stress response genes than did HN878. Conclusions In association with the early and more robust macrophage activation, intracellular CDC1551 cells were exposed to a higher level of stress leading to increased up-regulation of the bacterial stress response genes. In contrast, sub-optimal activation of macrophages and induction of

  3. Effects of Experimental Sarcocystis neurona-Induced Infection on Immunity in an Equine Model

    Directory of Open Access Journals (Sweden)

    S. Rochelle Lewis

    2014-01-01

    Full Text Available Sarcocystis neurona is the most common cause of Equine Protozoal Myeloencephalitis (EPM, affecting 0.5–1% horses in the United States during their lifetimes. The objective of this study was to evaluate the equine immune responses in an experimentally induced Sarcocystis neurona infection model. Neurologic parameters were recorded prior to and throughout the 70-day study by blinded investigators. Recombinant SnSAG1 ELISA for serum and CSF were used to confirm and track disease progression. All experimentally infected horses displayed neurologic signs after infection. Neutrophils, monocytes, and lymphocytes from infected horses displayed significantly delayed apoptosis at some time points. Cell proliferation was significantly increased in S. neurona-infected horses when stimulated nonspecifically with PMA/I but significantly decreased when stimulated with S. neurona compared to controls. Collectively, our results suggest that horses experimentally infected with S. neurona manifest impaired antigen specific response to S. neurona, which could be a function of altered antigen presentation, lack of antigen recognition, or both.

  4. Effects of Experimental Sarcocystis neurona-Induced Infection on Immunity in an Equine Model.

    Science.gov (United States)

    Lewis, S Rochelle; Ellison, Siobhan P; Dascanio, John J; Lindsay, David S; Gogal, Robert M; Werre, Stephen R; Surendran, Naveen; Breen, Meghan E; Heid, Bettina M; Andrews, Frank M; Buechner-Maxwell, Virginia A; Witonsky, Sharon G

    2014-01-01

    Sarcocystis neurona is the most common cause of Equine Protozoal Myeloencephalitis (EPM), affecting 0.5-1% horses in the United States during their lifetimes. The objective of this study was to evaluate the equine immune responses in an experimentally induced Sarcocystis neurona infection model. Neurologic parameters were recorded prior to and throughout the 70-day study by blinded investigators. Recombinant SnSAG1 ELISA for serum and CSF were used to confirm and track disease progression. All experimentally infected horses displayed neurologic signs after infection. Neutrophils, monocytes, and lymphocytes from infected horses displayed significantly delayed apoptosis at some time points. Cell proliferation was significantly increased in S. neurona-infected horses when stimulated nonspecifically with PMA/I but significantly decreased when stimulated with S. neurona compared to controls. Collectively, our results suggest that horses experimentally infected with S. neurona manifest impaired antigen specific response to S. neurona, which could be a function of altered antigen presentation, lack of antigen recognition, or both.

  5. Heterogeneous infectiousness in guinea pigs experimentally infected with Trypanosoma cruzi.

    Science.gov (United States)

    Castillo-Neyra, Ricardo; Borrini Mayorí, Katty; Salazar Sánchez, Renzo; Ancca Suarez, Jenny; Xie, Sherrie; Náquira Velarde, Cesar; Levy, Michael Z

    2016-02-01

    Guinea pigs are important reservoirs of Trypanosoma cruzi, the causative parasite of Chagas disease, and in the Southern Cone of South America, transmission is mediated mainly by the vector Triatoma infestans. Interestingly, colonies of Triatoma infestans captured from guinea pig corrals sporadically have infection prevalence rates above 80%. Such high values are not consistent with the relatively short 7-8 week parasitemic period that has been reported for guinea pigs in the literature. We experimentally measured the infectious periods of a group of T. cruzi-infected guinea pigs by performing xenodiagnosis and direct microscopy each week for one year. Another group of infected guinea pigs received only direct microscopy to control for the effect that inoculation by triatomine saliva may have on parasitemia in the host. We observed infectious periods longer than those previously reported in a number of guinea pigs from both the xenodiagnosis and control groups. While some guinea pigs were infectious for a short time, other "super-shedders" were parasitemic up to 22 weeks after infection, and/or positive by xenodiagnosis for a year after infection. This heterogeneity in infectiousness has strong implications for T. cruzi transmission dynamics and control, as super-shedder guinea pigs may play a disproportionate role in pathogen spread. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  6. Humoral immune response and spreading of Encephalitozoon cuniculi infection in experimentally infected ponies

    Czech Academy of Sciences Publication Activity Database

    Wagnerová, Pavla; Sak, Bohumil; Květoňová, Dana; Maršálek, M.; Langerová, I.; Kváč, Martin

    2013-01-01

    Roč. 197, 1-2 (2013), s. 1-6 ISSN 0304-4017 Institutional support: RVO:60077344 Keywords : Ponies * Encephalitozoon cuniculi genotype II * PCR * Antibodies * Experimental infection Subject RIV: EC - Immunology Impact factor: 2.545, year: 2013

  7. Early weight development of goats experimentally infected with Mycobacterium avium subsp. paratuberculosis.

    Directory of Open Access Journals (Sweden)

    Alyssa N Malone

    Full Text Available Johne's disease is an infectious chronic inflammatory bowel disease in ruminants. The key factor for the management of this disease is an early positive diagnosis. Unfortunately, most diagnostics detect animals with Johne's disease in the clinical stage with positive serology and/or positive fecal cultures. However, for effective management of the disease within herds, it is important to detect infected animals as early as possible. This might only be possible with the help of parameters not specific for Johne's disease but that give an early indication for chronic infections such as weight development. Here we report our findings on the development of total body weight and weight gain during the first six months of goats experimentally infected to induce Johne's disease. Twenty dairy goat kids age 2 to 5 days were included in this study. Goats were divided into two groups: a negative control group and a positive infected group. The weight was obtained weekly throughout the study. Goats of the positive group were infected at the age of seven weeks. We detected significant changes in weight gain and total body weight as early as one week after infection. Differences are significant throughout the six month time period. Weight as a non-specific parameter should be used to monitor infection especially in studies on Johne's disease using the goat model. Our study suggests that goats with Johne's disease have a reduced weight gain and reduced weight when compared with healthy goats of the same age.

  8. Immunoglobulin subclass in experimental murine Toxocara cati infection

    Directory of Open Access Journals (Sweden)

    Kusnoto

    2017-11-01

    Full Text Available Aim: The aim of this study was to detect specific immunoglobulin (Ig that could be used to determine monoclonal antibody in conjugate-making an effort for the indirect enzyme-linked immunosorbent assay (ELISA diagnostic kit of toxocariasis in human. Materials and Methods: The study was conducted to assess the Ig profile, based on ELISA-isotyping, in mice infected with second stage larvae eggs of Toxocara cati. The optical density values of anti-T. cati mice serum IgG subclasses were analyzed by applying ANOVA factorial. Results: The specific IgG subclass in mice infected with T. cati mice was found to be IgG2β. Conclusion: Subclass of IgG, especially IgG2β, can provide leads about the use of the monoclonal antibody in conjugate making an effort for the indirect ELISA diagnostic kit.

  9. Experimental Andes virus infection in deer mice: characteristics of infection and clearance in a heterologous rodent host.

    Directory of Open Access Journals (Sweden)

    Jessica R Spengler

    Full Text Available New World hantaviruses can cause hantavirus cardiopulmonary syndrome with high mortality in humans. Distinct virus species are hosted by specific rodent reservoirs, which also serve as the vectors. Although regional spillover has been documented, it is unknown whether rodent reservoirs are competent for infection by hantaviruses that are geographically separated, and known to have related, but distinct rodent reservoir hosts. We show that Andes virus (ANDV of South America, carried by the long tailed pygmy rice rat (Oligoryzomys longicaudatus, infects and replicates in vitro and in vivo in the deer mouse (Peromyscus maniculatus, the reservoir host of Sin Nombre virus (SNV, found in North America. In experimentally infected deer mice, viral RNA was detected in the blood, lung, heart and spleen, but virus was cleared by 56 days post inoculation (dpi. All of the inoculated deer mice mounted a humoral immune response by 14 dpi, and produced measurable amounts of neutralizing antibodies by 21 dpi. An up-regulation of Ccl3, Ccl4, Ccl5, and Tgfb, a strong CD4⁺ T-cell response, and down-regulation of Il17, Il21 and Il23 occurred during infection. Infection was transient with an absence of clinical signs or histopathological changes. This is the first evidence that ANDV asymptomatically infects, and is immunogenic in deer mice, a non-natural host species of ANDV. Comparing the immune response in this model to that of the immune response in the natural hosts upon infection with their co-adapted hantaviruses may help clarify the mechanisms governing persistent infection in the natural hosts of hantaviruses.

  10. Experimental Infections of Oryzomys couesi with Sympatric Arboviruses from Mexico

    Science.gov (United States)

    Deardorff, Eleanor R.; Forrester, Naomi L.; Travassos da Rosa, Amelia P.; Estrada-Franco, Jose G.; Navarro-Lopez, Roberto; Tesh, Robert B.; Weaver, Scott C.

    2010-01-01

    Coues rice rat (Oryzomys couesi), a species abundant throughout Central America, was evaluated experimentally for the ability to serve as an amplifying host for three arboviruses: Patois (Bunyaviridae, Orthobunyavirus), Nepuyo (Orthobunyavirus), and Venezuelan equine encephalitis virus subtype ID (Togaviridae, Alphavirus). These three viruses have similar ecologies and are known to co-circulate in nature. Animals from all three cohorts survived infection and developed viremia with no apparent signs of illness and long-lasting antibodies. Thus, O. couesi may play a role in the general maintenance of these viruses in nature. PMID:20134016

  11. Experimental study on active specific immunotherapy modified with irradiation

    International Nuclear Information System (INIS)

    Imanaka, Kazufumi; Ogawa, Yasuhiro; Gose, Kyuhei; Imajo, Yoshinari; Kumura, Shuji

    1982-01-01

    We have already reported that the effectiveness of active specific immunotherapy using irradiated tumor cells and infiltrating mononuclear cells which were separated from the topical tumor tissue 7 days after irradiation of 2,000 rad in experimental study. The present study was designed to investigate the effect of non-specific immunopotentiator PS-K combined with active specific immunotherapy. Female C3H/He mice aged 12 weeks were inoculated 4 x 10 6 MM 46 tumor cells in the right hind paws and received local electron irradiation with the dose of 3,000 rad on the 5th day after irradiation. Active specific immunotherapy was performed on the 12th day, and daily dose of 200 mg/kg of PS-K was injected intraperitoneally from the 6th day to the 10th day. The inhibition of the tumor growth and the elongation of survival period were noted in the group which received active specific immunotherapy combined with non-specific immunopotentiator, PS-K compared with the active specific immunotherapy alone. (author)

  12. Parasite-specific IL-4 responses in Ascaris suum and Trichuris suis-infected pigs evaluated by ELISPOT

    DEFF Research Database (Denmark)

    Steenhard, N. R.; Kringel, H.; Roepstorff, A.

    2007-01-01

    method is a valuable tool for future experimental settings as it enables repeated and parasite-specific measurement of IL-4 at protein level when investigating, for example, immunomodulatory properties of helminths. Furthermore, the method could be used to identify specific parasite antigens inducing IL......The objective of the present study was to develop an ELISPOT method to measure parasite-specific IL-4 producing cells during experimental Ascaris suum and Trichuris suis infections in pigs. In many experimental settings it is useful to be able to measure changes in specifically induced cytokines...

  13. Improving Diagnosis and Treatment of Staphylococcus aureus Infections : Experimental Studies

    NARCIS (Netherlands)

    S. van den Berg (Sanne)

    2015-01-01

    markdownabstract__Abstract__ Staphylococcus aureus is an opportunistic pathogen that causes a variety of infections, ranging from mild skin infections like furuncles and impetigo, to severe, lifethreatening infections including endocarditis, osteomyelitis and pneumonia. Invasive infections are

  14. Technetium-99m stannous pyrophosphate imaging of experimental infective endocarditis

    International Nuclear Information System (INIS)

    Riba, A.L.; Downs, J.; Thakur, M.L.; Gottschalk, A.; Andriole, V.T.; Zaret, B.L.

    1978-01-01

    Technetium-99m stannous pyrophosphate (/sup 99m/Tc-PYP) cardiac scintigraphy was performed in 15 rabbits with experimental Streptococcus sanguis aortic-valve infective endocarditis. The animals were imaged five to seven days after the administration of bacteria, and in each case abnormal accumulation of the tracer was visualized in the region of the aortic valve. Three types of cardiac scintigraphic patterns were demonstrated: focal, multifocal, and extensive, each correlating well with the anatomical extent of the lesion as defined by gross pathology. Tissue distribution studies demonstrated a 30 +- 5.3 (mean +- SEM) fold excess of radionuclide uptake in the infective endocarditis lesion compared with that of normal myocardium. Imaging of excised hearts from four animals showed an excellent correlation with in vivo imaging as well as gross pathology. Five animals with nonbacterial thrombotic aortic valve endocarditis demonstrated similar scintigraphic and tissue distribution results. In contrast, four normal animals failed to demonstrate abnormal /sup 99m/Tc-PYP cardiac scintigrams or tissue uptake. This study demonstrates that /sup 99m/Tc-PYP cardiac scintigraphy is a sensitive technique to detect experimental aortic valve endocarditis

  15. Immunodiagnosis of systemic aspergillosis. I. Antigenemia detected by radioimmunoassay in experimental infection

    International Nuclear Information System (INIS)

    Weiner, M.H.; Coats-Stephen, M.

    1979-01-01

    Because systemic aspergillosis is difficult to diagnose ante mortem, a study to improve immunodiagnosis was undertaken in a rabbit model of disseminated infection. We found that the predominant humoral response of infected animals was directed against four Aspergillus antigens identified by crossed immunoelectrophoresis. One of these antigens, a cell-wall carbohydrate, was purified by gel-filtration chromatography and was used to develop a radiommunoassay. The sensitivity of this assay was increased by testing for serum-bound antigen as well as for free antigen. When the sensitivity of the RIA was evaluated in the animal model, antigenemia was detected in 78% of 51 rabbits with disseminated infection and ante mortem in 86% of 42 rabbits with lethal infection. By contrast, with immunoprecipitin analysis only eight of 51 rabbits were positive for antigen, and six of 51 rabbits were positive for Aspergillus antibody. The specificity of the RIA was also tested. Negative controls for antigen included sera from 76 normal rabbits and sera from 25 rabbits with systemic candidiasis. The Candida control group is pertinent because 48% of these rabbits had specific Candida antigenemia detected by a mannan RIA. This study demonstrates that Aspergillus antigenemia occurs during the course of experimental disseminated aspergillosis and illustrates the potential of an Aspergillus antigen RIA for sensitive, specific immunodiagnosis of human infections

  16. An experimental model of mycobacterial infection under corneal flaps

    Directory of Open Access Journals (Sweden)

    C.B.D. Adan

    2004-07-01

    Full Text Available In order to develop a new experimental animal model of infection with Mycobacterium chelonae in keratomileusis, we conducted a double-blind prospective study on 24 adult male New Zealand rabbits. One eye of each rabbit was submitted to automatic lamellar keratotomy with the automatic corneal shaper under general anesthesia. Eyes were immunosuppressed by a single local injection of methyl prednisolone. Twelve animals were inoculated into the keratomileusis interface with 1 µl of 10(6 heat-inactivated bacteria (heat-inactivated inoculum controls and 12 with 1 µl of 10(6 live bacteria. Trimethoprim drops (0.1%, w/v were used as prophylaxis for the surgical procedure every 4 h (50 µl, qid. Animals were examined by 2 observers under a slit lamp on the 1st, 3rd, 5th, 7th, 11th, 16th, and 23rd postoperative days. Slit lamp photographs were taken to document clinical signs. Animals were sacrificed when corneal disease was detected and corneal samples were taken for microbiological analysis. Eleven of 12 experimental rabbits developed corneal disease, and M. chelonae could be isolated from nine rabbits. Eleven of the 12 controls receiving a heat-inactivated inoculum did not develop corneal disease. M. chelonae was not isolated from any of the control rabbits receiving a heat-inactivated inoculum, or from the healthy cornea of control rabbits. Corneal infection by M. chelonae was successfully induced in rabbits submitted to keratomileusis. To our knowledge, this is the first animal model of M. chelonae infection following corneal flaps for refractive surgery to be described in the literature and can be used for the analysis of therapeutic responses.

  17. SPECIFIC CONSTITUTIONAL FEATURES OF CHILDREN INFECTED WITH TUBERCULOSIS

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    Yu. A. Yarovaya

    2017-01-01

    Full Text Available In order to define specific constitutional features of the children infected with tuberculosis 222 children in the age from 1 to 14 years old have been examined: 106 children with active tuberculosis; 54 children with remaining post-tuberculosis changes; 62 children infected with tuberculous mycobacteria. The following types of diatheses were identified: lymphohypoplastic, allergic, neuroarthritic, exudative-catarrhal. It has been found out that among those with active tuberculosis the children suffering from lymphohypoplastic and neuroarthritic diatheses prevail (17.0 ± 3.7%, and allergic diathesis is less common (10.4 ± 3.0% cases. Children with lymphohypoplastic diathesis have a complicated course of tuberculosis (27.8 ± 10.6% and more intensive intoxication syndrome (55.6 ± 11.7%. The frequency of allergic diathesis is higher in the children with remaining post-tuberculosis changes (29.6 ± 6.2% and those infected with tuberculosis (33.8 ± 6.1% compared to children with active tuberculosis (10.4 ± 3.0%.

  18. Salmonella enterica serovar-specific transcriptional reprogramming of infected cells.

    Science.gov (United States)

    Hannemann, Sebastian; Galán, Jorge E

    2017-07-01

    Despite their high degree of genomic similarity, different Salmonella enterica serovars are often associated with very different clinical presentations. In humans, for example, the typhoidal S. enterica serovar Typhi causes typhoid fever, a life-threatening systemic disease. In contrast, the non-typhoidal S. enterica serovar Typhimurium causes self-limiting gastroenteritis. The molecular bases for these different clinical presentations are incompletely understood. The ability to re-program gene expression in host cells is an essential virulence factor for typhoidal and non-typhoidal S. enterica serovars. Here, we have compared the transcriptional profile of cultured epithelial cells infected with S. Typhimurium or S. Typhi. We found that both serovars stimulated distinct transcriptional responses in infected cells that are associated with the stimulation of specific signal transduction pathways. These specific responses were associated with the presence of a distinct repertoire of type III secretion effector proteins. These observations provide major insight into the molecular bases for potential differences in the pathogenic mechanisms of typhoidal and non-typhoidal S. enterica serovars.

  19. Salmonella enterica serovar-specific transcriptional reprogramming of infected cells.

    Directory of Open Access Journals (Sweden)

    Sebastian Hannemann

    2017-07-01

    Full Text Available Despite their high degree of genomic similarity, different Salmonella enterica serovars are often associated with very different clinical presentations. In humans, for example, the typhoidal S. enterica serovar Typhi causes typhoid fever, a life-threatening systemic disease. In contrast, the non-typhoidal S. enterica serovar Typhimurium causes self-limiting gastroenteritis. The molecular bases for these different clinical presentations are incompletely understood. The ability to re-program gene expression in host cells is an essential virulence factor for typhoidal and non-typhoidal S. enterica serovars. Here, we have compared the transcriptional profile of cultured epithelial cells infected with S. Typhimurium or S. Typhi. We found that both serovars stimulated distinct transcriptional responses in infected cells that are associated with the stimulation of specific signal transduction pathways. These specific responses were associated with the presence of a distinct repertoire of type III secretion effector proteins. These observations provide major insight into the molecular bases for potential differences in the pathogenic mechanisms of typhoidal and non-typhoidal S. enterica serovars.

  20. Transcriptomic study of 39 ostreid herpesvirus 1 genes during an experimental infection.

    Science.gov (United States)

    Segarra, Amélie; Faury, Nicole; Pépin, Jean-François; Renault, Tristan

    2014-06-01

    Massive mortality outbreaks have been reported in France since 2008 among Pacific oysters, Crassostrea gigas, with the detection of a particular OsHV-1 variant called μVar. Virus infection can be induced in healthy spat in experimental conditions allowing to better understand the disease process, including viral gene expression. Although gene expression of other herpesviruses has been widely studied, we provide the first study following viral gene expression of OsHV-1 over time. In this context, an in vivo transcriptomic study targeting 39 OsHV-1 genes was carried out during an experimental infection of Pacific oyster spat. For the first time, several OsHV-1 mRNAs were detected by real-time PCR at 0 h, 2 h, 4 h, 18 h, 26 h and 42 h post-injection. Several transcripts were detected at 2h post-infection and at 18 h post-infection for all selected ORFs. Quantification of virus gene expression at different times of infection was also carried out using an oyster housekeeping gene, Elongation factor. Developing an OsHV-1-specific reverse transcriptase real time PCR targeting 39 viral gene appears a new tool in terms of diagnosis and can be used to complement viral DNA detection in order to monitor viral replication. Copyright © 2014. Published by Elsevier Inc.

  1. Experimental infections with Mycoplasma agalactiae identify key factors involved in host-colonization.

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    Eric Baranowski

    Full Text Available Mechanisms underlying pathogenic processes in mycoplasma infections are poorly understood, mainly because of limited sequence similarities with classical, bacterial virulence factors. Recently, large-scale transposon mutagenesis in the ruminant pathogen Mycoplasma agalactiae identified the NIF locus, including nifS and nifU, as essential for mycoplasma growth in cell culture, while dispensable in axenic media. To evaluate the importance of this locus in vivo, the infectivity of two knock-out mutants was tested upon experimental infection in the natural host. In this model, the parental PG2 strain was able to establish a systemic infection in lactating ewes, colonizing various body sites such as lymph nodes and the mammary gland, even when inoculated at low doses. In these PG2-infected ewes, we observed over the course of infection (i the development of a specific antibody response and (ii dynamic changes in expression of M. agalactiae surface variable proteins (Vpma, with multiple Vpma profiles co-existing in the same animal. In contrast and despite a sensitive model, none of the knock-out mutants were able to survive and colonize the host. The extreme avirulent phenotype of the two mutants was further supported by the absence of an IgG response in inoculated animals. The exact role of the NIF locus remains to be elucidated but these data demonstrate that it plays a key role in the infectious process of M. agalactiae and most likely of other pathogenic mycoplasma species as many carry closely related homologs.

  2. Testing the sensitivity of Nested PCR method to detect Aspergillus fumigates in experimentally infected Sputum samples

    International Nuclear Information System (INIS)

    Ramadan, A.; Soukkaria, S.

    2013-01-01

    Fungal infections caused by Aspergillus species generally are occupying a second place among invasive fungal infections in the world, especially A. fumigatus, which is considered the main cause of invasive Aspergillosis (IA). Although IA rarely infects immunocompetent individuals, however, it can lead to death in immunocompromised patients. Therefore, it is necessary to diagnose the infection early in order to treat the disease efficiently. However, the conventional diagnostic tools, currently used to detect infections, has low sensitivity and reliability. Polymerase chain reaction (PCR) technology distribution as a molecular and high sensitive technology has allowed us to make comparative study between sensitivity of traditional currently used diagnostic method and Nested-PCR, the result of the study of sputum samples that experimentally infected with different concentrations of A.fumigatus spores ramping from 10 to10 6 spore/ml, have high sensitivity and specificity of Nested-PCR in detecting the lower concentrations, comparing with traditional diagnostic method (culture on Sabouraud media) that were negative in all concetrations. (author)

  3. Tupaia belangeri as an experimental animal model for viral infection.

    Science.gov (United States)

    Tsukiyama-Kohara, Kyoko; Kohara, Michinori

    2014-01-01

    Tupaias, or tree shrews, are small mammals that are similar in appearance to squirrels. The morphological and behavioral characteristics of the group have been extensively characterized, and despite previously being classified as primates, recent studies have placed the group in its own family, the Tupaiidae. Genomic analysis has revealed that the genus Tupaia is closer to humans than it is to rodents. In addition, tupaias are susceptible to hepatitis B virus and hepatitis C virus. The only other experimental animal that has been demonstrated to be sensitive to both of these viruses is the chimpanzee, but restrictions on animal testing have meant that experiments using chimpanzees have become almost impossible. Consequently, the development of the tupaia for use as an animal infection model could become a powerful tool for hepatitis virus research and in preclinical studies on drug development.

  4. Immunohistochemical detection of Tritrichomonas foetus in experimentally infected mice

    Directory of Open Access Journals (Sweden)

    Monteavaro Cristina Esther

    2000-01-01

    Full Text Available The need to intensify knowledge of the pathogenesis of bovine genital trichomoniasis (BGT led to the use of alternative animal models such as the mouse. Nevertheless, it is necessary to elucidate the dynamics of the infection in this animal species, evaluating different stages of the colonization and evolution of the pathological alterations. The immunohistochemistry (IHC offers advantages over the routine histopathological staining techniques for the detection of the protozoan in tissues, cellular detritus and inside the macrophages. The goal of the present study was to demonstrate the presence of Tritrichomonas foetus in the reproductive tract of infected mice using an IHC technique. Female BALB/c mice were infected with a suspension of T. foetus by intravaginal route, in the estrum phase, detected by exfoliative vaginal cytology. After 10 weeks, the animals were sacrificed; uterus and vagina were fixed and histologically processed. Some slides were stained with HE. The rest of the slides were processed for IHC. An immunoadsorbed polyclonal serum against T. foetus was used. The avidine-biotine technique (HistoMouse, Zymed[tm] was employed. The histopathological studies showed a dilation of the uterine glands, presence of macrophages in the lumen of the organ and inner part of the endometrial glands. No T. foetus was identified using this method. The IHQ allowed additionally the identification of the protozoan in the endometrium, endometrial glands, uterine lumen and inside neutrophils and macrophages. The cytological studies stained with IHC showed either isolated T. foetus adhered to epithelial cells or inside macrophages. This technique proves to be a useful tool for the study of the pathogenesis of bovine genital trichomoniasis (BGT in an experimental model.

  5. Experimental models of acute infection and Toll-like receptor driven septic shock.

    Science.gov (United States)

    Ferstl, Ruth; Spiller, Stephan; Fichte, Sylvia; Dreher, Stefan; Kirschning, Carsten J

    2009-01-01

    Mainly Gram-negative and Gram-positive bacterial infections, but also other infections such as with fungal or viral pathogens, can cause the life-threatening clinical condition of septic shock. Transgression of the host immune response from a local level limited to the pathogen's place of entry to the systemic level is recognised as a major mode of action leading to sepsis. This view has been established upon demonstration of the capacity of specific pathogen-associated molecular patterns (PAMPs) to elicit symptoms of septic shock upon systemic administration. Immune stimulatory PAMPs are agonists of soluble, cytoplasmic, as well as/or cell membrane-anchored and/or -spanning pattern recognition receptors (PRRs) such as Toll-like receptors (TLRs). However, reflection of pathogen-host crosstalk triggering sepsis pathogenesis upon an infection by a host response to challenge with an isolated PAMP is incomplete. Therefore, an experimental model more reflective of pathogen-host interaction requires experimental host confrontation with a specific pathogen in its viable form resulting in a collective stimulation of a variety of specific PRRs. This chapter describes methods to analyse innate pathogen sensing by the host on both a cellular and systemic level.

  6. Specific Depletion of Ly6Chi Inflammatory Monocytes Prevents Immunopathology in Experimental Cerebral Malaria

    Science.gov (United States)

    Kuepper, Janina M.; Biswas, Aindrila; Djie-Maletz, Andrea; Limmer, Andreas; van Rooijen, Nico; Mack, Matthias; Hoerauf, Achim; Dunay, Ildiko Rita

    2015-01-01

    Plasmodium berghei ANKA (PbA) infection of C57BL/6 mice leads to experimental cerebral malaria (ECM) that is commonly associated with serious T cell mediated damage. In other parasitic infection models, inflammatory monocytes have been shown to regulate Th1 responses but their role in ECM remains poorly defined, whereas neutrophils are reported to contribute to ECM immune pathology. Making use of the recent development of specific monoclonal antibodies (mAb), we depleted in vivo Ly6Chi inflammatory monocytes (by anti-CCR2), Ly6G+ neutrophils (by anti-Ly6G) or both cell types (by anti-Gr1) during infection with Ovalbumin-transgenic PbA parasites (PbTg). Notably, the application of anti-Gr1 or anti-CCR2 but not anti-Ly6G antibodies into PbTg-infected mice prevented ECM development. In addition, depletion of Ly6Chi inflammatory monocytes but not neutrophils led to decreased IFNγ levels and IFNγ+CD8+ T effector cells in the brain. Importantly, anti-CCR2 mAb injection did not prevent the generation of PbTg-specific T cell responses in the periphery, whereas anti-Gr1 mAb injection strongly diminished T cell frequencies and CTL responses. In conclusion, the specific depletion of Ly6Chi inflammatory monocytes attenuated brain inflammation and immune cell recruitment to the CNS, which prevented ECM following Plasmodium infection, pointing out a substantial role of Ly6C+ monocytes in ECM inflammatory processes. PMID:25884830

  7. Specific depletion of Ly6C(hi) inflammatory monocytes prevents immunopathology in experimental cerebral malaria.

    Science.gov (United States)

    Schumak, Beatrix; Klocke, Katrin; Kuepper, Janina M; Biswas, Aindrila; Djie-Maletz, Andrea; Limmer, Andreas; van Rooijen, Nico; Mack, Matthias; Hoerauf, Achim; Dunay, Ildiko Rita

    2015-01-01

    Plasmodium berghei ANKA (PbA) infection of C57BL/6 mice leads to experimental cerebral malaria (ECM) that is commonly associated with serious T cell mediated damage. In other parasitic infection models, inflammatory monocytes have been shown to regulate Th1 responses but their role in ECM remains poorly defined, whereas neutrophils are reported to contribute to ECM immune pathology. Making use of the recent development of specific monoclonal antibodies (mAb), we depleted in vivo Ly6C(hi) inflammatory monocytes (by anti-CCR2), Ly6G+ neutrophils (by anti-Ly6G) or both cell types (by anti-Gr1) during infection with Ovalbumin-transgenic PbA parasites (PbTg). Notably, the application of anti-Gr1 or anti-CCR2 but not anti-Ly6G antibodies into PbTg-infected mice prevented ECM development. In addition, depletion of Ly6C(hi) inflammatory monocytes but not neutrophils led to decreased IFNγ levels and IFNγ+CD8+ T effector cells in the brain. Importantly, anti-CCR2 mAb injection did not prevent the generation of PbTg-specific T cell responses in the periphery, whereas anti-Gr1 mAb injection strongly diminished T cell frequencies and CTL responses. In conclusion, the specific depletion of Ly6C(hi) inflammatory monocytes attenuated brain inflammation and immune cell recruitment to the CNS, which prevented ECM following Plasmodium infection, pointing out a substantial role of Ly6C+ monocytes in ECM inflammatory processes.

  8. Specific depletion of Ly6C(hi inflammatory monocytes prevents immunopathology in experimental cerebral malaria.

    Directory of Open Access Journals (Sweden)

    Beatrix Schumak

    Full Text Available Plasmodium berghei ANKA (PbA infection of C57BL/6 mice leads to experimental cerebral malaria (ECM that is commonly associated with serious T cell mediated damage. In other parasitic infection models, inflammatory monocytes have been shown to regulate Th1 responses but their role in ECM remains poorly defined, whereas neutrophils are reported to contribute to ECM immune pathology. Making use of the recent development of specific monoclonal antibodies (mAb, we depleted in vivo Ly6C(hi inflammatory monocytes (by anti-CCR2, Ly6G+ neutrophils (by anti-Ly6G or both cell types (by anti-Gr1 during infection with Ovalbumin-transgenic PbA parasites (PbTg. Notably, the application of anti-Gr1 or anti-CCR2 but not anti-Ly6G antibodies into PbTg-infected mice prevented ECM development. In addition, depletion of Ly6C(hi inflammatory monocytes but not neutrophils led to decreased IFNγ levels and IFNγ+CD8+ T effector cells in the brain. Importantly, anti-CCR2 mAb injection did not prevent the generation of PbTg-specific T cell responses in the periphery, whereas anti-Gr1 mAb injection strongly diminished T cell frequencies and CTL responses. In conclusion, the specific depletion of Ly6C(hi inflammatory monocytes attenuated brain inflammation and immune cell recruitment to the CNS, which prevented ECM following Plasmodium infection, pointing out a substantial role of Ly6C+ monocytes in ECM inflammatory processes.

  9. Cytokine, antibody and proliferative cellular responses elicited by Taenia solium calreticulin upon experimental infection in hamsters.

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    Fela Mendlovic

    Full Text Available Taenia solium causes two diseases in humans, cysticercosis and taeniosis. Tapeworm carriers are the main risk factor for neurocysticercosis. Limited information is available about the immune response elicited by the adult parasite, particularly the induction of Th2 responses, frequently associated to helminth infections. Calreticulin is a ubiquitous, multifunctional protein involved in cellular calcium homeostasis, which has been suggested to play a role in the regulation of immune responses. In this work, we assessed the effect of recombinant T. solium calreticulin (rTsCRT on the cytokine, humoral and cellular responses upon experimental infection in Syrian Golden hamsters (Mesocricetus auratus. Animals were infected with T. solium cysticerci and euthanized at different times after infection. Specific serum antibodies, proliferative responses in mesenteric lymph nodes and spleen cells, as well as cytokines messenger RNA (mRNA were analyzed. The results showed that one third of the infected animals elicited anti-rTsCRT IgG antibodies. Interestingly, mesenteric lymph node (MLN cells from either infected or non-infected animals did not proliferate upon in vitro stimulation with rTsCRT. Additionally, stimulation with a tapeworm crude extract resulted in increased expression of IL-4 and IL-5 mRNA. Upon stimulation, rTsCRT increased the expression levels of IL-10 in spleen and MLN cells from uninfected and infected hamsters. The results showed that rTsCRT favors a Th2-biased immune response characterized by the induction of IL-10 in mucosal and systemic lymphoid organs. Here we provide the first data on the cytokine, antibody and cellular responses to rTsCRT upon in vitro stimulation during taeniasis.

  10. Carbohydrate-rich high-molecular-mass antigens are strongly recognized during experimental Histoplasma capsulatum infection

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    Fabrine Sales Massafera Tristão

    2012-04-01

    Full Text Available INTRODUCTION: During histoplasmosis, Histoplasma capsulatum soluble antigens (CFAg can be naturally released by yeast cells. Because CFAg can be specifically targeted during infection, in the present study we investigated CFAg release in experimental murine histoplasmosis, and evaluated the host humoral immune response against high-molecular-mass antigens (hMMAg. >150 kDa, the more immunogenic CFAg fraction. METHODS: Mice were infected with 2.2x10(4 H. capsulatum IMT/HC128 yeast cells. The soluble CFAg, IgG anti-CFAg, IgG anti-hMMAg, and IgG-hMMAg circulating immune complexes (CIC levels were determined by enzymelinked immunosorbent assay, at days 0, 7, 14, and 28 post-infection. RESULTS: We observed a progressive increase in circulating levels of CFAg, IgG anti-CFAg, IgG anti-hMMAg, and IgG-hMMAg CIC after H. capsulatum infection. The hMMAg showed a high percentage of carbohydrates and at least two main immunogenic components. CONCLUSIONS: We verified for the first time that hMMAg from H. capsulatum IMT/HC128 strain induce humoral immune response and lead to CIC formation during experimental histoplasmosis.

  11. Experimental feline enteric coronavirus infection reveals an aberrant infection pattern and shedding of mutants with impaired infectivity in enterocyte cultures

    Science.gov (United States)

    Desmarets, Lowiese M. B.; Vermeulen, Ben L.; Theuns, Sebastiaan; Conceição-Neto, Nádia; Zeller, Mark; Roukaerts, Inge D. M.; Acar, Delphine D.; Olyslaegers, Dominique A. J.; Van Ranst, Marc; Matthijnssens, Jelle; Nauwynck, Hans J.

    2016-01-01

    Feline infectious peritonitis (FIP) results from mutations in the viral genome during a common feline enteric coronavirus (FECV) infection. Since many virological and immunological data on FECV infections are lacking, the present study investigated these missing links during experimental infection of three SPF cats with FECV strain UCD. Two cats showed mild clinical signs, faecal shedding of infectious virus from 4 dpi, a cell-associated viraemia at inconsistent time points from 5 dpi, a highly neutralising antibody response from 9 dpi, and no major abnormalities in leukocyte numbers. Faecal shedding lasted for 28–56 days, but virus shed during this stage was less infectious in enterocyte cultures and affected by mutations. Remarkably, in the other cat neither clinical signs nor acute shedding were seen, but virus was detected in blood cells from 3 dpi, and shedding of non-enterotropic, mutated viruses suddenly occurred from 14 dpi onwards. Neutralising antibodies arose from 21 dpi. Leukocyte numbers were not different compared to the other cats, except for the CD8+ regulatory T cells. These data indicate that FECV can infect immune cells even in the absence of intestinal replication and raise the hypothesis that the gradual adaptation to these cells can allow non-enterotropic mutants to arise. PMID:26822958

  12. Toxoplasma gondii: infection natural congenital in cattle and an experimental inoculation of gestating cows with oocysts.

    Science.gov (United States)

    Costa, Gustavo Henrique Nogueira; da Costa, Alvimar José; Lopes, Welber Daniel Zanetti; Bresciani, Katia Denise Saraiva; dos Santos, Thais Rabelo; Esper, César Roberto; Santana, Aureo Evangelista

    2011-01-01

    Two studies, of a natural infection and an experimental infection, were performed in order to study congenital transmission of Toxoplasma gondii in cattle. In the first study, 50 fetuses were harvested from gestating cows that were eutanasied at a municipal slaughterhouse in Jaboticabal, São Paulo state, Brazil. In the second study, 11 gestating cows were divided into four groups for inoculation with T. gondii: GI consisted of three cows inoculated with 1.0 × 10(5) oocysts during their first trimester of gestation; GII consisted of three cows inoculated with 1.0 × 10(5) oocysts during their second trimester of gestation; GIII consisted of three cows inoculated with 1.0 × 10(5) oocysts during their last trimester of gestation; and GIV consisted of two control cows, one during its first and the other during its second trimester of gestation. In both studies, the presence of T. gondii was confirmed both indirectly by immunofluorescence assay (IFAT). In the natural infection experiment, 18% (9/50) of the gestating cows were confirmed to have specific antibodies (IFAT--1:64) against T. gondii. The bioassay was able to diagnose the presence of T. gondii in the tissue samples from three calves. In the second experiment, the nine cows from groups I, II and III presented with specific antibodies (IFAT) against T. gondii. In contrast, T. gondii could not be detected by IFAT, histopathological examination or the bioassay in any of the nine calves born to cows experimentally infected with T. gondii oocysts. Based on the results from both studies, we conclude that congenital infection of T. gondii in cattle, while infrequent, does occur naturally. The pathogenicity of the strain of T. gondii may influence the likelihood of this route of transmission. Copyright © 2010 Elsevier Inc. All rights reserved.

  13. Aspects of resistance to experimental infection with Trypanosoma cruzi

    International Nuclear Information System (INIS)

    Dias, Viviane Liotti

    2010-01-01

    Chagas disease, a zoonosis caused by the protozoan Trypanosoma cruzi, has a wide distribution in Latin America and extends from the southern part of the United States to Argentina. A number of 10 million of infected people is estimated and another 25 million exposed to the risk. Although discovered over a century, Chagas disease is still a serious infection that causes great socioeconomic impact, with no effective treatment at the chronic phase and in which, a lack of scientific knowledge can be observed. The main goal of this work was that obtaining and using consomic strain of mice, the resistance could be investigated. Consomic strains were produced by programmed mating, in which the animals were monitored with DNA polymorphic markers, and one of his chromosomes was replaced by his homologue from another strain. As parental, were used, the inbred strains C57BL/6/J Unib with resistant phenotype (donor) and as receiver, the A/JUnib strain, that has a susceptible phenotype. These models were used to produce five consomic strains: for the chromosomes 7 (CSs7), 11 (CSs11), 14 (CSs14), 17 (CSs17) and 19 (CSs19), described by Passos et al. (2003) as important in controlling infection caused by the Y strain of T. cruzi. In experimental testing, the consomics were inoculated intraperitoneally at doses of 10 1 , 10 2 , 10 3 and 10 4 using as control, animals from both parental lines. In all consomics, resistance was higher than that observed in the susceptible parental. In a second protocol, the consomics were mated with scheduled associations and the progenies were challenged with inocula employing increasing doses of trypomastigotes. The resistance observed in this group was also higher than that observed in the parental with susceptible phenotype. The observed results demonstrate that the use of the consomic strains that were produced order to assess the contribution of each chromosome in the resistance, as well as the effects of association between chromosomes are an

  14. Antibody dynamics in BRSV-infected Danish dairy herds as determined by isotype-specific immunoglobulins

    DEFF Research Database (Denmark)

    Uttenthal, Åse; Larsen, Lars Erik; Philipsen, J.S.

    2000-01-01

    Using specific ELISAs, antibody levels of four different isotypes to bovine respiratory syncytial virus (BRSV) were determined in calves, following experimental BRSV infection. Most calves experienced an increase in the specific IgM and IgG1 titres about 6-10 days after infection with BRSV. The Ig......M titre was transient showing positive titres for only 5-10 days, while specific IgG1 was present for a longer time. IgA was detected concomitantly with IgM but at a lower level. Production of IgG2 anti-BRSV antibodies was detected from 3 weeks after infection. In two closed herds, repeated blood......, another herd with acute BRSV was followed by weekly blood samples in six calves; in both herds IgM and IgG1 was detected shortly after the appearance of clinical signs. Serum samples from 50 Danish dairy herds (453 samples) were tested for immunoglobulins of the isotypes IgG1, IgG2 and IgM. The presence...

  15. Infectivity and temperature tolerance of non-encapsulating Trichinella zimbabwensis in experimentally infected red foxes (Vulpes vulpes)

    DEFF Research Database (Denmark)

    Hurníková, Z.; Dubinský, P.; Mukaratirwa, S.

    2004-01-01

    The non-encapsulating Trichinella zimbabwensis was evaluated for infectivity in red foxes (Vulpes vulpes), the larval distribution and cold tolerance in fox muscle tissue. Six red foxes were experimentally infected with T. zimbabwensis larvae. Five weeks after inoculation, muscle larvae were...... recovered from 9 different muscle types using artificial digestion method. The establishment of infection in all infected red foxes demonstrated the ability of T. zimbabwensis to complete its life cycle in a carnivore mammal host. The larvae recovered from fox muscle tissue were infective to mice, they have...

  16. Humoral immunity through immunoglobulin M protects mice from an experimental actinomycetoma infection by Nocardia brasiliensis.

    Science.gov (United States)

    Salinas-Carmona, Mario C; Pérez-Rivera, Isabel

    2004-10-01

    An experimental model of infection with Nocardia brasiliensis, used as an example of a facultative intracellular pathogen, was tested. N. brasiliensis was injected into the rear foot pads of BALB/c mice to establish an infection. Within 30 days, infected animals developed a chronic actinomycetoma infection. Batch cultures of N. brasiliensis were used to purify P61, P38, and P24 antigens; P61 is a catalase, and P38 is a protease with strong caseinolytic activity. Active and passive immunizations of BALB/c mice with these three purified soluble antigens were studied. Protection was demonstrated for actively immunized mice. However, immunity lasted only 30 days. Other groups of immunized mice were bled at different times, and their sera were passively transferred to naive recipients that were then infected with N. brasiliensis. Sera collected 5, 6, and 7 days after donor immunization conferred complete, long-lasting protection. The protective effect of passive immunity decreased when sera were collected 2 weeks after donor immunization. However, neither the early sera (1-, 2-, and 3-day sera) nor the later sera (30- or 45-day sera) prevented the infection. Hyperimmune sera with the highest levels of immunoglobulin G (IgG) to N. brasiliensis antigens did not protect at all. The antigens tested induced two IgM peaks. The first peak was present 3 days after immunization but was not antigen specific and did not transfer protection. The second peak was evident 7 days after immunization, was an IgM response, was antigen specific, and conferred protection. This results clearly demonstrate that IgM antibodies protect the host against a facultative intracellular bacterium.

  17. Plasma thromboxane B2 levels in horses experimentally infected with Strongylus vulgaris.

    Science.gov (United States)

    Cambridge, H; Reynoldson, J A; Dunsmore, J D

    1989-06-01

    Plasma thromboxane B2 (TXB2) the stable inactive metabolite of thromboxane A2 (TXA2), was measured daily by specific radioimmunoassay in three groups of animals before and after experimental infection with Strongylus vulgaris. Infection of four 'parasite naive' foals produced a typical acute syndrome with intermittent but statistically insignificant rises in TXB2 levels. Interpretation of results was complicated by the presence of a non-septic peritonitis associated with implantation of the foals with electrodes for recording myoelectrical activity. In two foals of similar age, with some natural exposure to S. vulgaris, there was little or no clinical response to infection and increases in TXB2 were absent. Baseline levels were also much lower, indicating that the peritonitis may have affected the results obtained in the first group of foals. Severe mesenteric arteritis was confirmed at necropsy in all six foals. A third group of yearling horses, all with natural exposure to the parasite, were generally resistant to infection. One animal developed arteritis with clinical signs of diarrhoea and mild colic, and also showed intermittent increases in TXB2. The mean plasma TXB2 level after infection was significantly higher than in the control period, although absolute levels were lower than those recorded in the 'parasite naive' foals. Other animals in this group had low TXB2 levels and minimal arteritis was found at necropsy. These results indicate that although infection appears to have an effect on plasma TXB2, the changes are inconsistent and not reliable indicators of the presence of verminous arteritis. The results also confirm the difficulty in establishing infection and the variability of the response in animals with previous exposure.

  18. Cross-Species Infectivity of H3N8 Influenza Virus in an Experimental Infection in Swine.

    Science.gov (United States)

    Solórzano, Alicia; Foni, Emanuela; Córdoba, Lorena; Baratelli, Massimiliano; Razzuoli, Elisabetta; Bilato, Dania; Martín del Burgo, María Ángeles; Perlin, David S; Martínez, Jorge; Martínez-Orellana, Pamela; Fraile, Lorenzo; Chiapponi, Chiara; Amadori, Massimo; del Real, Gustavo; Montoya, María

    2015-11-01

    Avian influenza A viruses have gained increasing attention due to their ability to cross the species barrier and cause severe disease in humans and other mammal species as pigs. H3 and particularly H3N8 viruses, are highly adaptive since they are found in multiple avian and mammal hosts. H3N8 viruses have not been isolated yet from humans; however, a recent report showed that equine influenza A viruses (IAVs) can be isolated from pigs, although an established infection has not been observed thus far in this host. To gain insight into the possibility of H3N8 avian IAVs to cross the species barrier into pigs, in vitro experiments and an experimental infection in pigs with four H3N8 viruses from different origins (equine, canine, avian, and seal) were performed. As a positive control, an H3N2 swine influenza virus A was used. Although equine and canine viruses hardly replicated in the respiratory systems of pigs, avian and seal viruses replicated substantially and caused detectable lesions in inoculated pigs without previous adaptation. Interestingly, antibodies against hemagglutinin could not be detected after infection by hemagglutination inhibition (HAI) test with avian and seal viruses. This phenomenon was observed not only in pigs but also in mice immunized with the same virus strains. Our data indicated that H3N8 IAVs from wild aquatic birds have the potential to cross the species barrier and establish successful infections in pigs that might spread unnoticed using the HAI test as diagnostic tool. Although natural infection of humans with an avian H3N8 influenza A virus has not yet been reported, this influenza A virus subtype has already crossed the species barrier. Therefore, we have examined the potential of H3N8 from canine, equine, avian, and seal origin to productively infect pigs. Our results demonstrated that avian and seal viruses replicated substantially and caused detectable lesions in inoculated pigs without previous adaptation. Surprisingly, we

  19. Effect of Experimental Coccidiosis Infections on Body Weight Gain ...

    African Journals Online (AJOL)

    Infections with E. tenella in broiler breeder males showed that body weight gains of the uninfected males were significantly greater (p< 0.05) at 5, 7 and 14 days post inoculation (dpi) than those of the infected groups. Sperm productions at 0, 5 and 7 dpi (0=day of inoculation with infected oocysts) for the uninfected controls ...

  20. Specifics of phytomass combustion in small experimental device

    Science.gov (United States)

    Lenhard, Richard; Mičieta, Jozef; Jandačka, Jozef; Gavlas, Stanislav

    2015-05-01

    A wood pellet combustion carries out with high efficiency and comfort in modern pellet boilers. These facts help to increase the amount of installed pellet boilers in households. The combustion process quality depends besides the combustion conditions also on the fuel quality. The wood pellets, which don`t contain the bark and branches represent the highest quality. Because of growing pellet demand, an herbal biomass (phytomass), which is usually an agricultural by-product becomes economically attractive for pellet production. Although the phytomass has the net calorific value relatively slightly lower than the wood biomass, it is often significantly worse in view of the combustion process and an emission production. The combustion of phytomass pellets causes various difficulties in small heat sources, mainly due to a sintering of fuel residues. We want to avoid the ash sintering by a lowering of temperature in the combustion chamber below the ash sintering temperature of phytomass via the modification of a burner design. For research of the phytomass combustion process in the small boilers is constructed the experimental combustion device. There will investigate the impact of cooling intensity of the combustion chamber on the combustion process and emissions. Arising specific requirements from the measurement will be the basis for the design of the pellet burner and for the setting of operating parameters to the trouble-free phytomass combustion was guaranteed.

  1. Specifics of phytomass combustion in small experimental device

    Directory of Open Access Journals (Sweden)

    Lenhard Richard

    2015-01-01

    Full Text Available A wood pellet combustion carries out with high efficiency and comfort in modern pellet boilers. These facts help to increase the amount of installed pellet boilers in households. The combustion process quality depends besides the combustion conditions also on the fuel quality. The wood pellets, which don`t contain the bark and branches represent the highest quality. Because of growing pellet demand, an herbal biomass (phytomass, which is usually an agricultural by-product becomes economically attractive for pellet production. Although the phytomass has the net calorific value relatively slightly lower than the wood biomass, it is often significantly worse in view of the combustion process and an emission production. The combustion of phytomass pellets causes various difficulties in small heat sources, mainly due to a sintering of fuel residues. We want to avoid the ash sintering by a lowering of temperature in the combustion chamber below the ash sintering temperature of phytomass via the modification of a burner design. For research of the phytomass combustion process in the small boilers is constructed the experimental combustion device. There will investigate the impact of cooling intensity of the combustion chamber on the combustion process and emissions. Arising specific requirements from the measurement will be the basis for the design of the pellet burner and for the setting of operating parameters to the trouble-free phytomass combustion was guaranteed.

  2. Trypanosoma cruzi infection in the opossum Didelphis marsupialis: absence of neonatal transmission and protection by maternal antibodies in experimental infections

    Directory of Open Access Journals (Sweden)

    Ana M. Jansen

    1994-03-01

    Full Text Available The high rate of natural Trypanosoma cruzi infection found in opossums does not always correlate with appreciable densities of local triatomid populations. One alternative method which might bypass the invertebrate vector is direct transmission from mother to offspring. This possibility was investigated in five T. cruzi infected females and their litters (24 young. The influence of maternal antibodies transferred via lactation, on the course of experimental infection, was also examined. Our results show that neonatal transmission is probably not responsible for the high rate of natural T. cruzi infection among opossums. In addition antibodies of maternal origin confer a partial protection to the young. This was demonstrated by the finding of a double prepatency period and 4,5 fold lower levels of circulating parasites, in experimentally infected pouch young from infected as compared to control uninfected mothes. On the other hand, the duration of patent parasitemia was twice as long as that observed in the control group.

  3. Experimental cross-species infection of common marmosets by titi monkey adenovirus.

    Directory of Open Access Journals (Sweden)

    Guixia Yu

    Full Text Available Adenoviruses are DNA viruses that infect a number of vertebrate hosts and are associated with both sporadic and epidemic disease in humans. We previously identified a novel adenovirus, titi monkey adenovirus (TMAdV, as the cause of a fulminant pneumonia outbreak in a colony of titi monkeys (Callicebus cupreus at a national primate center in 2009. Serological evidence of infection by TMAdV was also found in a human researcher at the facility and household family member, raising concerns for potential cross-species transmission of the virus. Here we present experimental evidence of cross-species TMAdV infection in common marmosets (Callithrix jacchus. Nasal inoculation of a cell cultured-adapted TMAdV strain into three marmosets produced an acute, mild respiratory illness characterized by low-grade fever, reduced activity, anorexia, and sneezing. An increase in virus-specific neutralization antibody titers accompanied the development of clinical signs. Although serially collected nasal swabs were positive for TMAdV for at least 8 days, all 3 infected marmosets spontaneously recovered by day 12 post-inoculation, and persistence of the virus in tissues could not be established. Thus, the pathogenesis of experimental inoculation of TMAdV in common marmosets resembled the mild, self-limiting respiratory infection typically seen in immunocompetent human hosts rather than the rapidly progressive, fatal pneumonia observed in 19 of 23 titi monkeys during the prior 2009 outbreak. These findings further establish the potential for adenovirus cross-species transmission and provide the basis for development of a monkey model useful for assessing the zoonotic potential of adenoviruses.

  4. Immune responsiveness associated with experimental Encephalitozoon intestinalis infection in immunocompetent rats

    Directory of Open Access Journals (Sweden)

    Omalu ICJ

    2007-01-01

    Full Text Available Purpose: Microsporidial infections have been recognized as an increasingly important infection in immuncompromised patients, particularly those infected with HIV/AIDS. This study was designed to study immune responses associated with experimental Encephalitozoon intestinalis infection in immunocompetent rats. Materials and Methods: Thirty-four Rats in 3 groups, A (Control, B (Intraperitoneal and C (Oral were given injections of 0.5 ml of 2 x 10 6 of purified spores of Encephalitotozoon intestinalis spores and were observed for serum specific IgG for 21 days using both direct and indirect ELISA. Results: In indirect ELISA, specific lgG were detected on days 7, 14 and 21 for the group B rats and on day 21 for group C and in direct ELISA method, specific lgG were detected in-group B rats on days 7 and 21, for group C rats on day 21 only, while in the control rats, specific lgG were not detected. There was no significant difference between the direct and indirect methods (df=1, X 2 , P>0.05. E. intestinalis was observed in stool samples of rats in 1/12 (08.33% on days 14 and 21 in group B, and in 4/10 (33.33%, 3/10 (25.00% and 2/10 (16.67% on days 7, 14 and 21 respectively in group C. In group A, which is the control rats, no microsporidia were observed on days 0, 7, 14 and 21. Conclusions: There were no changes in the T-lymphocyte counts of rats prior to and after inoculation with spores. Extensive lesions were observed along the intestinal walls especially on the middle and lower sections of group C rats only.

  5. Experimental infection in Cavia porcellus by infected Amblyomma ovale nymphs with Rickettsia sp. (Atlantic rainforest strain).

    Science.gov (United States)

    Brustolin, Joice Magali; da Silva Krawczak, Felipe; Alves, Marta Elena Machado; Weiller, Maria Amélia; de Souza, Camila Lopes; Rosa, Fábio Brum; Cadore, Gustavo Cauduro; Dos Anjos Lopes, Sônia Terezinha; Labruna, Marcelo Bahia; Vogel, Fernanda Silveira Flores; de Avila Botton, Sônia; Sangioni, Luís Antônio

    2018-03-01

    This study describes experimental infection of guinea pigs (Cavia porcellus) infested with naturally infected Amblyomma ovale nymphs with Rickettsia sp. (Atlantic rainforest strain), and the capacity of A. ovale nymphs to transmit this bacterium. Twenty-six guinea pigs were divided into the following groups: G1, 10 animals infested with uninfected A. ovale nymphs; G2, 10 animals infested with nymphs infected with Rickettsia sp. (Atlantic rainforest strain); and G3, 6 animals without tick infestation. Blood samples were taken 7, 14, 21, and 28 days post-infestation for serological and hematological tests. For histopathological analysis and rickettsial DNA detection, fragments of the spleen, lung, brain, and liver were harvested after euthanasia. The average feeding period for nymphs was 6.6 days for G1 and 6 days for G2. Hemolymph and PCR assays, performed to detect the causative agent in ticks, indicated that in G1, all ticks were negative, and in G2, all nymphs were positive by PCR and 80% (8/10) was positive by hemolymph tests. The only clinical change was skin scarring at the tick attachment site. Hematological parameters indicated leukopenia and total plasma protein (TPP) increased with decreased platelets in G1. In G2, leukocytosis, neutrophilia, monocytosis, an increase in platelets, and reduced TPP were observed. Only G2 guinea pigs were seroconverted (80%; 8/10). Histopathology tests indicated mild, diffuse hemosiderosis and mild, multifocal, follicular hyperplasia in the spleen. Molecular analysis did not detect Rickettsia sp. DNA in C. porcellus tissues. We demonstrated the capacity of A. ovale nymphs to transmit Rickettsia sp. (Atlantic rainforest strain) to guinea pigs.

  6. Studies on the Leucocytic Response to Experimental Infection with ...

    African Journals Online (AJOL)

    Also, neutrophil numbers declined significantly (P < 0.05) in red fronted gazelles infected either singly with Trypanosoma brucei or concurrently with both parasites while those infected singly with Haemonchus contortus experienced a significant (P <0.05) rise in neutrophil counts which became evident from day 30 post ...

  7. Experimental Mycoplasma gallisepticum infections in captive-reared wild turkeys

    Science.gov (United States)

    Rocke, Tonie E.; Yuill, Thomas M.; Amundson, Terry E.

    1988-01-01

    The effects of Mycoplasma gallisepticum (MG) infections on egg production, fertility, and hatchability were studied in captive-reared wild turkeys (Meleagris gallopavo). Three groups of adult birds, each consisting of four hens and two toms, were exposed to MG by the respiratory route at the beginning of their breeding season. Fourteen control birds received sterile growth medium. Although no mortality of infected or control birds occurred, egg production during the first breeding season after infection was reduced. The mean number of eggs/hen/day produced by infected groups the first breeding season postexposure (PE) was significantly lower than the control value. The mean number of eggs produced daily by the same hens 1 yr later was unaffected by MG infection. The pecentage of fertile eggs produced by infected groups was slightly reduced in both the first and second breeding seasons PE. Hatchability of fertile eggs from infected hens was significantly lower than eggs from control hens. Productivity may be impaired if MG infections occur in free-ranging wild turkey populations.

  8. Virus specific antigens in mammalian cells infected with herpes simplex virus

    Science.gov (United States)

    Watson, D. H.; Shedden, W. I. H.; Elliot, A.; Tetsuka, T.; Wildy, P.; Bourgaux-Ramoisy, D.; Gold, E.

    1966-01-01

    Antisera to specific proteins in herpes simplex infected cells were produced by immunization of rabbits with infected rabbit kidney cells. These antisera were highly virus specific and produced up to twelve lines in immunodiffusion tests against infected cell extracts. Acrylamide electrophoresis and immunoelectrophoresis revealed up to ten virus specific proteins of varying size. ImagesFIG. 1FIG. 2FIG. 3FIG. 4FIG. 5 PMID:4288648

  9. Validation of a serum neutralization test for detection of antibodies specific to cyprinid herpesvirus 3 in infected common and koi carp (Cyprinus carpio)

    DEFF Research Database (Denmark)

    Cabon, J.; Louboutin, L.; Castric, J.

    2017-01-01

    healthy and naturally or experimentally CyHV-3-infected carp. French CyHV-3 isolate 07/108b was neutralized efficiently by sera from carp infected with European, American and Taiwanese CyHV-3 isolates, but no neutralization was observed using sera specific to other aquatic herpesviruses. Diagnostic...

  10. Preferential infection and depletion of Mycobacterium tuberculosis-specific CD4 T cells after HIV-1 infection

    NARCIS (Netherlands)

    Geldmacher, Christof; Ngwenyama, Njabulo; Schuetz, Alexandra; Petrovas, Constantinos; Reither, Klaus; Heeregrave, Edwin J.; Casazza, Joseph P.; Ambrozak, David R.; Louder, Mark; Ampofo, William; Pollakis, Georgios; Hill, Brenna; Sanga, Erica; Saathoff, Elmar; Maboko, Leonard; Roederer, Mario; Paxton, William A.; Hoelscher, Michael; Koup, Richard A.

    2010-01-01

    HIV-1 infection results in the progressive loss of CD4 T cells. In this study, we address how different pathogen-specific CD4 T cells are affected by HIV infection and the cellular parameters involved. We found striking differences in the depletion rates between CD4 T cells to two common

  11. DNA immunization against experimental genital herpes simplex virus infection.

    Science.gov (United States)

    Bourne, N; Stanberry, L R; Bernstein, D I; Lew, D

    1996-04-01

    A nucleic acid vaccine, expressing the gene encoding herpes simplex virus (HSV) type 2 glycoprotein D (gD2) under control of the cytomegalovirus immediate-early gene promoter, was used to immunize guinea pigs against genital HSV-2 infection. The vaccine elicited humoral immune responses comparable to those seen after HSV-2 infection. Immunized animals exhibited protection from primary genital HSV-2 disease with little or no development of vesicular skin lesions and significantly reduced HSV-2 replication in the genital tract. After recovery from primary infection, immunized guinea pigs experienced significantly fewer recurrences and had significantly less HSV-2 genomic DNA detected in the sacral dorsal root ganglia compared with control animals. Thus, immunization reduced the burden of latent infection resulting from intravaginal HSV-2 challenge, and a nucleic acid vaccine expressing the HSV-2 gD2 antigen protected guinea pigs against genital herpes, limiting primary infection and reducing the magnitude of latent infection and the frequency of recurrent disease.

  12. Host-pathogen interactions in specific pathogen-free chickens following aerogenous infection with Chlamydia psittaci and Chlamydia abortus.

    Science.gov (United States)

    Kalmar, Isabelle; Berndt, Angela; Yin, Lizi; Chiers, Koen; Sachse, Konrad; Vanrompay, Daisy

    2015-03-15

    Although Chlamydia (C.) psittaci infections are recognized as an important factor causing economic losses and impairing animal welfare in poultry production, the specific mechanisms leading to severe clinical outcomes are poorly understood. In the present study, we comparatively investigated pathology and host immune response, as well as systemic dissemination and expression of essential chlamydial genes in the course of experimental aerogeneous infection with C. psittaci and the closely related C. abortus, respectively, in specific pathogen-free chicks. Clinical signs appeared sooner and were more severe in the C. psittaci-infected group. Compared to C. abortus infection, more intense systemic dissemination of C. psittaci correlated with higher and faster infiltration of immune cells, as well as more macroscopic lesions and epithelial pathology, such as hyperplasia and erosion. In thoracic air sac tissue, mRNA expression of immunologically relevant factors, such as IFN-γ, IL-1β, IL-6, IL-17, IL-22, LITAF and iNOS was significantly stronger up-regulated in C. psittaci- than in C. abortus-infected birds between 3 and 14 days post-infection. Likewise, transcription rates of the chlamydial genes groEL, cpaf and ftsW were consistently higher in C. psittaci during the acute phase. These findings illustrate that the stronger replication of C. psittaci in its natural host also evoked a more intense immune response than in the case of C. abortus infection. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Experimental Model of Tuberculosis in the Domestic Goat after Endobronchial Infection with Mycobacterium caprae ▿

    Science.gov (United States)

    Pérez de Val, Bernat; López-Soria, Sergio; Nofrarías, Miquel; Martín, Maite; Vordermeier, H. Martin; Villarreal-Ramos, Bernardo; Romera, Nadine; Escobar, Manel; Solanes, David; Cardona, Pere-Joan; Domingo, Mariano

    2011-01-01

    Caprine tuberculosis (TB) has increased in recent years, highlighting the need to address the problem the infection poses in goats. Moreover, goats may represent a cheaper alternative for testing of prototype vaccines in large ruminants and humans. With this aim, a Mycobacterium caprae infection model has been developed in goats. Eleven 6-month-old goats were infected by the endobronchial route with 1.5 × 103 CFU, and two other goats were kept as noninfected controls. The animals were monitored for clinical and immunological parameters throughout the experiment. After 14 weeks, the goats were euthanized, and detailed postmortem analysis of lung lesions was performed by multidetector computed tomography (MDCT) and direct observation. The respiratory lymph nodes were also evaluated and cultured for bacteriological analysis. All infected animals were positive in a single intradermal comparative cervical tuberculin (SICCT) test at 12 weeks postinfection (p.i.). Gamma interferon (IFN-γ) antigen-specific responses were detected from 4 weeks p.i. until the end of the experiment. The humoral response to MPB83 was especially strong at 14 weeks p.i. (13 days after SICCT boost). All infected animals presented severe TB lesions in the lungs and associated lymph nodes. M. caprae was recovered from pulmonary lymph nodes in all inoculated goats. MDCT allowed a precise quantitative measure of TB lesions. Lesions in goats induced by M. caprae appeared to be more severe than those induced in cattle by M. bovis over a similar period of time. The present work proposes a reliable new experimental animal model for a better understanding of caprine tuberculosis and future development of vaccine trials in this and other species. PMID:21880849

  14. Specificity and polyreactivity of the antibody response during natural HIV-1 infection

    OpenAIRE

    Wang, Xin

    2006-01-01

    The specificity and polyreactivity of the antibody response in natural HIV-1 infection were studied. First, to investigate the overall antibody response, overlapping linear peptides were used to screen sera taken from HIV-1-infected individuals. The polyclonal antibody response was relatively stable during long-term infection, compared with acute infection, and mostly directed against immunodominant regions. Low level, transient antibody responses were detected against membrane proximal exter...

  15. Experimental analysis of specification language impact on NPP software diversity

    International Nuclear Information System (INIS)

    Yoo, Chang Sik; Seong, Poong Hyun

    1998-01-01

    When redundancy and diversity is applied in NPP digital computer system, diversification of system software may be a critical point for the entire system dependability. As the means of enhancing software diversity, specification language diversity is suggested in this study. We set up a simple hypothesis for the specification language impact on common errors, and an experiment based on NPP protection system application was performed. Experiment result showed that this hypothesis could be justified and specification language diversity is effective in overcoming software common mode failure problem

  16. Lassa virus infection in experimentally infected marmosets: liver pathology and immunophenotypic alterations in target tissues.

    Science.gov (United States)

    Carrion, Ricardo; Brasky, Kathleen; Mansfield, Keith; Johnson, Curtis; Gonzales, Monica; Ticer, Anysha; Lukashevich, Igor; Tardif, Suzette; Patterson, Jean

    2007-06-01

    Lassa virus causes thousands of deaths annually in western Africa and is considered a potential biological weapon. In an attempt to develop a small nonhuman primate model of Lassa fever, common marmosets were subcutaneously inoculated with Lassa virus strain Josiah. This inoculation resulted in a systemic disease with clinical and morphological features mirroring those in fatal human Lassa infection: fever, weight loss, high viremia and viral RNA load in tissues, elevated liver enzymes, and severe morbidity between days 15 and 20. The most prominent histopathology findings included multifocal hepatic necrosis with mild inflammation and hepatocyte proliferation, lymphoid depletion, and interstitial nephritis. Cellular aggregates in regions of hepatocellular necrosis were largely composed of HAM56-positive macrophages, devoid of CD3-positive and CD20-positive cells, and characterized by marked reductions in the intensity of HLA-DP, DQ, DR staining. A marked reduction in the major histocompatibility complex class II expression was also observed in the lymph nodes. Immunophenotypic alterations in spleen included reductions in overall numbers of CD20-positive and CD3-positive cells and the disruption of lymphoid follicular architecture. These findings identify the common marmoset as an appropriate model of human Lassa fever and present the first experimental evidence that replication of Lassa virus in tissues is associated with alterations that would be expected to impair adaptive immunity.

  17. Vaccine-mediated immune responses to experimental pulmonary Cryptococcus gattii infection in mice.

    Directory of Open Access Journals (Sweden)

    Ashok K Chaturvedi

    Full Text Available Cryptococcus gattii is a fungal pathogen that can cause life-threatening respiratory and disseminated infections in immune-competent and immune-suppressed individuals. Currently, there are no standardized vaccines against cryptococcosis in humans, underlying an urgent need for effective therapies and/or vaccines. In this study, we evaluated the efficacy of intranasal immunization with C. gattii cell wall associated (CW and/or cytoplasmic (CP protein preparations to induce protection against experimental pulmonary C. gattii infection in mice. BALB/c mice immunized with C. gattii CW and/or CP protein preparations exhibited a significant reduction in pulmonary fungal burden and prolonged survival following pulmonary challenge with C. gattii. Protection was associated with significantly increased pro-inflammatory and Th1-type cytokine recall responses, in vitro and increased C. gattii-specific antibody production in immunized mice challenged with C. gattii. A number of immunodominant proteins were identified following immunoblot analysis of C. gattii CW and CP protein preparations using sera from immunized mice. Immunization with a combined CW and CP protein preparation resulted in an early increase in pulmonary T cell infiltrates following challenge with C. gattii. Overall, our studies show that C. gattii CW and CP protein preparations contain antigens that may be included in a subunit vaccine to induce prolonged protection against pulmonary C. gattii infection.

  18. Avian influenza in shorebirds: experimental infection of ruddy turnstones (Arenaria interpres) with avian influenza virus

    Science.gov (United States)

    Hall, Jeffrey S.; Krauss, Scott; Franson, J. Christian; TeSlaa, Joshua L.; Nashold, Sean W.; Stallknecht, David E.; Webby, Richard J.; Webster, Robert G.

    2013-01-01

    Background: Low pathogenic avian influenza viruses (LPAIV) have been reported in shorebirds, especially at Delaware Bay, USA, during spring migration. However, data on patterns of virus excretion, minimal infectious doses, and clinical outcome are lacking. The ruddy turnstone (Arenaria interpres) is the shorebird species with the highest prevalence of influenza virus at Delaware Bay. Objectives: The primary objective of this study was to experimentally assess the patterns of influenza virus excretion, minimal infectious doses, and clinical outcome in ruddy turnstones. Methods: We experimentally challenged ruddy turnstones using a common LPAIV shorebird isolate, an LPAIV waterfowl isolate, or a highly pathogenic H5N1 avian influenza virus. Cloacal and oral swabs and sera were analyzed from each bird. Results: Most ruddy turnstones had pre-existing antibodies to avian influenza virus, and many were infected at the time of capture. The infectious doses for each challenge virus were similar (103·6–104·16 EID50), regardless of exposure history. All infected birds excreted similar amounts of virus and showed no clinical signs of disease or mortality. Influenza A-specific antibodies remained detectable for at least 2 months after inoculation. Conclusions: These results provide a reference for interpretation of surveillance data, modeling, and predicting the risks of avian influenza transmission and movement in these important hosts.

  19. An ultrasonic study of experimental infected hydronephrosis in rabbit

    International Nuclear Information System (INIS)

    Choi, Byung Ihn; Yu, Yun Jeong; Han, Man Chung; Kim, Chu Wan

    1983-01-01

    Ultrasonography of rabbit kidney was performed after induction of infected hydronephrosis to evaluate the sequential sonographic changes in 15 rabbits. Infected hydronephrosis was induced by ligation of the distal ureter and ureteral inoculation of Escherichia coli. Ultrasonography was performed daily during the first two weeks and weekly during the following 4 weeks after induction of infected hydronephrosis. The results are as follows: 1. The earliest abnormal ultrasonographic findings was appearance of internal echoes in dependent portion of the pelvis, which appeared within 4 days after inoculation in all cases. 2. Degree of internal echoes within the pelvis increased progressively with lapse of time and the entire pelvis was filled with internal echoes within 2 weeks after inoculation in all cases. 3. Echogenecity of internal echoes within the pelvis was similar to that of renal parenchyma in the first week after inoculation, however was weaker than that of renal parenchyma 2 weeks after inoculation in all cases

  20. Lactobacillus paracasei feeding improves the control of secondary experimental meningococcal infection in flu-infected mice.

    Science.gov (United States)

    Belkacem, Nouria; Bourdet-Sicard, Raphaëlle; Taha, Muhamed-Kkeir

    2018-04-10

    The use of probiotics to improve anti-microbial defence, such as for influenza infections, is increasingly recommended. However, no data are available on the effect of probiotics on flu-associated secondary bacterial infections. There is strong evidence of a spatiotemporal association between influenza virus infection and invasive Neisseria meningitidis. We thus investigated the effect of feeding mice Lactobacillus paracasei CNCM I-1518 in a mouse model of sequential influenza-meningococcal infection. We intranasally infected BALB/c mice with a strain of influenza A virus (IAV) H3N2 that was first adapted to mice. Seven days later, a secondary bacterial infection was induced by intranasal administration of bioluminescent N. meningitidis. During the experiment, mice orally received either L. paracasei CNCM I-1518 or PBS as a control. The effect of L. paracasei administration on secondary bacterial infection by N. meningitidis was evaluated. Oral consumption of L. paracasei CNCM I-1518 reduced the weight loss of infected mice and lowered the bioluminescent signal of infecting meningococci. This improvement was associated with higher recruitment of inflammatory myeloid cells, such as interstitial monocytes and dendritic cells, to the lungs. Our data highlight the role of the gut-lung axis. L. paracasei CNCM I-1518 may boost the defence against IAV infection and secondary bacterial infection, which should be further studied and validated in clinical trials.

  1. Experimental pneumococcal meningitis in mice: a model of intranasal infection

    NARCIS (Netherlands)

    Zwijnenburg, P. J.; van der Poll, T.; Florquin, S.; van Deventer, S. J.; Roord, J. J.; van Furth, A. M.

    2001-01-01

    Effective laboratory animal models of bacterial meningitis are needed to unravel the pathophysiology of this disease. Previous models have failed to simulate human meningitis by using a directly intracerebral route of infection. Hyaluronidase is a virulence factor of Streptococcus pneumoniae. In

  2. Streptococcus agalactiae impairs cerebral bioenergetics in experimentally infected silver catfish.

    Science.gov (United States)

    Baldissera, Matheus D; Souza, Carine F; Parmeggiani, Belisa S; Santos, Roberto C V; Leipnitz, Guilhian; Moreira, Karen L S; da Rocha, Maria Izabel U M; da Veiga, Marcelo L; Baldisserotto, Bernardo

    2017-10-01

    It is becoming evident that bacterial infectious diseases affect brain energy metabolism, where alterations of enzymatic complexes of the mitochondrial respiratory chain and creatine kinase (CK) lead to an impairment of cerebral bioenergetics which contribute to disease pathogenesis in the central nervous system (CNS). Based on this evidence, the aim of this study was to evaluate whether alterations in the activity of complex IV of the respiratory chain and CK contribute to impairment of cerebral bioenergetics during Streptococcus agalactiae infection in silver catfish (Rhamdia quelen). The activity of complex IV of the respiratory chain in brain increased, while the CK activity decreased in infected animals compared to uninfected animals. Brain histopathology revealed inflammatory demyelination, gliosis of the brain and intercellular edema in infected animals. Based on this evidence, S. agalactiae infection causes an impairment in cerebral bioenergetics through the augmentation of complex IV activity, which may be considered an adaptive response to maintain proper functioning of the electron respiratory chain, as well as to ensure ongoing electron flow through the electron transport chain. Moreover, inhibition of cerebral CK activity contributes to lower availability of ATP, contributing to impairment of cerebral energy homeostasis. In summary, these alterations contribute to disease pathogenesis linked to the CNS. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Experimental infection of Ethiopian highland sheep by different ...

    African Journals Online (AJOL)

    adult worm population and the egg excretion positively and significantly correlated together, whereas they were .... Figure 1: Nematode egg excretion from sheep infected with different doses of H. contortus L3. Total worm burden .... further drop in haematological parameters until the end of the experiment. Eosinophils are ...

  4. Progression of experimental chronic Aleutian mink disease virus infection

    DEFF Research Database (Denmark)

    Jensen, Trine Hammer; Chriél, Mariann; Hansen, Mette Sif

    2016-01-01

    Aleutian mink disease virus (AMDV) is found world-wide and has a major impact on mink health and welfare by decreasing reproduction and fur quality. In the majority of mink, the infection is subclinical and the diagnosis must be confirmed by serology or polymerase chain reaction (PCR). Increased ...

  5. Quantification of HTLV-I proviral load in experimentally infected rabbits

    Directory of Open Access Journals (Sweden)

    Kindt Thomas J

    2005-05-01

    Full Text Available Abstract Background Levels of proviral load in HTLV-1 infected patients correlate with clinical outcome and are reasonably prognostic. Adaptation of proviral load measurement techniques is examined here for use in an experimental rabbit model of HTLV-1 infection. Initial efforts sought to correlate proviral load with route and dose of inoculation and with clinical outcome in this model. These methods contribute to our continuing goal of using the model to test treatments that alleviate virus infection. Results A real-time PCR assay was used to measure proviral load in blood and tissue samples from a series of rabbits infected using HTLV-1 inocula prepared as either cell-free virus particles, infected cells or blood, or by naked DNA injection. Proviral loads from asymptomatically infected rabbits showed levels corresponding to those reported for human patients with clinically silent HTLV-1 infections. Proviral load was comparably increased in 50% of experimentally infected rabbits that developed either spontaneous benign or malignant tumors while infected. Similarly elevated provirus was found in organs of rabbits with experimentally induced acute leukemia/lymphoma-like disease. Levels of provirus in organs taken at necropsy varied widely suggesting that reservoirs of infections exist in non-lymphoid organs not traditionally thought to be targets for HTLV-1. Conclusion Proviral load measurement is a valuable enhancement to the rabbit model for HTLV-1 infection providing a metric to monitor clinical status of the infected animals as well as a means for the testing of treatment to combat infection. In some cases proviral load in blood did not reflect organ proviral levels, revealing a limitation of this method for monitoring health status of HTLV-1 infected individuals.

  6. Myxoviruses do not induce non-specific alterations in membrane permeability early on in infection

    International Nuclear Information System (INIS)

    Foster, K.A.; Micklem, K.J.; Bogomolova, N.N.; Boriskin, Y.S.; Pasternak, C.A.

    1983-01-01

    The permeability characteristics of cells infected with myxoviruses have been studied by measuring the concentrative uptake of nutrients, the concentration of intracellular K + , and the maintenance of the Na + gradient across the plasma membrane. Cells either show no change at all (Sendai virus-infected BHK cells and measles virus-infected Vero cells) or they show a decreased ability to concentrate nutrients, while intracellular K + and the Na + gradient remain unchanged (Sendai and influenza virus-infected L-1210 cells, measles virus-infected lymphocytes and mumps virus-infected L-41 cells). In no case, therefore, was a change observed that resembles the non-specific increase in membrane permeability induced by haemolytic paramyxoviruses (35, 42) or the non-specific membrane leakiness postulated to take place in infected cells (8, 9). A preliminary account of some of these findings has been presented (39)

  7. Metabolomic profiling in cattle experimentally infected with Mycobacterium avium subsp. paratuberculosis.

    Directory of Open Access Journals (Sweden)

    Jeroen De Buck

    Full Text Available The sensitivity of current diagnostics for Johne's disease, a slow, progressing enteritis in ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP, is too low to reliably detect all infected animals in the subclinical stage. The objective was to identify individual metabolites or metabolite profiles that could be used as biomarkers of early MAP infection in ruminants. In a monthly follow-up for 17 months, calves infected at 2 weeks of age were compared with aged-matched controls. Sera from all animals were analyzed by 1H nuclear magnetic resonance spectrometry. Spectra were acquired, processed, and quantified for analysis. The concentration of many metabolites changed over time in all calves, but some metabolites only changed over time in either infected or non-infected groups and the change in others was impacted by the infection. Hierarchical multivariate statistical analysis achieved best separation between groups between 300 and 400 days after infection. Therefore, a cross-sectional comparison between 1-year-old calves experimentally infected at various ages with either a high- or a low-dose and age-matched non-infected controls was performed. Orthogonal Projection to Latent Structures Discriminant Analysis (OPLS DA yielded distinct separation of non-infected from infected cattle, regardless of dose and time (3, 6, 9 or 12 months after infection. Receiver Operating Curves demonstrated that constructed models were high quality. Increased isobutyrate in the infected cattle was the most important agreement between the longitudinal and cross-sectional analysis. In general, high- and low-dose cattle responded similarly to infection. Differences in acetone, citrate, glycerol and iso-butyrate concentrations indicated energy shortages and increased fat metabolism in infected cattle, whereas changes in urea and several amino acids (AA, including the branched chain AA, indicated increased protein turnover. In conclusion, metabolomics

  8. [Five steps to decreasing nosocomial infections in large immature premature infants: A quasi-experimental study].

    Science.gov (United States)

    García González, Ana; Leante Castellanos, José Luis; Fuentes Gutiérrez, Carmen; Lloreda García, José María; Fernández Fructuoso, José Ramón; Gómez Santos, Elisabet; García González, Verónica

    2017-07-01

    An evaluation is made of the impact of a series of five interventions on the incidence of hospital-related infections in a level iii neonatal unit. Quasi-experimental, pre-post intervention study, which included preterm infants weighing 1,500g at birth or delivered at <32 weeks gestation, admitted in the 12 months before and after the measures were implemented (January 2014). The measures consisted of: optimising hand washing, following a protocol for insertion and handling of central intravenous catheters, encouraging breastfeeding; applying a protocol for rational antibiotic use, and establishing a surveillance system for multi-resistant bacteria. The primary endpoint was to assess the incidence of hospital-acquired infections before and after implementing the interventions. Thirty-three matched patients were included in each period. There was an incidence of 8.7 and 2.7 hospital-related infections/1,000 hospital stay days in the pre- and post-intervention periods, respectively (P<.05). Additionally, patients in the treatment group showed a statistically-significant decrease in days on mechanical ventilation, use of blood products, and vasoactive drugs. The strategy, based on implementing five specific measures in a unit with a high rate of hospital-related infections, proved effective in reducing their incidence. This reduction could contribute to lowering the use of mechanical ventilation, blood products, and vasoactive drugs. Copyright © 2016 Asociación Española de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

  9. Brain infection following experimental Staphylococcus aureus sepsis in pigs

    DEFF Research Database (Denmark)

    Astrup, Lærke Boye; Iburg, Tine Moesgaard; Nielsen, Ole Lerberg

    2010-01-01

    Introduction: Sepsis is a major problem in humans and both the incidence and mortality is increasing. Multiple microabcesses can be found in the brain of septic patients. Staphylococcus aureus is one of the most common causes of sepsis and brain abscesses. S. aureus is also a frequent cause...... of spontaneous porcine pyemia including endocarditis and associated brain lesions. We present a porcine model of haematogenous S. aureus induced brain infection. Materials and Methods: Twelve pigs received an intravenous injection of S. aureus of 108 CFU/kg body weight once at 0h or twice at 0h and 12h. Four...... pigs were kept as controls. The pigs were euthanized in groups of four at either 6, 12, 24 or 48 h post infection. The brain was collected from all the animals and examined histologically. Results: All the inoculated pigs developed sepsis and 7 out of 12 animals had microabscesses in the prosencephalon...

  10. Food additives and Hymenolepis nana infection: an experimental study.

    Science.gov (United States)

    El-Nouby, Kholoud A; Hamouda, Hala E; Abd El Azeem, Mona A; El-Ebiary, Ahmad A

    2009-12-01

    The effect of sodium benzoate (SB) on the pathogenesis of Hymenolepis nana (H. nana) and its neurological manifestations was studied in the present work. One hundred and thirty five mice were classified into three groups. GI: received SB alone. GII: received SB before & after infection with H. nana and GIII: infected with H. nana. All groups were subjected to parasitological, histopathological, immunohistochemical and biochemical assays. The results revealed a significant decrease in IL-4 serum level with a significant increase in gamma amino butyric acid (GABA) and decrease in zinc brain levels in GI, while GII showed non significant increase in IL-4 level that resulted in a highly significant increase in the mean number of cysticercoids and adult worms with delayed expulsion as compared to GIII. This was reflected on histopathological and immunohistochemical changes in the brain. Also, there was a highly significant increase in GABA and decrease in zinc brain levels in GII to the degree that induced behavioral changes. This emphasizes the possible synergistic effect of SB on the neurological manifestations of H. nana and could, in part, explain the increased incidence of behavioral changes in children exposed to high doses of SB and unfortunately have H. nana infection.

  11. Growth performance of broilers in experimental Reovirus infections

    Directory of Open Access Journals (Sweden)

    Sudhakar P. Awandkar

    Full Text Available Background: The avian reoviruses have emerged to induce various manifestations in chickens. They are associated with disease conditions including malabsorption syndrome, tenosynovitis etc. Reoviruses are an important cause of suboptimum performance in broilers, resulting in poor growth performance. Poultry industry in India is facing a catastrophe due to such infections which go unnoticed in field due to masking of the symptoms by secondary infections and commonly observed nutritional disorders. Aim: To investigate the effect of reovirus infection on overall performance of broiler birds. Material and Methods: The broiler birds were challenged with homologous strains of malabsorption syndrome and tenosynovitis syndrome of reovirus. The growth performance was recorded. Results and conclusion: The growth performance and immune response to NDV did not differ in the birds challenged with tenosynovitis syndrome strain of reo virus as compared to un challenged birds. However, poor live body weight, feed intake, FCR, PE and BPEI and better serum NDV titres were found in chicks challenged with malabsorption syndrome strain of reovirus as compared to the chicks from control group. [Vet World 2012; 5(11.000: 685-689

  12. Alteration in the endogenous intestinal flora of swiss webster mice by experimental Angiostrongylus costaricensis infection

    Directory of Open Access Journals (Sweden)

    Vandack Nobre

    2004-11-01

    Full Text Available The association between worm infections and bacterial diseases has only recently been emphasized. This study examined the effect of experimental Angiostrongylus costaricensis infection on endogenous intestinal flora of Swiss Webster mice. Eight mice aging six weeks were selected for this experiment. Four were infected with A. costaricensis and the other four were used as controls. Twenty eight days after the worm infection, all mice in both groups were sacrificed and samples of the contents of the ileum and colon were obtained and cultured for aerobic and anaerobic bacteria. In the mice infected with A. costaricensis there was a significant increase in the number of bacteria of the endogenous intestinal flora, accompanied by a decrease in the number of Peptostreptococcus spp. This alteration in the intestinal flora of mice infected by the nematode may help to understand some bacterial infections described in humans.

  13. Experimental infection with Escherichia coli 0149 : F4ac in weaned piglets

    DEFF Research Database (Denmark)

    Jensen, Gerda M.; Frydendahl, Kai; Svendsen, Ove

    2006-01-01

    adhesion test made after slaughter of piglets. However, in an experimental infection study with the purpose to obtain diarrhoeic piglets, it would be an advantage to test for susceptibility prior to experimentation. The Mucin 4 gene on porcine chromosome 13 has been proposed as a candidate gene...... for the production of the specific ETEC F4ab/ac receptor, and a DNA marker-based test has been developed to allow genotyping for ETEC F4ab/ac resistance/susceptibility [Jorgensen, C.B., Cirera, S., Archibald, A.L., Anderson, L., Fredholm, M., Edfors-Lilja, I., 2004. Porcine polymorphisms and methods for detecting...... them. International application published under the patent cooperation treaty (PCT). PCT/DK2003/000807 or WO2004/048606-A2]. The aim of this study was to test an experimental model for ETEC O149:F4ac-induced diarrhoea in piglets, selected for susceptibility towards ETEC O149:F4ac adhesion prior...

  14. Specific Infectious Organisms Associated With Poor Outcomes in Treatment for Hip Periprosthetic Infection.

    Science.gov (United States)

    Cunningham, Daniel J; Kavolus, Joseph J; Bolognesi, Michael P; Wellman, Samuel S; Seyler, Thorsten M

    2017-06-01

    Periprosthetic hip infection treatment remains a significant challenge for orthopedics. Some studies have suggested that methicillin resistance and gram-negative organism type are associated with increased treatment failure. The aim of this research is to determine if specific organisms were associated with poor outcomes in treatment for hip periprosthetic infection. Records were reviewed of all patients between 2005 and 2015 who underwent treatment for infected partial or total hip arthroplasty. Characteristics of each patient's treatment course were determined including baseline characteristics, infecting organism(s), infection status at final follow-up, surgeries for infection, and time in hospital. Baseline characteristics and organisms that were associated with clinical outcomes in univariate analysis were incorporated into multivariable outcomes models. When compared with patients infected with other organism(s), patients infected with the following organisms had significantly decreased infection-free rates: Pseudomonas, methicillin-resistant Staphylococcus aureus (MRSA), and Proteus. Infection with certain organisms was associated with 1.13-2.58 additional surgeries: methicillin-sensitive S aureus, coagulase-negative Staphylococcus, MRSA, Pseudomonas, Peptostreptococcus, Klebsiella, Candida, diphtheroids, Propionibacterium acnes, and Proteus species. Specific organisms were associated with 8.56-24.54 additional days in hospital for infection: methicillin-sensitive S aureus, coagulase-negative Staphylococcus, Proteus, MRSA, Enterococcus, Pseudomonas, Klebsiella, beta-hemolytic Streptococcus, and diphtheroids. Higher comorbidity score was also associated with greater length of hospitalization. MRSA, Pseudomonas, and Proteus were associated with all 3 outcomes of lower infection-free rate, more surgery, and more time in hospital in treatment for hip periprosthetic infection. Organism-specific outcome information may help individualize patient

  15. Combination of anti-retroviral drugs and radioimmunotherapy specifically kills infected cells from HIV infected individuals

    Directory of Open Access Journals (Sweden)

    Dina Tsukrov

    2016-09-01

    Full Text Available Eliminating virally infected cells is an essential component of any HIV eradication strategy. Radioimmunotherapy (RIT, a clinically established method for killing cells using radiolabeled antibodies, was recently applied to target HIV-1 gp41 antigen expressed on the surface of infect-ed cells. Since gp41 expression by infected cells is likely down-regulated in patients on an-tiretroviral therapy (ART, we evaluated the ability of RIT to kill ART-treated infected cells us-ing both in vitro models and lymphocytes isolated from HIV-infected subjects. Human peripheral blood mononuclear cells (PBMCs were infected with HIV and cultured in the presence of two clinically relevant ART combinations. Scatchard analysis of the 2556 human monoclonal anti-body to HIV gp41 binding to the infected and ART-treated cells demonstrated sufficient residual expression of gp41 on the cell surface to warrant subsequent RIT. This is the first time the quantification of gp41 post-ART is being reported. Cells were then treated with Bismuth-213-labeled 2556 antibody. conjugated to the human monoclonal antibody 2556, which binds to HIV gp41. Cell survival was quantified by Trypan blue and residual viremia by p24 ELISA. Cell surface gp41 expression was assessed by Scatchard analysis. The experiments were repeated using PBMCs isolated from blood specimens obtained from 15 HIV-infected individuals: ten on ART and five ART-naive. We found that 213Bi-2556 killed ART-treated infected PBMCs and reduced viral production to undetectable levels. ART and RIT co-treatment was more effective at reducing viral load in vitro than either therapy alone, indicating that gp41 expression under ART was sufficient to allow 213Bi-2556 to deliver cytocidal doses of radiation to infected cells. This study provides proof of concept that 213Bi-2556 may represent an innovative and effective targeting method for killing HIV-infected cells treated with ART, and supports continued development of 213Bi

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

    Science.gov (United States)

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

    2005-09-01

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

  17. Immunodiagnosis of systemic aspergillosis. I. Antigenemia detected by radioimmunoassay in experimental infection. [/sup 125/I tracer technique

    Energy Technology Data Exchange (ETDEWEB)

    Weiner, M.H.; Coats-Stephen, M.

    1979-01-01

    Because systemic aspergillosis is difficult to diagnose ante mortem, a study to improve immunodiagnosis was undertaken in a rabbit model of disseminated infection. We found that the predominant humoral response of infected animals was directed against four Aspergillus antigens identified by crossed immunoelectrophoresis. One of these antigens, a cell-wall carbohydrate, was purified by gel-filtration chromatography and was used to develop a radiommunoassay. The sensitivity of this assay was increased by testing for serum-bound antigen as well as for free antigen. When the sensitivity of the RIA was evaluated in the animal model, antigenemia was detected in 78% of 51 rabbits with disseminated infection and ante mortem in 86% of 42 rabbits with lethal infection. By contrast, with immunoprecipitin analysis only eight of 51 rabbits were positive for antigen, and six of 51 rabbits were positive for Aspergillus antibody. The specificity of the RIA was also tested. Negative controls for antigen included sera from 76 normal rabbits and sera from 25 rabbits with systemic candidiasis. The Candida control group is pertinent because 48% of these rabbits had specific Candida antigenemia detected by a mannan RIA. This study demonstrates that Aspergillus antigenemia occurs during the course of experimental disseminated aspergillosis and illustrates the potential of an Aspergillus antigen RIA for sensitive, specific immunodiagnosis of human infections.

  18. EXPERIMENTAL-INFECTION IN MICE WITH BACILLUS-LICHENIFORMIS

    DEFF Research Database (Denmark)

    Agerholm, J.S.; Jensen, H.E.; Jensen, N.E.

    1995-01-01

    The pathogenicity of Bacillus licheniformis was assessed in normal and immunodepressed BALB/c mice. The animals were challenged intravenously with 4 x 10(7) colony forming units of B, licheniformis (ATCC 14580) and both normal and immunodepressed mice were susceptible. However, the infection...... was more severe in the immunosuppressed animals. In normal mice, lesions were restricted to the liver and kidneys, while lesions also occurred in other organs of immunodepressed mice. By crossed immunoelectrophoresis it was shown that antigens of B. licheniformis are potent immunogens, and the bacteria...

  19. Genetic variability of Taenia solium cysticerci recovered from experimentally infected pigs and from naturally infected pigs using microsatellite markers.

    Science.gov (United States)

    Pajuelo, Mónica J; Eguiluz, María; Roncal, Elisa; Quiñones-García, Stefany; Clipman, Steven J; Calcina, Juan; Gavidia, Cesar M; Sheen, Patricia; Garcia, Hector H; Gilman, Robert H; Gonzalez, Armando E; Zimic, Mirko

    2017-12-01

    The adult Taenia solium, the pork tapeworm, usually lives as a single worm in the small intestine of humans, its only known definitive host. Mechanisms of genetic variation in T. solium are poorly understood. Using three microsatellite markers previously reported [1], this study explored the genetic variability of T. solium from cysts recovered from experimentally infected pigs. It then explored the genetic epidemiology and transmission in naturally infected pigs and adult tapeworms recovered from human carriers from an endemic rural community in Peru. In an initial study on experimental infection, two groups of three piglets were each infected with proglottids from one of two genetically different tapeworms for each of the microsatellites. After 7 weeks, pigs were slaughtered and necropsy performed. Thirty-six (92.3%) out of 39 cysts originated from one tapeworm, and 27 (100%) out of 27 cysts from the other had exactly the same genotype as the parental tapeworm. This suggests that the microsatellite markers may be a useful tool for studying the transmission of T. solium. In the second study, we analyzed the genetic variation of T. solium in cysts recovered from eight naturally infected pigs, and from adult tapeworms recovered from four human carriers; they showed genetic variability. Four pigs had cysts with only one genotype, and four pigs had cysts with two different genotypes, suggesting that multiple infections of genetically distinct parental tapeworms are possible. Six pigs harbored cysts with a genotype corresponding to one of the identified tapeworms from the human carriers. In the dendrogram, cysts appeared to cluster within the corresponding pigs as well as with the geographical origin, but this association was not statistically significant. We conclude that genotyping of microsatellite size polymorphisms is a potentially important tool to trace the spread of infection and pinpoint sources of infection as pigs spread cysts with a shared parental genotype.

  20. Genetic variability of Taenia solium cysticerci recovered from experimentally infected pigs and from naturally infected pigs using microsatellite markers.

    Directory of Open Access Journals (Sweden)

    Mónica J Pajuelo

    2017-12-01

    Full Text Available The adult Taenia solium, the pork tapeworm, usually lives as a single worm in the small intestine of humans, its only known definitive host. Mechanisms of genetic variation in T. solium are poorly understood. Using three microsatellite markers previously reported [1], this study explored the genetic variability of T. solium from cysts recovered from experimentally infected pigs. It then explored the genetic epidemiology and transmission in naturally infected pigs and adult tapeworms recovered from human carriers from an endemic rural community in Peru. In an initial study on experimental infection, two groups of three piglets were each infected with proglottids from one of two genetically different tapeworms for each of the microsatellites. After 7 weeks, pigs were slaughtered and necropsy performed. Thirty-six (92.3% out of 39 cysts originated from one tapeworm, and 27 (100% out of 27 cysts from the other had exactly the same genotype as the parental tapeworm. This suggests that the microsatellite markers may be a useful tool for studying the transmission of T. solium. In the second study, we analyzed the genetic variation of T. solium in cysts recovered from eight naturally infected pigs, and from adult tapeworms recovered from four human carriers; they showed genetic variability. Four pigs had cysts with only one genotype, and four pigs had cysts with two different genotypes, suggesting that multiple infections of genetically distinct parental tapeworms are possible. Six pigs harbored cysts with a genotype corresponding to one of the identified tapeworms from the human carriers. In the dendrogram, cysts appeared to cluster within the corresponding pigs as well as with the geographical origin, but this association was not statistically significant. We conclude that genotyping of microsatellite size polymorphisms is a potentially important tool to trace the spread of infection and pinpoint sources of infection as pigs spread cysts with a shared

  1. Detection of toxoplasma gondii antigens in sera from experimentally infected mice

    International Nuclear Information System (INIS)

    Shojaee, S.; Keshavarz, H.; Rezaian, M.; Mohebali, M.

    2007-01-01

    Detection of Toxoplasma antigen in serum of mice by Immunoblotting. strain. IgG isolated from rabbits that were immunized with T. gondii Immunoblotting was performed to detect T. gondii antigens in sera of mice. Serum samples from mice experimentally infected with T. gondii RH strain. The value of Immunoblotting in diagnosis of toxoplasmosis in acute stage of infection. The antigen bands detected in serum sample of mice were experimentally infected with T. gondii tachyzoite in immunoblotting. Six bands demonstrated on seventh post infection day six bands were identified. Similarly on sixth day four bands, on day five three bands and on fourth post infection day two bands were identified. No band was detected in control group sera. Immunoblotting is a sensitive method for diagnosis of acute stage of toxoplasmosis. (author)

  2. Serum levels of cytokines in water buffaloes experimentally infected with Fasciola gigantica.

    Science.gov (United States)

    Zhang, Fu-Kai; Guo, Ai-Jiang; Hou, Jun-Ling; Sun, Miao-Miao; Sheng, Zhao-An; Zhang, Xiao-Xuan; Huang, Wei-Yi; Elsheikha, Hany M; Zhu, Xing-Quan

    2017-09-15

    Fasciola gigantica infection in water buffaloes causes significant economic losses especially in developing countries. Although modulation of the host immune response by cytokine neutralization or vaccination is a promising approach to control infection with this parasite, our understanding of cytokine's dynamic during F. gigantica infection is limited. To address this, we quantified the levels of serum cytokines produced in water buffaloes following experimental infection with F. gigantica. Five buffaloes were infected via oral gavage with 500 viable F. gigantica metacercariae and blood samples were collected from buffaloes one week before infection and for 13 consecutive weeks thereafter. The levels of 10 cytokines in serum samples were simultaneously determined using ELISA. F. gigantica failed to elicit the production of various pro-inflammatory cytokines, including interleukin-1β (IL-1β), IL-2, IL-6, IL-12, and IFN-γ. On the other hand, evidence of a Th2 type response was detected, but only early in the course of parasite colonization and included modest increase in the levels of IL-10 and IL-13. The results also revealed suppression of the immune responses as a feature of chronic F. gigantica infection in buffaloes. Taken together, F. gigantica seems to elicit a modest Th2 response at early stage of infection in order to downregulate harmful Th1- and Th17-type inflammatory responses in experimentally infected buffaloes. The full extent of anti-F. gigantica immune response and its relation to pathogenesis requires further study. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Experimental toxoplasma gondii infection in grey seals (Halichoerus grypus)

    DEFF Research Database (Denmark)

    Gajadhar, A. A.; Measures, L.; Forbes, L. B.

    2004-01-01

    Laboratory-reared animals were used to assess the susceptibility of seals (Halichoerus grypus) to Toxoplasma gondii infection. Four seals were each orally inoculated with 100 or 10,000 oocysts of T. gondii (VEG strain), and another 4 seals served as negative controls. Occasionally, mild behavioral...... changes were observed in all inoculated seals but not in control animals. A modified agglutination test revealed the presence of antibodies to T. gondii in sera collected from inoculated seals and mice inoculated as controls. No evidence of the parasite was found on an extensive histological examination...... of seal tissues, and immunohistochemical staining of tissue sections from inoculated seals revealed a single tissue cyst in only 1 seal. Control mice inoculated with 10 oocysts from the same inoculum given to seals became serologically and histologically positive for T. gondii. Cats that were fed brain...

  4. Genetic Resistance to Scrapie Infection in Experimentally Challenged Goats

    Science.gov (United States)

    Lacroux, Caroline; Perrin-Chauvineau, Cécile; Corbière, Fabien; Aron, Naima; Aguilar-Calvo, Patricia; Torres, Juan Maria; Costes, Pierrette; Brémaud, Isabelle; Lugan, Séverine; Schelcher, François; Barillet, Francis

    2014-01-01

    In goats, several field studies have identified coding mutations of the gene encoding the prion protein (I/M142, N/D146, S/D146, R/Q211, and Q/K222) that are associated with a lower risk of developing classical scrapie. However, the data related to the levels of resistance to transmissible spongiform encephalopathies (TSEs) of these different PRNP gene mutations are still considered insufficient for developing large-scale genetic selection against scrapie in this species. In this study, we inoculated wild-type (WT) PRNP (I142R154R211Q222) goats and homozygous and/or heterozygous I/M142, R/H154, R/Q211, and Q/K222 goats with a goat natural scrapie isolate by either the oral or the intracerebral (i.c.) route. Our results indicate that the I/M142 PRNP polymorphism does not provide substantial resistance to scrapie infection following intracerebral or oral inoculation. They also demonstrate that H154, Q211, and K222 PRNP allele carriers are all resistant to scrapie infection following oral exposure. However, in comparison to WT animals, the H154 and Q211 allele carriers displayed only moderate increases in the incubation period following i.c. challenge. After i.c. challenge, heterozygous K222 and a small proportion of homozygous K222 goats also developed the disease, but with incubation periods that were 4 to 5 times longer than those in WT animals. These results support the contention that the K222 goat prion protein variant provides a strong but not absolutely protective effect against classical scrapie. PMID:24284317

  5. Evaluation of metaphylactic RNA interference to prevent equine herpesvirus type 1 infection in experimental herpesvirus myeloencephalopathy in horses.

    Science.gov (United States)

    Perkins, Gillian A; Van de Walle, Gerlinde R; Pusterla, Nicola; Erb, Hollis N; Osterrieder, Nikolaus

    2013-02-01

    To evaluate metaphylactic RNA interference to prevent equine herpesvirus type 1 (EHV-1) infection in experimental herpesvirus myeloencephalopathy in horses and to determine whether horses infected with a neuropathogenic strain of the virus that develop equine herpesvirus myeloencephalopathy (EHM) have differences in viremia. 13 seronegative horses. EHV-1 strain Ab4 was administered intranasally on day 0, and small interfering RNAs (siRNAs [EHV-1 specific siRNAs {n = 7} or an irrelevant siRNA {6}]) were administered intranasally 24 hours before and 12, 24, 36, and 48 hours after infection. Physical and neurologic examinations, nasal swab specimens, and blood samples were collected for virus isolation and quantitative PCR assay. Data from the study were combined with data from a previous study of 14 horses. No significant difference was detected in clinical variables, viremia, or detection of EHV-1 in nasal swab specimens of horses treated with the EHV-1 targeted siRNAs (sigB3-siOri2) versus controls. No significant differences in viremia were detected between horses that developed EHM and those that did not. Administration of siRNAs targeted against EHV-1 around the time of EHV-1 infection was not protective with this experimental design. Horses infected with the neuropathogenic EHV-1 strain Ab4 that developed EHM did not have a more pronounced viremia.

  6. HoBi-like pestivirus experimental infection in pregnant ewes: Reproductive disorders and generation of persistently infected lambs.

    Science.gov (United States)

    Decaro, Nicola; Losurdo, Michele; Larocca, Vittorio; Lucente, Maria Stella; Mari, Viviana; Varello, Katia; Patruno, Giovanni; Camero, Michele; Sciarra, Marina; Occhiogrosso, Leonardo; Tempesta, Maria; Iulini, Barbara; Buonavoglia, Canio

    2015-08-05

    In order to evaluate sheep as experimental model to test the efficacy of HoBi-like pestivirus vaccines for cattle, 10 sheep at different stages of pregnancy (30 or 50 days) were experimentally infected with the Italian prototype isolate Italy-1/10-1. Irrespective of the stage of pregnancy, virus inoculation resulted in reproductive failures, consisting of abortion, stillbirths or birth of weak or persistently infected (PI) lambs. Aborted fetuses, stillborn and dead lambs displayed extensive histopathological changes, consisting of hemorrhages, congestion and mononuclear infiltration in major organs. Pestiviral antigens were detected by immunohistochemistry in most tissues with remarkable signals in lungs and kidneys. PI lambs were constantly viremic, shed the virus through the nasal secretions and feces and, in all cases but one, did not have detectable HoBi-like pestivirus antibodies before the assumption of colostrum. The single seropositive infected lamb showed low-titer viremia and viral shedding that ceased only several weeks after the 3-month observation period. The study proves that sheep are susceptible to the reproduction failures caused by HoBi-like pestivirus infection and can serve as a suitable model for the evaluation of the fetal protection induced by homologous experimental vaccines. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Organization and Biology of the Porcine Serum Amyloid A (SAA) Gene Cluster: Isoform Specific Responses to Bacterial Infection

    DEFF Research Database (Denmark)

    Olsen, Helle G; Skovgaard, Kerstin; Nielsen, Ole L

    2013-01-01

    Serum amyloid A (SAA) is a prominent acute phase protein. Although its biological functions are debated, the wide species distribution of highly homologous SAA proteins and their uniform behavior in response to injury or inflammation in itself suggests a significant role for this protein. The pig...... is increasingly being used as a model for the study of inflammatory reactions, yet only little is known about how specific SAA genes are regulated in the pig during acute phase responses and other responses induced by pro-inflammatory host mediators. We designed SAA gene specific primers and quantified the gene...... expression of porcine SAA1, SAA2, SAA3, and SAA4 by reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) in liver, spleen, and lung tissue from pigs experimentally infected with the Gram-negative swine specific bacterium Actinobacillus pleuropneumoniae, as well as from pigs experimentally...

  8. Youth's perceptions of HIV infection risk: a sex-specific test of two ...

    African Journals Online (AJOL)

    Youth's perceptions of HIV infection risk: a sex-specific test of two risk models. ... The analysis is based on data from the 2003 Demographic and Health survey ... multiple partners, Nigeria, risk perception, sexual behaviour, vulnerability to HIV ...

  9. Adaptation of Lymnaea fuscus and Radix balthica to Fasciola hepatica through the experimental infection of several successive snail generations

    Science.gov (United States)

    2014-01-01

    Background High prevalence of Fasciola hepatica infection (>70%) was noted during several outbreaks before the 2000s in several French farms where Galba truncatula is lacking. Other lymnaeids such as Lymnaea fuscus, L. glabra and/or Radix balthica are living in meadows around these farms but only juvenile snails can sustain complete larval development of F. hepatica while older snails were resistant. The low prevalence of infection (<20%) and limited cercarial production (<50 cercariae per infected snail) noted with these juveniles could not explain the high values noted in these cattle herds. As paramphistomosis due to Calicophoron daubneyi was not still noted in these farms, the existence of another mode of infection was hypothesized. Experimental infection of several successive generations of L. glabra, originating from eggs laid by their parents already infected with this parasite resulted in a progressive increase in prevalence of snail infection and the number of shed cercariae. The aim of this paper was to determine if this mode of snail infection was specific to L. glabra, or it might occur in other lymnaeid species such as L. fuscus and R. balthica. Methods Five successive generations of L. fuscus and R. balthica were subjected to individual bimiracidial infections in the laboratory. Resulting rediae and cercariae in the first four generations were counted after snail dissection at day 50 p.e. (20°C), while the dynamics of cercarial shedding was followed in the F5 generation. Results In the first experiment, prevalence and intensity of F. hepatica infection in snails progressively increased from the F1 (R. balthica) or F2 (L. fuscus) generation. In the second experiment, the prevalence of F. hepatica infection and the number of shed cercariae were significantly lower in L. fuscus and R. balthica (without significant differences between both lymnaeids) than in G. truncatula. Conclusion The F. hepatica infection of several successive snail generations

  10. Histopathological study of experimental and natural infections by Trypanosoma cruzi in Didelphis marsupialis

    Directory of Open Access Journals (Sweden)

    João Carlos Araujo Carreira

    1996-10-01

    Full Text Available Didelphis marsupialis, the most important sylvatic reservoir of Trypanosoma cruzi, can also maintain in their anal scent glands the multiplicative forms only described in the intestinal tract of triatomine bugs. A study of 21 experimentally and 10 naturally infected opossums with T. cruzi was undertaken in order to establish the histopathological pattern under different conditions. Our results showed that the inflammation was predominantly lymphomacrophagic and more severe in the naturally infected animals but never as intense as those described in Chagas' disease or in other animal models. The parasitism in both groups was always mild with very scarce amastigote nests in the tissues. In the experimentally infected animals, the inflammation was directly related to the presence of amastigotes nests. Four 24 days-old animals, still in embryonic stage, showed multiple amastigotes nests and moderate inflammatory reactions, but even so they survived longer and presented less severe lesions than experimentally infected adult mice. Parasites were found in smooth, cardiac and/or predominantly striated muscles, as well as in nerve cells. Differing from the experimentally infected opossums parasitism in the naturally infected animals predominated in the heart, esophagus and stomach. Parasitism of the scent glands did not affect the histopathological pattern observed in extraglandular tissues.

  11. Isolation of Trichophyton mentogrophytes var mentogrophytes from naturally infected laboratory albino rats: experimental infection and treatment in rabbits

    Directory of Open Access Journals (Sweden)

    N. A. Issa

    2009-01-01

    Full Text Available The present study demonstrated for the first time the occurrence of dermatophytosis in naturally infected rats and from asymptomatic and from breeding boxes of white rats kept in animal housing of college of Veterinary Medicine, University of Dohuk, Iraq. The prevalence rate of infection was (28%, clinically infected rats characterized by appearance of scaly ovoid type lesions with crusty edge and patch of hair loss mostly seen on the back, neck and face of the infected rats, itching was reported in some rats. Only one species of the trichophyton, T. mentogrophytes var mentogrophytes was isolated with growth rate (85.71% of samples collected from clinically infected rats, and (28.57% from asymptomatic and from breeding cages, the growth was observed within the 21 days at 25ºC on Sabouraud's Dextrose Agar. Lacto phenol cotton blue staining slides of T. mentogrophytes var mentogrophytes revealed both microconidia and macroconidia. Microconidia found in numerous numbers often in dense cluster which were hyaline, smooth walled and predominantly spherical to sub spherical in shape, varying numbers of chlamydoconidia. Spiral hyphae and smooth, thin walled clavate shaped multicelled macroconidia were also present. The study also dealt with experimental infection in rabbits with T. mentogrophytes var mentogrophytes and treated by two drugs, natural herbal preparation of acidic pomegranate (Punica granatum fruit and synthetic nystatine ointment. The complete recovery of lesions was recorded after 14 days and 21 days of topical application of a pomegranate and nystatine ointment for 5 successive days respectively.

  12. Antigen-specific and non-specific CD4+ T cell recruitment and proliferation during influenza infection

    International Nuclear Information System (INIS)

    Chapman, Timothy J.; Castrucci, Maria R.; Padrick, Ryan C.; Bradley, Linda M.; Topham, David J.

    2005-01-01

    To track epitope-specific CD4 + T cells at a single-cell level during influenza infection, the MHC class II-restricted OVA 323-339 epitope was engineered into the neuraminidase stalk of influenza/A/WSN, creating a surrogate viral antigen. The recombinant virus, influenza A/WSN/OVA II , replicated well, was cleared normally, and stimulated both wild-type and DO11.10 or OT-II TCR transgenic OVA-specific CD4 + T cells. OVA-specific CD4 T cells proliferated during infection only when the OVA epitope was present. However, previously primed (but not naive) transgenic CD4 + T cells were recruited to the infected lung both in the presence and absence of the OVA 323-339 epitope. These data show that, when primed, CD4 + T cells may traffic to the lung in the absence of antigen, but do not proliferate. These results also document a useful tool for the study of CD4 T cells in influenza infection

  13. Mixed infections reveal virulence differences between host-specific bee pathogens.

    Science.gov (United States)

    Klinger, Ellen G; Vojvodic, Svjetlana; DeGrandi-Hoffman, Gloria; Welker, Dennis L; James, Rosalind R

    2015-07-01

    Dynamics of host-pathogen interactions are complex, often influencing the ecology, evolution and behavior of both the host and pathogen. In the natural world, infections with multiple pathogens are common, yet due to their complexity, interactions can be difficult to predict and study. Mathematical models help facilitate our understanding of these evolutionary processes, but empirical data are needed to test model assumptions and predictions. We used two common theoretical models regarding mixed infections (superinfection and co-infection) to determine which model assumptions best described a group of fungal pathogens closely associated with bees. We tested three fungal species, Ascosphaera apis, Ascosphaera aggregata and Ascosphaera larvis, in two bee hosts (Apis mellifera and Megachile rotundata). Bee survival was not significantly different in mixed infections vs. solo infections with the most virulent pathogen for either host, but fungal growth within the host was significantly altered by mixed infections. In the host A. mellifera, only the most virulent pathogen was present in the host post-infection (indicating superinfective properties). In M. rotundata, the most virulent pathogen co-existed with the lesser-virulent one (indicating co-infective properties). We demonstrated that the competitive outcomes of mixed infections were host-specific, indicating strong host specificity among these fungal bee pathogens. Published by Elsevier Inc.

  14. Therapeutic effect of cefozopran (SCE-2787), a new parenteral cephalosporin, against experimental infections in mice.

    Science.gov (United States)

    Iizawa, Y; Okonogi, K; Hayashi, R; Iwahi, T; Yamazaki, T; Imada, A

    1993-01-01

    The therapeutic effect of cefozopran (SCE-2787), a new semisynthetic parenteral cephalosporin, against experimental infections in mice was examined. Cefozopran was more effective than cefpiramide and was as effective as ceftazidime and cefpirome against acute respiratory tract infections caused by Klebsiella pneumoniae DT-S. In the model of chronic respiratory tract infection caused by K. pneumoniae 27, cefozopran was as effective as ceftazidime. The therapeutic effect of cefozopran against urinary tract infections caused by Pseudomonas aeruginosa P9 was superior to that of cefpirome and was equal to those of ceftazidime and cefclidin. In addition, cefozopran was more effective than ceftazidime and was as effective as flomoxef in a thigh muscle infection caused by methicillin-sensitive Staphylococcus aureus 308A-1. Against thigh muscle infections caused by methicillin-resistant S. aureus N133, cefozopran was the most effective agent. The potent therapeutic effect of cefozopran in those experimental infections in mice suggests that it would be effective against respiratory tract, urinary tract, and soft tissue infections caused by a variety of gram-positive and gram-negative bacteria in humans. PMID:8431004

  15. Evaluation of potassium permanganate against an experimental subacute infection of Flavobacterium columnare in channel catfish, Icatlurus punctatus

    Science.gov (United States)

    The efficacy of potassium permanganate (KMnO4) as a prophylactic and therapeutic treatment for subacute infection of Flavobacterium columnare was demonstrated in experimentally infected channel catfish, Ictalurus punctatus. Catfish experimentally infected with F. columnare to mimic a subacute infec...

  16. Highly (H5N1 and low (H7N2 pathogenic avian influenza virus infection in falcons via nasochoanal route and ingestion of experimentally infected prey.

    Directory of Open Access Journals (Sweden)

    Kateri Bertran

    Full Text Available An experimental infection with highly pathogenic avian influenza (HPAI and low pathogenic avian influenza (LPAI viruses was carried out on falcons in order to examine the effects of these viruses in terms of pathogenesis, viral distribution in tissues and viral shedding. The distribution pattern of influenza virus receptors was also assessed. Captive-reared gyr-saker (Falco rusticolus x Falco cherrug hybrid falcons were challenged with a HPAI H5N1 virus (A/Great crested grebe/Basque Country/06.03249/2006 or a LPAI H7N2 virus (A/Anas plathyrhynchos/Spain/1877/2009, both via the nasochoanal route and by ingestion of previously infected specific pathogen free chicks. Infected falcons exhibited similar infection dynamics despite the different routes of exposure, demonstrating the effectiveness of in vivo feeding route. H5N1 infected falcons died, or were euthanized, between 5-7 days post-infection (dpi after showing acute severe neurological signs. Presence of viral antigen in several tissues was confirmed by immunohistochemistry and real time RT-PCR (RRT-PCR, which were generally associated with significant microscopical lesions, mostly in the brain. Neither clinical signs, nor histopathological findings were observed in any of the H7N2 LPAI infected falcons, although all of them had seroconverted by 11 dpi. Avian receptors were strongly present in the upper respiratory tract of the falcons, in accordance with the consistent oral viral shedding detected by RRT-PCR in both H5N1 HPAI and H7N2 LPAI infected falcons. The present study demonstrates that gyr-saker hybrid falcons are highly susceptible to H5N1 HPAI virus infection, as previously observed, and that they may play a major role in the spreading of both HPAI and LPAI viruses. For the first time in raptors, natural infection by feeding on infected prey was successfully reproduced. The use of avian prey species in falconry husbandry and wildlife rehabilitation facilities could put valuable birds

  17. Highly (H5N1) and low (H7N2) pathogenic avian influenza virus infection in falcons via nasochoanal route and ingestion of experimentally infected prey.

    Science.gov (United States)

    Bertran, Kateri; Busquets, Núria; Abad, Francesc Xavier; García de la Fuente, Jorge; Solanes, David; Cordón, Iván; Costa, Taiana; Dolz, Roser; Majó, Natàlia

    2012-01-01

    An experimental infection with highly pathogenic avian influenza (HPAI) and low pathogenic avian influenza (LPAI) viruses was carried out on falcons in order to examine the effects of these viruses in terms of pathogenesis, viral distribution in tissues and viral shedding. The distribution pattern of influenza virus receptors was also assessed. Captive-reared gyr-saker (Falco rusticolus x Falco cherrug) hybrid falcons were challenged with a HPAI H5N1 virus (A/Great crested grebe/Basque Country/06.03249/2006) or a LPAI H7N2 virus (A/Anas plathyrhynchos/Spain/1877/2009), both via the nasochoanal route and by ingestion of previously infected specific pathogen free chicks. Infected falcons exhibited similar infection dynamics despite the different routes of exposure, demonstrating the effectiveness of in vivo feeding route. H5N1 infected falcons died, or were euthanized, between 5-7 days post-infection (dpi) after showing acute severe neurological signs. Presence of viral antigen in several tissues was confirmed by immunohistochemistry and real time RT-PCR (RRT-PCR), which were generally associated with significant microscopical lesions, mostly in the brain. Neither clinical signs, nor histopathological findings were observed in any of the H7N2 LPAI infected falcons, although all of them had seroconverted by 11 dpi. Avian receptors were strongly present in the upper respiratory tract of the falcons, in accordance with the consistent oral viral shedding detected by RRT-PCR in both H5N1 HPAI and H7N2 LPAI infected falcons. The present study demonstrates that gyr-saker hybrid falcons are highly susceptible to H5N1 HPAI virus infection, as previously observed, and that they may play a major role in the spreading of both HPAI and LPAI viruses. For the first time in raptors, natural infection by feeding on infected prey was successfully reproduced. The use of avian prey species in falconry husbandry and wildlife rehabilitation facilities could put valuable birds of prey and

  18. Praziquantel treatment decreases Schistosoma mansoni genetic diversity in experimental infections.

    Directory of Open Access Journals (Sweden)

    Regina Coeli

    Full Text Available BACKGROUND: Schistosomiasis has a considerable impact on public health in many tropical and subtropical areas. In the new world, schistosomiasis is caused by the digenetic trematode Schistosoma mansoni. Chemotherapy is the main measure for controlling schistosomiasis, and the current drug of choice for treatment is praziquantel (PZQ. Although PZQ is efficient and safe, its repetitive large-scale use in endemic areas may lead to the selection of resistant strains. Isolates less susceptible to PZQ have been found in the field and selected for in the laboratory. The impact of selecting strains with a decreased susceptibility phenotype on disease dynamics and parasite population genetics is not fully understood. This study addresses the impact of PZQ pressure on the genetics of a laboratory population by analyzing frequency variations of polymorphic genetic markers. METHODOLOGY: Infected mice were treated with increasing PZQ doses until the highest dose of 3 × 300 mg/Kg was reached. The effect of PZQ treatment on the parasite population was assessed using five polymorphic microsatellite markers. Parasitological and genetic data were compared with those of the untreated control. After six parasite generations submitted to treatment, it was possible to obtain a S. mansoni population with decreased susceptibility to PZQ. In our experiments we also observed that female worms were more susceptible to PZQ than male worms. CONCLUSIONS: The selective pressure exerted by PZQ led to decreased genetic variability in S. mansoni and increased endogamy. The understanding of how S. mansoni populations respond to successive drug pressure has important implications on the appearance and maintenance of a PZQ resistance phenotype in endemic regions.

  19. Antibody responses of cervids (Cervus elaphus) following experimental Mycobacterium bovis infection and the implications for immunodiagnosis.

    Science.gov (United States)

    Harrington, Noel P; Surujballi, Om P; Prescott, John F; Duncan, J Robert; Waters, W Ray; Lyashchenko, Konstantin; Greenwald, Rena

    2008-11-01

    Captive and free-ranging wildlife animals are implicated in the maintenance and transmission of bovine tuberculosis and therefore pose a significant obstacle to eradication of the disease from domestic livestock. The current antemortem diagnostic method, the intradermal tuberculin skin test, is impractical for routine use with many wild animals. Antibody-based assays are particularly attractive because the animals are handled only once and immediate processing of the sample is not required. This report characterizes the antibody responses of red deer-elk hybrids (Cervus elaphus) against Mycobacterium bovis and subsequently evaluates the diagnostic performance of select antigens in a rapid-test format. Sequential serum samples were collected from 10 animals experimentally infected with M. bovis and 5 noninfected animals over a 7-month period postinfection (p.i.). Samples were evaluated by enzyme-linked immunosorbent assays, immunoblot analyses, and multiantigen print immunoassays for seroreactivity to mycobacterial antigens. Although all infected animals produced antibodies to M. bovis protein antigens, there was significant animal-to-animal variation in the kinetics and magnitudes of responses and the antigens recognized. The most frequently recognized antigens included MPB83, ESAT-6, CFP10, and MPB70. Responses to some antigens, such as MPB83, were consistently detected as early as 4 weeks after inoculation, whereas other antigens were detected only much later (>140 days p.i.). Antibody responses were boosted by injection of tuberculin for intradermal tuberculin skin testing. Comparison of single-antigen (fluorescence polarization assay) with multiantigen (CervidTB STAT-PAK) rapid tests demonstrated that a highly sensitive and specific serodiagnostic test for tuberculosis in cervids will require multiple and carefully selected seroreactive antigens covering a broad spectrum of antibody specificities.

  20. Efficacy of different instrumentation techniques on reducing Enterococcus faecalis infection in experimentally infected root canals

    Directory of Open Access Journals (Sweden)

    Ebru Özsezer Demiryürek

    2014-03-01

    Conclusion: This study indicates that instruments with a greater taper play an important role in maximizing the effectiveness of mechanical preparation. However, since using mechanical instrumentation alone is insufficient to completely eliminate root canal infection, the use of complementary antibacterial compounds is necessary.

  1. Identification of proteins specific for human herpesvirus 6-infected human T cells

    International Nuclear Information System (INIS)

    Balachandran, N.; Amelse, R.E.; Zhou, W.W.; Chang, C.K.

    1989-01-01

    Proteins specific for human herpesvirus 6 (HHV-6)-infected human T cells (HSB-2) were examined by using polyclonal rabbit antibodies and monoclonal antibodies against HHV-6-infected cells and human sera. More than 20 proteins and six glycoproteins specific for HHV-6-infected cells were identified from [ 35 S]methionine- and [ 3 H]glucosamine-labeled total-cell extracts. Polyclonal rabbit antibodies immunoprecipitated 33 [ 35 S]methionine-labeled HHV-6-specific polypeptides with approximate molecular weights ranging from 180,000 to 31,000. In immunoprecipitation and Western immunoblot reactions, a patient's serum also recognized more than 30 HHV-6-specific proteins and seven glycoproteins. In contrast, sera from individuals with high-titered antibodies against other human herpesviruses reacted with fewer HHV-6-infected cell proteins, and only a 135,000-M r polypeptide was prominent. Monoclonal antibodies to HHV-6-infected cells reacted with single and multiple polypeptides specific for virus-infected cells and immunoprecipitated three distinct sets of glycoproteins, which were designated gp105k and gp82k, gp116k, gp64k, and gp54k, and gp102k

  2. Identification of proteins specific for human herpesvirus 6-infected human T cells

    International Nuclear Information System (INIS)

    Balachandran, N.; Amelse, R.E.; Zhou, W.W.; Chang, C.K.

    1989-01-01

    Proteins specific for human herpesvirus 6 (HHV-6)-infected human T cells (HSB-2) were examined by using polyclonal rabbit antibodies and monoclonal antibodies against HHV-6-infected cells and human sera. More than 20 proteins and six glycoproteins specific for HHV-6-infected cells were identified from [ 35 S]methionine- and [ 3 H]glucosamine-labeled total-cell extracts. Polyclonal rabbit antibodies immunoprecipitated 33 [ 35 S]methionine-labeled HHV-6-specific polypeptides with approximate molecular weights ranging from 180,000 to 31,000. In immunoprecipitation and Western immunoblot reactions, a patient's serum also recognized more than 30 HHV-6-specific proteins and seven glycoproteins. In contrast, sera from individuals with high-titered antibodies against other human herpes viruses reacted with few HHV-6-infected cell proteins, and only a 135,000-M/sub r/ polypeptide was prominent. Monoclonal antibodies to HHV-6-infected cells reacted with single and multiple polypeptides specific for virus-infected cells and immunoprecipitated three distinct sets of glycoproteins, which were designated gp105K and gp92k, gp116k, gp64k, and gp54k, and gp102k

  3. Evaluation of a simple Theileria annulata culture protocol from experimentally infected bovine whole blood

    Directory of Open Access Journals (Sweden)

    Gharbi M.

    2012-08-01

    Full Text Available We have evaluated a new simple technique using whole blood from experimentally infected cattle for the isolation and cultivation of Theileria annulata. The study was carried out on 20 Holstein-Frisian bovines that had been experimentally infected with a virulent lethal dose of Theileria annulata. This technique has been compared to the classical peripheral blood monocyte isolation with Ficoll carried out on 22 experimentally infected Holstein-Friesian calves. The effectiveness of the reference technique was estimated to 86.4%, whilst the effectiveness of the new technique was 100%. Moreover, this new technique leads to time and money saving estimated to € 3.06 per sample. It decreases the contamination risks by reducing the steps of sample manipulation.

  4. Hematologic profile of hematophagous Desmodus rotundus bats before and after experimental infection with rabies virus

    Directory of Open Access Journals (Sweden)

    Marilene Fernandes de Almeida

    2014-06-01

    Full Text Available Introduction Hematophagous Desmodus rotundus bats play an important role in the rabies lifecycle. This study describes the hematological profile of these bats before and after experimental infection with rabies virus. Methods Cells counts were performed in a Neubauer chamber. Results The average values of erythrocytes and leucocytes counts in blood before experimental infections were 9.97 × 106mm3 and 4.80 × 103mm3, respectively. Neutrophils represented 69.9% of white blood cells and the lymphocytes represented 26.9%. Following the experimental infections, the average numbers of erythrocytes and leucocytes was 9.43 × 106mm3 and 3.98 × 103mm3, respectively. Neutrophils represented 40% of white blood cells and the lymphocytes represented 59%. Conclusions The hematological profile given in this study can serve as reference values for D. rotundus bats.

  5. Persistence of experimental Rocio virus infection in the golden hamster (Mesocricetus auratus

    Directory of Open Access Journals (Sweden)

    Daniele Freitas Henriques

    2012-08-01

    Full Text Available Rocio virus (ROCV is an encephalitic flavivirus endemic to Brazil. Experimental flavivirus infections have previously demonstrated a persistent infection and, in this study, we investigated the persistence of ROCV infection in golden hamsters (Mesocricetus auratus. The hamsters were infected intraperitoneally with 9.8 LD50/0.02 mL of ROCV and later anaesthetised and sacrificed at various time points over a 120-day period to collect of blood, urine and organ samples. The viral titres were quantified by real-time-polymerase chain reaction (qRT-PCR. The specimens were used to infect Vero cells and ROCV antigens in the cells were detected by immunefluorescence assay. The levels of antibodies were determined by the haemagglutination inhibition technique. A histopathological examination was performed on the tissues by staining with haematoxylin-eosin and detecting viral antigens by immunohistochemistry (IHC. ROCV induced a strong immune response and was pathogenic in hamsters through neuroinvasion. ROCV was recovered from Vero cells exposed to samples from the viscera, brain, blood, serum and urine and was detected by qRT-PCR in the brain, liver and blood for three months after infection. ROCV induced histopathological changes and the expression of viral antigens, which were detected by IHC in the liver, kidney, lung and brain up to four months after infection. These findings show that ROCV is pathogenic to golden hamsters and has the capacity to cause persistent infection in animals after intraperitoneal infection.

  6. E-ADA activity in serum of lambs experimentally infected with Haemonchus contortus.

    Science.gov (United States)

    Da Silva, Aleksandro S; Fausto, Guilherme C; Grando, Thirssa H; Cadore, Carlos A; Pimentel, Victor C; Jaques, Jeandre A; Schetinger, Maria R C; Monteiro, Silvia G; Leal, Marta L R

    2013-08-01

    The aim of this study was to evaluate adenosine deaminase (E-ADA) activity in sera of lambs experimentally infected with Haemonchus contortus. We used 12 lambs divided into 2 groups; Group A had 5 healthy, non-infected animals (control) and Group B had 7 healthy animals infected with H. contortus . Lambs were infected orally with 500 larvae (L3) per animal every 2 days, for a period of 20 days, and later the infection was confirmed by examination of feces (eggs per gram [EPG] via fecal egg count). Blood collection was performed at days 0, 20, 40, 60, and 80 post-infection (PI) for analysis of E-ADA activity. Animals in Group A showed negative EPG throughout the experiment unlike those from Group B that had elevated EPG counts. E-ADA activity was reduced in the serum of animals infected with H. contortus when compared to non-infected controls at days 20, 40, 60, and 80 PI. Therefore, it is concluded that infection with H. contortus influences the E-ADA activity in lambs.

  7. Antifungal activity of caspofungin in experimental infective endocarditis caused by Candida albicans.

    Science.gov (United States)

    Victorio, Gerardo Becerra; Bourdon, Lorena Michele Brennan; Benavides, Leonel García; Huerta-Olvera, Selene G; Plascencia, Arturo; Villanueva, José; Martinez-Lopez, Erika; Hernández-Cañaveral, Iván Isidro

    2017-05-01

    Infective endocarditis is a disease characterised by heart valve lesions, which exhibit extracellular matrix proteins that act as a physical barrier to prevent the passage of antimicrobial agents. The genus Candida has acquired clinical importance given that it is increasingly being isolated from cases of nosocomial infections. To evaluate the activity of caspofungin compared to that of liposomal amphotericin B against Candida albicans in experimental infective endocarditis. Wistar rats underwent surgical intervention and infection with strains of C. albicans to develop infective endocarditis. Three groups were formed: the first group was treated with caspofungin, the second with liposomal amphotericin B, and the third received a placebo. In vitro sensitivity was first determined to further evaluate the effect of these treatments on a rat experimental model of endocarditis by semiquantitative culture of fibrinous vegetations and histological analysis. Our semiquantitative culture of growing vegetation showed massive C. albicans colonisation in rats without treatment, whereas rats treated with caspofungin showed significantly reduced colonisation, which was similar to the results obtained with liposomal amphotericin B. The antifungal activity of caspofungin is similar to that of liposomal amphotericin B in an experimental model of infective endocarditis caused by C. albicans.

  8. Effect of some parasitic infection on neurotransmitters in the brain of experimentally infected mice before and after treatment.

    Science.gov (United States)

    Abdel Ghafar, A E; Elkowrany, S E; Salem, S A; Menaisy, A A; Fadel, W A; Awara, W M

    1996-08-01

    The effects of some parasitic infection (bilharziasis, toxocariasis and trichinosis) on the brain of experimentally infected mice were investigated. Eighty animals were classified into four groups, group I contained five non infected animals as a control group. The other groups each contained twenty-five mice infected with Schistosoma mansoni (group II), Toxocara canis (group III) and Trichinella spiralis (group IV). Each infected group was divided into two subgroups (a,b). Subgroup (a) left untreated and subgroups (b) treated by praziquantel (in group II) and mebendazole (in group III and IV). Histopathological and immunological examination using peroxidase antiperoxidase (PAP) technique and neurotransmitters estimation (nor-epinephrine, dopamine and serotonine) were carried. In the untreated animals, there were mild histopathological changes and mild antigenic deposition in subgroups (IIa and IIIa) and marked changes in subgroup (IVa). There were significant decrease in dopamine in subgroup (IIIa), not improved after treatment (subgroup IIIb) and significant decrease in nor-epinephrine and serotonine in subgroup (IVa) improved after treatment in subgroup (IVb). The neurotransmitters changes may explain the motor, behavioural and emotional changes that occurred with these parasites.

  9. Experimental infection of ponies with Sarcocystis fayeri and differentiation from Sarcocystis neurona infections in horses.

    Science.gov (United States)

    Saville, W J A; Dubey, J P; Oglesbee, M J; Sofaly, C D; Marsh, A E; Elitsur, E; Vianna, M C; Lindsay, D S; Reed, S M

    2004-12-01

    Sarcocystis neurona and Sarcocystis fayeri infections are common in horses in the Americas. Their antemortem diagnosis is important because the former causes a neurological disorder in horses, whereas the latter is considered nonpathogenic. There is a concern that equine antibodies to S. fayeri might react with S. neurona antigens in diagnostic tests. In this study, 4 ponies without demonstrable serum antibodies to S. neurona by Western immunoblot were used. Three ponies were fed 1 x 10(5) to 1 x 10(7) sporocysts of S. fayeri obtained from dogs that were fed naturally infected horse muscles. All ponies remained asymptomatic until the termination of the experiment, day 79 postinoculation (PI). All serum samples collected were negative for antibodies to S. neurona using the Western blot at the initial screening, just before inoculation with S. fayeri (day 2) and weekly until day 79 PI. Cerebrospinal fluid samples from each pony were negative for S. neurona antibodies. Using the S. neurona agglutination test, antibodies to S. neurona were not detected in 1:25 dilution of sera from any samples, except that from pony no. 4 on day 28; this pony had received 1 X 10(7) sporocysts. Using indirect immunofluorescence antibody tests (IFATs), 7 serum samples were found to be positive for S. neurona antibodies from 1:25 to 1:400 dilutions. Sarcocystis fayeri sarcocysts were found in striated muscles of all inoculated ponies, with heaviest infections in the tongue. All sarcocysts examined histologically appeared to contain only microcytes. Ultrastructurally, S. fayeri sarcocysts could be differentiated from S. neurona sarcocysts by the microtubules (mt) in villar protrusions on sarcocyst walls; in S. fayeri the mt extended from the villar tips to the pellicle of zoites, whereas in S. neurona the mt were restricted to the middle of the cyst wall. Results indicate that horses with S. fayeri infections may be misdiagnosed as being S. neurona infected using IFAT, and further research

  10. PCR diagnostics underestimate the prevalence of avian malaria (Plasmodium relictum) in experimentally-infected passerines

    Science.gov (United States)

    Jarvi, Susan I.; Schultz, Jeffrey J.; Atkinson, Carter T.

    2002-01-01

    Several polymerase chain reaction (PCR)-based methods have recently been developed for diagnosing malarial infections in both birds and reptiles, but a critical evaluation of their sensitivity in experimentally-infected hosts has not been done. This study compares the sensitivity of several PCR-based methods for diagnosing avian malaria (Plasmodium relictum) in captive Hawaiian honeycreepers using microscopy and a recently developed immunoblotting technique. Sequential blood samples were collected over periods of up to 4.4 yr after experimental infection and rechallenge to determine both the duration and detectability of chronic infections. Two new nested PCR approaches for detecting circulating parasites based on P. relictum 18S rRNA genes and the thrombospondin-related anonymous protein (TRAP) gene are described. The blood smear and the PCR tests were less sensitive than serological methods for detecting chronic malarial infections. Individually, none of the diagnostic methods was 100% accurate in detecting subpatent infections, although serological methods were significantly more sensitive (97%) than either nested PCR (61–84%) or microscopy (27%). Circulating parasites in chronically infected birds either disappear completely from circulation or to drop to intensities below detectability by nested PCR. Thus, the use of PCR as a sole means of detection of circulating parasites may significantly underestimate true prevalence.

  11. Virological and clinico-pathological features of orf virus infection in experimentally infected rabbits and mice.

    Science.gov (United States)

    Cargnelutti, J F; Masuda, E K; Martins, M; Diel, D G; Rock, D L; Weiblen, R; Flores, E F

    2011-01-01

    Many aspects of the biology of orf virus (ORFV) infection remain poorly understood and attempts to establish animal models have yielded conflicting and non-reproducible results. We herein describe the characterization of ORFV infection and disease in rabbits and mice. A protocol of intradermal inoculation was employed to inoculate 10(8.5)TCID₅₀/mL of ORFV strain IA-82 in the skin of ears, of the back and labial commissures. All inoculated rabbits presented a clinical course characterized by erythema, macules, papules/vesicles or pustules that eventually dried originating scabs. Local signs started around days 3 and 4 post-inoculation (pi) and lasted 3-10 days. Virus was recovered from lesions between days 2 and 14pi. Histological examination of lesions revealed focal proliferative dermatitis with ballooning degeneration and eosinophilic intracytoplasmic inclusion bodies in keratinocytes, histological hallmarks of contagious ecthyma in sheep. A similar, albeit milder clinical course occurred in 5/10 inoculated mice; virus was recovered from lesions from three animals. Inoculated lambs - used as controls - developed severe lesions of contagious ecthyma. VN tests performed at day 28pi failed to detect neutralizing antibodies in all inoculated animals. In contrast, convalescent rabbit sera were positive by ELISA at dilutions from 100 to 400. These results show that rabbits are susceptible to ORFV infection and thus may be used to study selected aspects of ORFV biology. Copyright © 2010 Elsevier Ltd. All rights reserved.

  12. Aspects of Toxoplasma Infection on the Reproductive System of Experimentally Infected Rams (Ovis Aries

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    Welber Daniel Zanetti Lopes

    2009-01-01

    Full Text Available Eight reproductive rams with no prior reproductive disease were distributed into three groups of infection with T. gondii: GI, 3 rams, 2.0×105 P strain oocysts; GII, 3 rams, 1.0×106 RH strain tachyzoites; GIII, 2 control rams. Clinical parameters were measured and serological evaluations (IIF were performed. Presence of the parasite in the semen was investigated by PCR and bioassay techniques. The rams presented clinical alterations (hyperthermia and apathy related to toxoplasmosis in both groups infected with Toxoplasma gondii. All the inoculated rams responded to antigenic stimulus, producing antibodies against T. gondii from postinoculation day 5 onwards. In ovine groups I and II, the greatest titers observed were 1 : 4096 and 1 : 8192, respectively. In semen samples collected from these two groups, the presence of T. gondii was detected by bioassay and PCR. This coccidian was isolated (bioassay and PCR in tissue pools (testicles, epididymis, seminal vesicle, and prostrate from two rams infected presenting oocysts and in one presenting tachyzoites.

  13. The Strategy to Survive Primary Malaria Infection: An Experimental Study on Behavioural Changes in Parasitized Birds.

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    Andrey Mukhin

    Full Text Available Avian malaria parasites (Haemosporida, Plasmodium are of cosmopolitan distribution, and they have a significant impact on vertebrate host fitness. Experimental studies show that high parasitemia often develops during primary malaria infections. However, field studies only occasionally reveal high parasitemia in free-living birds sampled using the traditional methods of mist-netting or trapping, and light chronic infections predominate. The reason for this discrepancy between field observation and experimental data remains insufficiently understood. Since mist-netting is a passive capture method, two main parameters determine its success in sampling infected birds in wildlife, i. e. the presence of parasitized birds at a study site and their mobility. In other words, the trapping probability depends on the survival rate of birds and their locomotor activity during infection. Here we test (1 the mortality rate of wild birds infected with Plasmodium relictum (the lineage pSGS1, (2 the changes in their behaviour during presence of an aerial predator, and (3 the changes in their locomotor activity at the stage of high primary parasitemia.We show that some behavioural features which might affect a bird's survival during a predator attack (time of reaction, speed of flush flight and take off angle did not change significantly during primary infection. However, the locomotor activity of infected birds was almost halved compared to control (non-infected birds during the peak of parasitemia. We report (1 the markedly reduced mobility and (2 the 20% mortality rate caused by P. relictum and conclude that these factors are responsible for the underrepresentation of birds in mist nets and traps during the stage of high primary parasitemia in wildlife. This study indicates that the widespread parasite, P. relictum (pSGS1 influences the behaviour of birds during primary parasitemia. Experimental studies combined with field observations are needed to better

  14. The Strategy to Survive Primary Malaria Infection: An Experimental Study on Behavioural Changes in Parasitized Birds

    Science.gov (United States)

    Mukhin, Andrey; Palinauskas, Vaidas; Platonova, Elena; Kobylkov, Dmitry; Vakoliuk, Irina; Valkiūnas, Gediminas

    2016-01-01

    Avian malaria parasites (Haemosporida, Plasmodium) are of cosmopolitan distribution, and they have a significant impact on vertebrate host fitness. Experimental studies show that high parasitemia often develops during primary malaria infections. However, field studies only occasionally reveal high parasitemia in free-living birds sampled using the traditional methods of mist-netting or trapping, and light chronic infections predominate. The reason for this discrepancy between field observation and experimental data remains insufficiently understood. Since mist-netting is a passive capture method, two main parameters determine its success in sampling infected birds in wildlife, i. e. the presence of parasitized birds at a study site and their mobility. In other words, the trapping probability depends on the survival rate of birds and their locomotor activity during infection. Here we test (1) the mortality rate of wild birds infected with Plasmodium relictum (the lineage pSGS1), (2) the changes in their behaviour during presence of an aerial predator, and (3) the changes in their locomotor activity at the stage of high primary parasitemia.We show that some behavioural features which might affect a bird's survival during a predator attack (time of reaction, speed of flush flight and take off angle) did not change significantly during primary infection. However, the locomotor activity of infected birds was almost halved compared to control (non-infected) birds during the peak of parasitemia. We report (1) the markedly reduced mobility and (2) the 20% mortality rate caused by P. relictum and conclude that these factors are responsible for the underrepresentation of birds in mist nets and traps during the stage of high primary parasitemia in wildlife. This study indicates that the widespread parasite, P. relictum (pSGS1) influences the behaviour of birds during primary parasitemia. Experimental studies combined with field observations are needed to better understand the

  15. Determining Specific Window Period for Common Scab Disease Infection in Potato Tubers

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    Bhim Bahadur Khatri

    2017-05-01

    Full Text Available A series of experiments was conducted under glasshouse and hydroponic conditions to determine the specific window period for common scab disease infection in potato tubers. The study was performed in a glasshouse system where separate tubers from the root zone were inoculated at different intervals during plant growth along with a novel hydroponic system to inoculate individual tubers at specific times of development growth allowing non-destructive observations of common scab symptoms developing. The window of tuber susceptibility to common scab disease infection was shown to vary with the season or conditions under which the plants were grown. Different internodes on tubers were found susceptible to infection at different times during tuber development. Basal internodes, which are the first sections of the tuber to expand, were susceptible to infection in the beginning of tuber development, whereas apical internodes only became susceptible later in tuber growth when the basal internodes were no longer susceptible.

  16. Potential Role of Carvedilol in the Cardiac Immune Response Induced by Experimental Infection with Trypanosoma cruzi

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    Aline Luciano Horta

    2017-01-01

    Full Text Available Trypanosoma cruzi causes a cardiac infection characterized by an inflammatory imbalance that could become the inciting factor of the illness. To this end, we evaluated the role of carvedilol, a beta-blocker with potential immunomodulatory properties, on the immune response in C57BL/6 mice infected with VL-10 strain of T. cruzi in the acute phase. Animals (n=40 were grouped: (i not infected, (ii infected, (iii infected + carvedilol, and (iv not infected + carvedilol. We analyzed parameters related to parasitemia, plasma levels of TNF, IL-10, and CCL2, and cardiac histopathology after the administration of carvedilol for 30 days. We did not observe differences in the maximum peaks of parasitemia in the day of their detection among the groups. The plasma TNF was elevated at 60 days of infection in mice treated or not with carvedilol. However, we observed a decreased CCL2 level and increased IL-10 levels in those infected animals treated with carvedilol, which impacted the reduction of the inflammatory infiltration in cardiac tissue. For this experimental model, carvedilol therapy was not able to alter the levels of circulating parasites but modulates the pattern of CCL2 and IL-10 mediators when the VL10 strain of T. cruzi was used in C57BL6 mice.

  17. Experimental infection of plants with an herbivore-associated bacterial endosymbiont influences herbivore host selection behavior.

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    Thomas Seth Davis

    Full Text Available Although bacterial endosymbioses are common among phloeophagous herbivores, little is known regarding the effects of symbionts on herbivore host selection and population dynamics. We tested the hypothesis that plant selection and reproductive performance by a phloem-feeding herbivore (potato psyllid, Bactericera cockerelli is mediated by infection of plants with a bacterial endosymbiont. We controlled for the effects of herbivory and endosymbiont infection by exposing potato plants (Solanum tuberosum to psyllids infected with "Candidatus Liberibacter solanacearum" or to uninfected psyllids. We used these treatments as a basis to experimentally test plant volatile emissions, herbivore settling and oviposition preferences, and herbivore population growth. Three important findings emerged: (1 plant volatile profiles differed with respect to both herbivory and herbivory plus endosymbiont infection when compared to undamaged control plants; (2 herbivores initially settled on plants exposed to endosymbiont-infected psyllids but later defected and oviposited primarily on plants exposed only to uninfected psyllids; and (3 plant infection status had little effect on herbivore reproduction, though plant flowering was associated with a 39% reduction in herbivore density on average. Our experiments support the hypothesis that plant infection with endosymbionts alters plant volatile profiles, and infected plants initially recruited herbivores but later repelled them. Also, our findings suggest that the endosymbiont may not place negative selection pressure on its host herbivore in this system, but plant flowering phenology appears correlated with psyllid population performance.

  18. Horses experimentally infected with Sarcocystis neurona develop altered immune responses in vitro.

    Science.gov (United States)

    Witonsky, Sharon G; Ellison, Siobhan; Yang, Jibing; Gogal, Robert M; Lawler, Heather; Suzuki, Yasuhiro; Sriranganathan, Namalwar; Andrews, Frank; Ward, Daniel; Lindsay, David S

    2008-10-01

    Equine protozoal myeloencephalitis (EPM) due to Sarcocystis neurona infection is 1 of the most common neurologic diseases in horses in the United States. The mechanisms by which most horses resist disease, as well as the possible mechanisms by which the immune system may be suppressed in horses that develop EPM, are not known. Therefore, the objectives of this study were to determine whether horses experimentally infected with S. neurona developed suppressed immune responses. Thirteen horses that were negative for S. neurona antibodies in serum and cerebrospinal fluid (CSF) were randomly assigned to control (n = 5) or infected (n = 8) treatment groups. Neurologic exams and cerebrospinal fluid analyses were performed prior to, and following, S. neurona infection. Prior to, and at multiple time points following infection, immune parameters were determined. All 8 S. neurona-infected horses developed clinical signs consistent with EPM, and had S. neurona antibodies in the serum and CSF. Both infected and control horses had increased percentages (P < 0.05) of B cells at 28 days postinfection. Infected horses had significantly decreased (P < 0.05) proliferation responses as measured by thymidine incorporation to nonspecific mitogens phorbol myristate acetate (PMA) and ionomycin (I) as soon as 2 days postinfection.

  19. Temporal dynamics of 'HoBi'-like pestivirus quasispecies in persistently infected calves generated under experimental conditions.

    Science.gov (United States)

    Weber, Matheus N; Bauermann, Fernando V; Canal, Cláudio W; Bayles, Darrell O; Neill, John D; Ridpath, Julia F

    2017-01-02

    'HoBi'-like virus is an atypical group within the Pestivirus genus that is implicated in economic losses for cattle producers due to both acute and persistent infections. Pestivirus strains exist as quasispecies (swarms of individual viruses) in infected animals and the viral populations making up the quasispecies differ widely in size and diversity in each animal. In the present study the viral quasispecies circulating in persistently infected (PI) calves, generated and maintained under experimental conditions using two different 'HoBi'-like strains, was observed over time. An increase in genetic variability and the development of certain mutations was observed over time. Mutations observed included the loss of a putative N-linked glycosylation site in the E2 region and the change of specific residues in E1/E2. It is hypothesized that these changes may be the results on continued adaption of the pestivirus to individual hosts. This is the first study characterizing variation in the viral swarms of animals persistently infected with HoBi-like viruses over time. Studies of the shifts in PI viral swarms will contribute to our understanding of the host and viral mechanisms that function in the maintenance of pestivirus persistent infections. Published by Elsevier B.V.

  20. Dynamics of a Fractional Order HIV Infection Model with Specific Functional Response and Cure Rate

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    Adnane Boukhouima

    2017-01-01

    Full Text Available We propose a fractional order model in this paper to describe the dynamics of human immunodeficiency virus (HIV infection. In the model, the infection transmission process is modeled by a specific functional response. First, we show that the model is mathematically and biologically well posed. Second, the local and global stabilities of the equilibria are investigated. Finally, some numerical simulations are presented in order to illustrate our theoretical results.

  1. Molecularly specific detection of bacterial lipoteichoic acid for diagnosis of prosthetic joint infection of the bone.

    Science.gov (United States)

    Pickett, Julie E; Thompson, John M; Sadowska, Agnieszka; Tkaczyk, Christine; Sellman, Bret R; Minola, Andrea; Corti, Davide; Lanzavecchia, Antonio; Miller, Lloyd S; Thorek, Daniel Lj

    2018-01-01

    Discriminating sterile inflammation from infection, especially in cases of aseptic loosening versus an actual prosthetic joint infection, is challenging and has significant treatment implications. Our goal was to evaluate a novel human monoclonal antibody (mAb) probe directed against the Gram-positive bacterial surface molecule lipoteichoic acid (LTA). Specificity and affinity were assessed in vitro. We then radiolabeled the anti-LTA mAb and evaluated its effectiveness as a diagnostic imaging tool for detecting infection via immunoPET imaging in an in vivo mouse model of prosthetic joint infection (PJI). In vitro and ex vivo binding of the anti-LTA mAb to pathogenic bacteria was measured with Octet, ELISA, and flow cytometry. The in vivo PJI mouse model was assessed using traditional imaging modalities, including positron emission tomography (PET) with [ 18 F]FDG and [ 18 F]NaF as well as X-ray computed tomography (CT), before being evaluated with the zirconium-89-labeled antibody specific for LTA ([ 89 Zr]SAC55). The anti-LTA mAb exhibited specific binding in vitro to LTA-expressing bacteria. Results from imaging showed that our model could reliably simulate infection at the surgical site by bioluminescent imaging, conventional PET tracer imaging, and bone morphological changes by CT. One day following injection of both the radiolabeled anti-LTA and isotype control antibodies, the anti-LTA antibody demonstrated significantly greater ( P  infected prosthesis sites over either the same antibody at sterile prosthesis sites or of control non-specific antibody at infected prosthesis sites. Taken together, the radiolabeled anti-LTA mAb, [ 89 Zr]SAC55, may serve as a valuable diagnostic molecular imaging probe to help distinguish between sterile inflammation and infection in the setting of PJI. Future studies are needed to determine whether these findings will translate to human PJI.

  2. The pathogenesis of single experimental infections with Strongylus vulgaris in foals.

    Science.gov (United States)

    Duncan, J L; Pirie, H M

    1975-01-01

    The clinical signs, pathology and clinical pathology associated with single experimental infections of Strongylus vulgaris in worm-free pony foals are described. The major clinical signs which became apparent in the infected foals during the first three weeks were pyrexia, anorexia, dullness and abdominal pain. Within the first two weeks of infection lesions were confined to the intestine and terminal branches of the intestinal arteries and consisted of mucosal, submucosal and serosal haemorrhage together with arteritis of submucosal and serosal arteries and also a marked inflammatory reaction. The main lesion seen three weeks after infection was gross thrombosis of the anterior mesenteric artery or one of its major branches. On section these affected arteries showed marked intimal thickening with infiltration of plasma cells, lymphocytes, macrophages and neutrophils. Between one and four months after infection the gross lesions were predominantly in the arteries and consisted of fibrous thickening of the arterial wall and thrombosis associated with the presence of developing fourth stage larvae. Four months after infection the arterial lesions were still prominent and microscopically there was fibrosis of the wall of the affected artery with wide-spread disruption of the intima. In the adventitia organised thrombi were apparent in the vasa vasorum and resulted in the obliteration of their lumina. The typical lesion associated with the return of fifth stage larvae to the intestine was nodule formation in close proximity to thrombosed terminal intestinal arteries and sections of parasites were seen in the intestinal wall surrounded by neutrophils and necrotic debris. By nine months after infection the arterial lesion had healed, but histologically there was fibrosis of the intima and macrophages containing haemosiderin were seen in the arterial wall. The most significant haematological findings during the experimental period were a marked polymorphonuclear

  3. Immunologic responses in corn snakes (Pantherophis guttatus) after experimentally induced infection with ferlaviruses.

    Science.gov (United States)

    Neul, Annkatrin; Schrödl, Wieland; Marschang, Rachel E; Bjick, Tina; Truyen, Uwe; von Buttlar, Heiner; Pees, Michael

    2017-04-01

    OBJECTIVE To measure immunologic responses of snakes after experimentally induced infection with ferlaviruses. ANIMALS 42 adult corn snakes (Pantherophis guttatus) of both sexes. PROCEDURES Snakes were inoculated intratracheally with genogroup A (n = 12), B (12), or C (12) ferlavirus (infected groups) or cell-culture supernatant (6; control group) on day 0. Three snakes from each infected group were euthanized on days 4, 16, 28, and 49, and 3 snakes from the control group were euthanized on day 49. Blood samples were collected from live snakes on days -6 (baseline), 4, 16, 28, and 49. Hematologic tests were performed and humoral responses assessed via hemagglutination-inhibition assays and ELISAs. Following euthanasia, gross pathological and histologic evaluations and virus detection were performed. RESULTS Severity of clinical signs of and immunologic responses to ferlavirus infection differed among snake groups. Hematologic values, particularly WBC and monocyte counts, increased between days 4 and 16 after infection. A humoral response was identified between days 16 and 28. Serum IgM concentrations increased from baseline earlier than IgY concentrations, but the IgY relative increase was higher at the end of the study. The hemagglutination-inhibition assay revealed that the strongest reactions in all infected groups were against the strain with which they had been infected. Snakes infected with genogroup A ferlavirus had the strongest immune response, whereas those infected with genogroup B had the weakest responses. CONCLUSIONS AND CLINICAL RELEVANCE Results of this experimental study suggested that the ferlavirus strain with the highest virulence induced the weakest immune response in snakes.

  4. Humoral immune responses of experimentally Eimeria ninakholyakimovae-infected goat kids.

    Science.gov (United States)

    Matos, Lorena; Muñoz, María Del Carmen; Molina, José Manuel; Ferrer, Otilia; Rodríguez, Francisco; Pérez, Davinia; López, Adassa María; Martín, Sergio; Hermosilla, Carlos; Taubert, Anja; Ruiz, Antonio

    2017-04-01

    Although cellular immune reactions seem to be crucial for protective immune responses in Eimeria spp. infections, there are also evidences on an active involvement of the humoral counterpart. In the present study, we have analyzed the humoral response of goat kids subjected to primary and challenge infections with Eimeria ninakholyakimovae. Specific levels of IgG and IgM in serum samples and IgA in the ileal mucus were estimated. In infected kids, significantly increased levels of IgG were observed from 3 weeks post infection onwards in addition to an enhancement of specific IgM and secretory IgA levels. A wide range of peptides of sporulated oocyst antigen (SOA) was recognized by specific IgG as determined by immunoblotting. However, no correlations were found between immunoglobulin levels and OPG counts after challenge infection. Overall, these data indicate a significant specific humoral response of E. ninakohlyakimovae-infected goat kids that does not seem to convey immunoprotection. Further studies should be addressed to clarify if the lack of correlation might be associated to the type of antigen used for the immunoenzimatic assays, the age of the animals or other factors. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Experimental and natural infections in MyD88- and IRAK-4-deficient mice and humans

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    von Bernuth, Horst; Picard, Capucine; Puel, Anne; Casanova, Jean-Laurent

    2013-01-01

    Most Toll-like-receptors (TLRs) and interleukin-1 receptors (IL-1Rs) signal via myeloid differentiation primary response 88 (MyD88) and interleukin-1 receptor-associated kinase 4 (IRAK-4). The combined roles of these two receptor families in the course of experimental infections have been assessed in MyD88- and IRAK-4-deficient mice for almost fifteen years. These animals have been shown to be susceptible to 46 pathogens: 27 bacteria, 8 viruses, 7 parasites, and 4 fungi. Humans with inborn MyD88 or IRAK-4 deficiency were first identified in 2003. They suffer from naturally occurring life-threatening infections caused by a small number of bacterial species, although the incidence and severity of these infections decrease with age. Mouse TLR- and IL-1R-dependent immunity mediated by MyD88 and IRAK-4 seems to be vital to combat a wide array of experimentally administered pathogens at most ages. By contrast, human TLR- and IL-1R-dependent immunity mediated by MyD88 and IRAK-4 seems to be effective in the natural setting against only a few bacteria and is most important in infancy and early childhood. The roles of TLRs and IL-1Rs in protective immunity deduced from studies in mutant mice subjected to experimental infections should therefore be reconsidered in the light of findings for natural infections in humans carrying mutations as discussed in this review. PMID:23255009

  6. Suppression of inflammatory immune responses in celiac disease by experimental hookworm infection.

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    Henry J McSorley

    Full Text Available We present immunological data from two clinical trials where the effect of experimental human hookworm (Necator americanus infection on the pathology of celiac disease was evaluated. We found that basal production of Interferon- (IFN-γ and Interleukin- (IL-17A from duodenal biopsy culture was suppressed in hookworm-infected participants compared to uninfected controls. Increased levels of CD4+CD25+Foxp3+ cells in the circulation and mucosa are associated with active celiac disease. We show that this accumulation also occurs during a short-term (1 week oral gluten challenge, and that hookworm infection suppressed the increase of circulating CD4+CD25+Foxp3+ cells during this challenge period. When duodenal biopsies from hookworm-infected participants were restimulated with the immunodominant gliadin peptide QE65, robust production of IL-2, IFN-γ and IL-17A was detected, even prior to gluten challenge while participants were strictly adhering to a gluten-free diet. Intriguingly, IL-5 was produced only after hookworm infection in response to QE65. Thus we hypothesise that hookworm-induced TH2 and IL-10 cross-regulation of the TH1/TH17 inflammatory response may be responsible for the suppression of these responses during experimental hookworm infection.

  7. Experimental infection of Artibeus intermedius with a vampire bat rabies virus.

    Science.gov (United States)

    Obregón-Morales, Cirani; Aguilar-Setién, Álvaro; Perea Martínez, Leonardo; Galvez-Romero, Guillermo; Martínez-Martínez, Flor Olivia; Aréchiga-Ceballos, Nidia

    2017-06-01

    Experimental infection of Artibeus intermedius, the great fruit-eating bat, was performed with vampire bat rabies isolates. Bats (n=35) were captured in the wild and quarantined prior to experimental infection. No rabies antibodies were detected by rapid fluorescent focus inhibition test (RFFIT) prior to infection. Three doses of rabies virus (RV) and three different routes of infection were used. One out of 35 bats died without showing any clinical signs at day 14 and was positive for rabies. None of the 34 other bats showed clinical signs for rabies, but high antibody titers were detected post-inoculation, suggesting either innate immune response to the vampire bat rabies virus or possible pre-exposure to RV and inoculation leading to a booster effect. Rabies virus was detected by hemi-nested RT-PCR (hnRT-PCR) in the brain (n=3), stomach (n=1) of bats that were negative by immunofluorescence and that survived rabies infection. The bat that died on day 14 was positive by hnRT-PCR on the brain, heart and liver. These results suggest that either previous non-lethal exposure to RV or natural low susceptibility to vampire bat viruses somehow protected Artibeus intermedius from clinical rabies infection leading to a marginal lethality effect on this bats species population in the wild. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Experimental Infection of Taenia saginata eggs in Bali Cattle: Distribution and Density of Cysticercus bovis

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    Nyoman Sadra Dharmawan

    2009-12-01

    Full Text Available The objective of this study was to observe the development, distribution, and infection density ofTaenia saginata metacestodes in Bali cattle. Three Bali cattle were experimentally infected with T. saginataeggs which were collected from taeniasis patients. The experimental animal was inoculated with : i1000,00 T. saginata; ii 500,000 eggs; and iii 1,000,000 eggs, respectivelly 100,000 (cattle 1, 500,000(cattle 2, and 1,000,000 (cattle 3 T. saginata eggs, respectively. To observe the development of cysticerci,all cattle were slaughtered at 24 weeks post infection. To observe their distribution and density, slicingwas done to the cattle?s tissues. The study results showed that cysts were found distributed to all muscletissues and some visceral organs such as heart, diaphragm, lungs, and kidney of the cattle infected with100,000 and 500,000 T. saginata eggs. Density of the cyst was in the range of 11 to 95 cysts per 100 gramsof tissue. The highest density was noted in the heart (58/100 grams and in diaphragm (55/100 grams.This study has confirmed that T. saginata eggs derived from taeniasis patient in Bali, if infected to Balicattle can develop and spread to all muscle tissues and some visceral organs. From this study it wasconcluded that it is necessary to include the heart in the meat inspection at slaughter house for possibilityof T. saginata cyst infection.$?

  9. Pathogenesis and immune response in Atlantic salmon (Salmo salar L.) parr experimentally infected with salmon pancreas disease virus (SPDV).

    Science.gov (United States)

    Desvignes, L; Quentel, C; Lamour, F; le, Ven A

    2002-01-01

    Atlantic salmon parr were injected intraperitoneally with salmon pancreas disease virus (SPDV) grown on CHSE-214 cells. The viraemia, the histopathological changes in target organs and some immune parameters were taken at intervals up to 30 days post-infection (dpi). The earliest kind of lesion was necrosis of exocrine pancreas, appearing as soon as 2 dpi. It progressed towards complete tissue breakdown at 9 dpi before resolving gradually. Concurrent to this necrosis, a strong inflammatory response was in evidence from 9 dpi in the pancreatic area for a majority of fish. A necrosis of the myocardial cells of the ventricle occurred in infected fish mainly at 16 dpi and it faded thereafter. The monitoring of the plasma viral load showed a rapid haematogenous spreading of SPDV, peaking at 4 dpi, but also the absence of a secondary viraemia. No interferon (IFN) was detected following the infection of parr with SPDV, probably owing to an IFN activity in Atlantic salmon below the detection level of the technique. Neutralising antibodies against SPDV were in evidence from 16 dpi and they showed a time-related increasing titre and prevalence. The phagocytic activity in head-kidney leucocytes was always significantly higher in the infected fish than in the control fish, being particularly high by 9 dpi. Lysozyme and complement levels were both increased and they peaked significantly in the infected fish at 9 and 16 dpi respectively. These results demonstrated that an experimental infection of Atlantic salmon parr with SPDV provoked a stimulation of both specific and non-specific immunity with regards to the viraemia and the histopathology.

  10. Fibrinogen and fibronectin binding cooperate for valve infection and invasion in Staphylococcus aureus experimental endocarditis

    NARCIS (Netherlands)

    Que, Yok-Ai; Haefliger, Jacques-Antoine; Piroth, Lionel; François, Patrice; Widmer, Eleonora; Entenza, José M; Sinha, Bhanu; Herrmann, Mathias; Francioli, Patrick; Vaudaux, Pierre; Moreillon, Philippe

    2005-01-01

    The expression of Staphylococcus aureus adhesins in Lactococcus lactis identified clumping factor A (ClfA) and fibronectin-binding protein A (FnBPA) as critical for valve colonization in rats with experimental endocarditis. This study further analyzed their role in disease evolution. Infected

  11. Detection of Toxoplasma gondii DNA in sera samples of mice experimentally infected

    Directory of Open Access Journals (Sweden)

    H. Langoni

    2006-04-01

    Full Text Available Detection of Toxoplasma gondii (T. gondii DNA in blood can help to diagnose the disease in its acute phase; however, it must be considered that hemoglobin, present in blood, can inhibit polymerase activity, making impracticable the detection of DNA in samples. Mice were experimentally infected via oral route with ME49 and BTU2 strains cysts and RH strain tachyzoites; polymerase chain reaction was used to detect T. gondii DNA in mice sera 18, 24, 48, 96, and 192 hours post infection (PI. Toxoplama gondii DNA was detected in only one animal infected with BTU2 strain, genotype III (isolated from a dog with neurological signs 18 hours PI. The agent's DNA was not detected in any sample of the other experimental groups. New studies must be carried out to verify the technique sensitivity in researches on this agent's genetic material using sera samples of acute-phase toxoplasmosis patients, especially in cases of immunosuppression.

  12. Experimental Maedi Visna Virus Infection in sheep: a morphological, immunohistochemical and PCR study after three years of infection

    Directory of Open Access Journals (Sweden)

    S Preziuso

    2009-06-01

    Full Text Available A morphological, immunohistochemical and polymerase chain reaction (PCR study was performed on eight ewes experimentally infected with an Italian strain of Maedi-Visna Virus (MVV in order to evaluate the lesions and the viral distribution after three years of infection. At the moment of euthanasia, seven sheep were seropositive for MVV, while one sheep in poor body conditions was seronegative since one year. Lungs, pulmonary lymph nodes, udder, supramammary lymph nodes, carpal joints, the CNS, spleen and bone marrow of the eight infected sheep were collected for histology, for immunohistochemical detection of the MVV core protein p28 and for PCR amplification of a 218 bp viral DNA sequence of the pol region. The most common histological findings consisted of interstitial lymphoproliferative pneumonia and lymphoproliferative mastitis of different severity, while no lesions were observed in the CNS. MVV p28 antigen was immunohistochemically labelled in lungs, udder, pulmonary lymph nodes, spleen and bone marrow but not in the CNS of all the eight infected sheep. A 218 bp sequence of MVV pol region was detected in lung of a seropositive and of the seroconverted negative sheep. The results suggest that (i MVV causes heterogeneous lesions in homogeneously reared ewes, (ii MVV p28 antigen is detectable not only in inflammed target organs, but also in pulmonary lymph nodes, spleen and bone marrow, and (iii immunohistochemistry and PCR are useful methods for Maedi-Visna diagnosis in suspected cases, also when serological tests are negative.

  13. Prolonged activation of virus-specific CD8+T cells after acute B19 infection

    DEFF Research Database (Denmark)

    Isa, Adiba; Kasprowicz, Victoria; Norbeck, Oscar

    2005-01-01

    BACKGROUND: Human parvovirus B19 (B19) is a ubiquitous and clinically significant pathogen, causing erythema infectiosum, arthropathy, transient aplastic crisis, and intrauterine fetal death. The phenotype of CD8+ T cells in acute B19 infection has not been studied previously. METHODS AND FINDINGS......: The number and phenotype of B19-specific CD8+ T cell responses during and after acute adult infection was studied using HLA-peptide multimeric complexes. Surprisingly, these responses increased in magnitude over the first year post-infection despite resolution of clinical symptoms and control of viraemia......, with T cell populations specific for individual epitopes comprising up to 4% of CD8+ T cells. B19-specific T cells developed and maintained an activated CD38+ phenotype, with strong expression of perforin and CD57 and downregulation of CD28 and CD27. These cells possessed strong effector function...

  14. Experimental infection with the small intestinal trematode, Haplorchis pumilio, in young dogs

    DEFF Research Database (Denmark)

    Nissen, Sofie; Nguyen, Lan Anh Thi; Dalsgaard, Anders

    2013-01-01

    included as uninfected controls. Faecal examination for eggs was performed twice weekly using a sieving and sedimentation technique. Body temperature and weight of the dogs were measured as was total white blood cells, blood eosinophils and packed cell volume. Subsets of dogs were examined post......Fishborne zoonotic trematodes (FZT) are highly prevalent in Southeast Asia. Recent studies on the role of domestic animals in the transmission of FZT in Northern Vietnam found that dogs, mainly infected with Haplorchis pumilio, contributed widely to the transmission of FZT. On this background, we...... conducted an experimental infection with H. pumilio to elucidate population dynamics and host reactions in dogs. Eight household-reared dogs (3-6 months old), were each orally infected with 500 H. pumilio metacercariae obtained by artificial digestion of naturally infected fish. Another eight dogs were...

  15. Destructive arthritis in a patient with chikungunya virus infection with persistent specific IgM antibodies

    Directory of Open Access Journals (Sweden)

    Receveur Marie-Catherine

    2009-12-01

    Full Text Available Abstract Background Chikungunya fever is an emerging arboviral disease characterized by an algo-eruptive syndrome, inflammatory polyarthralgias, or tenosynovitis that can last for months to years. Up to now, the pathophysiology of the chronic stage is poorly understood. Case presentation We report the first case of CHIKV infection with chronic associated rheumatism in a patient who developed progressive erosive arthritis with expression of inflammatory mediators and persistence of specific IgM antibodies over 24 months following infection. Conclusions Understanding the specific features of chikungunya virus as well as how the virus interacts with its host are essential for the prevention, treatment or cure of chikungunya disease.

  16. Infectivity of DWV associated to flower pollen: experimental evidence of a horizontal transmission route.

    Directory of Open Access Journals (Sweden)

    Maurizio Mazzei

    Full Text Available Deformed wing virus (DWV is a honeybee pathogen whose presence is generally associated with infestation of the colony by the mite Varroa destructor, leading to the onset of infections responsible for the collapse of the bee colony. DWV contaminates bee products such as royal jelly, bee-bread and honey stored within the infected hive. Outside the hive, DWV has been found in pollen loads collected directly from infected as well as uninfected forager bees. It has been shown that the introduction of virus-contaminated pollen into a DWV-free hive results in the production of virus-contaminated food, whose role in the development of infected bees from virus-free eggs has been experimentally demonstrated. The aim of this study was twofold: (i to ascertain the presence of DWV on pollen collected directly from flowers visited by honeybees and then quantify the viral load and (ii determine whether the virus associated with pollen is infective. The results of our investigation provide evidence that DWV is present on pollen sampled directly from visited flowers and that, following injection in individuals belonging to the pollinator species Apis mellifera, it is able to establish an active infection, as indicated by the presence of replicating virus in the head of the injected bees. We also provide the first indication that the pollinator species Osmia cornuta is susceptible to DWV infection.

  17. Distribution of sialic acid receptors and influenza A viruses of avian and swine origin and in experimentally infected pigs

    DEFF Research Database (Denmark)

    Trebbien, Ramona; Larsen, Lars Erik; Viuff, Birgitte M.

    2011-01-01

    Background: Pigs are considered susceptible to influenza A virus infections from different host origins because earlier studies have shown that they have receptors for both avian (sialic acid-alpha-2,3-terminal saccharides (SAalpha- 2,3)) and swine/human (SA-alpha-2,6) influenza viruses...... in the upper respiratory tract. Furthermore, experimental and natural infections in pigs have been reported with influenza A virus from avian and human sources. Methods: This study investigated the receptor distribution in the entire respiratory tract of pigs using specific lectins Maackia Amurensis (MAA) I...... and AIV virus was found, and this difference was in accordance with the distribution of the SA-alpha-2,6 and SA-alpha-2,3 receptor, respectively. The results indicated that the distribution of influenza A virus receptors in pigs are similar to that of humans and therefore challenge the theory that the pig...

  18. Assessment of PCR in the detection of Leishmania spp in experimentally infected individual phlebotomine sandflies (Diptera: Psychodidae: Phlebotominae

    Directory of Open Access Journals (Sweden)

    MICHALSKY Érika M.

    2002-01-01

    Full Text Available DNA amplification by the polymerase chain reaction (PCR was applied in the investigation of the presence of Leishmania (Kinetoplastida: Trypanosomatidae parasites in single phlebotomine sandflies. Three phlebotomine/parasite pairs were used: Lutzomyia longipalpis/Leishmania chagasi, Lutzomyia migonei/Leishmania amazonensis and Lutzomyia migonei/Leishmania braziliensis, all of them incriminated in the transmission of visceral or cutaneous leishmaniasis. DNA extraction was performed with whole insects, with no need of previous digestive tract dissection or pooling specimens. The presence of either mouse blood in the digestive tract of the sandflies or the digestive tract itself did not interfere in the PCR. Infection by as few as 10 Leishmania sp. per individual were sufficient for DNA amplification with genus-specific primers. Using primers for L. braziliensis and L. mexicana complexes, respectively, it was possible to discriminate between L. braziliensis and L. amazonensis in experimentally infected vectors (L. migonei.

  19. Experimental test of host specificity in a behaviour-modifying trematode

    DEFF Research Database (Denmark)

    Hernandez, R.N.; Fredensborg, Brian Lund

    2015-01-01

    Host behavioural modification by parasites is a common and well-documented phenomenon. However, knowledge on the complexity and specificity of the underlying mechanisms is limited, and host specificity among manipulating parasites has rarely been experimentally verified. We tested the hypothesis...

  20. Dietary cinnamaldehyde enhances acquisition of specific antibodies following helminth infection in pigs

    DEFF Research Database (Denmark)

    Williams, Andrew R.; Hansen, Tina V. A.; Krych, Lukasz

    2017-01-01

    immune responses during infection with an enteric pathogen. We examined the effect of dietary CA on plasma antibody levels in parasite-naïve pigs, and subsequently acquisition of humoral immune responses during infection with the parasitic nematode Ascaris suum. Parasite-naïve pigs fed diets supplemented...... with CA had higher levels of total IgA and IgG in plasma, and A. suum-infected pigs fed CA had higher levels of parasite-specific IgM and IgA in plasma 14days post-infection. Moreover, dietary CA increased expression of genes encoding the B-cell marker CD19, sodium/glucose co-transporter1 (SCA5L1...

  1. Efficacy of imidocarb dipropionate in eliminating Theileria equi from experimentally infected horses.

    Science.gov (United States)

    Grause, Juanita F; Ueti, Massaro W; Nelson, Jeffrey T; Knowles, Donald P; Kappmeyer, Lowell S; Bunn, Thomas O

    2013-06-01

    Theileria equi, one of the causative agents of equine piroplasmosis, is endemic in many regions of the world but is considered a 'foreign' animal disease in the USA. In an effort to prevent the importation of T. equi, stringent serological screening of horses is practiced prior to entry to the USA. Current regulatory options available where horses are found to be infected include permanent quarantine with or without chemotherapy, repatriation, or euthanasia. Chemotherapeutics that eliminate infection and subsequently transmission risk are critical in the management of infected horses. In this study, the efficacy of the drug imidocarb dipropionate against experimental T. equi infection was assessed. Of nine horses experimentally inoculated with T. equi isolated from an animal previously imported from Peru, six were treated with imidocarb dipropionate after the resolution of the acute phase of the disease. Elimination of the parasite was demonstrated in 5/6 by nested PCR, blood transfusions to naïve horses, and reversion to seronegative status. The findings support the use of this drug as a potential treatment option in controlling outbreaks of T. equi, and also suggest that 'combination testing' using both serological and PCR detection methods are necessary to demonstrate clearance of infection. Published by Elsevier Ltd.

  2. Imaging experimental infective endocarditis with indium-111-labeled blood cellular components

    International Nuclear Information System (INIS)

    Riba, A.L.; Thakur, M.L.; Gottschalk, A.; Andriole, V.T.; Zaret, B.L.

    1979-01-01

    The capability of radionuclide imaging to detect experimental aortic valve infective endocarditis was assessed with indium-111 ( 111 In)-labeled blood cells. Sequential cardiac imaging and tissue distribution studies were obtained in 17 rabbits with infective endocarditis after administration of 111 In-platelets and in five after 111 In-polymorphonuclear leukocytes. Forty-eight to 72 hours after platelet administration, in vivo imaging demonstrated abnormal 111 In uptake in all animals in the region of the aortic valve in an anatomically distinct pattern. Images of the excised heart showed discrete cardiac uptake conforming to the in vivo image and gross pathological examination. 111 In-platelet uptake in vegetations from the 17 animals averaged 240 +- 41 times greater than that in normal myocardium and 99 +- 15 times greater uptake in blood. In contrast, 111 In-leukocyte cardiac imaging showed no abnormal aortic valve uptake 24 hours after tracer administration and the lesion myocardium activity ratio was only 5 +- 2 (3 +- 1 for lesion/blood activity). Four normal rabbits demonstrated neither positive 111 In-platelet scintigraphs nor abnormal cardiac tissue uptake. Likewise, noncellular 111 In was not concentrated to any significant extent in three animals with infective endocarditis. This study demonstrates that 111 In-platelet, but not leukocyte cardiac imaging, is a sensitive technique for detecting experimental infective endocarditis. The imaging data conform to the cellular pathology of the infective endocarditis vegetation

  3. Metabolomic profiling of faecal extracts from Cryptosporidium parvum infection in experimental mouse models.

    Directory of Open Access Journals (Sweden)

    Josephine S Y Ng Hublin

    Full Text Available Cryptosporidiosis is a gastrointestinal disease in humans and animals caused by infection with the protozoan parasite Cryptosporidium. In healthy individuals, the disease manifests mainly as acute self-limiting diarrhoea, but may be chronic and life threatening for those with compromised immune systems. Control and treatment of the disease is challenged by the lack of sensitive diagnostic tools and broad-spectrum chemotherapy. Metabolomics, or metabolite profiling, is an emerging field of study, which enables characterisation of the end products of regulatory processes in a biological system. Analysis of changes in metabolite patterns reflects changes in biochemical regulation, production and control, and may contribute to understanding the effects of Cryptosporidium infection in the host environment. In the present study, metabolomic analysis of faecal samples from experimentally infected mice was carried out to assess metabolite profiles pertaining to the infection. Gas-chromatography mass spectrometry (GC-MS carried out on faecal samples from a group of C. parvum infected mice and a group of uninfected control mice detected a mean total of 220 compounds. Multivariate analyses showed distinct differences between the profiles of C. parvum infected mice and uninfected control mice,identifying a total of 40 compounds, or metabolites that contributed most to the variance between the two groups. These metabolites consisted of amino acids (n = 17, carbohydrates (n = 8, lipids (n = 7, organic acids (n = 3 and other various metabolites (n = 5, which showed significant differences in levels of metabolite abundance between the infected and uninfected mice groups (p < 0.05. The metabolites detected in this study as well as the differences in abundance between the C. parvum infected and the uninfected control mice, highlights the effects of the infection on intestinal permeability and the fate of the metabolites as a result of nutrient scavenging by the

  4. Pathogenesis of canine distemper virus in experimentally infected raccoon dogs, foxes, and minks.

    Science.gov (United States)

    Zhao, Jianjun; Shi, Ning; Sun, Yangang; Martella, Vito; Nikolin, Veljko; Zhu, Chunsheng; Zhang, Hailing; Hu, Bo; Bai, Xue; Yan, Xijun

    2015-10-01

    Canine distemper virus (CDV) infects a broad range of carnivores and causes a highly contagious disease with severe immunosuppression. The disease severity markedly varies in different species. To investigate the pathogenesis of CDV in raccoon dog (Nyctereutes procyonoides), fox (Vulpes vulpes) and mink (Neovison vison) species, three groups of CDV sero-negative animals were infected with CDV strain LN(10)1. This CDV strain belongs to the Asia-1 genotype, which is epidemiologically predominant in carnivores in China. CDV infection provoked marked differences in virulence in the three species that were studied. Raccoon dogs developed fever, severe conjunctivitis, and pathological lesions, with 100% (5/5) mortality and with high viral RNA loads in organs within 15 days post infection (dpi). In infected foxes, the onset of the disease was delayed, with 40% (2/5) mortality by 21 dpi. Infected minks developed only mild clinical signs and pathological lesions, and mortality was not observed. Raccoon dogs and foxes showed more severe immune suppression (lymphopenia, decreased lymphocyte proliferation, viremia and low-level virus neutralizing antibodies) than minks. We also observed a distinct pattern of cytokine mRNA transcripts at different times after infection. Decreased IFN-γ and IL-4 mRNA responses were evident in the animals with fatal disease, while up-regulation of these cytokines was observed in the animals surviving the infection. Increased TNF-α response was detected in animals with mild or severe clinical signs. Based on the results, we could distinguish three different patterns of disease after experimental CDV infection, e.g. a mild form in minks, a moderate form in foxes and a severe disease in raccoon dogs. The observed differences in susceptibility to CDV could be related to distinct host cytokine profiles. Comparative evaluation of CDV pathogenesis in various animal species is pivotal to generate models suitable for the evaluation of CDV

  5. Experimental determination of nanofluid specific heat with SiO2 nanoparticles in different base fluids

    Science.gov (United States)

    Akilu, S.; Baheta, A. T.; Sharma, K. V.; Said, M. A.

    2017-09-01

    Nanostructured ceramic materials have recently attracted attention as promising heat transfer fluid additives owing to their outstanding heat storage capacities. In this paper, experimental measurements of the specific heats of SiO2-Glycerol, SiO2-Ethylene Glycol, and SiO2-Glycerol/Ethylene Glycol mixture 60:40 ratio (by mass) nanofluids with different volume concentrations of 1.0-4.0% have been carried out using differential scanning calorimeter at temperatures of 25 °C and 50 °C. Experimental results indicate lower specific heat capacities are found with SiO2 nanofluids compared to their respective base fluids. The specific heat was decreasing with the increase of concentration, and this decrement depends on upon the type of the base fluid. It is observed that temperature has a positive impact on the specific heat capacity. Furthermore, the experimental values were compared with the theoretical model predictions, and a satisfactory agreement was established.

  6. Aberrant chlamydial developmental forms in the gastrointestinal tract of pigs spontaneously and experimentally infected with Chlamydia suis.

    Science.gov (United States)

    Pospischil, Andreas; Borel, Nicole; Chowdhury, Emdad H; Guscetti, Franco

    2009-03-16

    The phenomenon of persistence is well known from in vitro studies, where it is associated with the production of aberrant bodies, but its occurrence in vivo is less well documented. The objective of this study was to search for aberrant bodies in intestinal tissues from pigs, describe their ultrastructure, and investigate the suitability of immunohistochemical staining for chlamydial heat shock protein 60 (cHSP60) to detect such forms. Intestinal tissues derived from pigs naturally and experimentally infected with Chlamydia (C.) suis were examined by immunohistochemistry, transmission electron microscopy and immunogold electron microscopy. The chlamydial species involved in the natural infection were determined using an Array Tube Microarray to C. suis and Chlamydophila abortus. Ultrastructurally, aberrant bodies were detected in the gut of both naturally and experimentally infected pigs. Immunogold electron microscopy showed that the aberrant bodies were labeled less strongly than the normal forms by antibodies against LPS and cHSP60 respectively. It was concluded that aberrant bodies occur in vivo in pigs and that the gnotobiotic pig model might be suitable for the study of chlamydial persistence in vivo. The antibody against cHSP60 does not appear to be suitable to specifically detect such forms.

  7. Control of mucosal virus infection by influenza nucleoprotein-specific CD8+ cytotoxic T lymphocytes

    Directory of Open Access Journals (Sweden)

    Couch Robert B

    2007-06-01

    Full Text Available Abstract Background MHC class I-restricted CD8+ cytotoxic T lymphocytes (CTL are thought to play a major role in clearing virus and promoting recovery from influenza infection and disease. This has been demonstrated for clearance of influenza virus from the lungs of infected mice. However, human influenza infection is primarily a respiratory mucosal infection involving the nasopharynx and tracheobronchial tree. The role of CD8+ CTL directed toward the influenza nucleoprotein (NP in defense against influenza virus infection at the respiratory mucosa was evaluated in two separate adoptive transfer experiments. Methods Influenza nucleoprotein (NP-specific CD8+ CTL were generated from splenocytes obtained from Balb/c mice previously primed with influenza A/Taiwan/1/86 (H1N1 infection or with influenza A/PR/8/34 (H1N1-derived NP plasmid DNA vaccine followed by infection with A/Hong Kong/68 (H3N2 virus. After in vitro expansion by exposure to an influenza NP-vaccinia recombinant, highly purified CD8+ T cells exhibited significant lysis in vitro of P815 target cells infected with A/Hong Kong/68 (H3N2 virus while the CD8- fraction (CD4+ T cells, B cells and macrophages had no CTL activity. Purified CD8+ and CD8- T cells (1 × 107 were injected intravenously or interperitoneally into naive mice four hours prior to intranasal challenge with A/HK/68 (H3N2 virus. Results The adoptively transferred NP-vaccinia-induced CD8+ T cells caused significant reduction of virus titers in both the lungs and nasal passages when compared to CD8- cells. Neither CD8+ nor CD8- T cells from cultures stimulated with HIV gp120-vaccinia recombinant reduced virus titers. Conclusion The present data demonstrate that influenza NP-specific CD8+ CTL can play a direct role in clearance of influenza virus from the upper respiratory mucosal surfaces.

  8. Phenotypic characterisation of cell populations in the brains of horses experimentally infected with West Nile virus.

    Science.gov (United States)

    Delcambre, G H; Liu, J; Streit, W J; Shaw, G P J; Vallario, K; Herrington, J; Wenzlow, N; Barr, K L; Long, M T

    2017-11-01

    West Nile virus (WNV), a mosquito borne member of the Flaviviridae, is one of the most commonly diagnosed agents of viral encephalitis in horses and people worldwide. A cassette of markers for formalin-fixed paraffin-embedded tissue and an archive of tissues from experimental infections in the horse were used to investigate the equine neuroimmune response to WNV meningoencephalomyelitis to phenotype the early response to WNV infection in the horse. Quantitative analysis using archived tissue from experimentally infected horses. The thalamus and hindbrain from 2 groups of 6 horses were compared and consisted of a culture positive tissues from WNV experimentally horses, in the other, normal horses. Formalin-fixed paraffin-embedded tissue from the thalamus and hindbrain were immunolabeled for microglia, astrocytes, B cells, macrophages/neutrophils, CD3 + T cells. Fresh frozen tissues were immunolabeled for CD4 + and CD8 + T lymphocyte cell markers. Cell counts were obtained using a computer software program. Differences, after meeting assumptions of abnormality, were computed using a general linear model with a Tukey test (Phorses, Iba-1 + microglia, CD3 + T lymphocyte and MAC387 + macrophage staining were significantly increased. The T cell response for the WNV-challenged horses was mixed, composed of CD4 + and CD8 + T lymphocytes. A limited astrocyte response was also observed in WNV-challenged horses, and MAC387 + and B cells were the least abundant cell populations. The results of this study were limited by a single collection time post-infection. Furthermore, a comprehensive analysis of cellular phenotypes is needed for naturally infected horses. Unfortunately, in clinical horses, there is high variability of sampling in terms of days post-infection and tissue handling. The data show that WNV-challenged horses recruit a mixed T cell population at the onset of neurologic disease. © 2017 EVJ Ltd.

  9. Experimental Infection of Snakes with Ophidiomyces ophiodiicola Causes Pathological Changes That Typify Snake Fungal Disease.

    Science.gov (United States)

    Lorch, Jeffrey M; Lankton, Julia; Werner, Katrien; Falendysz, Elizabeth A; McCurley, Kevin; Blehert, David S

    2015-11-17

    Snake fungal disease (SFD) is an emerging skin infection of wild snakes in eastern North America. The fungus Ophidiomyces ophiodiicola is frequently associated with the skin lesions that are characteristic of SFD, but a causal relationship between the fungus and the disease has not been established. We experimentally infected captive-bred corn snakes (Pantherophis guttatus) in the laboratory with pure cultures of O. ophiodiicola. All snakes in the infected group (n = 8) developed gross and microscopic lesions identical to those observed in wild snakes with SFD; snakes in the control group (n = 7) did not develop skin infections. Furthermore, the same strain of O. ophiodiicola used to inoculate snakes was recovered from lesions of all animals in the infected group, but no fungi were isolated from individuals in the control group. Monitoring progression of lesions throughout the experiment captured a range of presentations of SFD that have been described in wild snakes. The host response to the infection included marked recruitment of granulocytes to sites of fungal invasion, increased frequency of molting, and abnormal behaviors, such as anorexia and resting in conspicuous areas of enclosures. While these responses may help snakes to fight infection, they could also impact host fitness and may contribute to mortality in wild snakes with chronic O. ophiodiicola infection. This work provides a basis for understanding the pathogenicity of O. ophiodiicola and the ecology of SFD by using a model system that incorporates a host species that is easy to procure and maintain in the laboratory. Skin infections in snakes, referred to as snake fungal disease (SFD), have been reported with increasing frequency in wild snakes in the eastern United States. While most of these infections are associated with the fungus Ophidiomyces ophiodiicola, there has been no conclusive evidence to implicate this fungus as a primary pathogen. Furthermore, it is not understood why the

  10. Specific T-cell epitopes for immunoassay-based diagnosis of Mycobacterium tuberculosis infection

    DEFF Research Database (Denmark)

    Brock, I; Weldingh, K; Leyten, EM

    2004-01-01

    Specific T-cell epitopes for immunoassay-based diagnosis of Mycobacterium tuberculosis infection.Brock I, Weldingh K, Leyten EM, Arend SM, Ravn P, Andersen P. Department of Infectious Disease Immunology, Statens Serum Institute, Artillerivej 5, DK-2300 Copenhagen S, Denmark. The currently used...... method for immunological detection of tuberculosis infection, the tuberculin skin test, has low specificity. Antigens specific for Mycobacterium tuberculosis to replace purified protein derivative are therefore urgently needed. We have performed a rigorous assessment of the diagnostic potential of four...... recently identified antigens (Rv2653, Rv2654, Rv3873, and Rv3878) from genomic regions that are lacking from the Mycobacterium bovis bacillus Calmette-Guerin (BCG) vaccine strains as well as from the most common nontuberculous mycobacteria. The fine specificity of potential epitopes in these molecules...

  11. Specific T-cell epitopes for immunoassay-based diagnosis of Mycobacterium tuberculosis infection

    DEFF Research Database (Denmark)

    Brock, I; Weldingh, K; Leyten, EM

    2004-01-01

    Specific T-cell epitopes for immunoassay-based diagnosis of Mycobacterium tuberculosis infection.Brock I, Weldingh K, Leyten EM, Arend SM, Ravn P, Andersen P. Department of Infectious Disease Immunology, Statens Serum Institute, Artillerivej 5, DK-2300 Copenhagen S, Denmark. The currently used...... method for immunological detection of tuberculosis infection, the tuberculin skin test, has low specificity. Antigens specific for Mycobacterium tuberculosis to replace purified protein derivative are therefore urgently needed. We have performed a rigorous assessment of the diagnostic potential of four...... selected and combined the specific peptide stretches from the four proteins not recognized by M. bovis BCG-vaccinated individuals. These peptide stretches were tested with peripheral blood mononuclear cells obtained from patients with microscopy- or culture-confirmed tuberculosis and from healthy M. bovis...

  12. Experimental infection of serotine bats (Eptesicus serotinus) with European bat lyssavirus type 1a.

    Science.gov (United States)

    Freuling, C; Vos, A; Johnson, N; Kaipf, I; Denzinger, A; Neubert, L; Mansfield, K; Hicks, D; Nuñez, A; Tordo, N; Rupprecht, C E; Fooks, A R; Müller, T

    2009-10-01

    The serotine bat (Eptesicus serotinus) accounts for the vast majority of bat rabies cases in Europe and is considered the main reservoir for European bat lyssavirus type 1 (EBLV-1, genotype 5). However, so far the disease has not been investigated in its native host under experimental conditions. To assess viral virulence, dissemination and probable means of transmission, captive bats were infected experimentally with an EBLV-1a virus isolated from a naturally infected conspecific from Germany. Twenty-nine wild caught bats were divided into five groups and inoculated by intracranial (i.c.), intramuscular (i.m.) or subcutaneous (s.c.) injection or by intranasal (i.n.) inoculation to mimic the various potential routes of infection. One group of bats was maintained as uninfected controls. Mortality was highest in the i.c.-infected animals, followed by the s.c. and i.m. groups. Incubation periods varied from 7 to 26 days depending on the route of infection. Rabies did not develop in the i.n. group or in the negative-control group. None of the infected bats seroconverted. Viral antigen was detected in more than 50% of the taste buds of an i.c.-infected animal. Shedding of viable virus was measured by virus isolation in cell culture for one bat from the s.c. group at 13 and 14 days post-inoculation, i.e. 7 days before death. In conclusion, it is postulated that s.c. inoculation, in nature caused by bites, may be an efficient way of transmitting EBLV-1 among free-living serotine bats.

  13. Ultrastructural identification of Ehrlich ia sp in an experimentally infected dog in Venezuela

    International Nuclear Information System (INIS)

    Gutierrez, N.; Martinez, M.; Arraga Alvarado, C.; Bretana, A.; Pacheco, I.; Comach, G.

    1999-01-01

    This study is the first report made in Venezuela concerning the ultrastructural characteristics of Ehrlich ia sp in mononuclear blood cells from an experimentally infected dog. The animal developed clinical manifestations characteristic of the infection, and typical intracytoplasmic inclusion bodies were clearly seen in blood smears stained with modified Giemsa examined by light microscopy. Microorganisms were visualized by transmission electron microscopy. The cytoplasmic inclusions, consisted of membrane-lined vacuole-containing elementary bodies. The organisms were extremely pleomorphic. Elementary bodies were surrounded by two distinct membranes and each was constituted by electro-dense granules. These findings corresponded to the described electron microscopy morphology which characterizes the Ehrlich ia genus

  14. Intestinal colonization of broiler chickens by Campylobacter spp. in an experimental infection study

    DEFF Research Database (Denmark)

    Bahrndorff, Simon; Garcia Clavero, Ana Belén; Vigre, Håkan

    2015-01-01

    Consumption of poultry meat is considered as one of the main sources of human campylobacteriosis, and there is clearly a need for new surveillance and control measures based on quantitative data on Campylobacter spp. colonization dynamics in broiler chickens. We conducted four experimental...... infection trials, using four isolators during each infection trial to evaluate colonization of individual broiler chickens by Campylobacter jejuni over time. Individual and pooled faecal samples were obtained at days 4, 7 and 12 post-inoculation (p.i.) and caecal samples at day 12 p.i. There were large...

  15. Cranberry juice and combinations of its organic acids are effective against experimental urinary tract infection

    DEFF Research Database (Denmark)

    Jensen, Heidi Dorthe; Struve, Carsten; Christensen, Søren Brøgger

    2017-01-01

    The antibacterial effect of cranberry juice and the organic acids therein on infection by uro28 pathogenic Escherichia coli was studied in an experimental mouse model of urinary tract infection (UTI). Reduced bacterial counts were found in the bladder (P ... administered singly, did not have any effect in the UTI model. Apparently, the antibacterial effect of the organic acids from cranberry juice on UTI can be obtained by administering a combination of malic acid and either citric or quinic acid. This study show for the first time that cranberry juice reduce E...

  16. Small sarcocysts can be a feature of experimental infections with Sarcocystis neurona merozoites.

    Science.gov (United States)

    Marsh, Antoinette E; Chaney, Sarah B; Howe, Daniel K; Saville, William J; Reed, Stephen M

    2017-10-15

    Several reports indicate the presence of small tissue cysts associated with Sarcocystis neurona infections. Several failed attempts to develop tissue cysts in potential intermediate host using in vitro derived parasites originally isolated from horses with equine protozoal myeloencephalitis suggest that the experimental methods to achieve bradyzoites with those isolates was not possible. Those prior studies reported the lack of detectable sarcocysts based on histology and in vivo feeding trials. A recent report of successful production and detection of small sarcocysts triggered us to review archived tissues from earlier experimental infection studies. The retrospective review sought to determine if small sized sarcocysts were not detected due to their relatively smaller size and infrequency as compared to larger sized sarcocysts produced with other isolates in these experimental inoculation trials. Tissues from two prior in vivo inoculation studies, involving in vitro-produced parasites inoculated into laboratory-reared cats and raccoons, were re-examined by immunohistochemistry staining to more easily detect the tissue cysts. In the experimental cat study no small tissue cysts were seen, consistent with the original publication results. However, in the experimental raccoon study, one raccoon inoculated with an EPM-derived isolate, SN-UCD1, had small sarcocysts not reported in the original publication. This retrospective study suggests that much closer scrutiny of tissues, including the use of immunohistochemistry on tissue sections is required to detect the smaller S. neurona sarcocysts associated with the experimental inoculations of the isolates originally derived from horses with EPM. Published by Elsevier B.V.

  17. Specific and Novel microRNAs Are Regulated as Response to Fungal Infection in Human Dendritic Cells

    Science.gov (United States)

    Dix, Andreas; Czakai, Kristin; Leonhardt, Ines; Schäferhoff, Karin; Bonin, Michael; Guthke, Reinhard; Einsele, Hermann; Kurzai, Oliver; Löffler, Jürgen; Linde, Jörg

    2017-01-01

    Within the last two decades, the incidence of invasive fungal infections has been significantly increased. They are characterized by high mortality rates and are often caused by Candida albicans and Aspergillus fumigatus. The increasing number of infections underlines the necessity for additional anti-fungal therapies, which require extended knowledge of gene regulations during fungal infection. MicroRNAs are regulators of important cellular processes, including the immune response. By analyzing their regulation and impact on target genes, novel therapeutic and diagnostic approaches may be developed. Here, we examine the role of microRNAs in human dendritic cells during fungal infection. Dendritic cells represent the bridge between the innate and the adaptive immune systems. Therefore, analysis of gene regulation of dendritic cells is of particular significance. By applying next-generation sequencing of small RNAs, we quantify microRNA expression in monocyte-derived dendritic cells after 6 and 12 h of infection with C. albicans and A. fumigatus as well as treatment with lipopolysaccharides (LPS). We identified 26 microRNAs that are differentially regulated after infection by the fungi or LPS. Three and five of them are specific for fungal infections after 6 and 12 h, respectively. We further validated interactions of miR-132-5p and miR-212-5p with immunological relevant target genes, such as FKBP1B, KLF4, and SPN, on both RNA and protein level. Our results indicate that these microRNAs fine-tune the expression of immune-related target genes during fungal infection. Beyond that, we identified previously undiscovered microRNAs. We validated three novel microRNAs via qRT-PCR. A comparison with known microRNAs revealed possible relations with the miR-378 family and miR-1260a/b for two of them, while the third one features a unique sequence with no resemblance to known microRNAs. In summary, this study analyzes the effect of known microRNAs in dendritic cells during

  18. Prolonged activation of virus-specific CD8+T cells after acute B19 infection.

    Directory of Open Access Journals (Sweden)

    Adiba Isa

    2005-12-01

    Full Text Available Human parvovirus B19 (B19 is a ubiquitous and clinically significant pathogen, causing erythema infectiosum, arthropathy, transient aplastic crisis, and intrauterine fetal death. The phenotype of CD8+ T cells in acute B19 infection has not been studied previously.The number and phenotype of B19-specific CD8+ T cell responses during and after acute adult infection was studied using HLA-peptide multimeric complexes. Surprisingly, these responses increased in magnitude over the first year post-infection despite resolution of clinical symptoms and control of viraemia, with T cell populations specific for individual epitopes comprising up to 4% of CD8+ T cells. B19-specific T cells developed and maintained an activated CD38+ phenotype, with strong expression of perforin and CD57 and downregulation of CD28 and CD27. These cells possessed strong effector function and intact proliferative capacity. Individuals tested many years after infection exhibited lower frequencies of B19-specific cytotoxic T lymphocytes, typically 0.05%-0.5% of CD8+ T cells, which were perforin, CD38, and CCR7 low.This is the first example to our knowledge of an "acute" human viral infection inducing a persistent activated CD8+ T cell response. The likely explanation--analogous to that for cytomegalovirus infection--is that this persistent response is due to low-level antigen exposure. CD8+ T cells may contribute to the long-term control of this significant pathogen and should be considered during vaccine development.

  19. Prolonged activation of virus-specific CD8+T cells after acute B19 infection.

    Directory of Open Access Journals (Sweden)

    2005-12-01

    Full Text Available BACKGROUND: Human parvovirus B19 (B19 is a ubiquitous and clinically significant pathogen, causing erythema infectiosum, arthropathy, transient aplastic crisis, and intrauterine fetal death. The phenotype of CD8+ T cells in acute B19 infection has not been studied previously. METHODS AND FINDINGS: The number and phenotype of B19-specific CD8+ T cell responses during and after acute adult infection was studied using HLA-peptide multimeric complexes. Surprisingly, these responses increased in magnitude over the first year post-infection despite resolution of clinical symptoms and control of viraemia, with T cell populations specific for individual epitopes comprising up to 4% of CD8+ T cells. B19-specific T cells developed and maintained an activated CD38+ phenotype, with strong expression of perforin and CD57 and downregulation of CD28 and CD27. These cells possessed strong effector function and intact proliferative capacity. Individuals tested many years after infection exhibited lower frequencies of B19-specific cytotoxic T lymphocytes, typically 0.05%-0.5% of CD8+ T cells, which were perforin, CD38, and CCR7 low. CONCLUSION: This is the first example to our knowledge of an "acute" human viral infection inducing a persistent activated CD8+ T cell response. The likely explanation--analogous to that for cytomegalovirus infection--is that this persistent response is due to low-level antigen exposure. CD8+ T cells may contribute to the long-term control of this significant pathogen and should be considered during vaccine development.

  20. Diagnostic performances of two rapid tests for detection of feline leukemia virus antigen in sera of experimentally feline leukemia virus-infected cats

    Directory of Open Access Journals (Sweden)

    Matthew R Krecic

    2017-12-01

    Full Text Available Objectives The objective of this study was to compare the diagnostic sensitivities and specificities of WITNESS FeLV-FIV (Zoetis and SNAP FIV/FeLV Combo Test (IDEXX for the detection of FeLV p27 antigen in the sera of experimentally feline leukemia virus (FeLV-infected cats. Methods Diagnostic sensitivities of WITNESS and SNAP were determined through testing of 47 serum samples collected from cats day 56 post-experimental infection with a virulent FeLV Rickard strain. Successful experimental infection was confirmed based on observation of FeLV antigen and proviral DNA in anti-coagulated (EDTA whole-blood samples by immunofluorescent antibody (IFA test and PCR, respectively. Diagnostic specificities of both tests were determined through testing of sera of 92 laboratory-housed, non-FeLV-exposed specific pathogen-free (SPF cats. Results Forty-one of 47 blood samples were IFA positive, whereas all 47 samples were PCR positive. All 92 non-FeLV-infected SPF cats were IFA and PCR negative. In comparison to IFA as the reference method, both WITNESS and SNAP tests yielded equivalent sensitivities and specificities of 100% and 97.8%, respectively. In comparison to PCR as the reference method, both WITNESS and SNAP tests likewise performed equivalently, with sensitivities and specificities of 91.5% and 100%, respectively. Conclusions and relevance Sensitivity and specificity of WITNESS FeLV-FIV for identifying FeLV p27 antigen in the sera of these experimentally FeLV-infected and non-FeLV-exposed SPF cats equaled those of the SNAP FIV/FeLV Combo Test. However, all positive results, regardless of the point-of-care test used, should be confirmed before making clinical decisions such as segregation from other cats or euthanasia.

  1. Studies on vertical transmission of Trichinella spiralis in experimentally infected guinea pigs (Cavia porcellus).

    Science.gov (United States)

    Riva, Eliana; Fiel, Cesar; Bernat, Gisele; Muchiut, Sebastián; Steffan, Pedro

    2017-08-01

    An experimental study to enhance knowledge on the capability of Trichenella spiralis to pass from guinea pigs to progeny at different periods of pregnancy or lactation was performed. For this purpose, 18 female adult guinea pigs were inoculated with 100 or 1000 T. spiralis muscle larvae (ML) during early, late gestation and during lactation period. The presence of T. spiralis (ML) in mothers and newborns was studied through enzymatic digestion from muscle samples. ML were observed in 9 of 42 newborn guinea pigs and levels of infection were significantly higher when infections of mothers were done during late gestation (p = 0.0046) with the high infective dose (p = 0.0043). T. spiralis ML were not recovered from any of the newborns from mothers infected in the lactation period. Ten out of 18 infected mothers presented larvae 1 in their mammary glands. Muscle samples from the tongue and the masseter showed the highest larval burdens. These observations confirm previous reports on that ML of T. spiralis are capable to pass through placental tissues to reach and encyst in striated muscle groups of newborn guinea pigs. This study may also reinforce the importance of preventive programs to control trichinellosis in those endemic areas where pregnant women would have high risk of infection.

  2. Experimental Infection and Clearance of Coccidian Parasites in Mercury-Exposed Zebra Finches.

    Science.gov (United States)

    Ebers Smith, Jessica H; Cristol, Daniel A; Swaddle, John P

    2018-01-01

    Mercury is a globally distributed, persistent environmental contaminant that affects the health of many taxa. It can suppress the immune system, which often plays a role in defense against parasites. However, there have been few investigations of whether mercury affects the abilities of animals to resist parasitic infection. Here, we exposed zebra finches to a lifetime dietary exposure of methylmercury (1.2 μg/g wet weight) and experimentally infected them with coccidian parasites to examine the effect of methylmercury exposure on parasitic infection. The mercury-exposed birds did not have an altered immune response (heterophil:lymphocyte ratio) nor a reduced ability to clear the infection. However, mercury-exposed birds tended to have higher parasite loads at the time when we expected the greatest immune response (2-3 weeks post-infection). Although mercury did not greatly influence the infection-course of this parasite in captivity, responses may be more accentuated in the wild where birds face additional immune challenges.

  3. Virus-specific cytotoxic T cells in chronic active Epstein-Barr virus infection.

    Science.gov (United States)

    Shibayama, Haruna; Imadome, Ken-Ichi; Onozawa, Erika; Tsuzura, Akiho; Miura, Osamu; Koyama, Takatoshi; Arai, Ayako

    2017-01-01

    Chronic active Epstein-Barr virus infection (CAEBV) is a disease characterized by clonally proliferating and activated EBV-infected T or NK cells accompanied by chronic inflammation and T- or NK-cell neoplasms. However, the mechanism for developing CAEBV has not been clarified to date. Because the decreased number or inactivation of EBV-specific cytotoxic T lymphocytes (CTLs) resulted in the development of EBV-positive B-cell neoplasms, we investigated the number of CTLs in CAEBV patients using the tetrameric complexes of HLA-restricted EBV-specific peptides. Among the seven patients examined, EBV-specific CTLs were detected in the peripheral blood mononuclear cells (PBMCs) of four cases but were not detected in three cases. The ratio of EBV-specific CTLs in PBMCs tended to be higher in the patients with active disease than in those with inactive disease. In two patients in whom EBV-specific CTLs had not been detected, CTLs appeared after the eradication of EBV-infected T cells by allogeneic bone marrow transplantation. These results suggested that the failure of CTLs had a role in developing CAEBV, although the induction number and function of EBV-specific CTLs might vary in each patient.

  4. Experimental infection of snakes with Ophidiomyces ophiodiicola causes pathological changes that typify snake fungal disease

    Science.gov (United States)

    Lorch, Jeffrey M.; Lankton, Julia S.; Werner, Katrien; Falendysz, Elizabeth A.; McCurley, Kevin; Blehert, David S.

    2015-01-01

    Snake fungal disease (SFD) is an emerging skin infection of wild snakes in eastern North America. The fungus Ophidiomyces ophiodiicola is frequently associated with the skin lesions that are characteristic of SFD, but a causal relationship between the fungus and the disease has not been established. We experimentally infected captive-bred corn snakes (Pantherophis guttatus) in the laboratory with pure cultures of O. ophiodiicola. All snakes in the infected group (n = 8) developed gross and microscopic lesions identical to those observed in wild snakes with SFD; snakes in the control group (n = 7) did not develop skin infections. Furthermore, the same strain of O. ophiodiicola used to inoculate snakes was recovered from lesions of all animals in the infected group, but no fungi were isolated from individuals in the control group. Monitoring progression of lesions throughout the experiment captured a range of presentations of SFD that have been described in wild snakes. The host response to the infection included marked recruitment of granulocytes to sites of fungal invasion, increased frequency of molting, and abnormal behaviors, such as anorexia and resting in conspicuous areas of enclosures. While these responses may help snakes to fight infection, they could also impact host fitness and may contribute to mortality in wild snakes with chronic O. ophiodiicola infection. This work provides a basis for understanding the pathogenicity of O. ophiodiicola and the ecology of SFD by using a model system that incorporates a host species that is easy to procure and maintain in the laboratory.

  5. Sensitivity and Specificity of Empiric Treatment for Sexually Transmitted Infections in a Pediatric Emergency Department.

    Science.gov (United States)

    Breslin, Kristen; Tuchman, Lisa; Hayes, Katie L; Badolato, Gia; Goyal, Monika K

    2017-10-01

    To determine test characteristics of provider judgment for empiric antibiotic provision to patients undergoing testing for a sexually transmitted infection. We conducted a retrospective cross-sectional electronic health record review of all patients aged 13-19 years who had Neisseria gonorrhoeae (GC) and Chlamydia trachomatis (CT) testing sent from an urban, academic pediatric emergency department in 2012. We abstracted data, including patient demographics, chief complaint, sexually transmitted infection test results, and treatment. We calculated test characteristics comparing clinician judgment for presumptive treatment for a sexually transmitted infection with the reference standard of the actual results of testing for a sexually transmitted infection. Of 1223 patient visits meeting inclusion criteria, 284 (23.2%) had a positive GC and/or CT test result. Empiric treatment was provided in 615 encounters (50.3%). Provider judgment for presumptive treatment had an overall sensitivity of 67.6% (95% CI, 61.8-73.0) and a specificity of 55% (95% CI, 51.7-58.2) for accurate GC and/or CT detection. Many adolescents tested for GC and CT receive empiric treatment at the initial emergency department visit. Provider judgment may lack sufficient sensitivity and specificity for identifying infected patients, resulting in the potential for undertreatment of true disease, overtreatment of uninfected patients, or both. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Leptospira interrogans stably infects zebrafish embryos, altering phagocyte behavior and homing to specific tissues.

    Directory of Open Access Journals (Sweden)

    J Muse Davis

    2009-06-01

    Full Text Available Leptospirosis is an extremely widespread zoonotic infection with outcomes ranging from subclinical infection to fatal Weil's syndrome. Despite the global impact of the disease, key aspects of its pathogenesis remain unclear. To examine in detail the earliest steps in the host response to leptospires, we used fluorescently labelled Leptospira interrogans serovar Copenhageni to infect 30 hour post fertilization zebrafish embryos by either the caudal vein or hindbrain ventricle. These embryos have functional innate immunity but have not yet developed an adaptive immune system. Furthermore, they are optically transparent, allowing direct visualization of host-pathogen interactions from the moment of infection. We observed rapid uptake of leptospires by phagocytes, followed by persistent, intracellular infection over the first 48 hours. Phagocytosis of leptospires occasionally resulted in formation of large cellular vesicles consistent with apoptotic bodies. By 24 hours, clusters of infected phagocytes were accumulating lateral to the dorsal artery, presumably in early hematopoietic tissue. Our observations suggest that phagocytosis may be a key defense mechanism in the early stages of leptospirosis, and that phagocytic cells play roles in immunopathogenesis and likely in the dissemination of leptospires to specific target tissues.

  7. Experimental infection of highly pathogenic avian influenza virus H5N1 in black-headed gulls (Chroicocephalus ridibundus)

    OpenAIRE

    Ramis , Antonio; van Amerongen , Geert; van de Bildt , Marco; Leijten , Loneke; Vanderstichel , Raphael; Osterhaus , Albert; Kuiken , Thijs

    2014-01-01

    Historically, highly pathogenic avian influenza viruses (HPAIV) rarely resulted in infection or clinical disease in wild birds. However, since 2002, disease and mortality from natural HPAIV H5N1 infection have been observed in wild birds including gulls. We performed an experimental HPAIV H5N1 infection of black-headed gulls (Chroicocephalus ridibundus) to determine their susceptibility to infection and disease from this virus, pattern of viral shedding, clinical signs, pathological changes a...

  8. Therapy of the experimental infection by Strongyloides venezuelensis in rats with injectable ivermectin or levamizole

    Directory of Open Access Journals (Sweden)

    Rubens Campos

    1989-02-01

    Full Text Available For the therapy of human strongyloidiasis, are necessary effective drugs to eliminate both larvae and adult worm parasitism, which may also be used by parenteral route, to obviate the particular conditions presented by many patients. A study based on the experimental infection by Strongyloides venezuelensis in rats was done, administering injectable ivermectin or levamizole. Both drugs were shown to be active, when used in single doses of 0.2 to 0.5 mg/kg of ivermectin, or 26 mg/kg for levamizole. Ivermectin was slightly more effective as far as larval stage of the infection is concerned, and the same happened for levamisole for the adult worm stage. Promising perspectives are visualized to improve the therapy of patients with serious disseminated infection by Strongyloides stercoralis.

  9. Coronative antibody tires in sera of healthy adults and experimentally infected volunteers.

    Science.gov (United States)

    Bradburne, A F; Somerset, B A

    1972-06-01

    Six coronaviruses isolated in the U.S.A. have been inoculated into volunteers and all produced colds. Between 10 and 20% of infected volunteers developed heterologous antibody responses after these and other experimental infections with coronaviruses. The haemagglutination-inhibition test with the OC43 virus strain was found to detect antibody rises after infection with a variety of strains.Studies on normal adult sera taken between 1965 and 1970 revealed a high frequency of neutralizing antibody to one strain (229 E) and a frequency of HI antibody to strain OC43 which fluctuated from year to year. Complement-fixing antibodies to these two viruses were also found, revealing an apparent increase in the activity of coronaviruses in the general population of the U.K., during the winter of 1968-9.

  10. Nutritional Status Driving Infection by Trypanosoma cruzi: Lessons from Experimental Animals

    Directory of Open Access Journals (Sweden)

    Guilherme Malafaia

    2011-01-01

    Full Text Available This paper reviews the scientific knowledge about protein-energy and micronutrient malnutrition in the context of Chagas disease, especially in experimental models. The search of articles was conducted using the electronic databases of SciELO (Scientific Electronic Library Online, PubMed and MEDLINE published between 1960 and March 2010. It was possible to verify that nutritional deficiencies (protein-energy malnutrition and micronutrient malnutrition exert a direct effect on the infection by T. cruzi. However, little is known about the immunological mechanisms involved in the relationship “nutritional deficiencies and infection by T. cruzi”. A hundred years after the discovery of Chagas disease many aspects of this illness still require clarification, including the effects of nutritional deficiencies on immune and pathological mechanisms of T. cruzi infection.

  11. Correlation of serotype-specific dengue virus infection with clinical manifestations.

    Directory of Open Access Journals (Sweden)

    Eric S Halsey

    Full Text Available Disease caused by the dengue virus (DENV is a significant cause of morbidity throughout the world. Although prior research has focused on the association of specific DENV serotypes (DENV-1, DENV-2, DENV-3, and DENV-4 with the development of severe outcomes such as dengue hemorrhagic fever and dengue shock syndrome, relatively little work has correlated other clinical manifestations with a particular DENV serotype. The goal of this study was to estimate and compare the prevalence of non-hemorrhagic clinical manifestations of DENV infection by serotype.Between the years 2005-2010, individuals with febrile disease from Peru, Bolivia, Ecuador, and Paraguay were enrolled in an outpatient passive surveillance study. Detailed information regarding clinical signs and symptoms, as well as demographic information, was collected. DENV infection was confirmed in patient sera with polyclonal antibodies in a culture-based immunofluorescence assay, and the infecting serotype was determined by serotype-specific monoclonal antibodies. Differences in the prevalence of individual and organ-system manifestations were compared across DENV serotypes. One thousand seven hundred and sixteen individuals were identified as being infected with DENV-1 (39.8%, DENV-2 (4.3%, DENV-3 (41.5%, or DENV-4 (14.4%. When all four DENV serotypes were compared with each other, individuals infected with DENV-3 had a higher prevalence of musculoskeletal and gastrointestinal manifestations, and individuals infected with DENV-4 had a higher prevalence of respiratory and cutaneous manifestations.Specific clinical manifestations, as well as groups of clinical manifestations, are often overrepresented by an individual DENV serotype.

  12. Correlation of Serotype-Specific Dengue Virus Infection with Clinical Manifestations

    Science.gov (United States)

    Halsey, Eric S.; Marks, Morgan A.; Gotuzzo, Eduardo; Fiestas, Victor; Suarez, Luis; Vargas, Jorge; Aguayo, Nicolas; Madrid, Cesar; Vimos, Carlos; Kochel, Tadeusz J.; Laguna-Torres, V. Alberto

    2012-01-01

    Background Disease caused by the dengue virus (DENV) is a significant cause of morbidity throughout the world. Although prior research has focused on the association of specific DENV serotypes (DENV-1, DENV-2, DENV-3, and DENV-4) with the development of severe outcomes such as dengue hemorrhagic fever and dengue shock syndrome, relatively little work has correlated other clinical manifestations with a particular DENV serotype. The goal of this study was to estimate and compare the prevalence of non-hemorrhagic clinical manifestations of DENV infection by serotype. Methodology and Principal Findings Between the years 2005–2010, individuals with febrile disease from Peru, Bolivia, Ecuador, and Paraguay were enrolled in an outpatient passive surveillance study. Detailed information regarding clinical signs and symptoms, as well as demographic information, was collected. DENV infection was confirmed in patient sera with polyclonal antibodies in a culture-based immunofluorescence assay, and the infecting serotype was determined by serotype-specific monoclonal antibodies. Differences in the prevalence of individual and organ-system manifestations were compared across DENV serotypes. One thousand seven hundred and sixteen individuals were identified as being infected with DENV-1 (39.8%), DENV-2 (4.3%), DENV-3 (41.5%), or DENV-4 (14.4%). When all four DENV serotypes were compared with each other, individuals infected with DENV-3 had a higher prevalence of musculoskeletal and gastrointestinal manifestations, and individuals infected with DENV-4 had a higher prevalence of respiratory and cutaneous manifestations. Conclusions/Significance Specific clinical manifestations, as well as groups of clinical manifestations, are often overrepresented by an individual DENV serotype. PMID:22563516

  13. Excretion of [3H]prednisolone in clinically normal and experimentally infected bovine udders

    International Nuclear Information System (INIS)

    Geleta, J.N.; Shimoda, W.; Mercer, H.D.

    1984-01-01

    The excretion rate of [3H]prednisolone from clinically normal and experimentally infected udders of 10 lactating cows was studied. Each quarter of 6 cows was injected with a single dose of [3H]prednisolone mixed with non-radioactive prednisolone equivalent to 10 mg in 10 ml of peanut oil base. Each of the remaining 4 cows was given 40 mg of nonradioactive prednisolone and [3H]prednisolone in 60% ethanol IV. Control and postadministration samples of blood, milk, and urine were examined for radioactivity. The effects of [3H]prednisolone were evaluated in the same cows, first in clinically normal udders, then 2 weeks later in udders experimentally infected with Streptococcus agalactiae. Absorption and elimination of prednisolone were the same before and after induced infection. Within 3 hours after intramammary injection, 95% of the labeled prednisolone was absorbed systemically, less than 5% of this dose was recovered in milk, and 29% was excreted in urine. After IV injection of [3H]prednisolone, less than 0.2% of the total radioactivity was recovered in milk and less than 46% was excreted in urine. Clinical mastitis induced by S agalactiae was moderate. Circulating blood leukocytes and somatic cells in the milk of normal cows remained essentially unchanged. The leukocyte response to induced infection was rapid in blood and milk. Large numbers of leukocytes were noticed in the milk and a severe leukopenia occurred. Prednisolone treatment did not alter the number of somatic cells in milk or reduce the inflammatory response of experimentally infected cows

  14. Excretion of (3H)prednisolone in clinically normal and experimentally infected bovine udders

    Energy Technology Data Exchange (ETDEWEB)

    Geleta, J.N.; Shimoda, W.; Mercer, H.D.

    1984-08-01

    The excretion rate of (3H)prednisolone from clinically normal and experimentally infected udders of 10 lactating cows was studied. Each quarter of 6 cows was injected with a single dose of (3H)prednisolone mixed with non-radioactive prednisolone equivalent to 10 mg in 10 ml of peanut oil base. Each of the remaining 4 cows was given 40 mg of nonradioactive prednisolone and (3H)prednisolone in 60% ethanol IV. Control and postadministration samples of blood, milk, and urine were examined for radioactivity. The effects of (3H)prednisolone were evaluated in the same cows, first in clinically normal udders, then 2 weeks later in udders experimentally infected with Streptococcus agalactiae. Absorption and elimination of prednisolone were the same before and after induced infection. Within 3 hours after intramammary injection, 95% of the labeled prednisolone was absorbed systemically, less than 5% of this dose was recovered in milk, and 29% was excreted in urine. After IV injection of (3H)prednisolone, less than 0.2% of the total radioactivity was recovered in milk and less than 46% was excreted in urine. Clinical mastitis induced by S agalactiae was moderate. Circulating blood leukocytes and somatic cells in the milk of normal cows remained essentially unchanged. The leukocyte response to induced infection was rapid in blood and milk. Large numbers of leukocytes were noticed in the milk and a severe leukopenia occurred. Prednisolone treatment did not alter the number of somatic cells in milk or reduce the inflammatory response of experimentally infected cows.

  15. Anatomopathological study in BALB/c mice brains experimentally infected with Toxoplasma gondii

    Directory of Open Access Journals (Sweden)

    Marcos Gontijo da Silva

    Full Text Available Toxoplasmosis is one of the most important diseases of the nervous central system, leading to severe symptoms and, many times, irreversible sequelae. This work demonstrated the main anatomopathological lesions caused by Toxoplasma gondii in brains from experimentally infected BALB/c mice. We analyzed 51 cases of mice that developed toxoplasmosis after experimental infection by intraperitoneal inoculation of blood, amniotic liquid and cerebrospinal fluid from fetuses, newly born children and pregnant women with clinical and laboratory signals of toxoplasmosis. In all experiments where we detected the parasite in mice we also detected pathological lesions in the animal brains with great polymorphism between experiments. Edema was the most found lesion in all cases. Besides, it was possible to demonstrate the inflammatory process in 82.4% of cases and necrosis in 64.7% of cases, in agreement with the literature that describes severe neurological damage in its hosts.

  16. Pathogenesis of reproductive failure induced by Trypanosoma vivax in experimentally infected pregnant ewes

    Science.gov (United States)

    2013-01-01

    The present study was aimed at investigating the effect of experimental infection by Trypanosoma vivax in different stages of pregnancy, determining the pathogenesis of reproductive failure, and confirming transplacental transmission. We used 12 pregnant ewes distributed into four experimental groups: G1, was formed by three ewes infected with T. vivax in the first third of pregnancy (30 days); G2 comprised three infected ewes in the final third of pregnancy (100 days); G3 and G4 were composed of three non-infected ewes with the same gestational period, respectively. Each ewe of G1 and G2 was inoculated with 1.25 × 105 tripomastigotes. Clinical examination, determination of parasitemia, serum biochemistry (albumin, total protein, glucose, cholesterol, and urea), packed cell volume (PCV), serum progesterone, and pathological examination were performed. Placenta, amniotic fluid, blood and tissues from the fetuses and stillbirths were submitted to PCR. Two ewes of G1 (Ewe 1 and 3) presented severe infection and died in the 34th and 35th days post-infection (dpi), respectively; but both fetuses were recovered during necropsy. In G2, Ewe 5 aborted two fetuses on the 130th day (30 dpi) of pregnancy; and Ewe 6 aborted one fetus in the 140th day (40 dpi) of gestation. Ewes 2 and 4 delivered two weak lambs that died five days after birth. Factors possibly involved with the reproductive failure included high parasitemia, fever, low PCV, body score, serum glucose, total protein, cholesterol, and progesterone. Hepatitis, pericarditis, and encephalitis were observed in the aborted fetuses. The presence of T. vivax DNA in the placenta, amniotic fluid, blood, and tissues from the fetuses confirms the transplacental transmission of the parasite. Histological lesion in the fetuses and placenta also suggest the involvement of the parasite in the etiopathogenesis of reproductive failure in ewes. PMID:23289625

  17. Humans with chimpanzee-like major histocompatibility complex-specificities control HIV-1 infection

    DEFF Research Database (Denmark)

    Hoof, Ilka; Kesmir, Can; Lund, Ole

    2008-01-01

    and the progression rate to AIDS. Chimpanzees control HIV-1 viral replication and develop a chronic infection without progressing to AIDS. A similar course of disease is observed in human long-term non-progressors. Objective: To investigate if long-term non-progressors and chimpanzees have functional similarities...... in their MHC class I repertoire. Methods: We compared the specificity of groups of human MHC molecules associated with different levels of viremia in HIV-1 infected individuals with those of chimpanzee. Results and conclusion: We demonstrate that human MHC with control of HIV-1 viral load share binding motifs...... with chimpanzee MHC. Moreover, we find that chimpanzee and human MHC associated with low viral load are predicted to elicit broader Gag-specific immune responses than human MHC associated with high viral load, thus supporting earlier findings that Gag-specific immune responses are essential for HIV-1 control....

  18. Characterising the mucosal and systemic immune responses to experimental human hookworm infection.

    Directory of Open Access Journals (Sweden)

    Soraya Gaze

    2012-02-01

    Full Text Available The mucosal cytokine response of healthy humans to parasitic helminths has never been reported. We investigated the systemic and mucosal cytokine responses to hookworm infection in experimentally infected, previously hookworm naive individuals from non-endemic areas. We collected both peripheral blood and duodenal biopsies to assess the systemic immune response, as well as the response at the site of adult worm establishment. Our results show that experimental hookworm infection leads to a strong systemic and mucosal Th2 (IL-4, IL-5, IL-9 and IL-13 and regulatory (IL-10 and TGF-β response, with some evidence of a Th1 (IFN-γ and IL-2 response. Despite upregulation after patency of both IL-15 and ALDH1A2, a known Th17-inducing combination in inflammatory diseases, we saw no evidence of a Th17 (IL-17 response. Moreover, we observed strong suppression of mucosal IL-23 and upregulation of IL-22 during established hookworm infection, suggesting a potential mechanism by which Th17 responses are suppressed, and highlighting the potential that hookworms and their secreted proteins offer as therapeutics for human inflammatory diseases.

  19. Efficacy of albendazole against Taenia multiceps larvae in experimentally infected goats.

    Science.gov (United States)

    Afonso, Sónia M S; Neves, Luis; Pondja, Alberto; Macuamule, Cristiano; Mukaratirwa, Samson; Arboix, Margarita; Cristòfol, Carles; Capece, Bettencourt P S

    2014-12-15

    A controlled trial was conducted to evaluate the efficacy of three therapeutics regimes of albendazole (ABZ) against Taenia multiceps larvae in experimental infected goats. Forty-nine goats experimentally infected with 3000 T. multiceps eggs were selected and randomly divided into treatment or control groups. Treatment with 10mg/kg for 3 days for group 1 (G1), 10mg/kg for group 2 (G2) and 20mg/kg/day for group 3 (G3) was applied 2 months after infection; group 4 (G4) served as a control group. A treatment with doses of 10mg/kg/day for 3 days on group 5 (G5) and group 6 (G6) was used as control, 5 months after the infection. The efficacy of ABZ was assessed as percentage of non-viable cysts which were determined by morphologic characteristics, movement and methyl blue staining technique. The efficacy of ABZ against 2 months old cysts was significantly different from the control and were 90.3% (28/31), 72.7% (8/11) and 73.9% (14/19) for G1, G2 and G3, respectively. No differences were observed in cyst viability between treated and control groups for 5-month old cysts. The results in this study indicate that ABZ is effective in goats against 2-month-old cysts of T. multiceps larva located in tissues outside the brain. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Avian influenza in shorebirds: experimental infection of ruddy turnstones (Arenaria interpres) with avian influenza virus

    OpenAIRE

    Hall, Jeffrey S.; Krauss, Scott; Franson, J. Christian; TeSlaa, Joshua L.; Nashold, Sean W.; Stallknecht, David E.; Webby, Richard J.; Webster, Robert G.

    2012-01-01

    Please cite this paper as: Hall et al. (2012) Avian influenza in shorebirds: experimental infection of ruddy turnstones (Arenaria interpres) with avian influenza virus. Influenza and Other Respiratory Viruses DOI: 10.1111/j.1750‐2659.2012.00358.x. Background  Low pathogenic avian influenza viruses (LPAIV) have been reported in shorebirds, especially at Delaware Bay, USA, during spring migration. However, data on patterns of virus excretion, minimal infectious doses, and clinical outcome are l...

  1. Ketoconazole modulates the infectivity of Ichthyophonus sp. (Mesomycetozoa) in vivo in experimentally injected European sea bass

    OpenAIRE

    Hontoria, Francisco; González, Mª Ángeles; Sitjà-Bobadilla, Ariadna; Palenzuela, Oswaldo

    2013-01-01

    In vitro studies have confirmed the inhibitory effect of the azol-derivative ketoconazole (KZ) on the growth of Ichthyophonus, an important pathogen causing epizootics in wild and cultured fish. We evaluated the effect of KZ in vivo in European sea bass Dicentrarchus labrax experimentally infected with the same Ichthyophonus isolate. Liposomes were used to vehiculate different doses of KZ to increase the effect on Ichthyophonus and lower the toxicity of the drug, and KZ toxicity was assessed ...

  2. Infectious mononucleosis, other infections and prostate-specific antigen concentration as a marker of prostate involvement during infection.

    Science.gov (United States)

    Sutcliffe, Siobhan; Nevin, Remington L; Pakpahan, Ratna; Elliott, Debra J; Langston, Marvin E; De Marzo, Angelo M; Gaydos, Charlotte A; Isaacs, William B; Nelson, William G; Sokoll, Lori J; Walsh, Patrick C; Zenilman, Jonathan M; Cersovsky, Steven B; Platz, Elizabeth A

    2016-05-01

    Although Epstein-Barr virus has been detected in prostate tissue, no associations have been observed with prostate cancer in the few studies conducted to date. One possible reason for these null findings may be use of cumulative exposure measures that do not inform the timing of infection, i.e., childhood versus adolescence/early adulthood when infection is more likely to manifest as infectious mononucleosis (IM). We sought to determine the influence of young adult-onset IM on the prostate by measuring prostate-specific antigen (PSA) as a marker of prostate inflammation/damage among U.S. military members. We defined IM cases as men diagnosed with IM from 1998 to 2003 (n = 55) and controls as men without an IM diagnosis (n = 255). We selected two archived serum specimens for each participant, the first collected after diagnosis for cases and one randomly selected from 1998 to 2003 for controls (index), as well as the preceding specimen (preindex). PSA was measured in each specimen. To explore the specificity of our findings for prostate as opposed to systemic inflammation, we performed a post hoc comparison of other infectious disease cases without genitourinary involvement (n = 90) and controls (n = 220). We found that IM cases were more likely to have a large PSA rise than controls (≥ 20 ng/mL: 19.7% versus 8.8%, p = 0.027; ≥ 40% rise: 25.7% versus 9.4%, p = 0.0021), as were other infectious disease cases (25.7% versus 14.0%, p = 0.020; 27.7% versus 18.0%, p = 0.092). These findings suggest that, in addition to rising because of prostate infection, PSA may also rise because of systemic inflammation, which could have implications for PSA interpretation in older men. © 2015 UICC.

  3. Sarcocystis neurona infections in raccoons (Procyon lotor): evidence for natural infection with sarcocysts, transmission of infection to opossums (Didelphis virginiana), and experimental induction of neurologic disease in raccoons.

    Science.gov (United States)

    Dubey, J P; Saville, W J; Stanek, J F; Lindsay, D S; Rosenthal, B M; Oglesbee, M J; Rosypal, A C; Njoku, C J; Stich, R W; Kwok, O C; Shen, S K; Hamir, A N; Reed, S M

    2001-10-24

    Equine protozoal myeloencephalitis (EPM) is a serious neurologic disease of horses in the Americas and Sarcocystis neurona is the most common etiologic agent. The distribution of S. neurona infections follows the geographical distributions of its definitive hosts, opossums (Didelphis virginiana, Didelphis albiventris). Recently, cats and skunks were reported as experimental and armadillos as natural intermediate hosts of S. neurona. In the present report, raccoons (Procyon lotor) were identified as a natural intermediate host of S. neurona. Two laboratory-raised opossums were found to shed S. neurona-like sporocysts after ingesting tongues of naturally-infected raccoons. Interferon-gamma gene knockout (KO) mice fed raccoon-opossum-derived sporocysts developed neurologic signs. S. neurona was identified immunohistochemically in tissues of KO mice fed sporocysts and the parasite was isolated in cell cultures inoculated with infected KO mouse tissues. The DNA obtained from the tongue of a naturally-infected raccoon, brains of KO mice that had neurological signs, and from the organisms recovered in cell cultures inoculated with brains of neurologic KO mice, corresponded to that of S. neurona. Two raccoons fed mature S. neurona sarcocysts did not shed sporocysts in their feces, indicating raccoons are not likely to be its definitive host. Two raccoons fed sporocysts from opossum feces developed clinical illness and S. neurona-associated encephalomyelitis was found in raccoons killed 14 and 22 days after feeding sporocysts; schizonts and merozoites were seen in encephalitic lesions.

  4. Experimental infection of cattle, sheep and pigs with 'Hobi'-like pestivirus.

    Science.gov (United States)

    Decaro, Nicola; Mari, Viviana; Lucente, Maria Stella; Sciarretta, Rossana; Moreno, Ana; Armenise, Carlo; Losurdo, Michele; Camero, Michele; Lorusso, Eleonora; Cordioli, Paolo; Buonavoglia, Canio

    2012-03-23

    To date, limited information is available on the ability of 'Hobi'-like pestiviruses (putative bovine viral diarrhoea 3) to infect and cause disease in animal species traditionally affected by pestiviruses. In order to obtain new insights into host range and pathogenic potential of this atypical pestivirus, BVDV-seronegative calves (n=5), lambs (n=5) and piglets (n=5) were experimentally infected with the European 'Hobi'-like strain Italy-1/10-1, whereas two animals per species served as uninfected controls. Appearance of clinical signs, leukopenia, viremia, viral shedding and seroconversion were monitored for 28 days post-infection. Calves and lambs were successfully infected, displaying respiratory signs (nasal discharge), moderate hyperthermia and leukopenia, viremia and viral shedding through the nasal and faecal routes. Antibody responses were observed in both animal species by ELISA and virus neutralisation assays. In contrast, inoculated piglets did not display any clinical signs nor leukopenia and viral RNA was not detected in any biological samples. Nevertheless, the presence of detectable antibodies by virus neutralisation accounted for a successful, albeit limited infection of these animals. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Experimental infection of two South American reservoirs with four distinct strains of Trypanosoma cruzi

    Science.gov (United States)

    Roellig, Dawn M.; McMillan, Katherine; Ellis, Angela E.; Vandeberg, John L.; Champagne, Donald E.; Yabsley, Michael J.

    2010-01-01

    SUMMARY Trypanosoma cruzi (Tc), the causative agent of Chagas disease, is a diverse species with 2 primary genotypes, TcI and TcII, with TcII further subdivided into 5 subtypes (IIa–e). This study evaluated infection dynamics of 4 genetically and geographically diverse T. cruzi strains in 2 South American reservoirs, degus (Octodon degus) and grey short-tailed opossums (Monodelphis domestica). Based on prior suggestions of a genotype-host association, we hypothesized that degus (placental) would more readily become infected with TcII strains while short-tailed opossums (marsupial) would be a more competent reservoir for a TcI strain. Individuals (n = 3) of each species were intraperitoneally inoculated with T. cruzi trypomastigotes of TcIIa [North America (NA)-raccoon (Procyon lotor) origin], TcI [NA-Virginia opossum (Didelphis virginiana)], TcIIb [South America (SA)-human], TcIIe (SA-Triatoma infestans), or both TcI and TcIIa. Parasitaemias in experimentally infected degus peaked earlier (7–14 days post-inoculation (p.i.)) compared with short-tailed opossums (21–84 days p.i.). Additionally, peak parasitaemias were higher in degus; however, the duration of detectable parasitaemias for all strains, except TcIIa, was greater in short-tailed opossums. Infections established in both host species with all genotypes, except for TcIIa, which did not establish a detectable infection in short-tailed opossums. These results indicate that both South American reservoirs support infections with these isolates from North and South America; however, infection dynamics differed with host and parasite strain. PMID:20128943

  6. Different infective forms trigger distinct immune response in experimental Chagas disease.

    Directory of Open Access Journals (Sweden)

    Paula Melo de Abreu Vieira

    Full Text Available Although metacyclic and blood trypomastigotes are completely functional in relation to parasite-host interaction and/or target cell invasion, they differ in the molecules present on the surface. Thus, aspects related to the variability that the forms of T. cruzi interacts with host cells may lead to fundamental implications on the immune response against this parasite and, consequently, the clinical evolution of Chagas disease. We have shown that BT infected mice presented higher levels of parasitemia during all the acute phase of infection. Moreover, the infection with either MT or BT forms resulted in increased levels of total leukocytes, monocytes and lymphocytes, specifically later for MT and earlier for BT. The infection with BT forms presented earlier production of proinflammatory cytokine TNF-α and later of IFN-γ by both T cells subpopulations. This event was accompanied by an early cardiac inflammation with an exacerbation of this process at the end of the acute phase. On the other hand, infection with MT forms result in an early production of IFN-γ, with subsequent control in the production of this cytokine by IL-10, which provided to these animals an immunomodulatory profile in the end of the acute phase. These results are in agreement with what was found for cardiac inflammation where animals infected with MT forms showed intense cardiac inflammation later at infection, with a decrease in the same at the end of this phase. In summary, our findings emphasize the importance of taking into account the inoculums source of T. cruzi, since vectorial or transfusional routes of T. cruzi infection may trigger distinct parasite-host interactions during the acute phase that may influence relevant biological aspects of chronic Chagas disease.

  7. Elevated Cancer-Specific Mortality Among HIV-Infected Patients in the United States.

    Science.gov (United States)

    Coghill, Anna E; Shiels, Meredith S; Suneja, Gita; Engels, Eric A

    2015-07-20

    Despite advances in the treatment of HIV, HIV-infected people remain at increased risk for many cancers, and the number of non-AIDS-defining cancers is increasing with the aging of the HIV-infected population. No prior study has comprehensively evaluated the effect of HIV on cancer-specific mortality. We identified cases of 14 common cancers occurring from 1996 to 2010 in six US states participating in a linkage of cancer and HIV/AIDS registries. We used Cox regression to examine the association between patient HIV status and death resulting from the presenting cancer (ascertained from death certificates), adjusting for age, sex, race/ethnicity, year of cancer diagnosis, and cancer stage. We included 1,816,461 patients with cancer, 6,459 (0.36%) of whom were HIV infected. Cancer-specific mortality was significantly elevated in HIV-infected compared with HIV-uninfected patients for many cancers: colorectum (adjusted hazard ratio [HR], 1.49; 95% CI, 1.21 to 1.84), pancreas (HR, 1.71; 95% CI, 1.35 to 2.18), larynx (HR, 1.62; 95% CI, 1.06 to 2.47), lung (HR, 1.28; 95% CI, 1.17 to 1.39), melanoma (HR, 1.72; 95% CI, 1.09 to 2.70), breast (HR, 2.61; 95% CI, 2.06 to 3.31), and prostate (HR, 1.57; 95% CI, 1.02 to 2.41). HIV was not associated with increased cancer-specific mortality for anal cancer, Hodgkin lymphoma, or diffuse large B-cell lymphoma. After further adjustment for cancer treatment, HIV remained associated with elevated cancer-specific mortality for common non-AIDS-defining cancers: colorectum (HR, 1.40; 95% CI, 1.09 to 1.80), lung (HR, 1.28; 95% CI, 1.14 to 1.44), melanoma (HR, 1.93; 95% CI, 1.14 to 3.27), and breast (HR, 2.64; 95% CI, 1.86 to 3.73). HIV-infected patients with cancer experienced higher cancer-specific mortality than HIV-uninfected patients, independent of cancer stage or receipt of cancer treatment. The elevation in cancer-specific mortality among HIV-infected patients may be attributable to unmeasured stage or treatment differences as well

  8. Immuno PET/MR imaging allows specific detection of Aspergillus fumigatus lung infection in vivo

    DEFF Research Database (Denmark)

    Rolle, Anna-Maria; Hasenberg, Mike; Thornton, Christopher R.

    2016-01-01

    -infected mice allowed specific localization of lung infection when combined with PET. Optical imaging with a fluorochrome-labeled version of the mAb showed colocalization with invasive hyphae. The mAb-based newly developed PET tracer [64Cu]DOTA-JF5 distinguishedIPA from bacterial lung infections and...

  9. Identification of toxocara canis antigens by Western blot in experimentally infected rabbits

    Directory of Open Access Journals (Sweden)

    MORALES Olga Lucía

    2002-01-01

    Full Text Available Toxocariasis is a frequent helminthiasis that can cause visceral and ocular damage in humans specially in children. The identification of specific antigens of Toxocara canis is important in order to develop better diagnostic techniques. Ten rabbits were infected orally with a dose of 5000 Toxocara canis embryonated eggs. Rabbits were bled periodically and an ELISA assay was performed to determine levels of specific Toxocara IgG antibodies. ELISA detected antibodies at day 15 after infection. Western blot (WB assay was performed using excretory/secretory antigens (E/S of T. canis second stage larvae. Different antigen concentrations were evaluated: 150, 200, 250 and 300 µg/mL. The concentration of 250 µg/mL was retained for analysis. Rabbit sera were diluted 1:100. Secondary antibody was used at a dilution of 1:1000. Results of WB indicated that in the first month after infection specific antibodies against the 200 KDa, 116 KDa, 92 KDa and 35 KDa antigens were detected; antibodies against the 92 KDa, 80 KDa, 66 KDa, 45 KDa, 31 KDa and 28 KDa antigens appeared later. All positive sera in the ELISA test were also positive in WB. Two antigen bands, 92 KDa and 35 KDa, were identified since the beginning and throughout the course of infection. These antigens merit further evaluation as candidates for use in diagnosis.

  10. Experimental infection of duck origin virulent Newcastle disease virus strain in ducks.

    Science.gov (United States)

    Dai, Yabin; Cheng, Xu; Liu, Mei; Shen, Xinyue; Li, Jianmei; Yu, Shengqing; Zou, Jianmin; Ding, Chan

    2014-07-17

    Newcastle disease (ND) caused by virulent Newcastle disease virus (NDV) is an acute, highly contagious and fatal viral disease affecting most species of birds. Ducks are generally considered to be natural reservoirs or carriers of NDV while being resistant to NDV strains, even those most virulent for chickens; however, natural ND cases in ducks have been gradually increasing in recent years. In the present study, ducks of different breeds and ages were experimentally infected with duck origin virulent NDV strain duck/Jiangsu/JSD0812/2008 (JSD0812) by various routes to investigate the pathogenicity of NDV in ducks. Six breeds (mallard, Gaoyou, Shaoxing, Jinding, Shanma, and Pekin ducks) were infected intramuscularly (IM) with JSD0812 strain at the dose of 5 × 108 ELD50. Susceptibility to NDV infection among breeds varied, per morbidity and mortality. Mallard ducks were the most susceptible, and Pekin ducks the most resistant. Fifteen-, 30-, 45-, 60-, and 110-day-old Gaoyou ducks were infected with JSD0812 strain at the dose of 5 × 108 ELD50 either IM or intranasally (IN) and intraocularly (IO), and their disease development, viral shedding, and virus tissue distribution were determined. The susceptibility of ducks to NDV infection decreased with age. Most deaths occurred in 15- and 30-day-old ducklings infected IM. Ducks infected IN and IO sometimes exhibited clinical signs, but seldom died. Clinical signs were primarily neurologic. Infected ducks could excrete infectious virus from the pharynx and/or cloaca for a short period, which varied with bird age or inoculation route; the longest period was about 7 days. The rate of virus isolation in tissues from infected ducks was generally low, even in those from dead birds, and it appeared to be unrelated to bird age and infection route. The results confirmed that some of the naturally occurring NDV virulent strains can cause the disease in ducks, and that ducks play an important role in the epidemiology of ND. The

  11. Nipah virus infects specific subsets of porcine peripheral blood mononuclear cells.

    Directory of Open Access Journals (Sweden)

    Beata Stachowiak

    Full Text Available Nipah virus (NiV, a zoonotic paramyxovirus, is highly contagious in swine, and can cause fatal infections in humans following transmission from the swine host. The main viral targets in both species are the respiratory and central nervous systems, with viremia implicated as a mode of dissemination of NiV throughout the host. The presented work focused on the role of peripheral blood mononuclear cells (PBMC in the viremic spread of the virus in the swine host. B lymphocytes, CD4-CD8-, as well as CD4+CD8- T lymphocytes were not permissive to NiV, and expansion of the CD4+CD8- cells early post infection was consistent with functional humoral response to NiV infection observed in swine. In contrast, significant drop in the CD4+CD8- T cell frequency was observed in piglets which succumbed to the experimental infection, supporting the hypothesis that antibody development is the critical component of the protective immune response. Productive viral replication was detected in monocytes, CD6+CD8+ T lymphocytes and NK cells by recovery of infectious virus in the cell supernatants. Virus replication was supported by detection of the structural N and the non-structural C proteins or by detection of genomic RNA increase in the infected cells. Infection of T cells carrying CD6 marker, a strong ligand for the activated leukocyte cell adhesion molecule ALCAM (CD166 highly expressed on the microvascular endothelial cell of the blood-air and the blood-brain barrier may explain NiV preferential tropism for small blood vessels of the lung and brain.

  12. A Combined Experimental and Computational Approach to Subject-Specific Analysis of Knee Joint Laxity

    Science.gov (United States)

    Harris, Michael D.; Cyr, Adam J.; Ali, Azhar A.; Fitzpatrick, Clare K.; Rullkoetter, Paul J.; Maletsky, Lorin P.; Shelburne, Kevin B.

    2016-01-01

    Modeling complex knee biomechanics is a continual challenge, which has resulted in many models of varying levels of quality, complexity, and validation. Beyond modeling healthy knees, accurately mimicking pathologic knee mechanics, such as after cruciate rupture or meniscectomy, is difficult. Experimental tests of knee laxity can provide important information about ligament engagement and overall contributions to knee stability for development of subject-specific models to accurately simulate knee motion and loading. Our objective was to provide combined experimental tests and finite-element (FE) models of natural knee laxity that are subject-specific, have one-to-one experiment to model calibration, simulate ligament engagement in agreement with literature, and are adaptable for a variety of biomechanical investigations (e.g., cartilage contact, ligament strain, in vivo kinematics). Calibration involved perturbing ligament stiffness, initial ligament strain, and attachment location until model-predicted kinematics and ligament engagement matched experimental reports. Errors between model-predicted and experimental kinematics averaged ligaments agreed with literature descriptions. These results demonstrate the ability of our constraint models to be customized for multiple individuals and simultaneously call attention to the need to verify that ligament engagement is in good general agreement with literature. To facilitate further investigations of subject-specific or population based knee joint biomechanics, data collected during the experimental and modeling phases of this study are available for download by the research community. PMID:27306137

  13. Chicken line-dependent mortality after experimental infection with three type IIxIII recombinant Toxoplasma gondii clones.

    Science.gov (United States)

    Schares, G; Herrmann, D C; Maksimov, P; Matzkeit, B; Conraths, F J; Moré, G; Preisinger, R; Weigend, S

    2017-09-01

    Three genetically different clones of Toxoplasma gondii, also different in mouse virulence, were studied by experimental infection in chickens. For the experiments, four chicken lines were used, which differed in phylogenetic origin and performance level: two white egg layer lines, one with high laying performance (WLA), one with low (R11) and two brown layer lines, also displaying high (BLA) and low (L68) egg number. Chickens were intraperitoneally infected with three different T. gondii isolates representing type IIxIII recombinant clones, i.e. showing both, type II- and type III-specific alleles. These clones (K119/2 2C10, B136/1 B6H6, K119/2 A7) had exhibited virulence differences in a mouse model. In chickens, a significantly higher mortality was observed in white layer lines, but not in brown layer lines, suggesting that differences in the phylogenetic background may influence the susceptibility of chickens for toxoplasmosis. In addition, antibody (IgY) levels varied in surviving chickens at 31 days post infection. While low to intermediate antibody levels were observed in white layers, intermediate to high levels were measured in brown layers. Infection with a T. gondii clone showing low chicken virulence resulted in higher antibody levels in all chicken lines compared to infection with T. gondii clones of intermediate or high chicken virulence. This was in agreement with the parasite load as determined by real-time PCR. Overall, results show that progeny resulting from natural sexual recombination of T. gondii clonal lineages, may differ in their virulence for mice and chickens. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. An immunohistochemical study of Flexibacter psychrophilus infection in experimentally and naturally infected rainbow trout (Oncorhynchus mykiss) fry

    DEFF Research Database (Denmark)

    Evensen, O.; Lorenzen, Ellen

    1996-01-01

    An immunohistochemical method is described for the detection of Flexibacter psychrophilus in formalin-fixed, parafiin-wax-embedded fry of rainbow trout. Rabbit antiserum as well as rainbow trout hyperimmune serum were used in the study. The distribution and tissue localization of the bacterium wa...... are typically found during the chronic stage of the disease....... and experimentally infected fry showed that there was a localization of bacteria in the monocyte-macrophage system, in skin lesions, and in the retina and the choroid gland of the eye. The dermal changes included superficial or deep ulcers extending to the subcutaneous tissue or the musculature accompanied...... by inflammatory cell infiltrates in which polymorphonuclear inflammatory cells were shown to contain the bacterium in the cytoplasm by immunostaining. The eye changes were likewise a common finding in chronic cases with severe inflammatory changes in the retina and with numerous bacteria in inflammatory (mainly...

  15. Experimental analysis of specification language diversity impact on NPP software diversity

    International Nuclear Information System (INIS)

    Yoo, Chang Sik

    1999-02-01

    In order to increase computer system reliability, software fault tolerance methods have been adopted to some safety critical systems including NPP. Prevention of software common mode failure is very crucial problem in software fault tolerance, but the effective method for this problem is not found yet. In our research, to find out an effective method for prevention of software common mode failure, the impact of specification language diversity on NPP software diversity was examined experimentally. Three specification languages were used to compose three requirements specifications, and programmers made twelve product codes from the specifications. From the product codes analysis, using fault diversity criteria, we concluded that diverse specification language method would enhance program diversity through diversification of requirements specification imperfections

  16. Epidemiology of pathogen-specific respiratory infections among three US populations.

    Directory of Open Access Journals (Sweden)

    Jennifer M Radin

    Full Text Available Diagnostic tests for respiratory infections can be costly and time-consuming. Improved characterization of specific respiratory pathogens by identifying frequent signs, symptoms and demographic characteristics, along with improving our understanding of coinfection rates and seasonality, may improve treatment and prevention measures.Febrile respiratory illness (FRI and severe acute respiratory infection (SARI surveillance was conducted from October 2011 through March 2013 among three US populations: civilians near the US-Mexico border, Department of Defense (DoD beneficiaries, and military recruits. Clinical and demographic questionnaire data and respiratory swabs were collected from participants, tested by PCR for nine different respiratory pathogens and summarized. Age stratified characteristics of civilians positive for influenza and recruits positive for rhinovirus were compared to other and no/unknown pathogen. Seasonality and coinfection rates were also described.A total of 1444 patients met the FRI or SARI case definition and were enrolled in this study. Influenza signs and symptoms varied across age groups of civilians. Recruits with rhinovirus had higher percentages of pneumonia, cough, shortness of breath, congestion, cough, less fever and longer time to seeking care and were more likely to be male compared to those in the no/unknown pathogen group. Coinfections were found in 6% of all FRI/SARI cases tested and were most frequently seen among children and with rhinovirus infections. Clear seasonal trends were identified for influenza, rhinovirus, and respiratory syncytial virus.The age-stratified clinical characteristics associated with influenza suggest that age-specific case definitions may improve influenza surveillance and identification. Improving identification of rhinoviruses, the most frequent respiratory infection among recruits, may be useful for separating out contagious individuals, especially when larger outbreaks occur

  17. Experimental Infection with Sporulated Oocysts of Eimeria maxima (Apicomplexa: Eimeriidae) in Broiler

    Science.gov (United States)

    Brito, Luciana da S.; Pereira, Elder N.; da Silva, Augusta A.; Bentivóglio Costa Silva, Vinícius; Freitas, Fagner L. da C.

    2014-01-01

    Through this study we assessed the metabolic and pathological changes in broilers experimentally infected with oocysts of Eimeria maxima. To perform the experiment, we used 150 broiler strain cooB males, with ten days of age, were randomized according to weight and randomly assigned to two experimental groups: the control group was inoculated with 0.5 mL of distilled water; the infected group inoculated with 0.5 mL of solution containing 5 × 104 sporulated oocysts of Eimeria maxima. The live performance was evaluated on day 0 (day of inoculation), 5°, 10°, 15°, 25°, and 35° dpi, being slaughtered by cervical dislocation, fifteen birds/group. Although the sum in meat production was higher in the control group, the weight of the heart and gizzard of the experimental animals showed no significant difference, while the liver had difference on day 5°, 15°, and 35° dpi. The pathologic evaluation showed congested mucosa and presence of large amounts of mucus at 6 dpi. Therefore, it is concluded that the dose of 5 × 104  E. maxima inoculated in the experimental group was enough to cause harm to the animal organism. PMID:26464925

  18. Antigen-Specific IP-10 Release Is a Sensitive Biomarker of Mycobacterium bovis Infection in Cattle.

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    Sven D C Parsons

    Full Text Available The most widely used ante-mortem diagnostic tests for tuberculosis in cattle are the tuberculin skin test and the interferon-gamma (IFN-γ release assay, both of which measure cell-mediated immune responses to Mycobacterium bovis infection. However, limitations in the performance of these tests results in a failure to identify all infected animals. In attempting to increase the range of diagnostic tests for tuberculosis, measurement of the cytokine IP-10 in antigen-stimulated blood has previously been shown to improve the detection of M. tuberculosis and M. bovis infection, in humans and African buffaloes (Syncerus caffer, respectively. In the present study, 60 cattle were identified by the single intradermal comparative tuberculin test as tuberculosis reactors (n = 24 or non-reactors (n = 36 and the release of IFN-γ and IP-10 in antigen-stimulated whole blood from these animals was measured using bovine specific ELISAs. There was a strong correlation between IP-10 and IFN-γ production in these samples. Moreover, measurement of the differential release of IP-10 in response to stimulation with M. bovis purified protein derivative (PPD and M. avium PPD distinguished between reactor and non-reactor cattle with a sensitivity of 100% (95% CI, 86%-100% and a specificity of 97% (95% CI, 85%-100%. These results suggest that IP-10 might prove valuable as a diagnostic biomarker of M. bovis infection in cattle.

  19. Genotype-Specific Concordance of Chlamydia trachomatis Genital Infection Within Heterosexual Partnerships.

    Science.gov (United States)

    Schillinger, Julia A; Katz, Barry P; Markowitz, Lauri E; Braslins, Phillip G; Shrier, Lydia A; Madico, Guillermo; Van Der Pol, Barbara; Orr, Donald P; Rice, Peter A; Batteiger, Byron E

    2016-12-01

    Sexual transmission rates of Chlamydia trachomatis (Ct) cannot be measured directly; however, the study of concordance of Ct infection in sexual partnerships (dyads) can help to illuminate factors influencing Ct transmission. Heterosexual men and women with Ct infection and their sex partners were enrolled and partner-specific coital and behavioral data collected for the prior 30 days. Microbiological data included Ct culture, and nucleic acid amplification testing (NAAT), quantitative Ct polymerase chain reaction, and ompA genotyping. We measured Ct concordance in dyads and factors (correlates) associated with concordance. One hundred twenty-one women and 125 men formed 128 dyads. Overall, 72.9% of male partners of NAAT-positive women and 68.6% of female partners of NAAT-positive men were Ct-infected. Concordance was more common in dyads with culture-positive members (78.6% of male partners, 77% of female partners). Partners of women and men who were NAAT-positive only had lower concordance (33.3%, 46.4%, respectively). Women in concordant dyads had significantly higher median endocervical quantitative Ct polymerase chain reaction values (3,032) compared with CT-infected women in discordant dyads (1013 inclusion forming units DNA equivalents per mL; P model coitus-specific transmission probabilities.

  20. Molecular diagnosis of Eimeria stiedae in hepatic tissue of experimentally infected rabbits.

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    Hassan, Khaled M; Arafa, Waleed M; Mousa, Waheed M; Shokier, Khaled A M; Shany, Salama A; Aboelhadid, Shawky M

    2016-10-01

    The early detection of Eimeria stiedae in the hepatic tissue of experimentally infected rabbits was investigated using molecular assay. Forty 6-week-old male New Zealand rabbits were divided into two groups. Group A (30 animals) was infected with 2.5 × 10(4) sporulated oocysts of E. stiedae per animal on Day 0 and Group B (10 animals) was used as the uninfected controls. Three animals from Group A and one from Group B were sacrificed at 0, 3, 6, 9, 12, 15, 18, 21, 24 and 27 days post infection (PI). Gross and microscopic post-mortem findings were recorded. Polymerase chain reaction (PCR) of the E. stiedae internal transcribed spacer 1 genomic region was conducted on blood, liver tissue, and feces from the Group A experimentally infected animals. Macroscopically, the liver showed irregular yellowish white nodules pathognomonic to E. stiedae infection beginning on Day 15 PI. Hepatomegaly and ascites were obvious from Day 21-24 PI. The presence of different E. stiedae schizonts and gametocytes in the histopathological sections of the biliary epithelium were evident on Day 15 PI. The E. stiedae PCR was first positive in liver tissues on Day 12 and in fecal samples on Day 18 PI, but the blood samples were negative. In conclusion, the PCR can be used for early diagnosis and control of E. stiedae schizonts before shedding of the oocysts in feces. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Histological assessment of granulomas in natural and experimental Schistosoma mansoni infections using whole slide imaging.

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    Kátia B Amaral

    Full Text Available The pathology of schistosomiasis mansoni, a neglected tropical disease of great clinical and socioeconomic importance, results from the parasite eggs that become trapped in host tissues, particularly in the liver and intestines. Continuous antigenic stimulation from these eggs leads to recruitment of inflammatory cells to the sites of infection with formation of periovular granulomas. These complex structures have variable size and composition and are the most striking histopathological feature of schistosomiasis mansoni. However, evaluation of granulomas by conventional microscopy methods is time-consuming and limited, especially in large-scale studies. Here, we used high resolution Whole Slide Imaging (WSI, which allows fast scanning of entire histological slides, and multiple morphometric evaluations, to assess the granulomatous response elicited in target organs (liver, small and large intestines of two models of schistosomiasis mansoni. One of the advantages of WSI, also termed virtual microscopy, is that it generates images that simultaneously offer high resolution and a wide field of observation. By using a model of natural (Nectomys squamipes, a wild reservoir captured from endemic areas in Brazil and experimental (Swiss mouse infection with Schistosoma mansoni, we provided the first detailed WSI characterization of granulomas and other pathological aspects. WSI and quantitative analyses enabled a fast and reliable assessment of the number, evolutional types, frequency and areas of granulomas and inflammatory infiltrates and revealed that target organs are differentially impacted by inflammatory responses in the natural and experimental infections. Remarkably, high-resolution analysis of individual eosinophils, key cells elicited by this helminthic infection, showed a great difference in eosinophil numbers between the two infections. Moreover, features such as the intestinal egg path and confluent granulomas were uncovered. Thus, WSI may

  2. Validation of a serum neutralization test for detection of antibodies specific to cyprinid herpesvirus 3 in infected common and koi carp (Cyprinus carpio).

    Science.gov (United States)

    Cabon, J; Louboutin, L; Castric, J; Bergmann, S; Bovo, G; Matras, M; Haenen, O; Olesen, N J; Morin, T

    2017-05-01

    Cyprinid herpesvirus 3 (CyHV-3) is the aetiological agent of a serious infective, notifiable disease affecting common carp and varieties. In survivors, infection is generally characterized by a subclinical latency phase with restricted viral replication. The CyHV-3 genome is difficult to detect in such carrier fish that represent a potential source of dissemination if viral reactivation occurs. In this study, the analytical and diagnostic performance of an alternative serum neutralization (SN) method based on the detection of CyHV-3-specific antibodies was assessed using 151 serum or plasma samples from healthy and naturally or experimentally CyHV-3-infected carp. French CyHV-3 isolate 07/108b was neutralized efficiently by sera from carp infected with European, American and Taiwanese CyHV-3 isolates, but no neutralization was observed using sera specific to other aquatic herpesviruses. Diagnostic sensitivity, diagnostic specificity and repeatability of 95.9%, 99.0% and 99.3%, respectively, were obtained, as well as a compliance rate of 89.9% in reproducibility testing. Neutralizing antibodies were steadily detected in infected carp subjected to restrictive or permissive temperature variations over more than 25 months post-infection. The results suggest that this non-lethal diagnostic test could be used in the future to improve the epidemiological surveillance and control of CyHV-3 disease. © 2016 John Wiley & Sons Ltd.

  3. Detection of herpes simplex virus-specific DNA sequences in latently infected mice and in humans.

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    Efstathiou, S; Minson, A C; Field, H J; Anderson, J R; Wildy, P

    1986-02-01

    Herpes simplex virus-specific DNA sequences have been detected by Southern hybridization analysis in both central and peripheral nervous system tissues of latently infected mice. We have detected virus-specific sequences corresponding to the junction fragment but not the genomic termini, an observation first made by Rock and Fraser (Nature [London] 302:523-525, 1983). This "endless" herpes simplex virus DNA is both qualitatively and quantitatively stable in mouse neural tissue analyzed over a 4-month period. In addition, examination of DNA extracted from human trigeminal ganglia has shown herpes simplex virus DNA to be present in an "endless" form similar to that found in the mouse model system. Further restriction enzyme analysis of latently infected mouse brainstem and human trigeminal DNA has shown that this "endless" herpes simplex virus DNA is present in all four isomeric configurations.

  4. Distribution of sialic acid receptors and influenza A virus of avian and swine origin in experimentally infected pigs

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    Viuff Birgitte M

    2011-09-01

    Full Text Available Abstract Background Pigs are considered susceptible to influenza A virus infections from different host origins because earlier studies have shown that they have receptors for both avian (sialic acid-alpha-2,3-terminal saccharides (SA-alpha-2,3 and swine/human (SA-alpha-2,6 influenza viruses in the upper respiratory tract. Furthermore, experimental and natural infections in pigs have been reported with influenza A virus from avian and human sources. Methods This study investigated the receptor distribution in the entire respiratory tract of pigs using specific lectins Maackia Amurensis (MAA I, and II, and Sambucus Nigra (SNA. Furthermore, the predilection sites of swine influenza virus (SIV subtypes H1N1 and H1N2 as well as avian influenza virus (AIV subtype H4N6 were investigated in the respiratory tract of experimentally infected pigs using immunohistochemical methods. Results SIV antigen was widely distributed in bronchi, but was also present in epithelial cells of the nose, trachea, bronchioles, and alveolar type I and II epithelial cells in severely affected animals. AIV was found in the lower respiratory tract, especially in alveolar type II epithelial cells and occasionally in bronchiolar epithelial cells. SA-alpha-2,6 was the predominant receptor in all areas of the respiratory tract with an average of 80-100% lining at the epithelial cells. On the contrary, the SA-alpha-2,3 was not present (0% at epithelial cells of nose, trachea, and most bronchi, but was found in small amounts in bronchioles, and in alveoli reaching an average of 20-40% at the epithelial cells. Interestingly, the receptor expression of both SA-alpha-2,3 and 2,6 was markedly diminished in influenza infected areas compared to non-infected areas. Conclusions A difference in predilection sites between SIV and AIV virus was found, and this difference was in accordance with the distribution of the SA-alpha-2,6 and SA-alpha-2,3 receptor, respectively. The results indicated

  5. Development of a Sensitive and Specific Antigen-Detection System for Strongyloides Stercoralis and Hookworm Infections

    Science.gov (United States)

    1997-06-01

    difficult to specifically identify, and failure to implement the correct antibiotic therapy in a timely fashion can result in the onset of acute symptoms...compromised patients are particularly at risk. Treatment is similar to hookworms. Treatment of nematode infection is fairly standard with therapies using...caninum eggs harvested by floatation in ZnSO 4 solution were similarly processed for PAGE fractionation except that eggs were not homogenized. Figures 13a

  6. Experimental in vitro and in vivo systems for studying the innate immune response during dengue virus infections.

    Science.gov (United States)

    Kitab, Bouchra; Kohara, Michinori; Tsukiyama-Kohara, Kyoko

    2018-03-08

    Dengue is the most prevalent arboviral disease in humans and leads to significant morbidity and socioeconomic burden in tropical and subtropical areas. Dengue is caused by infection with any of the four closely related serotypes of dengue virus (DENV1-4) and usually manifests as a mild febrile illness, but may develop into fatal dengue hemorrhagic fever and shock syndrome. There are no specific antiviral therapies against dengue because understanding of DENV biology is limited. A tetravalent chimeric dengue vaccine, Dengvaxia, has finally been licensed for use, but its efficacy was significantly lower against DENV-2 infections and in dengue-naïve individuals. The identification of mechanisms underlying the interactions between DENV and immune responses will help to determine efficient therapeutic and preventive options. It has been well established how the innate immune system responds to DENV infection and how DENV overcomes innate antiviral defenses, however further progress in this field remains hampered by the absence of appropriate experimental dengue models. Herein, we review the available in vitro and in vivo approaches to study the innate immune responses to DENV.

  7. Detection and quantification of pestivirus in experimentally infected pregnant ewes and their progeny

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    Juste Ramón A

    2009-11-01

    Full Text Available Abstract Background Border disease virus (BDV causes important reproductive losses, and eradication strategies focus on the identification and removal of persistently infected animals arising after in uterine infection. BDV infection dynamics were studied in 13 ewes experimentally infected with BDV-4 genotype at 3 phases of pregnancy [days 108 (group A, 76 (group B and 55 (group C] by quantification of viral RNA in blood collected on days -1 to parturition using quantitative real-time RT-PCR (qRT-PCR. Viral RNA loads were also measured in blood/foetal fluid and tissue samples from their offspring at lambing (3 foetuses, 7 stillborns, 15 lambs. qRT-PCR results were compared with those obtained by conventional RT-PCR and used to predict persistent infections. Results Viral RNA was detected in the ewes between days 2-15 p.i. The viraemia reached its highest peak between days 6-7 p.i. with a second peak at days 11-12 p.i. qRT-PCR was significantly faster to perform (less than 1 h than conventional RT-PCR and detected BDV RNA in more ewes, being detection more continuous and prolonged in time. The virus was detected in peripheral blood in a higher percentage of lambs than in tissues, where differences in viral genome copies were more marked. Skin and cerebral cortex showed the highest viral RNA loads, and spleen and spinal cord the lowest. High viral RNA loads were observed in several animals in group B and all in group C, infected during middle and early foetal development, respectively, but also in one lamb from group A, infected during late foetal development. Serology and viral genome copy number estimates in blood and tissues were used to establish a quantitative cut-off threshold for transient viraemia. Conclusion Viral RNA quantification showed potential for the discrimination between persistent infections and transient viraemia using single-time point blood sampling and raised questions regarding foetal immune system development and the

  8. HIV-1 Infection Is Associated with Depletion and Functional Impairment of Mycobacterium tuberculosis-Specific CD4 T Cells in Individuals with Latent Tuberculosis Infection.

    Science.gov (United States)

    Day, Cheryl L; Abrahams, Deborah A; Harris, Levelle D; van Rooyen, Michele; Stone, Lynnett; de Kock, Marwou; Hanekom, Willem A

    2017-09-15

    Coinfection with HIV is the single greatest risk factor for reactivation of latent Mycobacterium tuberculosis infection (LTBI) and progression to active tuberculosis disease. HIV-associated dysregulation of adaptive immunity by depletion of CD4 Th cells most likely contributes to loss of immune control of LTBI in HIV-infected individuals, although the precise mechanisms whereby HIV infection impedes successful T cell-mediated control of M. tuberculosis have not been well defined. To further delineate mechanisms whereby HIV impairs protective immunity to M. tuberculosis , we evaluated the frequency, phenotype, and functional capacity of M. tuberculosis -specific CD4 T cells in HIV-infected and HIV-uninfected adults with LTBI. HIV infection was associated with a lower total frequency of cytokine-producing M. tuberculosis -specific CD4 T cells, and preferential depletion of a discrete subset of M. tuberculosis -specific IFN-γ + IL-2 - TNF-α + CD4 T cells. M. tuberculosis -specific CD4 T cells in HIV-infected individuals expressed significantly higher levels of Ki67, compared with HIV-uninfected individuals, thus indicating recent activation and turnover of these cells in vivo. The ex vivo proliferative capacity of M. tuberculosis -specific CD4 T cells was markedly impaired in HIV-infected individuals, compared with HIV-uninfected individuals. Moreover, HIV infection was associated with increased M. tuberculosis Ag-induced CD4 T cell death ex vivo, indicating a possible mechanism contributing to impaired proliferative capacity of M. tuberculosis -specific CD4 T cells in HIV-infected individuals. These data provide new insights into the parameters of M. tuberculosis -specific CD4 T cell immunity that are impaired in HIV-infected individuals with LTBI, which may contribute to their increased risk of developing active tuberculosis disease. Copyright © 2017 by The American Association of Immunologists, Inc.

  9. Vertebrate host specificity and experimental vectors of Plasmodium (Novyella) kempi sp. n. from the eastern wild turkey in Iowa.

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    Christensen, B M; Barnes, H J; Rowley, W A

    1983-07-01

    Vertebrate host specificity, experimental laboratory vectors, and a description of Plasmodium (Novyella) kempi sp. n. from eastern wild turkeys (Meleagris gallopavo silvestris Vieillot) in Iowa are presented. Plasmodium kempi is infective for domestic turkeys, bobwhites (Colinus virginianus), chukars (Alectoris graeca), guinea fowl (Numida meleagris), peacocks (Pavo cristatus), and canaries (Serinus canaria), produces a transient infection in mallards (Anas platyrhynchos) and domestic geese (Anser anser), but will not infect ring-necked pheasants (Phasianus colchicus), pigeons (Columba livia), Japanese quail (Coturnix coturnix), leghorn white chickens (Gallus gallus), or starlings (Sturnus vulgaris). Oocysts and (or) sporozoites were recovered from 68% (84/124) and 98% (60/61) of the Culex pipiens pipiens and C. tarsalis examined, respectively. Oocysts developed faster and sporozoites invaded the salivary glands sooner in C. tarsalis (6 days) than in C. p. pipiens (7 days). Culex tarsalis transmitted P. kempi more effectively than C. p. pipiens, although both species were capable of transmitting the parasite by natural feeding. Oocysts developed and sporozoites also were produced in C. restuans, but its ability to transmit the parasite was not determined. Aedes aegypti (Rockefeller strain) and A. triseriatus were refractive to P. kempi. Plasmodium kempi produces trophozoites with large refractile globules and fine cytoplasmic extensions, mature schizonts in the form of a condensed fan containing four to eight nuclei (usually 5), and elongate gametocytes with irregular borders. All stages are confined almost exclusively to mature erythrocytes, with no effect on host cell size or position of host cell nucleus. Plasmodium kempi is most similar morphologically to P. (Novyella) hexamerium and P. (Novyella) vaughani. It differs from P. hexamerium in having large refractile globules in trophozoites and immature schizonts, an inability to infect starlings, an absence of

  10. Experimental infection with Brazilian Newcastle disease virus strain in pigeons and chickens

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    Adriano de Oliveira Torres Carrasco

    2016-03-01

    Full Text Available Abstract This study was designed with the goal of adding as much information as possible about the role of pigeons (Columba livia and chickens (Gallus gallus in Newcastle disease virus epidemiology. These species were submitted to direct experimental infection with Newcastle disease virus to evaluate interspecies transmission and virus-host relationships. The results obtained in four experimental models were analyzed by hemagglutination inhibition and reverse transcriptase polymerase chain reaction for detection of virus shedding. These techniques revealed that both avian species, when previously immunized with a low pathogenic Newcastle disease virus strain (LaSota, developed high antibody titers that significantly reduced virus shedding after infection with a highly pathogenic Newcastle disease virus strain (São Joao do Meriti and that, in chickens, prevent clinical signs. Infected pigeons shed the pathogenic strain, which was not detected in sentinel chickens or control birds. When the presence of Newcastle disease virus was analyzed in tissue samples by RT-PCR, in both species, the virus was most frequently found in the spleen. The vaccination regimen can prevent clinical disease in chickens and reduce viral shedding by chickens or pigeons. Biosecurity measures associated with vaccination programs are crucial to maintain a virulent Newcastle disease virus-free status in industrial poultry in Brazil.

  11. Fasciola hepatica: comparative metacercarial productions in experimentally-infected Galba truncatula and Pseudosuccinea columella

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    Vignoles Philippe

    2015-01-01

    Full Text Available As large numbers of metacercariae of Fasciola hepatica are necessary for research, experimental infections of Galba truncatula and Pseudosuccinea columella with this digenean were carried out to determine the better intermediate host for metacercarial production and, consequently, the most profitable snail for decreasing the cost price of these larvae. Pre-adult snails (4 mm in shell height originating from two populations per lymnaeid species were individually exposed to two or five miracidia, raised at 23 °C and followed for cercarial shedding up to their death. Compared to values noted in G. truncatula, the survival of P. columella on day 30 post-exposure was significantly greater, while the prevalence of F. hepatica infection was significantly lower. In the four P. columella groups, metacercarial production was significantly greater than that noted in the four groups of G. truncatula (347–453 per cercariae-shedding snail versus 163–275, respectively. Apart from one population of G. truncatula, the use of five miracidia per snail at exposure significantly increased the prevalence of F. hepatica in P. columella and the other population of G. truncatula, whereas it did not have any clear effect on the mean number of metacercariae. The use of P. columella for experimental infections with F. hepatica resulted in significantly higher metacercarial production than that noted with G. truncatula, in spite of a lower prevalence for the former lymnaeid. This finding allows for a significant decrease in the cost price of these larvae for commercial production.

  12. Pathology, clinical signs, and tissue distribution of Toxoplasma gondii in experimentally infected reindeer (Rangifer tarandus

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    Émilie Bouchard

    2017-12-01

    Full Text Available Toxoplasma gondii is a zoonotic parasite found in vertebrates worldwide for which felids serve as definitive hosts. Despite low densities of felids in northern Canada, Inuit people in some regions show unexpectedly high levels of exposure, possibly through handling and consumption of Arctic wildlife. Free-ranging caribou (Rangifer tarandus are widely harvested for food across the Canadian North, show evidence of seroexposure to T. gondii, and are currently declining in numbers throughout the Arctic. We experimentally infected three captive reindeer (conspecific with caribou with 1000, 5000 or 10,000 oocysts of T. gondii via stomach intubation to assess clinical signs of infection, pathology, and tissue distribution. An unexposed reindeer served as a negative control. Signs of stress, aggression, and depression were noted for the first two weeks following infection. By 4 weeks post infection, all infected reindeer were positive on a modified agglutination test at the highest titer tested (1:200 for antibodies to T. gondii. At 20 weeks post infection, no gross abnormalities were observed on necropsy. Following histopathology and immunohistochemistry, tissue cysts were visualized in the reindeer given the highest and lowest dose of oocysts. Focal pleuritis and alveolitis were associated with respiratory problems in reindeer given the middle dose. DNA of T. gondii was detected following traditional DNA extraction and conventional PCR on 25 mg samples from 17/33 muscles and organs, and by magnetic capture DNA extraction from 100 g samples from all 26 tissues examined. This research demonstrated that reindeer/caribou can serve as intermediate hosts for T. gondii, and that the parasite may be associated with health effects in wildlife. The presence of T. gondii in all tissues tested, many of which are commonly consumed raw, smoked, or dried in northern communities, suggests that caribou may serve as a source of human exposure to T

  13. Experimental Infection and Detection of Necrotizing Hepatopancreatitis Bacterium in the American Lobster Homarus americanus

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    Luz A. Avila-Villa

    2012-01-01

    Full Text Available Necrotizing hepatopancreatitis bacterium (NHPB is an obligated intracellular bacteria causing severe hepatopancreatic damages and mass mortalities in penaeid shrimp. The worldwide distribution of penaeid shrimp as alien species threatens the life cycle of other crustacean species. The aim of the experiment was to evaluate the possibility of experimentally infecting the American lobster (Homarus americanus with NHPB extracted from shrimp hepatopancreas. Homogenates from infected shrimp were fed by force to lobsters. Other group of lobsters was fed with homogenates of NHPB-free hepatopancreas. After the 15th day from initial inoculation, the presence of NHPB was detected by polymerase chain reaction in feces and hepatopancreas from lobsters inoculated with infected homogenates. Necrotized spots were observed in the surface of lobster hepatopancreas. In contrast, lobsters fed on NHPB-free homogenates resulted negative for NHPB. Evidence suggests the plasticity of NHPB which can infect crustacean from different species and inhabiting diverse latitudes. Considering the results, the American lobster could be a good candidate to maintain available NHPB in vivo.

  14. Experimental Infection and Detection of Necrotizing Hepatopancreatitis Bacterium in the American Lobster Homarus americanus

    Science.gov (United States)

    Avila-Villa, Luz A.; Gollas-Galván, Teresa; Martínez-Porchas, Marcel; Mendoza-Cano, Fernando; Hernández-López, Jorge

    2012-01-01

    Necrotizing hepatopancreatitis bacterium (NHPB) is an obligated intracellular bacteria causing severe hepatopancreatic damages and mass mortalities in penaeid shrimp. The worldwide distribution of penaeid shrimp as alien species threatens the life cycle of other crustacean species. The aim of the experiment was to evaluate the possibility of experimentally infecting the American lobster (Homarus americanus) with NHPB extracted from shrimp hepatopancreas. Homogenates from infected shrimp were fed by force to lobsters. Other group of lobsters was fed with homogenates of NHPB-free hepatopancreas. After the 15th day from initial inoculation, the presence of NHPB was detected by polymerase chain reaction in feces and hepatopancreas from lobsters inoculated with infected homogenates. Necrotized spots were observed in the surface of lobster hepatopancreas. In contrast, lobsters fed on NHPB-free homogenates resulted negative for NHPB. Evidence suggests the plasticity of NHPB which can infect crustacean from different species and inhabiting diverse latitudes. Considering the results, the American lobster could be a good candidate to maintain available NHPB in vivo. PMID:22645497

  15. Respiratory disease in ball pythons (Python regius) experimentally infected with ball python nidovirus.

    Science.gov (United States)

    Hoon-Hanks, Laura L; Layton, Marylee L; Ossiboff, Robert J; Parker, John S L; Dubovi, Edward J; Stenglein, Mark D

    2018-04-01

    Circumstantial evidence has linked a new group of nidoviruses with respiratory disease in pythons, lizards, and cattle. We conducted experimental infections in ball pythons (Python regius) to test the hypothesis that ball python nidovirus (BPNV) infection results in respiratory disease. Three ball pythons were inoculated orally and intratracheally with cell culture isolated BPNV and two were sham inoculated. Antemortem choanal, oroesophageal, and cloacal swabs and postmortem tissues of infected snakes were positive for viral RNA, protein, and infectious virus by qRT-PCR, immunohistochemistry, western blot and virus isolation. Clinical signs included oral mucosal reddening, abundant mucus secretions, open-mouthed breathing, and anorexia. Histologic lesions included chronic-active mucinous rhinitis, stomatitis, tracheitis, esophagitis and proliferative interstitial pneumonia. Control snakes remained negative and free of clinical signs throughout the experiment. Our findings establish a causal relationship between nidovirus infection and respiratory disease in ball pythons and shed light on disease progression and transmission. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  16. Effect of wide spectrum anti-helminthic drugs upon Schistosoma mansoni experimentally infected mice

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    PANCERA Christiane Finardi

    1997-01-01

    Full Text Available Mebendazole, albendazole, levamisole and thiabendazole are well known as active drugs against several nematode species, and against cestodes as well, when the first two drugs are considered. None of the drugs have proven activity, however, against trematodes. We tested the effect of these drugs on the fecal shedding of schistosome eggs and the recovering of adult schistosomes, after portal perfusion in Schistosoma mansoni experimentally infected mice. Balb/c mice infected with 80 S. mansoni cercariae were divided into three groups, each in turn subdivided into four other groups, for each tested drug. The first group was treated with each one of the studied drugs 25 days after S. mansoni infection; the second group was submitted to treatment with each one of the drugs 60 days after infection. Finally, the third group, considered as control, received no treatment. No effect upon fecal shedding of S. mansoni eggs and recovering of schistosomes after portal perfusion was observed when mice were treated with either mebendazole or albendazole. Mice treated with either levamisole or thiabendazole, on the other hand, showed a significant reduction in the recovering of adult schistosomes after portal perfusion, mainly when both drugs were given during the schistosomula evolution period, i.e., 25 days after cercariae penetration, probably due to unspecific immunomodulation

  17. Experimental study of European bat lyssavirus type-2 infection in Daubenton's bats (Myotis daubentonii).

    Science.gov (United States)

    Johnson, Nicholas; Vos, Ad; Neubert, Larissa; Freuling, Conrad; Mansfield, Karen L; Kaipf, Ingrid; Denzinger, Annette; Hicks, Dan; Núñez, Alex; Franka, Richard; Rupprecht, Charles E; Müller, Thomas; Fooks, Anthony R

    2008-11-01

    European bat lyssavirus type 2 (EBLV-2) can be transmitted from Daubenton's bats to humans and cause rabies. EBLV-2 has been repeatedly isolated from Daubenton's bats in the UK but appears to be present at a low level within the native bat population. This has prompted us to investigate the disease in its natural host under experimental conditions, to assess its virulence, dissemination and likely means of transmission between insectivorous bats. With the exception of direct intracranial inoculation, only one of seven Daubenton's bats inoculated by subdermal inoculation became infected with EBLV-2. Both intramuscular and intranasal inoculation failed to infect the bats. No animal inoculated with EBLV-2 seroconverted during the study period. During infection, virus excretion in saliva (both viral RNA and live virus) was confirmed up to 3 days before the development of rabies. Disease was manifested as a gradual loss of weight prior to the development of paralysis and then death. The highest levels of virus were measured in the brain, with much lower levels of viral genomic RNA detected in the tongue, salivary glands, kidney, lung and heart. These observations are similar to those made in naturally infected Daubenton's bats and this is the first documented report of isolation of EBLV-2 in bat saliva. We conclude that EBLV-2 is most likely transmitted in saliva by a shallow bite.

  18. E-NTPDase and E-ADA activities in rats experimental infected by Cryptococcus neoformans.

    Science.gov (United States)

    de Azevedo, Maria Isabel; Ferreiro, Laerte; Da Silva, Aleksandro S; Tonin, Alexandre A; Ruchel, Jader B; Rezer, João F P; França, Raqueli T; Zimmermann, Carine E P; Leal, Daniela B R; Duarte, Marta M M F; Lopes, Sonia T A; Flores, Mariana M; Fighera, Rafael; Santurio, Janio M

    2014-11-07

    Cryptococcus neoformans, the etiological agent of cryptococcosis, is an opportunistic fungal pathogen of immunocompromised individuals. The aim of this study was to evaluate the activities of E-NTPDase and E-ADA in rats experimentally infected by C. neoformans var. grubii. Adult rats (35) were divided in two groups: 18 for the control group (uninfected) (A), and 17 for the infected group (B). Each group was separated into three sub-groups (A1, A2, A3-B1, B2, B3), and samples were collected on 10, 20, and 30 days post-infection (PI). Leukocyte counts, IFN-γ, TNF-α, IgM, IgG levels, and E-NTPDase and E-ADA activities were analyzed. It was possible to observe that IgG and IgM seric levels of infected rats were significantly elevated (PADA activity had a significant reduction (PADA activity in lymphocytes increased significantly (PADA), concomitantly with an inflammatory response (increased levels of cytokines and immunoglobulins) associated with inflammatory infiltrates and histological lesions in the lung. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Toxoplasma gondii infection specifically increases the levels of key host microRNAs.

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    Gusti M Zeiner

    2010-01-01

    Full Text Available The apicomplexan parasite Toxoplasma gondii can infect and replicate in virtually any nucleated cell in many species of warm-blooded animals; thus, it has evolved the ability to exploit well-conserved biological processes common to its diverse hosts. Here we have investigated whether Toxoplasma modulates the levels of host microRNAs (miRNAs during infection.Using microarray profiling and a combination of conventional molecular approaches we report that Toxoplasma specifically modulates the expression of important host microRNAs during infection. We show that both the primary transcripts for miR-17 approximately 92 and miR-106b approximately 25 and the pivotal miRNAs that are derived from miR-17 approximately 92 display increased abundance in Toxoplasma-infected primary human cells; a Toxoplasma-dependent up-regulation of the miR-17 approximately 92 promoter is at least partly responsible for this increase. The abundance of mature miR-17 family members, which are derived from these two miRNA clusters, remains unchanged in host cells infected with the closely related apicomplexan Neospora caninum; thus, the Toxoplasma-induced increase in their abundance is a highly directed process rather than a general host response to infection.Altered levels of miR-17 approximately 92 and miR-106b approximately 25 are known to play crucial roles in mammalian cell regulation and have been implicated in numerous hyperproliferative diseases although the mechanisms driving their altered expression are unknown. Hence, in addition to the implications of these findings on the host-pathogen interaction, Toxoplasma may represent a powerful probe for understanding the normal mechanisms that regulate the levels of key host miRNAs.

  20. SCAR marker specific to detect Magnaporthe grisea infecting finger millets (Eleusine coracana).

    Science.gov (United States)

    Gnanasing Jesumaharaja, L; Manikandan, R; Raguchander, T

    2016-09-01

    To determine the molecular variability and develop specific Sequence Characterized Amplified Region (SCAR) marker for the detection of Magnaporthe grisea causing blast disease in finger millet. Random amplified polymorphic DNA (RAPD) was performed with 14 isolates of M. grisea using 20 random primers. SCAR marker was developed for accurate and specific detection of M. grisea infecting only finger millets. The genetic similarity coefficient within each group and variation between the groups was observed. Among the primers, OPF-08 generated a RAPD polymorphic profile that showed common fragment of 478 bp in all the isolates. This fragment was cloned and sequenced. SCAR primers, Mg-SCAR-FP and Mg-SCAR-RP, were designed using sequence of the cloned product. The specificity of the SCAR primers was evaluated using purified DNA from M. grisea isolates from finger millets and other pathogens viz., Pyricularia oryzae, Colletotrichum gloeosporioides, Colletotrichum falcatum and Colletotrichum capcisi infecting different crops. The SCAR primers amplified only specific 460 bp fragment from DNA of M. grisea isolates and this fragment was not amplified in other pathogens tested. SCAR primers distinguish blast disease of finger millet from rice as there is no amplification in the rice blast pathogen. PCR-based SCAR marker is a convenient tool for specific and rapid detection of M. grisea in finger millets. Genetic diversity in fungal population helps in developing a suitable SCAR marker to identify the blast pathogen at the early stage of infection. © 2016 The Society for Applied Microbiology.

  1. Host specific glycans are correlated with susceptibility to infection by lagoviruses, but not with their virulence.

    Science.gov (United States)

    Lopes, Ana M; Breiman, Adrien; Lora, Mónica; Le Moullac-Vaidye, Béatrice; Galanina, Oxana; Nyström, Kristina; Marchandeau, Stephane; Le Gall-Reculé, Ghislaine; Strive, Tanja; Neimanis, Aleksija; Bovin, Nicolai V; Ruvoën-Clouet, Nathalie; Esteves, Pedro J; Abrantes, Joana; Le Pendu, Jacques

    2017-11-29

    The rabbit hemorrhagic disease virus (RHDV) and the European brown hare syndrome virus (EBHSV) are two lagoviruses from the family Caliciviridae that cause fatal diseases in two leporid genera, Oryctolagus and Lepus , respectively. In the last few years, several examples of host jumps of lagoviruses among leporids were recorded. In addition, a new pathogenic genotype of RHDV emerged and many non-pathogenic strains of lagoviruses have been described. The molecular mechanisms behind host shifts and the emergence of virulence are unknown. Since RHDV uses glycans of the histo-blood group antigen type as attachment factors to initiate infection, we studied if glycan specificities of the new pathogenic RHDV genotype, non-pathogenic lagoviruses and EBHSV potentially play a role in determining host range and virulence of lagoviruses. We observed binding to A, B or H antigens of the histo-blood group family for all strains known to primarily infect European rabbits ( Oryctolagus cuniculus ), that have recently been classified as GI strains. Yet, we could not explain the emergence of virulence since similar glycan specificities were found between several pathogenic and non-pathogenic strains. By contrast, EBHSV, recently classified as GII.1, bound to terminal β-linked N-acetylglucosamine residues of O-glycans. Expression of these attachment factors in the upper respiratory and digestive tracts in three lagomorph species ( Oryctolagus cuniculus, Lepus europaeus and Sylvilagus floridanus ) showed species-specific patterns regarding the susceptibility to infection by these viruses, indicating that species-specific glycan expression is likely a major contributor to lagoviruses host specificity and range. IMPORTANCE Lagoviruses constitute a genus of the Caliciviridae family, comprising highly pathogenic viruses, RHDV and EBHSV, which infect rabbits and hares, respectively. Recently, non-pathogenic strains were discovered and new pathogenic strains have emerged. In addition, host

  2. HIV-specific Fc effector function early in infection predicts the development of broadly neutralizing antibodies.

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    Simone I Richardson

    2018-04-01

    Full Text Available While the induction of broadly neutralizing antibodies (bNAbs is a major goal of HIV vaccination strategies, there is mounting evidence to suggest that antibodies with Fc effector function also contribute to protection against HIV infection. Here we investigated Fc effector functionality of HIV-specific IgG plasma antibodies over 3 years of infection in 23 individuals, 13 of whom developed bNAbs. Antibody-dependent cellular phagocytosis (ADCP, complement deposition (ADCD, cellular cytotoxicity (ADCC and cellular trogocytosis (ADCT were detected in almost all individuals with levels of activity increasing over time. At 6 months post-infection, individuals with bNAbs had significantly higher levels of ADCD and ADCT that correlated with antibody binding to C1q and FcγRIIa respectively. In addition, antibodies from individuals with bNAbs showed more IgG subclass diversity to multiple HIV antigens which also correlated with Fc polyfunctionality. Germinal center activity represented by CXCL13 levels and expression of activation-induced cytidine deaminase (AID was found to be associated with neutralization breadth, Fc polyfunctionality and IgG subclass diversity. Overall, multivariate analysis by random forest classification was able to group bNAb individuals with 85% sensitivity and 80% specificity based on the properties of their antibody Fc early in HIV infection. Thus, the Fc effector function profile predicted the development of neutralization breadth in this cohort, suggesting that intrinsic immune factors within the germinal center provide a mechanistic link between the Fc and Fab of HIV-specific antibodies.

  3. HIV-specific Fc effector function early in infection predicts the development of broadly neutralizing antibodies.

    Science.gov (United States)

    Richardson, Simone I; Chung, Amy W; Natarajan, Harini; Mabvakure, Batsirai; Mkhize, Nonhlanhla N; Garrett, Nigel; Abdool Karim, Salim; Moore, Penny L; Ackerman, Margaret E; Alter, Galit; Morris, Lynn

    2018-04-01

    While the induction of broadly neutralizing antibodies (bNAbs) is a major goal of HIV vaccination strategies, there is mounting evidence to suggest that antibodies with Fc effector function also contribute to protection against HIV infection. Here we investigated Fc effector functionality of HIV-specific IgG plasma antibodies over 3 years of infection in 23 individuals, 13 of whom developed bNAbs. Antibody-dependent cellular phagocytosis (ADCP), complement deposition (ADCD), cellular cytotoxicity (ADCC) and cellular trogocytosis (ADCT) were detected in almost all individuals with levels of activity increasing over time. At 6 months post-infection, individuals with bNAbs had significantly higher levels of ADCD and ADCT that correlated with antibody binding to C1q and FcγRIIa respectively. In addition, antibodies from individuals with bNAbs showed more IgG subclass diversity to multiple HIV antigens which also correlated with Fc polyfunctionality. Germinal center activity represented by CXCL13 levels and expression of activation-induced cytidine deaminase (AID) was found to be associated with neutralization breadth, Fc polyfunctionality and IgG subclass diversity. Overall, multivariate analysis by random forest classification was able to group bNAb individuals with 85% sensitivity and 80% specificity based on the properties of their antibody Fc early in HIV infection. Thus, the Fc effector function profile predicted the development of neutralization breadth in this cohort, suggesting that intrinsic immune factors within the germinal center provide a mechanistic link between the Fc and Fab of HIV-specific antibodies.

  4. Experimental infection of South American camelids with bluetongue virus serotype 8.

    Science.gov (United States)

    Schulz, Claudia; Eschbaumer, Michael; Rudolf, Miriam; König, Patricia; Keller, Markus; Bauer, Christian; Gauly, Matthias; Grevelding, Christoph G; Beer, Martin; Hoffmann, Bernd

    2012-01-27

    Bluetongue (BT) is an infectious, non-contagious disease of wild and domestic ruminants. It is caused by bluetongue virus (BTV) and transmitted by Culicoides biting midges. Since 1998, BT has been emerging throughout Europe, threatening not only the naïve ruminant population. Historically, South American camelids (SAC) were considered to be resistant to BT disease. However, recent fatalities related to BTV in captive SAC have raised questions about their role in BTV epidemiology. Data on the susceptibility of SAC to experimental infection with BTV serotype 8 (BTV-8) were collected in an animal experiment. Three alpacas (Vicugna pacos) and three llamas (Lama glama) were experimentally infected with BTV-8. They displayed very mild clinical signs. Seroconversion was first measured 6-8 days after infection (dpi) by ELISA, and neutralising antibodies appeared 10-13 dpi. BTV-8 RNA levels in blood were very low, and quickly cleared after seroconversion. However, spleens collected post-mortem were still positive for BTV RNA, over 71 days after the last detection in blood samples. Virus isolation was only possible from blood samples of two alpacas by inoculation of highly sensitive interferon alpha/beta receptor-deficient (IFNAR(-/-)) mice. An in vitro experiment demonstrated that significantly lower amounts of BTV-8 adsorb to SAC blood cells than to bovine blood cells. Although this experiment showed that SAC are generally susceptible to a BTV-8 infection, it indicates that these species play a negligible role in BTV epidemiology. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Aspects of resistance to experimental infection with Trypanosoma cruzi; Aspectos da resistencia a infecao experimental com Trypanosoma cruzi

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Viviane Liotti

    2010-07-01

    Chagas disease, a zoonosis caused by the protozoan Trypanosoma cruzi, has a wide distribution in Latin America and extends from the southern part of the United States to Argentina. A number of 10 million of infected people is estimated and another 25 million exposed to the risk. Although discovered over a century, Chagas disease is still a serious infection that causes great socioeconomic impact, with no effective treatment at the chronic phase and in which, a lack of scientific knowledge can be observed. The main goal of this work was that obtaining and using consomic strain of mice, the resistance could be investigated. Consomic strains were produced by programmed mating, in which the animals were monitored with DNA polymorphic markers, and one of his chromosomes was replaced by his homologue from another strain. As parental, were used, the inbred strains C57BL/6/J Unib with resistant phenotype (donor) and as receiver, the A/JUnib strain, that has a susceptible phenotype. These models were used to produce five consomic strains: for the chromosomes 7 (CSs7), 11 (CSs11), 14 (CSs14), 17 (CSs17) and 19 (CSs19), described by Passos et al. (2003) as important in controlling infection caused by the Y strain of T. cruzi. In experimental testing, the consomics were inoculated intraperitoneally at doses of 10{sup 1}, 10{sup 2}, 10{sup 3} and 10{sup 4} using as control, animals from both parental lines. In all consomics, resistance was higher than that observed in the susceptible parental. In a second protocol, the consomics were mated with scheduled associations and the progenies were challenged with inocula employing increasing doses of trypomastigotes. The resistance observed in this group was also higher than that observed in the parental with susceptible phenotype. The observed results demonstrate that the use of the consomic strains that were produced order to assess the contribution of each chromosome in the resistance, as well as the effects of association between

  6. Immuno-pathological studies on broiler chicken experimentally infected with Escherichia coli and supplemented with neem (Azadirachta indica leaf extract

    Directory of Open Access Journals (Sweden)

    Vikash Sharma

    2016-07-01

    Full Text Available Aim: The present study was conducted to evaluate the effects of neem leaf extract (NLE supplementation on immunological response and pathology of different lymphoid organs in experimentally Escherichia coli challenged broiler chickens. Materials and Methods: For this study, we procured 192-day-old broiler chicks from local hatchery and divided them into Groups A and Group B containing 96 birds each on the first day. Chicks of Group A were supplemented with 10% NLE in water, whereas chicks of Group B were not supplemented with NLE throughout the experiment. At 7th day of age, chicks of Group A were divided into A1 and A2 and Group B into B1 and B2 with 54 and 42 chicks, respectively, and chicks of Groups A1 and B1 were injected with E. coli O78 at 107 colony-forming units/0.5 ml intraperitoneally. Six chicks from each group were sacrificed at 0, 2, 4, 7, 14, 21, and 28 days post infection; blood was collected and thorough post-mortem examination was conducted. Tissue pieces of spleen and bursa of Fabricius were collected in 10% buffered formalin for histopathological examination. Serum was separated for immunological studies. Result: E. coli specific antibody titer was significantly higher in Group A1 in comparison to Group B1. Delayed-type hypersensitivity response against 2,4 dinirochlorobenzene (DNCB antigen was significantly higher in Group A1 as compared to Group B1. Pathological studies revealed that E. coli infection caused depletion of lymphocytes in bursa of Fabricius and spleen. Severity of lesions in Group A1 was significantly lower in comparison to Group B1. Conclusion: 10% NLE supplementation enhanced the humoral as well as cellular immune responses attributed to its immunomodulatory property in experimentally E. coli infected broiler chicken.

  7. Immuno-pathological studies on broiler chicken experimentally infected with Escherichia coli and supplemented with neem (Azadirachta indica) leaf extract.

    Science.gov (United States)

    Sharma, Vikash; Jakhar, K K; Dahiya, Swati

    2016-07-01

    The present study was conducted to evaluate the effects of neem leaf extract (NLE) supplementation on immunological response and pathology of different lymphoid organs in experimentally Escherichia coli challenged broiler chickens. For this study, we procured 192-day-old broiler chicks from local hatchery and divided them into Groups A and Group B containing 96 birds each on the first day. Chicks of Group A were supplemented with 10% NLE in water, whereas chicks of Group B were not supplemented with NLE throughout the experiment. At 7(th) day of age, chicks of Group A were divided into A1 and A2 and Group B into B1 and B2 with 54 and 42 chicks, respectively, and chicks of Groups A1 and B1 were injected with E. coli O78 at 10(7) colony-forming units/0.5 ml intraperitoneally. Six chicks from each group were sacrificed at 0, 2, 4, 7, 14, 21, and 28 days post infection; blood was collected and thorough post-mortem examination was conducted. Tissue pieces of spleen and bursa of Fabricius were collected in 10% buffered formalin for histopathological examination. Serum was separated for immunological studies. E. coli specific antibody titer was significantly higher in Group A1 in comparison to Group B1. Delayed-type hypersensitivity response against 2,4 dinirochlorobenzene (DNCB) antigen was significantly higher in Group A1 as compared to Group B1. Pathological studies revealed that E. coli infection caused depletion of lymphocytes in bursa of Fabricius and spleen. Severity of lesions in Group A1 was significantly lower in comparison to Group B1. 10% NLE supplementation enhanced the humoral as well as cellular immune responses attributed to its immunomodulatory property in experimentally E. coli infected broiler chicken.

  8. Single multivalent vaccination boosted by trickle larval infection confers protection against experimental lymphatic filariasis

    Science.gov (United States)

    Joseph, SK; Ramaswamy, K

    2013-01-01

    The multivalent vaccine BmHAT, consisting of the Brugia malayi infective larval (L3) antigens heat shock protein12.6 (HSP12.6), abundant larval transcript-2 (ALT-2) and tetraspanin large extra cellular loop (TSP-LEL), was shown to be protective in rodent models from our laboratory. We hypothesize that since these antigens were identified using protective antibodies from immune endemic normal individuals, the multivalent vaccine can be augmented by natural L3 infections providing protection to the vaccinated host. This hypothesis was tested using single dose of DNA and Protein or Protein alone of the BmHAT vaccination in gerbils followed by live trickle L3 infection as booster dose. Vaccine-induced protection in gerbils was determined by worm establishment, micropore chamber assay and by antibody dependant cell cytotoxicity (ADCC) assay. Results were compared with the traditional prime-boost vaccination regimen. Gerbils vaccinated with BmHAT and boosted with L3 trickle infection were protected 51% (BmHAT DNA-Protein) and 48% (BmHAT Protein) respectively. BmHAT vaccination plus L3 trickle booster generated significant titer of antigen-specific IgG antibodies comparable to the traditional prime boost vaccination approach. BmHAT vaccination plus L3 trickle booster also generated antigen-specific cells in the spleen of vaccinated animals and these cells secreted predominantly IFN-γ and IL-4 in response to the vaccine antigens. These studies thus show that single dose of BmHAT multivalent vaccination followed by L3 trickle booster infection can confer significant protection against lymphatic filariasis. PMID:23735679

  9. Single multivalent vaccination boosted by trickle larval infection confers protection against experimental lymphatic filariasis.

    Science.gov (United States)

    Joseph, S K; Ramaswamy, K

    2013-07-18

    The multivalent vaccine BmHAT, consisting of the Brugia malayi infective larval (L3) antigens heat shock protein12.6 (HSP12.6), abundant larval transcript-2 (ALT-2) and tetraspanin large extra cellular loop (TSP-LEL), was shown to be protective in rodent models from our laboratory. We hypothesize that since these antigens were identified using protective antibodies from immune endemic normal individuals, the multivalent vaccine can be augmented by natural L3 infections providing protection to the vaccinated host. This hypothesis was tested using single dose of DNA and protein or protein alone of the BmHAT vaccination in gerbils followed by live trickle L3 infection as booster dose. Vaccine-induced protection in gerbils was determined by worm establishment, micropore chamber assay and by antibody dependant cell cytotoxicity (ADCC) assay. Results were compared with the traditional prime-boost vaccination regimen. Gerbils vaccinated with BmHAT and boosted with L3 trickle infection were protected 51% (BmHAT DNA-protein) and 48% (BmHAT protein) respectively. BmHAT vaccination plus L3 trickle booster generated significant titer of antigen-specific IgG antibodies comparable to the traditional prime boost vaccination approach. BmHAT vaccination plus L3 trickle booster also generated antigen-specific cells in the spleen of vaccinated animals and these cells secreted predominantly IFN-γ and IL-4 in response to the vaccine antigens. These studies thus show that single dose of BmHAT multivalent vaccination followed by L3 trickle booster infection can confer significant protection against lymphatic filariasis. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Effect of dietary supplementation on resistance to experimental infection with Haemonchus contortus in Creole kids.

    Science.gov (United States)

    Bambou, J C; Archimède, H; Arquet, R; Mahieu, M; Alexandre, G; González-Garcia, E; Mandonnet, N

    2011-06-10

    The aim of the present study was to test the effect of dietary supplementation on resistance to experimental infection with Haemonchus contortus in Creole kids. One trial with three replicates involved a total of 154 female kids that were chosen from three successive cohorts of the Creole flock of INRA-Gardel in 2007. The kids were placed into four treatments according to the amount of concentrate they received: G0 (no concentrate and a quality Dichantium spp. hay ad libitum, HAY), G1 (HAY+100g commercial concentrate d(-1)), G2 (HAY+200 g commercial concentrate d(-1)), G3 (HAY+300 g commercial concentrate d(-1)). The G0-G3 groups were infected with a single dose of 10,000 H. contortus third stage larvae (L(3)) at Day 0 (D0). Each infected group was comprised of one half resistant and one half susceptible genetically indexed kids. The average breeding values on egg excretion at 11 months of age were distant of 0.70, 0.65, 0.61 and 0.61 genetic standard deviations in G0, G1, G2 and G3, respectively. The faecal egg count (FEC), packed cell volume (PCV), eosinophilia (EOSI) and dry matter intake (DMI) indices were monitored weekly until 42 days post-infection. Enzyme-linked immunosorbent assay was carried out on serum samples to determine the level of IgA anti-H. contortus L(3) crude extracts and adult excretion/secretion products (ESP). The 10,000 L(3) dose received by the kids induced a severe infection: 8000 eggs per gram at the FEC peak, a PCV less than 15% and mortality. Interestingly, the supplemented animals in G3 showed a higher level of EOSI but a lower level of IgA anti-L3 and IgA anti-ESP than non-supplemented animals (G0). Resistant and susceptible kids had significantly different FEC variations within the groups. Susceptible kids had a 1.6 times higher egg output than resistant kids in G0. This difference was not found in the supplemented groups. The results of this study showed that supplementary feeding improved resistance of Creole kids to H. contortus

  11. Sensitivity and specificity of parallel or serial serological testing for detection of canine Leishmania infection

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    Mauro Maciel de Arruda

    2016-01-01

    Full Text Available In Brazil, human and canine visceral leishmaniasis (CVL caused byLeishmania infantum has undergone urbanisation since 1980, constituting a public health problem, and serological tests are tools of choice for identifying infected dogs. Until recently, the Brazilian zoonoses control program recommended enzyme-linked immunosorbent assays (ELISA and indirect immunofluorescence assays (IFA as the screening and confirmatory methods, respectively, for the detection of canine infection. The purpose of this study was to estimate the accuracy of ELISA and IFA in parallel or serial combinations. The reference standard comprised the results of direct visualisation of parasites in histological sections, immunohistochemical test, or isolation of the parasite in culture. Samples from 98 cases and 1,327 noncases were included. Individually, both tests presented sensitivity of 91.8% and 90.8%, and specificity of 83.4 and 53.4%, for the ELISA and IFA, respectively. When tests were used in parallel combination, sensitivity attained 99.2%, while specificity dropped to 44.8%. When used in serial combination (ELISA followed by IFA, decreased sensitivity (83.3% and increased specificity (92.5% were observed. Serial testing approach improved specificity with moderate loss in sensitivity. This strategy could partially fulfill the needs of public health and dog owners for a more accurate diagnosis of CVL.

  12. Experimental canine distemper infection as a means of demonstrating latent effects of subacute lead intoxication

    Energy Technology Data Exchange (ETDEWEB)

    White, D.J.; McLeod, S.

    1976-01-01

    Observations on the response of the body to experimental infection with distemper virus in dogs previously dosed subacutely with lead have demonstrated a latent effect of lead on several body systems. Effects which indicated a relationship to earlier treatment with lead included evidence for stimulation of haemoglobin synthesis, changes to red blood cells resulting in increased destruction, increased vulnerability of the parenchymatous cells of the liver to damage, reduction in the weight of the skeleton and thyroid, an increase in weight of the thymus and brain and histopathological changes in the thymus. 21 references, 2 figures, 1 table.

  13. Brazilian avian metapneumovirus subtypes A and B: experimental infection of broilers and evaluation of vaccine efficacy

    OpenAIRE

    Márcia B. dos Santos; Matheus C. Martini; Helena L. Ferreira; Luciana H.A. da Silva; Paulo A. Fellipe; Fernando R. Spilki; Clarice W. Arns

    2012-01-01

    Santos M.B., Martini M.C., Ferreira H.L., Silva L.H.A., Fellipe P.A., Spilki F.R. & Arns C.W. 2012. Brazilian avian metapneumovirus subtypes A and B: experimental infection of broilers and evaluation of vaccine efficacy. Pesquisa Veterinaria Brasileira 32(12):1257-1262. Laboratorio de Virologia, Instituto de Biologia, Universidade Estadual de Campinas, Rua Monteiro Lobato s/n, Cx. Postal 6109, Campinas, SP 13083-970, Brazil. E-mail: Avian metapneumovirus (aMPV) is a respirator...

  14. Detection of arboviruses and other micro-organisms in experimentally infected mosquitoes using massively parallel sequencing.

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    Sonja Hall-Mendelin

    Full Text Available Human disease incidence attributed to arbovirus infection is increasing throughout the world, with effective control interventions limited by issues of sustainability, insecticide resistance and the lack of effective vaccines. Several promising control strategies are currently under development, such as the release of mosquitoes trans-infected with virus-blocking Wolbachia bacteria. Implementation of any control program is dependent on effective virus surveillance and a thorough understanding of virus-vector interactions. Massively parallel sequencing has enormous potential for providing comprehensive genomic information that can be used to assess many aspects of arbovirus ecology, as well as to evaluate novel control strategies. To demonstrate proof-of-principle, we analyzed Aedes aegypti or Aedes albopictus experimentally infected with dengue, yellow fever or chikungunya viruses. Random amplification was used to prepare sufficient template for sequencing on the Personal Genome Machine. Viral sequences were present in all infected mosquitoes. In addition, in most cases, we were also able to identify the mosquito species and mosquito micro-organisms, including the bacterial endosymbiont Wolbachia. Importantly, naturally occurring Wolbachia strains could be differentiated from strains that had been trans-infected into the mosquito. The method allowed us to assemble near full-length viral genomes and detect other micro-organisms without prior sequence knowledge, in a single reaction. This is a step toward the application of massively parallel sequencing as an arbovirus surveillance tool. It has the potential to provide insight into virus transmission dynamics, and has applicability to the post-release monitoring of Wolbachia in mosquito populations.

  15. Efficacy of a 60Co irradiated vaccine for experimentally infected calves with dictyocaulus viviparus

    International Nuclear Information System (INIS)

    Zurita, Edgar; Paredes, Julio; Fernandez, Ardey

    1991-01-01

    Dictyocaulus viviparus larvae in non-infected stage (L.1) were cultured in vitro to their infective stage (L.3) and were irradiated with 40 Krad from 6 0 C o and used as a vaccine. The oral experimental vaccine dose was 1000 L.3/animal. Three groups were formed with 8 calves in each one: group No. 1 and group No. 2 were vaccinated at 10 weeks of age. Four weeks later group No. 1 was infected with non-irradiated 60 L.3/Kg. of animal weight 'challenge dose'. After four weeks of post-vaccination group No. 2 was revaccinated and 4 weeks later it was infected with the 'challenge dose' as the previous group. Eight calves constituted group No. 3, four in each group; they were infected with only the challenge dose respectively. Information data on respiratory and cardiac frequency, temperature, weight, and L.1 count/g. of feces were obtained from each animal three times a week. After five weeks of post-challenge all animals were slaughtered to observe anatomopathologic lessions in the heart and lungs; the number of adult Dictyocaulus viviparus present in the respiratory tract were search 't'. Student test was used for the statistical analysis. The weight increment difference between animals of group No. 1 related control group was 7Kg.; and 11.25 Kg/animal in group No. 2 respectively. The percentage of protection confered by the vaccine to the subjects in group No. 1 relative to the respectivecontrol group, was 83.2; that for the group No. 2 was 88.5 per cent. Post-morten examination revealed severe anatomopathologic lessions in the control groups; only few lessions were observed in group No. 1 and practically none in group No. 2

  16. Unveiling the oxidative metabolism of Achatina fulica (Mollusca: Gastropoda) experimentally infected to Angiostrongylus cantonensis (Nematoda: Metastrongylidae).

    Science.gov (United States)

    Tunholi-Alves, Vinícius Menezes; Tunholi, Victor Menezes; Garcia, Juberlan; Mota, Esther Maria; Castro, Rosane Nora; Pontes, Emerson Guedes; Pinheiro, Jairo

    2018-06-01

    For the first time, alterations in the oxidative metabolism of Achatina fulica experimentally infected with different parasite loads of Angiostrongylus cantonensis were determined. For this, the hemolymph activities of lactate dehydrogenase (LDH) and hexokinase and the glucose concentrations in the hemolymph, as well as the polysaccharide reserves in the digestive gland and cephalopedal mass, were assessed. Additionally, the contents of some carboxylic acids in the hemolymph of infected and uninfected snails were determined by high-performance liquid chromatography (HPLC), permitting a better understanding of the alterations related to the host's oxidative metabolism. As the main results, activation of oxidative pathways, such as the glycolytic pathway, was demonstrated in response to the increase in the activity of hexokinase. This tendency was confirmed by the decrease in the contents of glucose in the hemolymph of parasitized snails, indicating that the infection by A. cantonensis alters the host's metabolism, and that these changes are strongly influenced by the parasite load. This metabolic scenario was accompanied by activation of the anaerobic fermentative metabolism, indicated not only by an increase in the activity of (LDH), but also by a reduction of the content of pyruvic acid and accumulation of lactic acid in the hemolymph of parasitized snails. In this circumstance, maintenance of the host's redox balance occurs through activation of the fermentative pathways, and LDH plays a central role in this process. Together, the results indicate that A. cantonensis infection induces activation of the anaerobic metabolism of A. fulica, characterized not only by the accumulation of lactic acid, but also by a reduction in the pyruvic acid and oxalic acid contents in the hemolymph of the infected snails.

  17. Experimental Infection of Rhodnius prolixus (Hemiptera, Triatominae with Mycobacterium leprae Indicates Potential for Leprosy Transmission.

    Directory of Open Access Journals (Sweden)

    Arthur da Silva Neumann

    Full Text Available Leprosy is a chronic dermato-neurological disease caused by infection with Mycobacterium leprae. In 2013 almost 200,000 new cases of leprosy were detected around the world. Since the first symptoms take from years to decades to appear, the total number of asymptomatic patients is impossible to predict. Although leprosy is one of the oldest records of human disease, the mechanisms involved with its transmission and epidemiology are still not completely understood. In the present work, we experimentally investigated the hypothesis that the mosquitoes Aedes aegypti and Culex quinquefasciatus and the hemiptera Rhodnius prolixus act as leprosy vectors. By means of real-time PCR quantification of M. leprae 16SrRNA, we found that M. leprae remained viable inside the digestive tract of Rhodnius prolixus for 20 days after oral infection. In contrast, in the gut of both mosquito species tested, we were not able to detect M. leprae RNA after a similar period of time. Inside the kissing bug Rhodnius prolixus digestive tract, M. leprae was initially restricted to the anterior midgut, but gradually moved towards the hindgut, in a time course reminiscent of the life cycle of Trypanosoma cruzi, a well-known pathogen transmitted by this insect. The maintenance of M. leprae infectivity inside the digestive tract of this kissing bug is further supported by successful mice footpad inoculation with feces collected 20 days after infection. We conclude that Rhodnius prolixus defecate infective M. leprae, justifying the evaluation of the presence of M. leprae among sylvatic and domestic kissing bugs in countries endemic for leprosy.

  18. Experimental Infection of Rhodnius prolixus (Hemiptera, Triatominae) with Mycobacterium leprae Indicates Potential for Leprosy Transmission.

    Science.gov (United States)

    Neumann, Arthur da Silva; Dias, Felipe de Almeida; Ferreira, Jéssica da Silva; Fontes, Amanda Nogueira Brum; Rosa, Patricia Sammarco; Macedo, Rafael Enrique; Oliveira, José Henrique; Teixeira, Raquel Lima de Figueiredo; Pessolani, Maria Cristina Vidal; Moraes, Milton Ozório; Suffys, Philip Noel; Oliveira, Pedro L; Sorgine, Marcos Henrique Ferreira; Lara, Flavio Alves

    2016-01-01

    Leprosy is a chronic dermato-neurological disease caused by infection with Mycobacterium leprae. In 2013 almost 200,000 new cases of leprosy were detected around the world. Since the first symptoms take from years to decades to appear, the total number of asymptomatic patients is impossible to predict. Although leprosy is one of the oldest records of human disease, the mechanisms involved with its transmission and epidemiology are still not completely understood. In the present work, we experimentally investigated the hypothesis that the mosquitoes Aedes aegypti and Culex quinquefasciatus and the hemiptera Rhodnius prolixus act as leprosy vectors. By means of real-time PCR quantification of M. leprae 16SrRNA, we found that M. leprae remained viable inside the digestive tract of Rhodnius prolixus for 20 days after oral infection. In contrast, in the gut of both mosquito species tested, we were not able to detect M. leprae RNA after a similar period of time. Inside the kissing bug Rhodnius prolixus digestive tract, M. leprae was initially restricted to the anterior midgut, but gradually moved towards the hindgut, in a time course reminiscent of the life cycle of Trypanosoma cruzi, a well-known pathogen transmitted by this insect. The maintenance of M. leprae infectivity inside the digestive tract of this kissing bug is further supported by successful mice footpad inoculation with feces collected 20 days after infection. We conclude that Rhodnius prolixus defecate infective M. leprae, justifying the evaluation of the presence of M. leprae among sylvatic and domestic kissing bugs in countries endemic for leprosy.

  19. Efficacy of one dose vaccination against experimental infection with two Mycoplasma hyopneumoniae strains.

    Science.gov (United States)

    Michiels, Annelies; Arsenakis, Ioannis; Boyen, Filip; Krejci, Roman; Haesebrouck, Freddy; Maes, Dominiek

    2017-08-29

    Mycoplasma hyopneumoniae (M. hyopneumoniae) is the primary agent of enzootic pneumonia in pigs. Pigs are often infected with different M. hyopneumoniae strains. This study assessed the efficacy of vaccination against experimental infection with two genetically different M. hyopneumoniae strains in weaned piglets. At 33 days of age (D0), 45 M. hyopneumoniae-free piglets were randomly assigned to three different groups: 1) negative control group (NCG; n = 5): not vaccinated, not infected, 2) positive control group (PCG; n = 20): not vaccinated, infected, and 3) vaccination group (VG; n = 20): single vaccination with an inactivated whole-cell M. hyopneumoniae vaccine (Hyogen®, Ceva) (D1), infected. The PCG and VG were endotracheally inoculated with 7 × 10 7 CCU in 7 ml of the highly virulent M. hyopneumoniae strain F7.2C (D24) and 7 × 10 7 CCU in 7 ml low virulent strain F1.12A (D25). A respiratory disease score (RDS) was assessed from D24 until D53. At D53 (euthanasia), macroscopic lung lesions (MLL) were scored, log copies of M. hyopneumoniae DNA (qPCR) and IL-1 and IL-6-concentrations (ELISA) on bronchoalveolar lavage fluid were determined. The RDS and MLL at euthanasia were respectively 0, 1.20 and 0.55 (P hyopneumoniae strain as the vaccinated pigs coughed significantly less, and showed significantly less lung lesions compared to the non-vaccinated challenged pigs: the vaccinated animals showed a 52.9% lower RDS and 91.0% lower MLL compared to the PCG. In the bronchoalveolar lavage fluid collected at the necropsy of the vaccinated pigs, a significantly lower amount of M. hyopneumoniae-DNA and a significantly lower IL-1 and IL-6 concentration was found compared to the pigs of the PCG.

  20. Experimental infection of Aphanomyces invadans and susceptibility in seven species of tropical fish

    Directory of Open Access Journals (Sweden)

    Seyedeh F. Afzali

    2015-09-01

    Full Text Available Aim: Epizootic ulcerative syndrome (EUS causes by aquatic oomycete fungus, Aphanomyces invadans is a dangerous fish disease of a wide range of fresh and brackish water, wild and farmed fish throughout the world. The objective of the present study was to determine the susceptibility of a number of tropical fish species to the EUS and compare the severity of infection between experimental groups. Materials and Methods: Snakehead, Channa striata (Bloch, 1793; snakeskin gourami, Trichopodus pectoralis (Regan, 1910; koi carp, Cyprinus carpio (Linnaeus, 1758; broadhead catfish, Clarias macrocephalus (Günther, 1864; goldfish, Carassius auratus (Linnaeus, 1758; climbing perch, Anabas testudineus (Bloch, 1792; and Nile tilapia, Oreochromis niloticus (Linnaeus, 1758 were challenged by intramuscular injection using zoospores of Aphanomyces invadans (NJM9701. The infected fish skins and muscles were examined for EUS histopathological characteristics, and the results on the severity of lesions and mortality were analyzed using SPSS program. Results: All zoospore-injected fish were shown to be susceptible to the EUS infection except Nile tilapia. Although, the general histopathological pattern was similar in the zoospore-injected group, but there were some variation in granulomatous reaction, that is the presence or absence of giant cells, and time of mortality were detected. The result of statistical analysis showed that there was a significant difference between species, (c2=145.11 and p<0.01. Conclusion: Gourami, koi carp, and catfish were demonstrated to be highly susceptible while goldfish and climbing perch were found to be moderately susceptible to the EUS infection. These findings suggested that the cellular response of fish to mycotic infection and granulomatous reaction varied in different fish species, which could not be an indicator of susceptibility or resistant to the EUS itself, although it was shown that the granulation rate and the level of

  1. Age-dependent differences in cytokine and antibody responses after experimental RSV infection in a bovine model

    DEFF Research Database (Denmark)

    Grell, S.N.; Riber, Ulla; Tjørnehøj, Kirsten

    2005-01-01

    Respiratory syncytial virus (RSV) causes severe respiratory disease in both infants and calves. As in humans, bovine RSV (BRSV) infections are most severe in the first 6 months of life. In this study, experimental infection with BRSV was performed in calves aged 1-5, 9-16 or 32-37 weeks. Compared...

  2. Experimental infection of highly pathogenic avian influenza virus H5N1 in black-headed gulls (Chroicocephalus ridibundus)

    NARCIS (Netherlands)

    A. Ramis (Antonio); G. van Amerongen (Geert); M.W.G. van de Bildt (Marco); L.M.E. Leijten (Lonneke); R. Vanderstichel (R.); A.D.M.E. Osterhaus (Albert); T. Kuiken (Thijs)

    2014-01-01

    textabstractHistorically, highly pathogenic avian influenza viruses (HPAIV) rarely resulted in infection or clinical disease in wild birds. However, since 2002, disease and mortality from natural HPAIV H5N1 infection have been observed in wild birds including gulls. We performed an experimental

  3. Comparison of abortion and infection after experimental challenge of pregnant bison and cattle with Brucella abortus strain 2308

    Science.gov (United States)

    A comparative study was conducted using data from naive bison (n=45) and cattle (n=46) from 8 and 6 studies, respectively, in which a standardized Brucella abortus strain 2308 experimental challenge was administered. The incidence of abortion, fetal infection, uterine or mammary infection, or infec...

  4. Transplacental and oral transmission of wild-type bluetongue virus serotype 8 in cattle after experimental infection

    NARCIS (Netherlands)

    Backx, A.; Heutink, C.G.; Rooij, van E.M.A.; Rijn, van P.A.

    2009-01-01

    Potential vertical transmission of wild-type bluetongue virus serotype 8 (BTV-8) in cattle was explored in this experiment. We demonstrated transplacental transmission of wild-type BTV-8 in one calf and oral infection with BTV-8 in another calf. Following the experimental BTV-8 infection of seven

  5. Calculator for the correction of the experimental specific migration for comparison with the legislative limit

    DEFF Research Database (Denmark)

    Petersen, Jens Højslev; Hoekstra, Eddo J.

    The EURL-NRL-FCM Taskforce on the Fourth Amendment of the Plastic Directive 2002/72/EC developed a calculator for the correction of the test results for comparison with the specific migration limit (SML). The calculator calculates the maximum acceptable specific migration under the given experime......The EURL-NRL-FCM Taskforce on the Fourth Amendment of the Plastic Directive 2002/72/EC developed a calculator for the correction of the test results for comparison with the specific migration limit (SML). The calculator calculates the maximum acceptable specific migration under the given...... experimental conditions in food or food stimulant and indicates whether the test result is in compliance with the legislation. This calculator includes the Fat Reduction Factor, the simulant D Reduction Factor and the factor of the difference in surface-to-volume ratio between test and real food contact....

  6. Experimental infection and transmission of Leishmania by Lutzomyia cruzi (Diptera: Psychodidae: Aspects of the ecology of parasite-vector interactions.

    Directory of Open Access Journals (Sweden)

    Everton Falcão de Oliveira

    2017-02-01

    Full Text Available Several parameters should be addressed before incriminating a vector for Leishmania transmission. Those may include its ability to become infected by the same Leishmania species found in humans, the degree of attractiveness for reservoirs and humans and capacity to sustain parasite infection under laboratory conditions. This study evaluated the vectorial capacity of Lutzomyia cruzi for Leishmania infantum and gathered information on its ability to harbor L. amazonensis. Laboratory-reared Lu. cruzi were infected experimentally by feeding them on dogs infected naturally with L. infantum and hamsters infected with L. amazonensis. Sand fly attractiveness to dogs and humans was determined using wild caught insects. The expected daily survival of infected Lu. cruzi, the duration of the gonotrophic cycle, and the extrinsic incubation period were also investigated for both parasites. Vector competence was investigated for both Leishmania species. The mean proportion of female sand flies that fed on hosts was 0.40. For L. infantum and L. amazonensis, Lu. cruzi had experimental infection rates of 10.55% and 41.56%, respectively. The extrinsic incubation period was 3 days for both Leishmania species, regardless of the host. Survival expectancy of females infected with L. infantum and L. amazonensis after completing the gonotrophic cycle was 1.32 and 0.43, respectively. There was no association between L. infantum infection and sand fly longevity, but L. amazonensis-infected flies had significantly greater survival probabilities. Furthermore, egg-laying was significantly detrimental to survival. Lu. cruzi was found to be highly attracted to both dogs and humans. After a bloodmeal on experimentally infected hosts, both parasites were able to survive and develop late-stage infections in Lu. cruzi. However, transmission was demonstrated only for L. amazonensis-infected sand flies. In conclusion, Lu. cruzi fulfilled several of the requirements of vectorial

  7. Experimental infection and transmission of Leishmania by Lutzomyia cruzi (Diptera: Psychodidae): Aspects of the ecology of parasite-vector interactions.

    Science.gov (United States)

    Falcão de Oliveira, Everton; Oshiro, Elisa Teruya; Fernandes, Wagner de Souza; Murat, Paula Guerra; Medeiros, Márcio José de; Souza, Alda Izabel; Oliveira, Alessandra Gutierrez de; Galati, Eunice Aparecida Bianchi

    2017-02-01

    Several parameters should be addressed before incriminating a vector for Leishmania transmission. Those may include its ability to become infected by the same Leishmania species found in humans, the degree of attractiveness for reservoirs and humans and capacity to sustain parasite infection under laboratory conditions. This study evaluated the vectorial capacity of Lutzomyia cruzi for Leishmania infantum and gathered information on its ability to harbor L. amazonensis. Laboratory-reared Lu. cruzi were infected experimentally by feeding them on dogs infected naturally with L. infantum and hamsters infected with L. amazonensis. Sand fly attractiveness to dogs and humans was determined using wild caught insects. The expected daily survival of infected Lu. cruzi, the duration of the gonotrophic cycle, and the extrinsic incubation period were also investigated for both parasites. Vector competence was investigated for both Leishmania species. The mean proportion of female sand flies that fed on hosts was 0.40. For L. infantum and L. amazonensis, Lu. cruzi had experimental infection rates of 10.55% and 41.56%, respectively. The extrinsic incubation period was 3 days for both Leishmania species, regardless of the host. Survival expectancy of females infected with L. infantum and L. amazonensis after completing the gonotrophic cycle was 1.32 and 0.43, respectively. There was no association between L. infantum infection and sand fly longevity, but L. amazonensis-infected flies had significantly greater survival probabilities. Furthermore, egg-laying was significantly detrimental to survival. Lu. cruzi was found to be highly attracted to both dogs and humans. After a bloodmeal on experimentally infected hosts, both parasites were able to survive and develop late-stage infections in Lu. cruzi. However, transmission was demonstrated only for L. amazonensis-infected sand flies. In conclusion, Lu. cruzi fulfilled several of the requirements of vectorial capacity for L. infantum

  8. B-Cell and T-Cell Immune Responses to Experimental Helicobacter pylori Infection in Humans

    Science.gov (United States)

    Nurgalieva, Zhannat Z.; Conner, Margaret E.; Opekun, Antone R.; Zheng, Carl Q.; Elliott, Susan N.; Ernst, Peter B.; Osato, Michael; Estes, Mary K.; Graham, David Y.

    2005-01-01

    The acute antibody and T-cell immune response to Helicobacter pylori infection in humans has not been studied systematically. Serum from H. pylori-naive volunteers challenged with H. pylori and cured after 4 or 12 weeks was tested by enzyme-linked immunosorbent assays for anti-H. pylori-specific immunoglobulin M (IgM) and IgA established using bacterial lysates from homologous (the infecting strain) and heterologous H. pylori. Proteins recognized by IgM antibody were identified by mass spectrometry of immunoreactive bands separated by two-dimensional gel electrophoresis. Mucosal T-cell subsets (CD4, CD8, CD3, and CD30 cells) were assessed by immunohistochemistry. All 18 infected volunteers developed H. pylori-specific IgM responses to both homologous or heterologous H. pylori antigens. H. pylori antigens reacted with IgM antibody at 4 weeks postinfection. IgM Western blotting showed immunoreactivity of postinfection serum samples to multiple H. pylori proteins with molecular weights ranging between 9,000 (9K) to 150K with homologous strains but only a 70K band using heterologous antigens. Two-dimensional electrophoresis demonstrated that production of H. pylori-specific IgM antibodies was elicited by H. pylori flagellins A and B, urease B, ABC transporter binding protein, heat shock protein 70 (DnaK), and alkyl hydroperoxide reductase. Mucosal CD3, CD4, and CD8 T-cell numbers increased following infection. IgM antibody responses were detected to a range of homologous H. pylori antigens 2 to 4 weeks postchallenge. The majority of H. pylori proteins were those involved in motility and colonization and may represent targets for vaccine development. PMID:15845507

  9. Characteristics and specificity of acquired immunologic memory to Mycobacterium tuberculosis infection

    International Nuclear Information System (INIS)

    Orme, I.M.

    1988-01-01

    The results herein show that mice infected with Mycobacterium tuberculosis and then exposed to a protracted course of isoniazid chemotherapy possess a heightened state of acquired resistance to subsequent challenge with the homologous organism. Our results provide the first evidence, moreover, that this resistance is mediated by a long-lived, cyclophosphamide- and irradiation-resistant L3T4+ Lyt-2- lymphocyte capable of giving rise to an accelerated re-emergence of resistance in the animal upon rechallenge. Evidence is also provided to show that triggering of this memory-immune T cell population in the re-challenged host was associated with the rapid emergence of non-specific resistance to secondary bacterial infection; however, the accelerated emergence of this population was only observed if the challenge inoculum consisted of the living organism. The relevance of this latter finding to strategies for vaccine development is discussed

  10. The nutritional status affects the complete blood count of goats experimentally infected with Haemonchus contortus.

    Science.gov (United States)

    Cériac, S; Jayles, C; Arquet, R; Feuillet, D; Félicité, Y; Archimède, H; Bambou, J-C

    2017-11-09

    Gastrointestinal nematode (GIN) remains the most important pathogenic constraint of small ruminant production worldwide. The improvement of the host immune response against GIN though breeding for improved animal resistance, vaccination and nutritional supplementation appear as very promising methods. The objective of this study was to investigate the effect of four nutritional status differing in protein and energy levels (Hay: 5.1 MJ/Kg of dry matter (DM) and 7.6% of crude protein (CP), Ban: 8.3 MJ/Kg of DM and 7.5% of CP, Soy: 7.6 MJ/Kg of DM and 17.3% of CP, BS: 12.7 MJ/Kg of DM and 7.4% of CP) on the haematological disturbances due to Haemonchus contortus infection in Creole kid goats. No significant effect of the nutritional status was observed for faecal egg count (FEC) but the experimental infection induced haematological disturbances whose intensity and lengthening were dependent on the nutritional status. A transient marked regenerative macrocytic hypochromic anaemia as revealed by a decrease of packed cell volume (PCV), red blood cells (RBC) and hemoglobin and an increase of reticulocytes was observed in all infected groups except Hay. In this latter, the anaemia settled until the end of the experiment. Furthermore, H. contortus induced a thrombocytopenia significantly more pronounced in the group under the lowest nutritional status in term of protein (Hay and Ban). A principal component analysis revealed that the variables that discriminated the nutritional status were the average daily gain (ADG) and the PCV, considered as measures of the level of resilience to H. contortus infection. Moreover, the variables that discriminated infected and non-infected animals were mostly related to the biology of RBC (i.e. size and hemoglobin content) and they were correlated with FEC. The severity and the lengthening of the regenerative anaemia and the thrombocytopenia induced by H. contortus have been affected by the nutritional status. The protein enriched

  11. EXPERIMENTAL INFECTION BY Trypanosoma vivax IN GOATS INFECÇÃO EXPERIMENTAL EM CAPRINOS COM Trypanosoma vivax

    Directory of Open Access Journals (Sweden)

    Francisco David Nascimento Sousa

    2008-10-01

    Full Text Available

    Four goats were infected intravenously with 1.0 mL of cattle blood containing about 1.25 x 105 Trypanosoma vivax derived from spontaneous outbreak in cattle at Catolé do Rocha city, Paraíba, Brazil. Other four goats were used as controls. Parasitemia and body temperature were determined daily for 40 days. Animals were weighted each 7 days, and blood samples for blood cells counts were collected each 5 days. It was obtained a sample of liquor from each animal before death; cerebrospinal fluid samples were submitted to biochemical and cytological evaluations, density determination and parasite detection. A positive correlation was found between body temperature and parasitemia in infected animals. These animals presented anemia, leukopenia, hypoglycemia, decreased serum levels of total proteins and cholesterol, and nervous symptoms. Examination of cerebrospinal fluid resulted in decrease of glucose levels and increase in lactate dehydrogenase, cell counts and presence of the parasite. At necropsy it was found pale carcass, generalized infartation of lymphonodes, pulmonary edema, and liquid accumulation of pericardium. Histological changes were characterized by interstitial pneumonia, miocarditis, cardiac fibrosis, meningitis, and encephalitis. All observed changes confirm patogenicity of T. vivax.

    KEY WORDS: Experimental infection, trypanosomiasis, patogenicity.

    Quatro caprinos foram infectados experimentalmente por via intravenosa com 1,0 ml de sangue contendo aproximadamente 1,25 x 105 tripanossomas/ml, utilizando-se um isolado de Trypanosoma vivax de bovinos infectados naturalmente no município de Catolé do Rocha, Paraíba. A parasitemia e a temperatura foram determinadas diariamente durante quarenta dias. A cada cinco dias realizaram-se coletas de sangue para hemograma e análise bioquímica sérica. Antes do

  12. A Cow- and Herd-specific Bio-Economic Model of Intramammary Infections in Dairy Cows

    DEFF Research Database (Denmark)

    Kirkeby, Carsten Thure; Gussmann, Maya Katrin; Græsbøll, Kaare

    Introduction. Mastitis, or intramammary infection (IMI), is one of the most significant diseases in dairy herds worldwide. It is caused by environmental and contagious bacteria. Simulation models have proven useful for evaluating the effect of different control strategies. However, previous...... published models are not cow-specific and therefore not so detailed in the simulation of host-pathogen interactions. If a simulation model is to be used by dairy farmers as a decision-making tool, it needs to be cow-specific because daily management decisions are made on cow level. Furthermore, as IMI......, contagious or mixed), the model should be able to reflect this diversity. Our objective was thus to create a pathogen-, cow- and herd-specific bio-economic simulation model that could simulate multiple pathogens and strains at the same time within a dairy herd. This model should be able to simulate realistic...

  13. Efficacy of sulfonamides and Baycox(®) against Isospora suis in experimental infections of suckling piglets.

    Science.gov (United States)

    Joachim, Anja; Mundt, Hans-Christian

    2011-12-01

    Sulfonamide treatment of piglets against neonatal coccidiosis has frequently been suggested in the literature. In order to evaluate the efficacy of sulfonamides against experimental Isospora suis infections in suckling piglets (oral infection with 1,500 sporulated oocysts of I. suis per piglet on the fourth day of life), two trials were conducted. In trial I, oral sulfadimidine (group Sulfa-Oral) was applied in doses of 100 mg/kg of body weight (BW) 1 day before infection and 75 mg/kg BW daily for the following 5 days, and sulfamethoxypyrimidine (SMP) was applied parenterally in daily doses of 75 mg/kg BW for the same time period. In trial II, SMP was applied parenterally in doses of 75 mg/kg BW (a) from the day of infection daily for 7 days (SMP-Standard), (b) for 2 days starting on the day of infection (SMP-Early), (c) for 3 days starting 2 days post-infection (d.p.i.; SMP-Middle), (d) for 2 days starting 5 d.p.i. (SMP-Late), and (e) every other day from the day of infection until 6 d.p.i. (SMP-Alternating), as well as (f) orally in doses of 75 mg/kg BW from the day of infection for 7 days (SMP-Oral). The sulfonamide-treated groups were compared to a toltrazuril-treated group (single oral treatment with Baycox® 5% suspension, 20 mg/kg BW 2 d.p.i.) and to a water-treated Control group. Each group consisted of seven to nine piglets. The parameters evaluated were oocyst excretion and fecal consistency/diarrhea from 4 to 15 d.p.i. Sulfa-Oral, SMP-Early, and SMP-Late had no significant effect in reduction of oocyst excretion and diarrhea, whereas treatment for 3-7 days with SMP reduced both parasite shedding and diarrhea significantly. Oral treatment with SMP was comparable to parenteral application. Baycox® in a single application had the most pronounced effect and completely suppressed oocyst excretion and diarrhea during the examination period. It could be shown that repeated application of sulfonamides, provided that the appropriate time period after infection

  14. Systemic and mucosal immunization with Candida albicans hsp90 elicits hsp90-specific humoral response in vaginal mucosa which is further enhanced during experimental vaginal candidiasis.

    Science.gov (United States)

    Raska, Milan; Belakova, Jana; Horynova, Milada; Krupka, Michal; Novotny, Jiri; Sebestova, Martina; Weigl, Evzen

    2008-08-01

    The Candida albicans heat shock protein 90 kDa (hsp90-CA) is an important target for protective antibodies in disseminated candidiasis of experimental mice and humans. Hsp90-CA is present in the cell wall of Candida pseudohyphae or hyphae--typical pathogenic morphotypes in both mucosal and systemic Candida infections. However, the potential protective effects of hsp90-CA-specific antibodies in vaginal candidiasis has not yet been reported. In the present study we used various vaccine formulations (recombinant hsp90-CA protein and hsp90-CA-encoding DNA vaccine) and routes of administration (intradermal, intranasal, and intravenous) to induce both hsp90-CA-specific systemic and vaginal mucosa immune responses in experimental BALB/c mice. The results showed that intradermal recombinant hsp90-CA protein priming, followed by intranasal or intradermal recombinant hsp90-CA protein boosting induced significant increases in both serum and vaginal hsp90-CA-specific IgG and IgA antibodies compared to the control group, as well as enhanced hsp90-CA-specific splenocyte responses in vitro. In the intradermally boosted group, subsequent experimental vaginal Candida infection induced additional increases in the hsp90-CA specific IgG isotype, suggesting that Candida has the ability to induce a local hsp90-specific antibody (IgG) response during vulvovaginal candidiasis. Further work is required to elucidate the importance of immunity to highly conserved antigens during infection of the human female reproductive tract where a balance between immunity to and tolerance for commonly antigens such as hsp90 is necessary for the maintenance of fertility.

  15. Pelacakan Secara Imunohistokimiawi Antigen Virus pada Ayam yang Diinfeksi dengan Virus Penyakit Tetelo (IMMUNOHISTOCHEMICAL DETECTION OF VIRAL ANTIGEN IN TISSUE OF CHICKENS EXPERIMENTALLY INFECTED WITH NEWCASTLE DISEASE VIRUS

    Directory of Open Access Journals (Sweden)

    Anak Agung Ayu Mirah Adi

    2013-07-01

    Full Text Available In order to study the distribution of Newcastle disease virus (NDV following infection, chickenswere experimentally infected with visceretropic velogenic NDV isolate. Monoclonal antibodies (mAbsagainst the NDV LaSota vaccine strain were then produced to detect viral antigen in the infectedorgans. The mAbs were firstly tested for their specificity by enzyme linked immunosorbent assay(ELISA using NDV and normal allantoic fluids as antigens. Eight mAbs specific against NDVwere isolated and two mAbs were used for immunodetection of NDV antigen in chicken’s tissues.By immunohistochemistry labeled streptavidin-biotin (LSAB staining NDV–antigen was detectedin paraffin embedded tissues of NDV-infected chickens. NDV antigen was not detected in noninfected chickens. In the infected chickens, high intensity of NDV antigen was detected in thelymphoid tissues, lung and intestine. The NDV antigen with a lesser intensity was detected in thebrain, trachea, liver and myocardium. This study shows that although viscerotropic velogenicNDV isolate can infect almost all organs, the main target of infection are lung, intestine andlymphoids tissues

  16. Experimental Investigation on the Specific Heat of Carbonized Phenolic Resin-Based Ablative Materials

    Science.gov (United States)

    Zhao, Te; Ye, Hong; Zhang, Lisong; Cai, Qilin

    2017-10-01

    As typical phenolic resin-based ablative materials, the high silica/phenolic and carbon/phenolic composites are widely used in aerospace field. The specific heat of the carbonized ablators after ablation is an important thermophysical parameter in the process of heat transfer, but it is rarely reported. In this investigation, the carbonized samples of the high silica/phenolic and carbon/phenolic were obtained through carbonization experiments, and the specific heat of the carbonized samples was determined by a 3D DSC from 150 °C to 970 °C. Structural and compositional characterizations were performed to determine the mass fractions of the fiber and the carbonized product of phenolic which are the two constituents of the carbonized samples, while the specific heat of each constituent was also measured by 3D DSC. The masses of the carbonized samples were reduced when heated to a high temperature in the specific heat measurements, due to the thermal degradation of the carbonized product of phenolic resin in the carbonized samples. The raw experimental specific heat of the two carbonized samples and the carbonized product of phenolic resin was modified according to the quality changes of the carbonized samples presented by TGA results. Based on the mass fraction and the specific heat of each constituent, a weighted average method was adopted to obtain the calculated results of the carbonized samples. Due to the unconsolidated property of the fiber samples which impacts the reliability of the DSC measurement, there is a certain deviation between the experimental and calculated results of the carbonized samples. Considering the similarity of composition and structure, the data of quartz glass and graphite were used to substitute the specific heat of the high silica fiber and carbon fiber, respectively, resulting in better agreements with the experimental ones. Furthermore, the accurate specific heat of the high silica fiber and carbon fiber bundles was obtained by

  17. Dynamics of Pathological and Virological Findings During Experimental Calpox Virus Infection of Common Marmosets (Callithrix jacchus

    Directory of Open Access Journals (Sweden)

    Anne Schmitt

    2017-11-01

    Full Text Available Experimental intranasal infection of marmosets (Callithrix jacchus with calpox virus results in fatal disease. Route and dose used for viral inoculation of the test animals mimics the natural transmission of smallpox, thus representing a suitable model to study pathogenesis and to evaluate new vaccines against orthopoxvirus infection. However, the pathogenic mechanisms leading to death are still unclear. Therefore, our study aimed at investigating the kinetics of pathological alterations to clarify the pathogenesis in calpox virus infection. Following intranasal inoculation with two different viral doses, common marmosets were sacrificed on days 3, 5, 7, 10 and 12 post inoculation. Collected tissue was screened using histopathology, immunohistochemistry, transmission electron microscopy, and virological assays. Our data suggest that primary replication took place in nasal and bronchial epithelia followed by secondary replication in submandibular lymph nodes and spleen. Parallel to viremia at day 7, virus was detectable in many organs, mainly located in epithelial cells and macrophages, as well as in endothelial cells. Based on the onset of clinical signs, the histological and ultrastructural lesions and the immunohistochemical distribution pattern of the virus, the incubation period was defined to last 11 days, which resembles human smallpox. In conclusion, the data indicate that the calpox model is highly suitable for studying orthopoxvirus-induced disease.

  18. Experimental infection of pigs with two East European variants of Type 1 PRRSV

    DEFF Research Database (Denmark)

    Hjulsager, Charlotte Kristiane; Larsen, Lars Erik; Heegaard, Peter M. H.

    Porcine reproductive and respiratory syndrome viruses (PRRSV) have been divided into Type 1 (European) and Type 2 (North American) viruses. PRRSV are very diverse and Type 1 viruses have even been further divided into subtypes. While Type 1 viruses from Western Europe belong to subtype 1, viruses...... the subtype 1 strains. The aim of this project was to study the infection dynamics and clinical and pathological impact of two east European Type 1 strains. In an experimental trial, infection of pigs with the Russian subtype 2 strain “Ili6” and the Belarusian atypical isolate “Bor59” were compared...... to an early “Lelystad-like” Danish subtype 1 isolate “18794”. Groups of seven pigs of unique high sanitary status were infected with one of the three PRRSV isolates, and a fourth group served as sham-inoculated controls. The pigs were monitored for 24 days, and nasal swabs and blood samples were taken at 0, 3...

  19. Ivermectin: activity against larval Strongylus vulgaris and adult Trichostrongylus axei in experimental infections in ponies.

    Science.gov (United States)

    Lyons, E T; Drudge, J H; Tolliver, S C

    1982-08-01

    Activity of ivermectin, administered IM at the dosage rate of 200 micrograms/kg of body weight, was evaluated in controlled tests against migrating larvae of Strongylus vulgaris and adult Trichostrongylus axei in experimental infections in 6 ponies raised worm-free. Ponies were given 2,190 or 2,400 infective 3rd-stage larvae of S vulgaris at 7 days before treatment and 22,000 or 22,750 infective 3rd-stage larvae of T axei at 42 or 45 days before treatment. Three ponies were given ivermectin plus vehicle, and 3 ponies were given the vehicle only; the ponies were euthanatized 7 or 9 days after treatment. At necropsy, 4th-stage S vulgaris larvae were not recovered from visceral arteries of the 3 ivermectin plus vehicle-treated ponies, but 21 to 40 larvae were recovered from each of the 3 vehicle-treated ponies. Also at necropsy, adult T axei (140 specimens) were recovered from only 1 ot the 3 ivermectin plus vehicle-treated ponies, but 4,610 to 6,410 specimens were found in each of the 3 vehicle-treated ponies. Toxicosis was not observed after treatment.

  20. Experimental Cowpox Virus (CPXV) Infections of Bank Voles: Exceptional Clinical Resistance and Variable Reservoir Competence.

    Science.gov (United States)

    Franke, Annika; Ulrich, Rainer G; Weber, Saskia; Osterrieder, Nikolaus; Keller, Markus; Hoffmann, Donata; Beer, Martin

    2017-12-19

    Cowpox virus (CPXV) is a zoonotic virus and endemic in wild rodent populations in Eurasia. Serological surveys in Europe have reported high prevalence in different vole and mouse species. Here, we report on experimental CPXV infections of bank voles ( Myodes glareolus ) from different evolutionary lineages with a spectrum of CPXV strains. All bank voles, independently of lineage, sex and age, were resistant to clinical signs following CPXV inoculation, and no virus shedding was detected in nasal or buccal swabs. In-contact control animals became only rarely infected. However, depending on the CPXV strain used, inoculated animals seroconverted and viral DNA could be detected preferentially in the upper respiratory tract. The highest antibody titers and virus DNA loads in the lungs were detected after inoculation with two strains from Britain and Finland. We conclude from our experiments that the role of bank voles as an efficient and exclusive CPXV reservoir seems questionable, and that CPXV may be maintained in most regions by other hosts, including other vole species. Further investigations are needed to identify factors that allow and modulate CPXV maintenance in bank voles and other potential reservoirs, which may also influence spill-over infections to accidental hosts.

  1. Experimental infection of Marmota monax with a novel hepatitis A virus.

    Science.gov (United States)

    Yu, Jie-Mei; Li, Li-Li; Xie, Guang-Cheng; Zhang, Cui-Yuan; Ao, Yuan-Yun; Duan, Zhao-Jun

    2018-05-01

    To establish an animal model for the newly identified Marmota Himalayana hepatovirus, MHHAV, so as to develop a better understanding of the infection of hepatitis A viruses. Five experimental woodchucks (Marmota monax) were inoculated intravenously with the purified MHHAV from wild woodchuck feces. One animal injected with PBS was defined as a control. Feces and blood were routinely collected. After the animals were subjected to necropsy, different tissues were collected. The presence of viral RNA and negative sense viral RNA was analyzed in all the samples and histopathological and in situ hybridization analysis was performed for the tissues. MHHAV infection caused fever but no severe symptoms or death. Virus was shed in feces beginning at 2 dpi, and MHHAV RNA persisted in feces for ~2 months, with a biphasic increase, and in blood for ~30 days. Viral RNA was detected in all the tissues, with high levels in the liver and spleen. Negative-strand viral RNA was detected only in the liver. Furthermore, the animals showed histological signs of hepatitis at 45 dpi. MHHAV can infect M. monax and is associated with hepatic disease. Therefore, this animal can be used as a model of HAV pathogenesis and to evaluate antiviral and anticancer therapeutics.

  2. Experimental intraocular infection of exotic cockerels with field strain of velogenic Newcastle disease virus in Nigeria

    Directory of Open Access Journals (Sweden)

    Samaila Jonathan Badau

    2015-12-01

    Full Text Available Experimental intraocular (conjunctival infection of exotic cockerels with a new field strain of viscerotropic velogenic Newcastle Disease Virus (NDV was conducted to explore the concurrence of some pathological changes with humoral immune responses. After the NDV infection of 4-week-old cockerels, pathologic changes and antibody responses were observed. The clinical signs observed after the artificial inoculation included inappetence, depression, diarrhea, dyspnea, wing and leg paralysis, torticollis and weight loss. Morbidity due to the NDV was 100%, but mortality was 80% by day 18-21 post-infection. Early hyperthermia followed by terminal hypothermia, decreased packed cell volume (PCV, and 231.4 folds peak-antibody response were observed. Necrotic and/or inflammatory lesions were present in the proventriculus, intestine, liver, spleen, kidney and brain. Neurologic and digestive tract perturbations occurred in 10% and 85% of cases, respectively. The disease consistently caused stunted growth, decreased PCV, and necro-inflammatroy lesions concurrent with antibody response, suggesting probable involvement of immune-mediated mechanisms and cell membrane desialylation by viral neuraminidase in the pathogenesis.

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

    Science.gov (United States)

    Irikov, O A; Kovalenko, F P

    2007-01-01

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

  4. Experimental Pseudomonas anguilliseptica infection in turbot Psetta maxima (L.: a histopathological and immunohistochemical study

    Directory of Open Access Journals (Sweden)

    JL Romalde

    2009-06-01

    Full Text Available Experimental infection with Pseudomonas anguilliseptica was performed both by intraperitoneal (i.p. and bath route on juvenile turbot (Psetta maxima in order to evaluate the pathology induced. Turbot was found to be sensitive to i.p. challenge (1.7x106 CFU/fish but no to bath exposure. The i.p. challenge induced septicaemic infection and mortality. Externally, moribund fish showed distended abdomen and pale areas at day 9. The gross pathological internal signs present were abundant ascitic fluid in the peritoneal cavity, pale and enlarged spleen, pale and friable liver, and congestive and dilated gut with yellowish exudates. On histopathological examination, bacterial invasion was common in all the tissues studied but the most prominent pathological changes were observed in gut, spleen and kidney after 7 day with features of necrosis. The immunohistochemical findings support the widespread localization of the bacteria after the i.p. injection since the P. anguilliseptica was detected in spleen from day 1 post injection, in liver, kidney and gut from day 4, in muscle from day 7 and in brain from day 9. The difficulties in infecting healthy fish by bath challenge can be explained by the opportunistic nature of this pathogen.

  5. Biochemical studies in experimentally Escherichia coli infected broiler chicken supplemented with neem (Azadirachta indica leaf extract

    Directory of Open Access Journals (Sweden)

    Vikash Sharma

    2015-11-01

    Full Text Available Aim: An experimental study was conducted on 192-day-old broiler chicks for evaluating the effect of 10% neem leaf extract (NLE supplementationon biochemical parameters in chickens experimentally infected with Escherichia coli O78 at 107 CFU/0.5 ml at 7 days of age. Materials and Methods: The 192-day-old broiler chicks were procured. These chicks were divided into two groups (A and B containing 96 birds each on the 1st day. Diet of all the chicks of Group A was supplemented with 10%NLE in water, whereas chicks of Group B were given feed and water devoid of NLE supplementation throughout the experiment. After rearing for 1 week, chicks of both the groups (A and B were again divided into two subgroups (Group A into A1 and A2 and Group B into B1 and B2 of 54 and 42 birds, respectively. At the age of 7 days all the chicks of groups A1 and B1 were injected with E. coli O78 at 107 CFU/0.5 ml intraperitoneally. Blood samples were collected from six chicks from each group at day 0, 2, 4, 7, 14, 21, 28 days post-infection and serum was separated for biochemical studies. Results: There was a significant increase in serum alanine transaminase (ALT, aspartate transaminase (AST, lactate dehydrogenase (LDH activities, globulin concentration and a decrease in total protein (TP, albumin concentrations, and alkaline phosphatase (ALP activity in both the infected groups. However, the changes in biochemical values, i.e., ALT, AST, LDH, ALP, TP, albumin, and globulin wereof lower magnitude in NLE supplemented group suggesting hepatoprotective and cardioprotective effect of NLE. Conclusions: Fromthe present study, it is reasonable to conclude that significant increase in the value of ALT, AST, LDH, globulin, and significant decrease in the value of ALP, TP, and albumin was of lower magnitude in supplemented infected group (A1 as compared to non-supplemented infected group (B1 suggesting hepatoprotective and cardioprotective effect of NLE.

  6. Is Salvage of Recently Infected Breast Implant After Breast Augmentation or Reconstruction Possible? An Experimental Study.

    Science.gov (United States)

    Castus, P; Heymans, O; Melin, P; Renwart, L; Henrist, C; Hayton, E; Mordon, S; Leclère, F M

    2018-04-01

    The reinsertion of an infected implant when peri-prosthetic infection occurs early after breast augmentation or breast reconstruction remains controversial. In this experimental study, the authors tried to remove bacteria, and their biofilm, from the colonized surface of breast prostheses, without damaging their integrity. A total of 112 shell samples of silicone breast prostheses, smooth (SPSS) and textured (TPSS), were colonized by S. epidermidis (SE) or S. aureus (SA) strains, all able to produce biofilms. After 15 days, all the samples were removed from the contaminated culture broth and constituted 4 groups of 20 contaminated samples: SPSS/SE (group I), SPSS/SA (group II), TPSS/SE (group III), TPSS/SE (group IV). In another group-group SEM-, 16 colonized samples were used for documentation with scanning electron microscopy (SEM). The remaining 16 samples were used to test the limits of detection of the sterility test. All samples of groups I-IV and 8 samples of group SEM were « washed » with a smooth brush in a povidone-iodine bath and rinsed with saline solution. A subset of the washed samples was sent for SEM and the others were immersed in sterile broth and were incubated at 35 °C for 3 weeks (groups I-IV). Fifteen days after contamination, all the samples in groups I-IV were colonized. In the SEM group, SEM images attested to the presence of bacteria in biofilm attached to the shells. After cleaning, SEM did not reveal any bacteria and there was no visible alteration in the outer structure of the shell. Sterility tests performed after decontamination in groups I-IV remained negative for all the samples. Breast prostheses recently contaminated with Staphylococci, frequently involved in peri-prosthetic breast implant infection and capable of producing biofilms, can be efficiently decontaminated by the procedure used in this study. Our decontamination procedure did not alter the surface structure of the prostheses. This decontamination procedure

  7. Detection and distribution of ostreid herpesvirus 1 in experimentally infected Pacific oyster spat.

    Science.gov (United States)

    Segarra, Amélie; Baillon, Laury; Faury, Nicole; Tourbiez, Delphine; Renault, Tristan

    2016-01-01

    High mortality rates are reported in spat and larvae of Pacific oyster Crassostrea gigas and associated with ostreid herpesvirus 1 (OsHV-1) detection in France. Although the viral infection has been experimentally reproduced in oyster larvae and spat, little knowledge is currently available concerning the viral entry and its distribution in organs and tissues. This study compares OsHV-1 DNA and RNA detection and localization in experimentally infected oysters using two virus doses: a low dose that did not induce any mortality and a high dose inducing high mortality. Real time PCR demonstrated significant differences in terms of viral DNA amounts between the two virus doses. RNA transcripts were detected in oysters receiving the highest dose of viral suspension whereas no transcript was observed in oysters injected with the low dose. This study also allowed observing kinetics of viral DNA and RNA detection in different tissues of oyster spat. Finally, viral detection was significantly different in function of tissues (p<0.005), time (p<0.005) with an interaction between tissues and time (p<0.005) for each probe. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Peste des Petits Ruminants Virus Tissue Tropism and Pathogenesis in Sheep and Goats following Experimental Infection

    Science.gov (United States)

    Truong, Thang; Boshra, Hani; Embury-Hyatt, Carissa; Nfon, Charles; Gerdts, Volker; Tikoo, Suresh; Babiuk, Lorne A.; Kara, Pravesh; Chetty, Thireshni; Mather, Arshad; Wallace, David B.; Babiuk, Shawn

    2014-01-01

    Peste des petits ruminants (PPR) is a viral disease which primarily affects small ruminants, causing significant economic losses for the livestock industry in developing countries. It is endemic in Saharan and sub-Saharan Africa, the Middle East and the Indian sub-continent. The primary hosts for peste des petits ruminants virus (PPRV) are goats and sheep; however recent models studying the pathology, disease progression and viremia of PPRV have focused primarily on goat models. This study evaluates the tissue tropism and pathogenesis of PPR following experimental infection of sheep and goats using a quantitative time-course study. Upon infection with a virulent strain of PPRV, both sheep and goats developed clinical signs and lesions typical of PPR, although sheep displayed milder clinical disease compared to goats. Tissue tropism of PPRV was evaluated by real-time RT-PCR and immunohistochemistry. Lymph nodes, lymphoid tissue and digestive tract organs were the predominant sites of virus replication. The results presented in this study provide models for the comparative evaluation of PPRV pathogenesis and tissue tropism in both sheep and goats. These models are suitable for the establishment of experimental parameters necessary for the evaluation of vaccines, as well as further studies into PPRV-host interactions. PMID:24498032

  9. Natural controlled HIV infection: Preserved HIV-specific immunity despite undetectable replication competent virus

    International Nuclear Information System (INIS)

    Kloosterboer, Nico; Groeneveld, Paul H.P.; Jansen, Christine A.; Vorst, Teun J.K. van der; Koning, Fransje; Winkel, Carel N.; Duits, Ashley J.; Miedema, Frank; Baarle, Debbie van; Rij, Ronald P. van; Brinkman, Kees; Schuitemaker, Hanneke

    2005-01-01

    Long-term non-progressive HIV infection, characterized by low but detectable viral load and stable CD4 counts in the absence of antiviral therapy, is observed in about 5% of HIV-infected patients. Here we identified four therapy naive individuals who are strongly seropositive for HIV-1 but who lack evidence of detectable HIV p24 antigen, plasma RNA, and proviral DNA in routine diagnostic testing. With an ultrasensitive PCR, we established that frequencies of pol proviral DNA sequences were as low as 0.2-0.5 copies/10 6 PBMC. HIV could not be isolated using up to 30 x 10 6 patient PBMC. One individual was heterozygous for CCR5 Δ32, but CCR5 expression on CD4 + T cells was normal to high in all four individuals. In vitro R5 and X4 HIV-1 susceptibility of CD8-depleted PBMC of all study subjects was significantly lower than the susceptibility of CD8-depleted PBMC of healthy blood donors. All individuals expressed protective HLA-B*58s alleles and showed evidence of HIV-specific cellular immunity either by staining with HLA-B*57 tetramers folded with an HIV RT or gag peptide or after stimulation with HIV-1 p24 gag, RT, or nef peptides in ELIspot analysis. HIV-specific CD4 + T helper cells were demonstrated by proliferation of CD4 + T cells and intracellular staining for IL-2 and IFNγ after stimulation with an HIV-gag peptide pool. Sera of all individuals showed antibody-mediated neutralization of both R5 and X4 HIV-1 variants. These data implicate that very low-level antigen exposure is sufficient for sustained HIV-specific immunity and suggest the possibility of a multi-factorial control of HIV infection

  10. EXPERIMENTAL CHALLENGE STUDY OF FV3-LIKE RANAVIRUS INFECTION IN PREVIOUSLY FV3-LIKE RANAVIRUS INFECTED EASTERN BOX TURTLES (TERRAPENE CAROLINA CAROLINA) TO ASSESS INFECTION AND SURVIVAL.

    Science.gov (United States)

    Hausmann, Jennifer C; Wack, Allison N; Allender, Matthew C; Cranfield, Mike R; Murphy, Kevin J; Barrett, Kevin; Romero, Jennell L; Wellehan, James F X; Blum, Stella A; Zink, M Christine; Bronson, Ellen

    2015-12-01

    The Maryland Zoo in Baltimore experienced an outbreak of Frog virus-3 (FV3)-like ranavirus during the summer of 2011, during which 14 of 27 (52%) of its captive eastern box turtles (Terrapene carolina carolina) survived. To assess survival, immunity, and viral shedding, an experimental challenge study was performed in which the surviving, previously infected turtles were reinfected with the outbreak strain of FV3-like ranavirus. Seven turtles were inoculated with virus intramuscularly and four control turtles received saline intramuscularly. The turtles were monitored for 8 wk with blood and oral swabs collected for quantitative polymerase chain reaction (qPCR). During that time, one of seven (14%) inoculated turtles and none of the controls (0%) died; there was no significant difference in survival. Clinical signs of the inoculated turtles, except for the turtle that died, were mild compared to the original outbreak. Quantitative PCR for FV3-like ranavirus on blood and oral swabs was positive for all inoculated turtles and negative for all controls. The turtle that died had intracytoplasmic inclusion bodies in multiple organs. Three inoculated and two control turtles were euthanized at the end of the study. No inclusion bodies were present in any of the organs. Quantitative PCR detected FV3-like ranavirus in the spleen of a control turtle, which suggested persistence of the virus. The surviving five turtles were qPCR-negative for FV3-like ranavirus from blood and oral swabs after brumation. Quantitative PCR for Terrapene herpesvirus 1 found no association between ranavirus infection and herpesvirus loads. In conclusion, previously infected eastern box turtles can be reinfected with the same strain of FV3-like ranavirus and show mild to no clinical signs but can shed the virus from the oral cavity.

  11. Radioimmunoimaging of subacute infective endocarditis using a technetium-99m monoclonal granulocyte-specific antibody

    Energy Technology Data Exchange (ETDEWEB)

    Munz, D L; Sandrock, D; Emrich, D [Goettingen Univ. (Germany). Abt. fuer Nuklearmedizin; Morguet, A J; Heim, A; Sold, G; Figulla, H R; Kreuzer, H [Goettingen Univ. (Germany). Abt. fuer Kardiologie und Pulmonologie

    1991-12-01

    Immunoscintigraphy with a technetium-99m murine monoclonal IgG{sub 1} antibody directed against non-specific cross-reacting antigen (NCA-95) and carcinoembryonic antigen was performed with 20 patients with suspected subacute infective endocarditis (SIE) and 6 controls with suspected inflammatory/infectious disease elsewhere in the body. Immunoscintigraphy and echocardiography localised SIE in 11 of 15 patients in whom the disease could be confirmed. In 4 patients with validated SIE, the immunoscan was abnormal, and the echocardiogram was normal. In another 4 patients, the result was exactly the opposite. These findings suggest that the combination of immunoscintigraphy and echocardiography improves diagnostic efficacy in patients with suspected SIE. (orig.).

  12. Infective endocarditis: the specific features of its course, the criteria for diagnosis, differential diagnosis (part II

    Directory of Open Access Journals (Sweden)

    B S Belov

    2008-01-01

    Full Text Available Infective endocarditis (IE is today characterized by polyetiology due to a wide range of pathogens. The paper describes the specific features of the clinical picture of the disease in relation to the etiological agent, which have, in some cases, a crucial role in the choice of empiric antibiotic therapy. Significant clinical polymorphism, obscure symptoms, and monosyndromic onset as guises all enhance the importance of the differential diagnosis of IE, at its early stages in particular. Basic approaches to differentiating IE from the diseases in which differentially diagnostic problems arise to the utmost are outlined.

  13. Radioimmunoimaging of subacute infective endocarditis using a technetium-99m monoclonal granulocyte-specific antibody

    International Nuclear Information System (INIS)

    Munz, D.L.; Sandrock, D.; Emrich, D.; Morguet, A.J.; Heim, A.; Sold, G.; Figulla, H.R.; Kreuzer, H.

    1991-01-01

    Immunoscintigraphy with a technetium-99m murine monoclonal IgG 1 antibody directed against non-specific cross-reacting antigen (NCA-95) and carcinoembryonic antigen was performed with 20 patients with suspected subacute infective endocarditis (SIE) and 6 controls with suspected inflammatory/infectious disease elsewhere in the body. Immunoscintigraphy and echocardiography localised SIE in 11 of 15 patients in whom the disease could be confirmed. In 4 patients with validated SIE, the immunoscan was abnormal, and the echocardiogram was normal. In another 4 patients, the result was exactly the opposite. These findings suggest that the combination of immunoscintigraphy and echocardiography improves diagnostic efficacy in patients with suspected SIE. (orig.)

  14. Specific removal of autoantibodies by extracorporeal immunoadsorption ameliorates experimental autoimmune myasthenia gravis.

    Science.gov (United States)

    Lazaridis, Konstantinos; Dalianoudis, Ioannis; Baltatzidi, Vasiliki; Tzartos, Socrates J

    2017-11-15

    Myasthenia gravis (MG) is caused by autoantibodies, the majority of which target the muscle acetylcholine receptor (AChR). Plasmapheresis and IgG-immunoadsorption are useful therapy options, but are highly non-specific. Antigen-specific immunoadsorption would remove only the pathogenic autoantibodies, reducing the possibility of side effects while maximizing the benefit. We have extensively characterized such adsorbents, but in vivo studies are missing. We used rats with experimental autoimmune MG to perform antigen-specific immunoadsorptions over three weeks, regularly monitoring symptoms and autoantibody titers. Immunoadsorption was effective, resulting in a marked autoantibody titer decrease while the immunoadsorbed, but not the mock-treated, animals showed a dramatic symptom improvement. Overall, the procedure was found to be efficient, suggesting the subsequent initiation of clinical trials. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Limits of variation, specific infectivity, and genome packaging of massively recoded poliovirus genomes.

    Science.gov (United States)

    Song, Yutong; Gorbatsevych, Oleksandr; Liu, Ying; Mugavero, JoAnn; Shen, Sam H; Ward, Charles B; Asare, Emmanuel; Jiang, Ping; Paul, Aniko V; Mueller, Steffen; Wimmer, Eckard

    2017-10-10

    Computer design and chemical synthesis generated viable variants of poliovirus type 1 (PV1), whose ORF (6,189 nucleotides) carried up to 1,297 "Max" mutations (excess of overrepresented synonymous codon pairs) or up to 2,104 "SD" mutations (randomly scrambled synonymous codons). "Min" variants (excess of underrepresented synonymous codon pairs) are nonviable except for P2 Min , a variant temperature-sensitive at 33 and 39.5 °C. Compared with WT PV1, P2 Min displayed a vastly reduced specific infectivity (si) (WT, 1 PFU/118 particles vs. P2 Min , 1 PFU/35,000 particles), a phenotype that will be discussed broadly. Si of haploid PV presents cellular infectivity of a single genotype. We performed a comprehensive analysis of sequence and structures of the PV genome to determine if evolutionary conserved cis-acting packaging signal(s) were preserved after recoding. We showed that conserved synonymous sites and/or local secondary structures that might play a role in determining packaging specificity do not survive codon pair recoding. This makes it unlikely that numerous "cryptic, sequence-degenerate, dispersed RNA packaging signals mapping along the entire viral genome" [Patel N, et al. (2017) Nat Microbiol 2:17098] play the critical role in poliovirus packaging specificity. Considering all available evidence, we propose a two-step assembly strategy for +ssRNA viruses: step I, acquisition of packaging specificity, either ( a ) by specific recognition between capsid protein(s) and replication proteins (poliovirus), or ( b ) by the high affinity interaction of a single RNA packaging signal (PS) with capsid protein(s) (most +ssRNA viruses so far studied); step II, cocondensation of genome/capsid precursors in which an array of hairpin structures plays a role in virion formation.

  16. [INTESTINAL FAILURE AND YERSINIA PSEUDOTUBERCULOSIS TRANSLOCATION IN THE DEVELOPMENTOF EXPERIMENTAL GENERALIZED INFECTION].

    Science.gov (United States)

    Chicherin, I Yu; Pogorelky, I P; Lundovskikh, I A; Darmov, I V; Gorshkov, A S; Shabalina, M R

    2016-01-01

    To determine the value of intestinal failure and translocation of bacteria Y. pseudotuberculosis, and normal intestinal microbiota in the initiation and generalization of infection in experimental pseudotuberculosis in conventional white mice, as well as pathological manifestation of it as a response to the adhesion and colonization of the mucosus membrane by pathogenic bacteria Y. pseudotuberculosis. Experimental models of pseudotuberculosis in conventional white mice used the pathogenic Y. pseudotuberculosis 147 serotype I strain, containing a calcium-dependence plasmid with a molecular weight of 47 MDa. Cultivation of the pseudotuberculosis pathogen given its psychrophilic was performed on Hottinger agar at a temperature of (4-5) °C. The lactobacilli strain L plantarum 8P-A3 was isolated from a lyophilized commercial probiotic Lactobacterin (manufactured by "NPO Microgen", Russia) and used to obtain native culture supernatant fluid of lactobacilli, the composition of which was detected by gas-liquid chromatography with mass-selective detection. Gentamicin for parenteral administration was manufactured by JSC "Biochemist", Russia. Pathomorphological examination was performed on the 4-6th day of the experiment. Fragments of the small intestine, liver, kidneys, and lungs from dead animals were chosen for examination. Tissues were fixed in 10% neutral formalin, dehydrated in isopropanol and embedded in paraffin. Preparations were stained with Ehrlich hematoxylin and eosin, examined on the microscope "Mikmed-2" (JSC "LOMO", Russia) under magnification x 200-x1000. Statistical processing of the experimental results was carried out according to the method of Kerber in modification of I.P. Ashmarin and A.A. Vorobyov. The role of intestinal failure and translocation of bacteria Y. pseudotuberculosis, and normal intestinal microbiota in the initiation and generalization of infection in animals has been found. It has been proved that the oral administration of supernatant

  17. The nonstructural proteins of Nipah virus play a key role in pathogenicity in experimentally infected animals.

    Directory of Open Access Journals (Sweden)

    Misako Yoneda

    Full Text Available Nipah virus (NiV P gene encodes P protein and three accessory proteins (V, C and W. It has been reported that all four P gene products have IFN antagonist activity when the proteins were transiently expressed. However, the role of those accessory proteins in natural infection with NiV remains unknown. We generated recombinant NiVs lacking V, C or W protein, rNiV(V-, rNiV(C-, and rNiV(W-, respectively, to analyze the functions of these proteins in infected cells and the implications in in vivo pathogenicity. All the recombinants grew well in cell culture, although the maximum titers of rNiV(V- and rNiV(C- were lower than the other recombinants. The rNiV(V-, rNiV(C- and rNiV(W- suppressed the IFN response as well as the parental rNiV, thereby indicating that the lack of each accessory protein does not significantly affect the inhibition of IFN signaling in infected cells. In experimentally infected golden hamsters, rNiV(V- and rNiV(C- but not the rNiV(W- virus showed a significant reduction in virulence. These results suggest that V and C proteins play key roles in NiV pathogenicity, and the roles are independent of their IFN-antagonist activity. This is the first report that identifies the molecular determinants of NiV in pathogenicity in vivo.

  18. Ketoconazole modulates the infectivity of Ichthyophonus sp. (Mesomycetozoa) in vivo in experimentally injected European sea bass.

    Science.gov (United States)

    Hontoria, Francisco; González, Ma Angeles; Sitjà-Bobadilla, Ariadna; Palenzuela, Oswaldo; Alvarez-Pellitero, Pilar

    2013-09-03

    In vitro studies have confirmed the inhibitory effect of the azol-derivative ketoconazole (KZ) on the growth of Ichthyophonus, an important pathogen causing epizootics in wild and cultured fish. We evaluated the effect of KZ in vivo in European sea bass Dicentrarchus labrax experimentally infected with the same Ichthyophonus isolate. Liposomes were used to vehiculate different doses of KZ to increase the effect on Ichthyophonus and lower the toxicity of the drug, and KZ toxicity was assessed in cultured sea bass juveniles. We also studied the effect of liposome-vehiculated KZ included in medicated food on ichthyophoniasis. KZ causes clear toxic effects in D. labrax juveniles at doses >80 mg kg-1, apparent in the reduced survival of fish and histological alterations to livers, kidneys and spleens. Fish injected with Ichthyophonus and treated with KZ dosages of ≤80 mg kg-1 d-1 presented lower ichthyophoniasis prevalence, fewer organs infected per fish, and fewer spores in the affected organs than the untreated fish. KZ seems to delay the onset of infection, but cannot stop further progression once established. However, this behaviour is not clearly reflected in the biometric and haematological data collected from these fish. We hypothesise that KZ's delaying effect would increase, if lower infective doses (more similar to natural situations) were used. The drug administration vehicle (liposomes vs. emulsions) did not affect the results. Our data confirm the potential utility of KZ in treating ichthyophoniasis and reveal its low toxicity for sea bass. Nevertheless, the optimal dose and appropriate application protocol remain to be determined.

  19. Experimental gonococcal infection in male volunteers: Cumulative experience with Neisseria gonorrhoeae strains FA1090 and MS11mkC

    Directory of Open Access Journals (Sweden)

    Marcia Metzgar Hobbs

    2011-05-01

    Full Text Available Experimental infection of male volunteers with Neisseria gonorrhoeae is safe and reproduces the clinical features of naturally acquired gonococcal urethritis. Human inoculation studies have helped define the natural history of experimental infection with two well-characterized strains of N. gonorrhoeae, FA1090 and MS11mkC. The human model has proved useful for testing the importance of putative gonococcal virulence factors for urethral infection in men. Studies with isogenic mutants have improved our understanding of the requirements for gonococcal LOS structures, pili, opacity proteins, IgA1 protease and the ability of infecting organisms to obtain iron from human transferrin and lactoferrin during uncomplicated urethritis. The model also presents opportunities to examine innate host immune responses that may be exploited or improved in development and testing of gonococcal vaccines. Here we review results to date with human experimental gonorrhea.

  20. Changes of the Specific Infectivity of Tracer Phages during Transport in Porous Media.

    Science.gov (United States)

    Ghanem, Nawras; Trost, Manuel; Sánchez Fontanet, Laura; Harms, Hauke; Chatzinotas, Antonis; Wick, Lukas Y

    2018-03-20

    Phages (i.e., viruses infecting bacteria) are considered to be good indicators and tracers for fecal pollution, hydraulic flow, or colloidal transport in the subsurface. They are typically quantified as total virus particles (VLP) or plaque forming units (PFU) of infectious phages. As transport may lead to phage deactivation, VLP quantification can overestimate the number of infectious phages. In contrast, PFU counts may underestimate the transport of total virus particles. Using PFU and tunable resistive pulse sensing-based counting for active and total phages, respectively, we quantified the effect of transport through laboratory percolation columns on the specific infectivity (SI). The SI is defined by the ratio of total VLP to PFU and is a measure for the minimum particle numbers needed to create a single infection. Transport of three marine tracer phages and the coli-phage (T4) was described by colloidal filtration theory. We found that apparent collision efficiencies of active and total phages differed. Depending on the phage properties (e.g., morphology or hydrophobicity), passage through a porous medium led to either an increasing or decreasing SI of effluent phages. Our data suggest that both phage mass recovery and the SI should be considered in quantitative phage tracer experiments.

  1. Cause-specific excess mortality in siblings of patients co-infected with HIV and hepatitis C virus

    DEFF Research Database (Denmark)

    Hansen, AB; Lohse, Nicolai; Gerstoft, J

    2007-01-01

    BACKGROUND: Co-infection with hepatitis C in HIV-infected individuals is associated with 3- to 4-fold higher mortality among these patients' siblings, compared with siblings of mono-infected HIV-patients or population controls. This indicates that risk factors shared by family members partially...... account for the excess mortality of HIV/HCV-co-infected patients. We aimed to explore the causes of death contributing to the excess sibling mortality. METHODOLOGY AND PRINCIPAL FINDINGS: We retrieved causes of death from the Danish National Registry of Deaths and estimated cause-specific excess mortality...... rates (EMR) for siblings of HIV/HCV-co-infected individuals (n = 436) and siblings of HIV mono-infected individuals (n = 1837) compared with siblings of population controls (n = 281,221). Siblings of HIV/HCV-co-infected individuals had an all-cause EMR of 3.03 (95% CI, 1.56-4.50) per 1,000 person...

  2. Specific serum protein changes associated with primary and secondary Strongylus vulgaris infections in pony yearlings.

    Science.gov (United States)

    Kent, J E

    1987-03-01

    The concentrations of haptoglobin, immunoglobin (Ig)G(T) and IgG were measured in the serum of four previously parasite-free pony yearlings following a single dose of 700 (Group H) or 200 (Group L) stage three Strongylus vulgaris larvae (L3) and following a reinfection with the same doses 34 weeks later. The results are compared with an uninfected control pony. The haptoglobin concentration increased during Weeks 1 to 6 and 14 to 17 after infection in the serum of the ponies receiving 200 L3, but in only one pony dosed with 700 L3 (during Weeks 1 to 16). The serum haptoglobin also increased during the first seven weeks after the second infection, in three of the four ponies following the second dose of larvae. The serum IgG(T) concentration started to increase from Week 6 or 9 in the ponies given 700 L3, reaching peaks of 44 and 32 g/litre respectively, eight to nine weeks later, compared with a peak of 16 g/litre 20 to 22 weeks after infection in ponies dosed with 200 L3. The IgG(T) concentration increased to a maximum of 25 g/litre in the serum of only one of the four ponies after the reinfection. The serum IgG concentration in all ponies increased nearly twofold during the first eight weeks after both the primary and secondary dose of larvae. It is concluded that the measurement of specific proteins is more reliable and quicker than the electrophoretic separation and quantitation of protein bands, in tracing changes in serum proteins following the artificial infection of ponies with S vulgaris larvae.

  3. Telomere length dynamics in human memory T cells specific for viruses causing acute or latent infections.

    Science.gov (United States)

    O'Bryan, Joel M; Woda, Marcia; Co, Mary; Mathew, Anuja; Rothman, Alan L

    2013-08-26

    Declining telomere length (TL) is associated with T cell senescence. While TL in naïve and memory T cells declines with increasing age, there is limited data on TL dynamics in virus-specific memory CD4+ T cells in healthy adults. We combined BrdU-labeling of virus-stimulated T cells followed with flow cytometry-fluorescent in situ hybridization for TL determination. We analyzed TL in T cells specific for several virus infections: non-recurring acute (vaccinia virus, VACV), recurring-acute (influenza A virus, IAV), and reactivating viruses (varicella-zoster virus, VZV, and cytomegalovirus, CMV) in 10 healthy subjects. Additionally, five subjects provided multiple blood samples separated by up to 10 years. VACV- and CMV-specific T cells had longer average TL than IAV-specific CD4+ T cells. Although most virus-specific cells were CD45RA-, we observed a minor population of BrdU+ CD45RA+ T cells characterized by long telomeres. Longitudinal analysis demonstrated a slow decline in average TL in virus-specific T cells. However, in one subject, VZV reactivation led to an increase in average TL in VZV-specific memory T cells, suggesting a conversion of longer TL cells from the naïve T cell repertoire. TLs in memory CD4+ T cells in otherwise healthy adults are heterogeneous and follow distinct virus-specific kinetics. These findings suggests that the distribution of TL and the creation and maintenance of long TL memory T cells could be important for the persistence of long-lived T cell memory.

  4. Cell-specific type I IFN signatures in autoimmunity and viral infection: what makes the difference?

    Directory of Open Access Journals (Sweden)

    Chieko Kyogoku

    Full Text Available Gene expression profiling of peripheral blood mononuclear cells (PBMCs has revealed a crucial role for type I interferon (IFN in the pathogenesis of systemic lupus erythematosus (SLE. However, it is unclear how particular leucocyte subsets contribute to the overall type I IFN signature of PBMCs and whole blood samples.Furthermore, a detailed analysis describing the differences in the IFN signature in autoimmune diseases from that observed after viral infection has not been performed to date. Therefore, in this study, the transcriptional responses in peripheral T helper cells (CD4(+ and monocyte subsets (CD16(- inflammatory and CD16(+ resident monocytes isolated from patients with SLE, healthy donors (ND immunised with the yellow fever vaccine YFV-17Dand untreated controls were compared by global gene expression profiling.It was striking that all of the transcripts that were regulated in response to viral exposure were also found to be differentially regulated in SLE, albeit with markedly lower fold-change values. In addition to this common IFN signature, a pathogenic IFN-associated gene signature was detected in the CD4(+ T cells and monocytes from the lupus patients. IL-10, IL-9 and IL-15-mediated JAK/STAT signalling was shown to be involved in the pathological amplification of IFN responses observed in SLE. Type I IFN signatures identified were successfully applied for the monitoring of interferon responses in PBMCs of an independent cohort of SLE patients and virus-infected individuals. Moreover, these cell-type specific gene signatures allowed a correct classification of PBMCs independent from their heterogenic cellular composition. In conclusion, our data show for the first time that monocytes and CD4 cells are sensitive biosensors to monitor type I interferon response signatures in autoimmunity and viral infection and how these transriptional responses are modulated in a cell- and disease-specific manner.

  5. Sequential Dysfunction and Progressive Depletion of Candida albicans-Specific CD4 T Cell Response in HIV-1 Infection

    Science.gov (United States)

    Liu, Fengliang; Fan, Xiuzhen; Auclair, Sarah; Ferguson, Monique; Sun, Jiaren; Soong, Lynn; Hou, Wei; Redfield, Robert R.; Birx, Deborah L.; Ratto-Kim, Silvia; Robb, Merlin L.; Kim, Jerome H.; Michael, Nelson L.; Hu, Haitao

    2016-01-01

    Loss of immune control over opportunistic infections can occur at different stages of HIV-1 (HIV) disease, among which mucosal candidiasis caused by the fungal pathogen Candida albicans (C. albicans) is one of the early and common manifestations in HIV-infected human subjects. The underlying immunological basis is not well defined. We have previously shown that compared to cytomegalovirus (CMV)-specific CD4 cells, C. albicans-specific CD4 T cells are highly permissive to HIV in vitro. Here, based on an antiretroviral treatment (ART) naïve HIV infection cohort (RV21), we investigated longitudinally the impact of HIV on C. albicans- and CMV-specific CD4 T-cell immunity in vivo. We found a sequential dysfunction and preferential depletion for C. albicans-specific CD4 T cell response during progressive HIV infection. Compared to Th1 (IFN-γ, MIP-1β) functional subsets, the Th17 functional subsets (IL-17, IL-22) of C. albicans-specific CD4 T cells were more permissive to HIV in vitro and impaired earlier in HIV-infected subjects. Infection history analysis showed that C. albicans-specific CD4 T cells were more susceptible to HIV in vivo, harboring modestly but significantly higher levels of HIV DNA, than CMV-specific CD4 T cells. Longitudinal analysis of HIV-infected individuals with ongoing CD4 depletion demonstrated that C. albicans-specific CD4 T-cell response was preferentially and progressively depleted. Taken together, these data suggest a potential mechanism for earlier loss of immune control over mucosal candidiasis in HIV-infected patients and provide new insights into pathogen-specific immune failure in AIDS pathogenesis. PMID:27280548

  6. Effect of photodynamic therapy (PDT) on Enterococcus faecalis biofilm in experimental primary and secondary endodontic infections.

    Science.gov (United States)

    Tennert, Christian; Feldmann, Katharina; Haamann, Edwina; Al-Ahmad, Ali; Follo, Marie; Wrbas, Karl-Thomas; Hellwig, Elmar; Altenburger, Markus J

    2014-11-04

    To determine the antibacterial effect of photodynamic Therapy on Enterococcus faecalis (E. faecalis) biofilms in experimentally infected human root canals in primary infections and endodontic retreatments. One hundred and sixty single-rooted extracted teeth with one root canal were prepared using ProTaper instruments. Seventy specimens were left without root canal filling and autoclaved. The root canals of another 70 specimens were filled with Thermafil and AH Plus and the root canal fillings were removed after 24 hours using ProTaper D files and plasma sterilized. The specimens were infected with a clinical isolate of E. faecalis for 72 hours. Samples were taken using sterile paper points to determine the presence of E. faecalis in the root canals. The specimens were randomly divided into groups according to their treatment with 20 teeth each and a control. In the PDT group the teeth were treated using PDT, consisting of the photosensitizer toluidine blue and the PDT light source at 635 nm. In the NaOCl (sodium hypochlorite) group the root canals were rinsed with 10 mL of 3% NaOCl. In the NaOCl-PDT group the root canals were rinsed with 10 mL of 3% of sodium hypochlorite and then treated with PDT. Samples were taken after treatments using sterile paper points. Additionally, remaining root canal filling material was recovered from the root canal walls. Survival fractions of the samples were calculated by counting colony-forming units. A one-way analysis of variance (ANOVA) was applied to the data to assess the effect of different treatment techniques. Antimicrobial treatment of root canals caused a significant reduction of bacterial load in all groups. NaOCl irrigation eliminated E. faecalis most effectively. PDT alone was less effective compared to NaOCl irrigation and the combination of NaOCl irrigation and PDT. CFU levels recovered from the filling material after NaOCl irrigation of the root canals were 10fold higher compared to PDT and the combination of Na

  7. Dengue serotype cross-reactive, anti-E protein antibodies confound specific immune memory for one year after infection

    Directory of Open Access Journals (Sweden)

    Ying Xiu eToh

    2014-08-01

    Full Text Available Dengue virus has four serotypes and is endemic globally in tropical countries. Neither a specific treatment nor an approved vaccine is available, and correlates of protection are not established. The standard neutralization assay cannot differentiate between serotype-specific and serotype cross-reactive antibodies in patients early after infection, leading to an overestimation of the long-term serotype-specific protection of an antibody response. It is known that the cross-reactive response in patients is temporary but few studies have assessed kinetics and potential changes in serum antibody specificity over time. To better define the specificity of polyclonal antibodies during disease and after recovery, longitudinal samples from patients with primary or secondary DENV-2 infection were collected over a period of one year. We found that serotype cross-reactive antibodies peaked three weeks after infection and subsided within one year. Since secondary patients rapidly produced antibodies specific for the virus envelope (E protein, an E-specific ELISA was superior compared to a virus particle-specific ELISA to identify patients with secondary infections. Dengue infection triggered a massive activation and mobilization of both naïve and memory B cells possibly from lymphoid organs into the blood, providing an explanation for the surge of circulating plasmablasts and the increase in cross-reactive E protein-specific antibodies.

  8. Fungal Infection Induces Sex-Specific Transcriptional Changes and Alters Sexual Dimorphism in the Dioecious Plant Silene latifolia.

    Directory of Open Access Journals (Sweden)

    Niklaus Zemp

    2015-10-01

    Full Text Available Sexual dimorphism, including differences in morphology, behavior and physiology between females and males, is widespread in animals and plants and is shaped by gene expression differences between the sexes. Such expression differences may also underlie sex-specific responses of hosts to pathogen infections, most notably when pathogens induce partial sex reversal in infected hosts. The genetic changes associated with sex-specific responses to pathogen infections on the one hand, and sexual dimorphism on the other hand, remain poorly understood. The dioecious White Campion (Silene latifolia displays sexual dimorphism in floral traits and infection with the smut fungus Micobrotryum lychnidis-dioicae induces a partial sex reversal in females. We find strong sex-specific responses to pathogen infection and reduced sexual dimorphism in infected S. latifolia. This provides a direct link between pathogen-mediated changes in sex-biased gene expression and altered sexual dimorphism in the host. Expression changes following infection affected mainly genes with male-biased expression in healthy plants. In females, these genes were up-regulated, leading to a masculinization of the transcriptome. In contrast, infection in males was associated with down-regulation of these genes, leading to a demasculinization of the transcriptome. To a lesser extent, genes with female-biased expression in healthy plants were also affected in opposite directions in the two sexes. These genes were overall down-regulated in females and up-regulated in males, causing, respectively, a defeminization in infected females and a feminization of the transcriptome in infected males. Our results reveal strong sex-specific responses to pathogen infection in a dioecious plant and provide a link between pathogen-induced changes in sex-biased gene expression and sexual dimorphism.

  9. Fungal Infection Induces Sex-Specific Transcriptional Changes and Alters Sexual Dimorphism in the Dioecious Plant Silene latifolia.

    Science.gov (United States)

    Zemp, Niklaus; Tavares, Raquel; Widmer, Alex

    2015-10-01

    Sexual dimorphism, including differences in morphology, behavior and physiology between females and males, is widespread in animals and plants and is shaped by gene expression differences between the sexes. Such expression differences may also underlie sex-specific responses of hosts to pathogen infections, most notably when pathogens induce partial sex reversal in infected hosts. The genetic changes associated with sex-specific responses to pathogen infections on the one hand, and sexual dimorphism on the other hand, remain poorly understood. The dioecious White Campion (Silene latifolia) displays sexual dimorphism in floral traits and infection with the smut fungus Micobrotryum lychnidis-dioicae induces a partial sex reversal in females. We find strong sex-specific responses to pathogen infection and reduced sexual dimorphism in infected S. latifolia. This provides a direct link between pathogen-mediated changes in sex-biased gene expression and altered sexual dimorphism in the host. Expression changes following infection affected mainly genes with male-biased expression in healthy plants. In females, these genes were up-regulated, leading to a masculinization of the transcriptome. In contrast, infection in males was associated with down-regulation of these genes, leading to a demasculinization of the transcriptome. To a lesser extent, genes with female-biased expression in healthy plants were also affected in opposite directions in the two sexes. These genes were overall down-regulated in females and up-regulated in males, causing, respectively, a defeminization in infected females and a feminization of the transcriptome in infected males. Our results reveal strong sex-specific responses to pathogen infection in a dioecious plant and provide a link between pathogen-induced changes in sex-biased gene expression and sexual dimorphism.

  10. Experimental Oral Herpes Simplex Virus-1 (HSV-1 Co-infection in Simian Immunodeficiency Virus (SIV-Infected Rhesus Macaques

    Directory of Open Access Journals (Sweden)

    Meropi Aravantinou

    2017-12-01

    Full Text Available Herpes simplex virus 1 and 2 (HSV-1/2 similarly initiate infection in mucosal epithelia and establish lifelong neuronal latency. Anogenital HSV-2 infection augments the risk for sexual human immunodeficiency virus (HIV transmission and is associated with higher HIV viral loads. However, whether oral HSV-1 infection contributes to oral HIV susceptibility, viremia, or oral complications of HIV infection is unknown. Appropriate non-human primate (NHP models would facilitate this investigation, yet there are no published studies of HSV-1/SIV co-infection in NHPs. Thus, we performed a pilot study for an oral HSV-1 infection model in SIV-infected rhesus macaques to describe the feasibility of the modeling and resultant immunological changes. Three SIV-infected, clinically healthy macaques became HSV-1-infected by inoculation with 4 × 108 pfu HSV-1 McKrae on buccal, tongue, gingiva, and tonsils after gentle abrasion. HSV-1 DNA was shed in oral swabs for up to 21 days, and shedding recurred in association with intra-oral lesions after periods of no shedding during 56 days of follow up. HSV-1 DNA was detected in explant cultures of trigeminal ganglia collected at euthanasia on day 56. In the macaque with lowest baseline SIV viremia, SIV plasma RNA increased following HSV-1 infection. One macaque exhibited an acute pro-inflammatory response, and all three animals experienced T cell activation and mobilization in blood. However, T cell and antibody responses to HSV-1 were low and atypical. Through rigorous assessesments, this study finds that the virulent HSV-1 strain McKrae resulted in a low level HSV-1 infection that elicited modest immune responses and transiently modulated SIV infection.

  11. Comparison between experimental and predicted specific absorption rate of functionalized iron oxide nanoparticle suspensions

    Energy Technology Data Exchange (ETDEWEB)

    Yuan Yuan [Mechanical, Aerospace and Nuclear Engineering Department Rensselaer Polytechnic Institute, Troy, NY 12180 (United States); Tasciuc, Diana-Andra Borca, E-mail: borcad@rpi.edu [Mechanical, Aerospace and Nuclear Engineering Department Rensselaer Polytechnic Institute, Troy, NY 12180 (United States)

    2011-10-15

    Radio-frequency heated magnetic nanoaparticle suspensions have potential applications in cancer hyperthermia. To optimize these systems for hyperthermia applications it is important to be able to predict how their heat generation or specific absorption rate (SAR) is influenced by various factors, including nanoparticle coating or functionalization and aggregation. However, at present it is unclear how well-existing models predict experimental SAR results. Direct comparisons between predicted and measured SAR are scarce, despite an abundance of works reporting on heat generation rate of various magnetic nanoparticles suspensions. The main objective of this paper is to experimentally assess the validity of current models for SAR and extract information on the effects of coating and aggregation on heat generation rate. In this context, AC susceptibility and magnetization of suspensions of uncoated particles, as well as particles with aminosilane and carboxymethyl-dextran functionalizations, were measured. These properties were then used to predict the heat generation rate in alternating magnetic field starting from first principles, which was then compared to measured SAR. It was found that experimental SAR agrees relatively well with predictions (by a factor of two) when using experimental susceptibility values for the SAR calculation. However, for uncoated and amine-functionalized particles poor agreement (more than an order of magnitude difference) was found when the experimental susceptibility was substituted with predictions based on the Debye model. This apparent discrepancy is attributed to dipolar interactions between nanoparticles within aggregates in these samples, which enhances the imaginary part of the susceptibility and, consequently, the SAR values. The results also suggest that the thermal resistance effect of the coating has little influence on the SAR. - Highlights: > Thermal resistance of nanoparticle coating has little impact on heat dissipation

  12. Key metalloproteinases are expressed by specific cell types in experimental autoimmune encephalomyelitis

    DEFF Research Database (Denmark)

    Toft-Hansen, Henrik; Nuttall, Robert K; Edwards, Dylan R

    2004-01-01

    animal model, experimental autoimmune encephalomyelitis (EAE). We used real-time RT-PCR to profile the expression of all 22 known mouse MMPs, seven ADAMs, and all four known TIMPs in spinal cord from SJL/J mice and mice with adoptively transferred myelin basic protein (MBP)-specific EAE. A significant...... cellular sources of these strongly affected proteins in the inflamed CNS, we isolated macrophages, granulocytes, microglia, and T cells by cell sorting from the CNS of mice with EAE and analyzed their expression by real-time RT-PCR. This identified macrophages as a major source of MMP-12 and TIMP-1...

  13. Cholinesterase as inflammatory markers in a experimental infection by Trypanosoma evansi in rabbits

    Directory of Open Access Journals (Sweden)

    Márcio M. Costa

    2012-12-01

    Full Text Available The aim of this study is to evaluate the role of cholinesterases as an inflammatory marker in acute and chronic infection by Trypanosoma evansi in rabbits experimentally infected. Twelve adult female New Zealand rabbits were used and divided into two groups with 6 animals each: control group (rabbits 1-6 and infected group (rabbits 7-12. Infected group received intraperitoneally 0.5 mL of blood from a rat containing 108 parasites per animal. Blood samples used for cholinesterases evaluation were collected on days 0, 2, 7, 12, 27, 42, 57, 87, 102 and 118 days post-inoculation (PI. Increased activity (P0.05 was observed in the encephalic structures. The increased activities of AChE and BChE probably have a pro-inflammatory purpose, attempting to reduce the concentration of acetylcholine, a neurotransmitter which has an anti-inflammatory property. Therefore, cholinesterase may be inflammatory markers in infection with T. evansi in rabbits.O objetivo do presente estudo é avaliar o papel das colinesterases como marcadores inflamatórios nas fases aguda e crônica da infecção por T. evansi em coelhos infectados experimentalmente. Foram utilizados 12 coelhos adultos, fêmeas, da raça Nova Zelândia, divididos em dois grupos: um grupo controle, com seis animais (coelhos 1-6, e um grupo infectado, com seis animais (coelhos 7-12. Os animais pertencentes ao grupo infectados receberam, pela via intraperitoneal, 0,5 mL de sangue de rato contendo 108 tripanossomas por animal. Amostras do sangue utilizado para avaliação das colinesterases foram coletadas nos dias 0, 2, 7, 12, 27, 42, 57, 87, 102 e 118 pós-inoculação (PI. Aumento (P0,05 foi observada nas estruturas encefálicas. O aumento de atividade da AChE e BChE provavelmente tenha finalidade pró-inflamatória, a fim de reduzir as concentrações de acetilcolina, neurotransmissor que apresenta propriedade anti-inflamatória. Portanto, as colinesterases podem ser marcadores inflamatórios na infec

  14. [Immune response and reproductive consequences in experimentally infected ewes with Brucella ovis during late pregnancy].

    Science.gov (United States)

    Paolicchi, Fernando A; Nuñez, Marta; Fiorentino, María A; Malena, Rosana C; Trangoni, Marcos; Cravero, Silvio; Estein, Silvia M

    2013-01-01

    Ovine brucellosis by Brucella ovis is a highly prevalent disease in Argentina. This study aimed to evaluate the pathogenicity of B. ovis and the serological response in ewes during late pregnancy and in their offspring. Six adult ewes were distributed in two groupsG1 (pregnant females, n = 4) and G2 (nonpregnant females, n = 2). Three pregnant ewes at 15 days prepartum and one nonpregnant eve were inoculated with B. ovis. Sera of sheep and their offspring were analyzed by different serological tests. Samples of cervicovaginal mucus, placenta and milk were studied by bacteriology. A Brucella genus-specific PCR assay was carried out in placenta and milk samples. Placenta samples were hystopathologically processed. g1 females gave birth to live lambs, but one died hours postpartum. Serological techniques employed detected antibodies in serum of inoculated pregnant animal 5 days postchallenge. sera of female controls G1 and G2 remained negative throughout the study. Cervicovaginal mucus of infected ewes in G1 and G2 yielded negative results to bacteriology, but B. ovis was isolated from milk. The PCR assay was positive for the placenta and milk from inoculated pregnant ewes. Histopathology revealed necrotic suppurative placentitis in one placenta. However, although results demonstrated that B. ovis can invade the placenta and mammary gland, this bacterium did not cause abortion when it was inoculated intravenously at 15 days prepartum. B. ovis infection induced an early humoral response in pregnant ewes, but their lambs remained seronegative, indicating that there was no transfer of antibodies in infancy. Placenta colonization and milk excretion of B. ovis involves a potential source of infection for lambs, which could play a role as latent carriers of infection.

  15. Features of pathology in mice experimentally infected with highly pathogenic H5N1 influenza virus

    International Nuclear Information System (INIS)

    Ryabchikova, E. I.; Taranov, O. S.; Malkova, E. M.; Gritsyk, O. B.; Demina, O. K.

    2009-01-01

    Avian influenza became a new threat and has set people thinking about possibility of new influenza pandemic which may be caused by highly pathogenic H5N1 influenza virus. The virus could acquire ability of fast spreading between the humans and new pandemics could kill millions. Influenza virus H5N1 exhibited its deadly essence by taking out many millions of birds in nature and aviculture; other millions of chicks and ducks were killed to prevent spread of the epizootic. The strains isolated in Russia belong to Qinghai group of H5N1 influenza virus, and were imported to Russia by migratory birds. We examined time-course changes in mice blood and lungs after intranasal infection with strains A /Chicken/ Kurgan/ 05/2005, A/ Duck/ Kurgan/08/ 2005 and A/ Chicken/ Suzdalka/ Nov-11/2005 differing in virulence for this animal species. Development of leucopenia and severe damage of hemopoiesis were found in mice infected with all H5N1 influenza virus strains. Pathological changes in mice lungs during the infection with above mentioned strains, and strain-specific features have been examined. Main characteristics of lung pathology in all mice were focal nature of the alterations, severe damage of bronchial epithelium and pronounced alteration of lung vasculature. Strain A/Chicken/Suzdalka/Nov-11/2005 induced massive apoptosis of infected bronchial cells which may be a part of mechanism responsible for avirulent properties of this strain. The most interesting finding was absence of serious direct virus damage of the lung evidencing for principal role of the host humoral mechanisms in pathogenesis of H5N1 influenza in mice.(author)

  16. Sex-specific effects of TLR9 promoter variants on spontaneous clearance of HCV infection.

    Science.gov (United States)

    Fischer, Janett; Weber, Alexander N R; Böhm, Stephan; Dickhöfer, Sabine; El Maadidi, Souhayla; Deichsel, Danilo; Knop, Viola; Klinker, Hartwig; Möller, Bernd; Rasenack, Jens; Wang, Lisa; Sharma, Manu; Hinrichsen, Holger; Spengler, Ulrich; Buggisch, Peter; Sarrazin, Christoph; Pawlita, Michael; Waterboer, Tim; Wiese, Manfred; Probst-Müller, Elsbeth; Malinverni, Raffaele; Bochud, Pierre-Yves; Gardiner, Clair; O'Farrelly, Cliona; Berg, Thomas

    2017-10-01

    As pathogen sensors, Toll-like receptors (TLR) play a role in the first defence line during HCV infection. However, the impact of the DNA sensor TLR9 on the natural course of HCV infection is unknown. To address this, TLR9 promoter polymorphisms (single nucleotide polymorphisms (SNPs)) rs187084 and rs5743836 were investigated for their effect on disease progression. Therefore, the TLR9 SNPs and the interferon lambda 4 ( IFNL4 ) rs12979860 were genotyped in chronically HCV type 1 infected (n=333), in patients who spontaneously cleared the infection (n=161), in the Swiss HCV cohort (n=1057) and the well-characterised German (n=305) and Irish (n=198) 'anti-D' cohorts. Functional analyses were done with promoter reporter constructs of human TLR9 in B cells and assessing TLR9 mRNA levels in whole blood of healthy volunteers. The TLR9 rs187084 C allele was associated with spontaneous virus clearance in women of the study cohort (OR=2.15 (95% CI 1.18 to 3.90) p=0.012), of the Swiss HCV cohort (OR=2.06 (95% CI 1.02 to 4.18) p=0.044) and in both 'anti-D' cohorts (German: OR=2.01 (95% CI 1.14 to 3.55) p=0.016; Irish: OR=1.93 (95% CI 1.10 to 3.68) p=0.047). Multivariate analysis in the combined study and Swiss HCV cohorts supported the results (OR=1.99 (95% CI 1.30 to 3.05) p=0.002). Functional analyses revealed higher transcriptional activities for both TLR9 variants and an association of the C allele of rs5743836 with allele-specific TLR9 mRNA regulation by oestrogens in women. TLR9 promoter SNPs are associated with the natural course of HCV infection and show higher transcriptional activities. Our results imply the DNA sensor TLR9 in natural immunity against the RNA virus, HCV. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  17. Competitive Enzyme-Linked Immunosorbent Assay Based on a Rhoptry-Associated Protein 1 Epitope Specifically Identifies Babesia bovis-Infected Cattle

    Science.gov (United States)

    Goff, Will L.; McElwain, Terry F.; Suarez, Carlos E.; Johnson, Wendell C.; Brown, Wendy C.; Norimine, Junzo; Knowles, Donald P.

    2003-01-01

    The competitive enzyme-linked immunosorbent assay (cELISA) format has proven to be an accurate, reliable, easily standardized, and high-throughput method for detecting hemoparasite infections. In the present study, a species-specific, broadly conserved, and tandemly repeated B-cell epitope within the C terminus of the rhoptry-associated protein 1 of the hemoparasite Babesia bovis was cloned and expressed as a histidine-tagged thioredoxin fusion peptide and used as antigen in a cELISA. The assay was optimized with defined negative and positive bovine sera, where positive sera inhibited the binding of the epitope-specific monoclonal antibody BABB75A4. The cELISA accurately differentiated animals with B. bovis-specific antibodies from uninfected animals and from animals with antibodies against other tick-borne hemoparasites (98.7% specificity). In addition, B. bovis-specific sera from Australia, Argentina, Bolivia, Puerto Rico, and Morocco inhibited the binding of BABB75A4, confirming conservation of the epitope. The assay first detected experimentally infected animals between 13 and 17 days postinfection, and with sera from naturally infected carrier cattle, was comparable to indirect immunofluorescence (98.3% concordance). The assay appears to have the characteristics necessary for an epidemiologic and disease surveillance tool. PMID:12522037

  18. A Novel Benzodiazepine Compound Inhibits Yellow Fever Virus Infection by Specifically Targeting NS4B Protein.

    Science.gov (United States)

    Guo, Fang; Wu, Shuo; Julander, Justin; Ma, Julia; Zhang, Xuexiang; Kulp, John; Cuconati, Andrea; Block, Timothy M; Du, Yanming; Guo, Ju-Tao; Chang, Jinhong

    2016-09-21

    -risk regions. It has been estimated that up to 1.7 million YFV infections occur in Africa each year, resulting in 29,000 to 60,000 death. Thus far, there is no specific antiviral treatment for yellow fever. To cope with this medical challenge, we identified a benzodiazepine compound that selectively inhibits YFV by targeting the viral NS4B protein. To our knowledge, this is the first report demonstrating in vivo safety and antiviral efficacy of an YFV NS4B inhibitor in an animal model. We have thus reached a critical milestone toward the development of specific antiviral therapeutics for clinical management of yellow fever. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  19. Herd specific risk factors for Mycoplasma hyopneumoniae infections in suckling pigs at the age of weaning.

    Science.gov (United States)

    Nathues, Heiko; Woeste, Henrike; Doehring, Stefanie; Fahrion, Anna S; Doherr, Marcus G; Beilage, Elisabeth grosse

    2013-04-12

    Mycoplasma hyopneumoniae is the etiologic agent of enzootic pneumonia mainly occurring in fattening pigs. It is assumed that horizontal transmission of the pathogen during nursery and growing phase starts with few suckling pigs vertically infected by the sow. The aim of the present study was the exploration of the herd prevalence of M. hyopneumoniae infections in suckling pigs followed by an investigation of various herd specific factors for their potential of influencing the occurrence of this pathogen at the age of weaning. In this cross-sectional study, 125 breeding herds were examined by taking nasal swabs from 20 suckling pigs in each herd. In total, 3.9% (98/2500) of all nasal swabs were tested positive for M. hyopneumoniae by real-time PCR. Piglets tested positive originated from 46 different herds resulting in an overall herd prevalence of 36.8% (46/125) for M. hyopneumoniae infection in pigs at the age of weaning. While the herds were epidemiologically characterized, the risk for demonstration of M. hyopneumoniae was significantly increased, when the number of purchased gilts per year was more than 120 (OR: 5.8), and when the number of farrowing pens per compartment was higher than 16 (OR: 3.3). In herds with a planned and segregated production, where groups of sows entered previously emptied farrowing units, the risk for demonstration of M. hyopneumoniae in piglets was higher in herds with two or four weeks between batches than in herds with one or three weeks between batches (OR: 2.7). In this cross-sectional study, several risk factors could be identified enhancing the probability of breeding herds to raise suckling pigs already infected with M. hyopneumoniae at the time of weaning. Interestingly, some factors (farrowing rhythm, gilt acclimatisation issues) were overlapping with those also influencing the seroprevalences among sows or the transmission of the pathogen between older age groups. Taking the multifactorial character of enzootic pneumonia

  20. The effect of fermentable carbohydrates on experimental swine dysentery and whip worm infections in pigs

    DEFF Research Database (Denmark)

    Thomsen, Lisbeth E.; Knudsen, Knud Erik Bach; Jensen, Tim Kåre

    2007-01-01

    ingredients were composed. Both diets were based on triticale and barley and supplemented with either rape seed cake (Diet 1) or dried chicory root and sweet lupins (Diet 2). The study had a three-factorial design, with eight groups of pigs receiving Diet I or Diet 2, +/- B. hyodysenteriae, and +/- T suis......An experiment was conducted to study the effect of diets with contrasting fermentability in the large intestine on experimental infections with Brachyspira hyodysenteriae, the causative agent of swine dysentery, and the whip worm, Trichuris suis, in pigs. Two diets with organically grown....... Pigs fed Diet 2 and challenged with B. hyodysenteriae did not develop swine dysentery and B. hyodysenteriae was not demonstrated in any of the pigs during the study. In contrast, 94% of the B. hyodysenteriae challenged pigs fed Diet I showed clinical symptoms of swine dysentery and all the pigs were...

  1. Evaluation of tulathromycin for the treatment of pneumonia following experimental infection of swine with Mycoplasma hyopneumoniae.

    Science.gov (United States)

    McKelvie, Jo; Morgan, Jeremy H; Nanjiani, Ian A; Sherington, John; Rowan, Tim G; Sunderland, Simon J

    2005-01-01

    Tulathromycin was evaluated in the treatment of pneumonia in weaned pigs inoculated intranasally with Mycoplasma hyopneumoniae. Five days postchallenge, the pigs were randomized to treatment with a single IM administration of saline, a single IM administration of tulathromycin (2.5 mg/kg; day 0), or three IM administrations of enrofloxacin (5.0 mg/kg; days 0, 1, 2). Pigs were necropsied on day 12 or 13. Unchallenged controls remained healthy with no lung pathology. Compared with saline, coughing, mean lung lesion score, and proportional lung weight were significantly reduced and weight gain was significantly greater for tulathromycin-treated pigs (P pigs (P treatment of pneumonia following experimental infection with M. hyopneumoniae.

  2. Experimental infection of the bat tick Carios fonsecai (Acari: Ixodidae with the rabies virus

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    Silvana Regina Favoretto

    2013-12-01

    Full Text Available Introduction This study assessed the viability of the rabies virus in the argasid tick Carios fonsecai following experimental infection. Methods The mouse inoculation test (MIT, fluorescent antibody test (FAT and polymerase chain reaction (PCR were used. The rabies virus was administered to ticks via the intra-coelomic route, and the ticks were sacrificed at different time points. Results The inoculated ticks were negative for rabies according to the MIT. Ticks macerated with rabies virus were positive according to the MIT and FAT. All of the tick lots tested by PCR were positive. Conclusions The rabies virus became unviable shortly after its inoculation into tick bodies. Ticks are not likely to play an important role in the epidemiology of rabies.

  3. Laboratory experimental infection of sheep to Ornithobilharzia turkestanicum and its confirmation using post-mortem examination and histopathology

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    gholamreza karimi

    2014-11-01

    Full Text Available Ornithobilharzia turkestanicum from genus Ornithobilharzia genus and family Schistosomatidae is an important agent of parasitological infection in sheep. This parasite has been reported from Russia, China, Turkestan (Kazakhstan, Kyrgyzstan, Turkmenistan and Uzbekistan, Pakistan, Iraq, Turkey and Iran. Parasitological infection due to this agent could be one of the important factors of decreasing the production rate of livestock in Iran. The purpose of this study, was to experimentally infect sheep with this parasite and confirm the infection by post-mortem examination and Histopathology which was done successfully. Twenty five sheep were used in the study of which 10 sheep were experimentally infected by Ornithobilharzia turkestanikum using subcutaneous injection and 10 sheep by skin contact method and the other 5 sheep were kept as control. Result of post-mortem and Histopathology during a one year period confirmed that all of sheep were infected and adult worm, were seen in their mesentery. Mean number of cercaria used for inducing the infection was 6425 and 462 adult worms were collected post-mortem. There was no significant relationship between the number of cercaria and adult worms collected. Male sheep were more infected than female.

  4. Pharmacokinetic/Pharmacodynamic Profiles of Tiamulin in an Experimental Intratracheal Infection Model of Mycoplasma gallisepticum.

    Science.gov (United States)

    Xiao, Xia; Sun, Jian; Yang, Tao; Fang, Xi; Cheng, Jie; Xiong, Yan Q; Liu, Ya-Hong

    2016-01-01

    Mycoplasma gallisepticum is the most important pathogen in poultry among four pathogenic Mycoplasma species. Tiamulin is a pleuromutilin antibiotic that shows a great activity against M. gallisepticum and has been approved for use in veterinary medicine particularly for poultry. However, the pharmacokinetic/pharmacodynamics (PK/PD) profiles of tiamulin against M. gallisepticum are not well understood. Therefore, in the current studies, we investigated the in vivo PK/PD profiles of tiamulin using a well-established experimental intratracheal infection model of M. gallisepticum. The efficacy of tiamulin against M. gallisepticum was studied in 8-day-old chickens after intramuscular (i.m.) administration at 10 doses between 0-80 mg/kg. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to evaluate the PK parameters of tiamulin following i.m. administration at doses of 5, 40, and 80 mg/kg in Mycoplasma gallisepticum-infected neutropenic chickens. Real-time PCR (RT-PCR) was used for quantitative detection of M. gallisepticum. The MIC of tiamulin against M. gallisepticum strain S6 was 0.03 μg/mL. The PK/PD index, AUC24h/MIC, correlated well with the in vivo antibacterial efficacy. The in vivo data suggest that animal dosage regimens should supply AUC24h/MIC of tiamulin of 382.68 h for 2 log10 ccu equivalents M. gallisepticum reduction. To attain that goal, the administered dose is expected to be 45 mg/kg b.w. for treatment of M. gallisepticum infection with an MIC90 of 0.03 μg/mL.

  5. Pharmacokinetic/Pharmacodynamic Profiles of Tiamulin in an Experimental Intratracheal Infection Model of Mycoplasma gallisepticum

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    Xia Xiao

    2016-09-01

    Full Text Available Mycoplasma gallisepticum is the most important pathogen in poultry among four pathogenic Mycoplasma species. Tiamulin is a pleuromutilin antibiotic that shows a great activity against M. gallisepticum and has been approved for use in veterinary medicine particularly for poultry. However, the Pharmacokinetic/Pharmacodynamics (PK/PD profiles of tiamulin against M. gallisepticum are not well understood. Therefore, in the current studies, we investigated the in vivo PK/PD profiles of tiamulin using a well-established experimental intratracheal infection model of M. gallisepticum. The efficacy of tiamulin against M. gallisepticum was studied in 8-day-old chickens after intramuscular (i.m. administration at 10 doses between 0-80 mg/kg. Liquid chromatography-tandem mass spectrometry (LC-MS/MS was used to evaluate the PK parameters of tiamulin following i.m. administration at doses of 5, 40 and 80 mg/kg in Mycoplasma gallisepticum infected neutropenic chickens. Real time PCR (RT-PCR was used for quantitative detection of M. gallisepticum. The MIC of tiamulin against M. gallisepticum strain S6 was 0.03 μg/mL. The PK/PD index, AUC24h/MIC, correlated well with the in vivo antibacterial efficacy. The in vivo data suggest that animal dosage regimens should supply AUC24h/MIC of tiamulin of 382.68 h for 2 log10 ccu equivalents M. gallisepticum reduction. To attain that goal, the administered dose is expected to be 45 mg/kg b.w. for treatment of M. gallisepticum infection with an MIC90 of 0.03 μg/mL.

  6. Experimental infection of Balb/c nude mice with Hepatitis E virus

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    Zhu Jianguo

    2009-06-01

    Full Text Available Abstract Background Several animal species can reportedly act as reservoirs for Hepatitis E virus (HEV, a zoonotic pathogen. HEV and antibody to the virus have been detected in a variety of animals including rodents. Pig and rat models for HEV have been established for HEV, but a nude mouse has not yet been developed. Methods Balb/c nude mice were inoculated with swine HEV, both orally and via intravenous injection to insure infection. Negative control and experimental contact-exposed groups of mice were also included in the study. The liver, spleen, kidney, jejunum, ileum, cecum and colon of each mouse from all three groups were collected for reverse transcription nested polymerase chain reaction (RT-nPCR detection, indirect immunofluorescence observation and histopathologic examination. The sera from nude mice were tested for anti-HEV IgG by enzyme linked immunosorbent assay (ELISA. Activities of liver enzymes, including alanine aminotransferase (ALT, aspartate aminotransferase (AST and alkaline phosphatase (ALP, as well as total bilirubin (TBIL were also measured in the sera of the nude mice. Results HEV antigens and HEV RNA were detected in liver, spleen, kidney, jejunum, ileum and colon both by indirect immunofluorescence and by RT-nPCR in all of the inoculated and in one of the contact-exposed nude mice. Histopathological changes were observed in the liver and spleen of these mice. Infected mice showed increased levels of AST, ALP, and anti-HEV IgG in sera. The livers of contact-exposed mice showed obvious histopathological damage. Conclusion Nude mice could be readily infected by HEV isolated from pigs. The nude mouse may therefore be a useful animal model for studying the pathogenesis of HEV.

  7. Human rhinovirus in experimental infection after peroral Lactobacillus rhamnosus GG consumption, a pilot study.

    Science.gov (United States)

    Tapiovaara, Laura; Kumpu, Minna; Mäkivuokko, Harri; Waris, Matti; Korpela, Riitta; Pitkäranta, Anne; Winther, Birgit

    2016-08-01

    Data has emerged on possible beneficial effects of probiotics in respiratory tract viral infections, but it is unclear if the promising positive effects evidenced are due to a reduced viral load during infections. The aims of this work were to investigate the effect of peroral probiotic Lactobacillus rhamnosus GG (American Type Culture Collection [ATCC], Accession No. 53103) consumption on human rhinovirus (HRV) load in nasopharyngeal lavage samples in experimental HRV infection, and to correlate viral load to clinical symptoms. Intranasal HRV A39 inoculation was performed on 59 adults, who had consumed juice enriched with live or heat-inactivated L. rhamnosus GG or control juice for 3 weeks prior to inoculation in a randomized, controlled, pilot trial setting. Nasopharyngeal lavage samples and symptom data were analyzed on day 0 before inoculation, and on days 2 and 5. Samples were subjected to quantitative HRV detection by polymerase chain reaction (PCR). Before inoculation 9 of 59 (15%) samples presented with another HRV strain than the studied A39. There was a tendency toward the lowest HRV loads in the L. rhamnosus GG groups and the highest in placebo group (log10 copies/mL, 95% confidence interval [CI], 6.20 [5.18 to 7.40] in live, 6.30 [4.91 to 7.08] in inactivated L. rhamnosus GG, and 7.25 [5.81 to 7.52] in placebo group, p = 0.57 in day 2) in the wild-type excluded population. The HRV load positively correlated with the symptom scores on days 2 and 5 (correlation coefficient 0.61 [p rhamnosus GG when compared to placebo. HRV load positively correlated with the total symptom scores. © 2016 ARS-AAOA, LLC.

  8. Avian metapneumovirus subtype B experimental infection and tissue distribution in chickens, sparrows, and pigeons.

    Science.gov (United States)

    Gharaibeh, S; Shamoun, M

    2012-07-01

    Avian metapneumovirus (aMPV) is a respiratory virus that infects a range of avian hosts, including chickens and turkeys. Migratory and local wild birds are implicated in aMPV spread among farms, countries, and seasonal outbreaks of the disease. A subtype B aMPV isolate from commercial chicken flocks suffering from respiratory disease was experimentally inoculated oculonasally into 7-week old chickens, young pigeons, and sparrows. Chickens showed minimal tracheal rales, whereas pigeons and sparrows were asymptomatic. Shedding of aMPV was detected by reverse transcription polymerase chain reaction on homogenates from nasal turbinates. At 5 days postinfection, 5 of 5 chickens, 2 of 5 pigeons, and 1 of 5 sparrows were positive; at 10 or 15 days, none were positive. At 2 and 5 days, aMPV antigens were localized at the ciliated boarder of respiratory epithelium in nasal cavity and trachea of chickens, as well as to the conjunctival epithelium. Pigeons had detectable viral antigens in only the trachea at 2 and 5 days; sparrow tissues did not show any positive staining. At the end of the experiment, at 21 days postinfection, 14 of 15 inoculated chickens seroconverted against aMPV, but none of the inoculated pigeons or sparrows did. The authors believe that pigeons and sparrows have the ability to transmit the virus between chicken farms, although they do not consider pigeons and sparrows as natural hosts for aMPV, given that they failed to seroconvert. In conclusion, pigeons and sparrows are partially susceptible to aMPV infection, probably acting more as mechanical vectors because infection is only temporary and short-lived.

  9. Immunologic and hematologic responses in ponies with experimentally induced Strongylus vulgaris infection.

    Science.gov (United States)

    Bailey, M; Martin, S C; Lloyd, S

    1989-08-01

    Immunologic and hematologic responses were examined in 4 ponies with experimentally induced Strongylus vulgaris infection and in 5 helminth-free ponies. Two ponies were inoculated with 200 larvae and 2 were inoculated with 700 larvae of S vulgaris and then were reinoculated with the same numbers of larvae 34 weeks later. Initial response of the ponies inoculated with S vulgaris was S vulgaris antigen-induced lymphocyte response that developed 1.5 to 3 weeks after inoculation and did not persist. Development of antigen-reactive lymphocytes was followed sequentially by a biphasic complement-fixing antibody response, then biphasic eosinophilia. Antibody titer to S vulgaris antigen was higher in ponies inoculated with 700 larvae, compared with that in ponies given 200 larvae of S vulgaris. Also, the second peak in antibody titer and in absolute number of eosinophils was observed earlier in ponies inoculated with 700 larvae, compared with ponies inoculated with 200 S vulgaris larvae, and subsided before or from about 24 weeks after inoculation. The prepatent period for S vulgaris infection was 24 to 25 weeks. After reinoculation with S vulgaris, a degree of increased lymphocyte responsiveness was apparent but, by 17 weeks after reinoculation, only the primary peak in the absolute number of eosinophils indicated an anamnestic response. Essentially, antibody was not detectable after reinoculation.

  10. EXPERIMENTAL INFECTION WITH Toxocara cati IN PIGS: MIGRATORY PATTERN AND PATHOLOGICAL RESPONSE IN EARLY PHASE

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    Irma Estela Sommerfelt

    2014-07-01

    Full Text Available Experimental inoculations of approximately 100,000 infective Toxocara cati larval eggs were done in twelve pigs. The T. cati eggs used for inoculation were collected from cat's feces. Another group of three pigs served as an uninfected control. Groups of infected pigs were euthanized at seven, 14, 21, and 28 days post-inoculation (dpi. Tissue samples were taken for digestion and histopathology changes in early phase. The number of larvae recovered from the lungs peaked at seven and 14 dpi and were also present at 21, and 28 dpi. Larvae of T. cati were present in the lymph nodes of the small and large intestine at seven, 14, and 28 dpi and at seven, 14, 21, and 28 dpi respectively. In other studied tissues, no larvae or less than one larva per gram was detected. The pathological response observed in the liver and lungs at seven and 14 dpi, showed white spots on the liver surface and areas of consolidation were observed in the lungs. The lungs showed an inflammatory reaction with larvae in center at 28 dpi. In the liver we observed periportal and perilobular hepatitis. The lymph nodes of the intestines displayed eosinophil lymphadenitis with reactive centers containing parasitic forms in some of them. The granulomatous reaction was not observed in any tissues. The role of the other examined tissues had less significance. The relevance of this parasite as an etiological agent that leads to disease in paratenic hosts is evident.

  11. Clinical and Histopathological Evaluation of Terbinafine Treatment in Cats Experimentally Infected with Microsporum canis

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    T. Kotnik

    2006-01-01

    Full Text Available The efficacy of terbinafine hydrochloride (Lamisil©, Novartis in the treatment of 27 M. canis infected cats was followed. Treatment was started on the 17th day post inoculation (p.i., when successful experimental infection was proved. Nine cats were treated with low-dose terbinafine 10-20 mg/kg QD (LD group, nine cats were treated with high-dose terbinafine 30-40 mg/kg QD (HD group and nine were left untreated as a control group (C group. The efficacy of the treatment was evaluated using Wood's lamp examination, fungal culture and histopathology. All cats were positive 14 days p.i. Sixty days p.i. 8 cats from the LD group, 9 from the C group and 2 cats from the HD group had fungi in the tissue. Ninety days p.i. the HD group was free of fungi in the skin and other tests became negative on the 120th day p.i. Statistically significant differences were found between the HD group and both of the other groups (p M. canis yielded an inflammatory reaction of a mononuclear and neutrophil type in the cat skin. Hyperplastic interstitial dermatitis was a predominant tissue reaction although other types were also present during the study.

  12. The porcine acute phase protein response to acute clinical and subclinical experimental infection with Streptococcus suis

    DEFF Research Database (Denmark)

    Sørensen, Nanna Skall; Tegtmeier, C.; Andresen, Lars Ole

    2006-01-01

    The pig acute phase protein (APP) response to experimental Streptococcus suis (S. suis) infection was mapped by the measurement of the positive APPs C-reactive protein (CRP), serum amyloid A (SAA), haptoglobin (Hp) and major acute phase protein (pig-MAP) and the negative APPs albumin...... and apolipoprotein (Apo) A-I. The aim was to elucidate the differences in the acute phase behaviour of the individual APPs during a typical bacterial septicaemic, infection. Pigs were inoculated subcutaneously with live S. suis serotype 2 and blood was sampled before and on various days post inoculation (p...... the experiment with maximum levels around 10 times the day 0-levels, and pig-MAP was elevated on days 1-12 p.i. with peak levels of around seven times the day 0-levels. Apo A-I was decreased from days 1 to 8 and showed minimum levels of about 40% of day 0-levels around 1-2 days p.i. No clear pattern of changes...

  13. Peritoneum from Trypanosoma cruzi-infected mice is a homing site of Syndecan-1 neg plasma cells which mainly provide non-parasite-specific antibodies.

    Science.gov (United States)

    Merino, Maria C; Montes, Carolina L; Acosta-Rodriguez, Eva V; Bermejo, Daniela A; Amezcua-Vesely, Maria C; Gruppi, Adriana

    2010-05-01

    Humoral immunity during experimental Chagas disease has been considered a double-edge sword, critical to control Trypanosoma cruzi spreading but also associated to tissue damage. Peritoneal B-1 cells have been linked to the pathogenesis of Chagas disease; however, they may also help to control the infection by providing a fast wave of antibodies. In the present work, we determined that peritoneal B-cell response to T. cruzi is characterized by a marked reduction of CD19(+) B cells due to plasma cell differentiation rather than to cell death. Both peritoneal B-2 and B-1 cells decrease after parasite infection, but with different kinetics. Thus, the reduction in B-2 cell number can be detected from day 4 postinfection while the number of B-1 cells decreases only after 15 days of infection. Differentiation of peritoneal B-1 and B-2 cells into IgM-secreting cells was triggered by parasites but not by cytokines produced by peritoneal cells. Electron microscopy studies showed that peritoneum of infected mice lodges plasma cells with typical morphology as well as atypical plasma cells named 'Mott-like cells' containing high number of cytoplasmatic Ig(+) granules. The plasma cells induced during the infection showed a phenotype that may allow their persistence in peritoneum and they may contribute to the high levels of antibodies exhibited at the chronic phase of infection. We also showed that the peritoneal B-cell response is scarcely specific for the invading pathogen and rather constitute an important source of non-parasite-specific IgM and IgG in the infected host.

  14. Antibody Responses of Cervids (Cervus elaphus) following Experimental Mycobacterium bovis Infection and the Implications for Immunodiagnosis ▿

    Science.gov (United States)

    Harrington, Noel P.; Surujballi, Om P.; Prescott, John F.; Duncan, J. Robert; Waters, W. Ray; Lyashchenko, Konstantin; Greenwald, Rena

    2008-01-01

    Captive and free-ranging wildlife animals are implicated in the maintenance and transmission of bovine tuberculosis and therefore pose a significant obstacle to eradication of the disease from domestic livestock. The current antemortem diagnostic method, the intradermal tuberculin skin test, is impractical for routine use with many wild animals. Antibody-based assays are particularly attractive because the animals are handled only once and immediate processing of the sample is not required. This report characterizes the antibody responses of red deer-elk hybrids (Cervus elaphus) against Mycobacterium bovis and subsequently evaluates the diagnostic performance of select antigens in a rapid-test format. Sequential serum samples were collected from 10 animals experimentally infected with M. bovis and 5 noninfected animals over a 7-month period postinfection (p.i.). Samples were evaluated by enzyme-linked immunosorbent assays, immunoblot analyses, and multiantigen print immunoassays for seroreactivity to mycobacterial antigens. Although all infected animals produced antibodies to M. bovis protein antigens, there was significant animal-to-animal variation in the kinetics and magnitudes of responses and the antigens recognized. The most frequently recognized antigens included MPB83, ESAT-6, CFP10, and MPB70. Responses to some antigens, such as MPB83, were consistently detected as early as 4 weeks after inoculation, whereas other antigens were detected only much later (>140 days p.i.). Antibody responses were boosted by injection of tuberculin for intradermal tuberculin skin testing. Comparison of single-antigen (fluorescence polarization assay) with multiantigen (CervidTB STAT-PAK) rapid tests demonstrated that a highly sensitive and specific serodiagnostic test for tuberculosis in cervids will require multiple and carefully selected seroreactive antigens covering a broad spectrum of antibody specificities. PMID:18815233

  15. Specific and Non-Specific Factors of Humoral Immunity as Markers for Pregnancy Loss in Women with Cytomegalovirus Infection

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    Irina A. Andrievskaya

    2015-12-01

    Full Text Available The aim of this study was to estimate the changes in humoral immunity and their association with complications of pregnancy (spontaneous abortions, threatened miscarriage, premature birth depending on the gestational age and recurrence of cytomegalovirus infection (CMVI. A direct relationship between the frequency of detection of an anti-CMV IgG antibody titer of 1:1600 and the prevalence of acute respiratory disease during pregnancy has been identified. We found an imbalance in the production of the non-specific antibodies (an increase in the blood levels of total IgM and a decrease in IgA and IgG levels in the subgroup of women with relapsed CMVI at 6 to 8 weeks of gestation and spontaneous abortion, as well as in the subgroup of women with relapsed CMVI at 15 to 21 weeks of gestation and the risk of the late miscarriage, compared to those with relapsed CMVI at 9 to 14 weeks and 22 to 32 weeks of gestation. An increase in blood levels of total IgM and IgG and a decrease in IgA level was identified in the subgroup of women with relapsed CMVI at 9 to14 weeks of gestation and a threatened abortion, as well as in the subgroup of women with relapsed CMVI at 22 to 32 weeks of gestation and preterm birth. The obtained data of the imbalance in the primary and secondary immune response in CMV- seropositive pregnant women during relapsed CMVI indicate disturbances in the systemic and local intercellular interactions of immunocompetent cells, which lead to an imbalance in the production of antibodies involved in the elimination of viral agents and to the development of a systemic inflammatory response that complicates the course of pregnancy. CMVI relapse at 7 to 8 weeks of gestation is associated with reproductive losses; a risk for threatened miscarriage, threatened premature labor, and retrochorial hematoma increases significantly with CMVI relapse in the more remote gestational age.

  16. Lipid and glucose metabolism of broilers (Gallus gallus domesticus experimentally infected with Eimeria acervulina Tyzzer, 1929 oocysts

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    FLC Freitas

    2008-09-01

    Full Text Available Lipid and glucose metabolism of 76 ten-day-old Cobb male broilers, experimentally infected with Eimeria acervulina, was studied for 30 days. Birds were distributed in 2 groups: one infected with 1x10(6 E. acervulina sporulated oocysts, and the other inoculated with distilled water. Pathological e biochemical liver changes were assessed, as well as plasma glucose concentrations and total cholesterol, HDL, LDL, VLDL, fatty-acid, and triglyceride levels in the serum. The infected broilers presented hypoglycemia associated with a reduction in liver glycogen. In addition, these birds developed fatty liver, and there were changes in all lipid classes in the serum. Lipid and glucose metabolism was dramatically changed in broilers experimentally infected with 1x10(6 E. acervulina oocysts.

  17. Time course of gene expression profiling in the liver of experimental mice infected with Echinococcus multilocularis.

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    Renyong Lin

    Full Text Available BACKGROUND: Alveolar echinococcosis (AE is a severe chronic parasitic disease which behaves like a slow-growing liver cancer. Clinical observations suggest that the parasite, Echinococcus multilocularis (E. multilocularis influences liver homeostasis and hepatic cell metabolism. However, this has never been analyzed during the time course of infection in the common model of secondary echinococcosis in experimental mice. METHODOLOGY/PRINCIPAL FINDINGS: Gene expression profiles were assessed using DNA microarray analysis, 1, 2, 3 and 6 months after injection of E. multilocularis metacestode in the liver of susceptible mice. Data were collected at different time points to monitor the dynamic behavior of gene expression. 557 differentially expressed genes were identified at one or more time points, including 351 up-regulated and 228 down-regulated genes. Time-course analysis indicated, at the initial stage of E. multilocularis infection (month 1-2, that most of up-regulated pathways were related to immune processes and cell trafficking such as chemokine-, mitogen-activated protein kinase (MAPK signaling, and down-regulated pathways were related to xenobiotic metabolism; at the middle stage (month 3, MAPK signaling pathway was maintained and peroxisome proliferator-activated receptor (PPAR signaling pathway emerged; at the late stage (month 6, most of up-regulated pathways were related to PPAR signaling pathway, complement and coagulation cascades, while down-regulated pathways were related to metabolism of xenobiotics by cytochrome P450. Quantitative RT-PCR analysis of a random selection of 19 genes confirmed the reliability of the microarray data. Immunohistochemistry analysis showed that proliferating cell nuclear antigen (PCNA was increased in the liver of E. multilocularis infected mice from 2 months to 6 months. CONCLUSIONS: E. multilocularis metacestode definitely exerts a deep influence on liver homeostasis, by modifying a number of gene

  18. Acute phase response in two consecutive experimentally induced E. coli intramammary infections in dairy cows

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    Saatsi Johanna

    2008-06-01

    Full Text Available Abstract Background Acute phase proteins haptoglobin (Hp, serum amyloid A (SAA and lipopolysaccharide binding protein (LBP have suggested to be suitable inflammatory markers for bovine mastitis. The aim of the study was to investigate acute phase markers along with clinical parameters in two consecutive intramammary challenges with Escherichia coli and to evaluate the possible carry-over effect when same animals are used in an experimental model. Methods Mastitis was induced with a dose of 1500 cfu of E. coli in one quarter of six cows and inoculation repeated in another quarter after an interval of 14 days. Concentrations of acute phase proteins haptoglobin (Hp, serum amyloid A (SAA and lipopolysaccharide binding protein (LBP were determined in serum and milk. Results In both challenges all cows became infected and developed clinical mastitis within 12 hours of inoculation. Clinical disease and acute phase response was generally milder in the second challenge. Concentrations of SAA in milk started to increase 12 hours after inoculation and peaked at 60 hours after the first challenge and at 44 hours after the second challenge. Concentrations of SAA in serum increased more slowly and peaked at the same times as in milk; concentrations in serum were about one third of those in milk. Hp started to increase in milk similarly and peaked at 36–44 hours. In serum, the concentration of Hp peaked at 60–68 hours and was twice as high as in milk. LBP concentrations in milk and serum started to increase after 12 hours and peaked at 36 hours, being higher in milk. The concentrations of acute phase proteins in serum and milk in the E. coli infection model were much higher than those recorded in experiments using Gram-positive pathogens, indicating the severe inflammation induced by E. coli. Conclusion Acute phase proteins would be useful parameters as mastitis indicators and to assess the severity of mastitis. If repeated experimental intramammary

  19. Infecções experimentaes na Leishmaniose visceral americana Experimental infections in american visceral leishmaniasis

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    Aristides Marques da Cunha

    1938-01-01

    sôro-agglutinação, conforme mostramos em trabalho anterior, não permite a separação das especies do genero Leishmania, pois todas ellas, quando recentemente isoladas, possuem identica constituição antigenica, que se modifica depois, pela conservação longo tempo em cultura. É esse facto, que deu logar ás conclusões contradictorias a que chegaram os autores que se ocuparam do assumpto bem como os primeiros resultados que obtivemos. Deante de todos esses factos, nos julgamos autorizados a concluir como já fizemos anteriormente, que o agente da Leishmaniose visceral americana é identico á Leishmania infantum. Ao terminar, queremos deixar consignados nossos agradecimentos ao Dr. E. chagas, por ter posto a nossa disposição as culturas de Leishmania por elle isoladas, tornando possivel deste modo, a execução do presente trabalho.With cultures isolated from cases of american visceral leishmaniasis we succeeded in obtaining experimental infections in hamsters (Cricetus cricetus, rhesus monkeys (Macaca mullata and dogs. Hamsters were infected with strains obtained from man and dogs, the intraperitoneal way having been always employed. When cultures recently isolated are used, infection is obtained practically in 100% of the animals inoculated. The first negative results obtained by us may be explained by the use of cultures isolated some time before (about 7 months 0 and which had lost already their virulence. In some cases external lesions are observed represented by alterations of the skin and swelling of the paws. The skin lesions are observed on the ventral surface and consist in depilation, erythema and exudation. The skin thus affected shows to be extremely friable, rupturing at the movements of the animal when hold. On post-mortem examination, besides the lesions pointed out, the animals present enlargement of the spleen. The parasites are very numerous in the spleen, liver, bone marrow, etc. The changed skin shows considerable hypertrophy of the

  20. Transovarial Transmission of Rickettsia spp. and Organ-Specific Infection of the Whitefly Bemisia tabaci

    Science.gov (United States)

    Brumin, Marina; Levy, Maggie

    2012-01-01

    The whitefly Bemisia tabaci is a cosmopolitan insect pest that harbors Portiera aleyrodidarum, the primary obligatory symbiotic bacterium, and several facultative secondary symbionts. Secondary symbionts in B. tabaci are generally associated with the bacteriome, ensuring their vertical transmission; however, Rickettsia is an exception and occupies most of the body cavity, except the bacteriome. The mode of Rickettsia transfer between generations and its subcellular localization in insect organs have not been investigated. Using electron and fluorescence microscopy, we show that Rickettsia infects the digestive, salivary, and reproductive organs of the insect; however, it was not observed in the bacteriome. Rickettsia invades the oocytes during early developmental stages and resides in follicular cells and cytoplasm; it is mostly excluded when the egg matures; however, some bacterial cells remain in the egg, ensuring their transfer to subsequent generations. Rickettsia was localized to testicles and the spermatheca, suggesting a horizontal transfer between males and females during mating. The bacterium was further observed at large amounts in midgut cells, concentrating in vacuole-like structures, and was located in the hemolymph, specifically at exceptionally large amounts around bacteriocytes and in fat bodies. Organs further infected by Rickettsia included the primary salivary glands and stylets, sites of possible secretion of the bacterium outside the whitefly body. The close association between Rickettsia and the B. tabaci digestive system might be important for digestive purposes. The vertical transmission of Rickettsia to subsequent generations occurs via the oocyte and not, like other secondary symbionts, the bacteriome. PMID:22660706

  1. Antigen-specific H1N1 influenza antibody responses in acute respiratory tract infections and their relation to influenza infection and disease course.

    Science.gov (United States)

    Haran, John Patrick; Hoaglin, David C; Chen, Huaiqing; Boyer, Edward W; Lu, Shan

    2014-08-01

    Early antibody responses to influenza infection are important in both clearance of virus and fighting the disease. Acute influenza antibody titers directed toward H1-antigens and their relation to infection type and patient outcomes have not been well investigated. Using hemagglutination inhibition (HI) assays, we aimed to characterize the H1-specific antibody titers in patients with influenza infection or another respiratory infection before and after the H1N1-pandemic influenza outbreak. Among patients with acute influenza infection we related duration of illness, severity of symptoms, and need for hospitalization to antibody titers. There were 134 adult patients (average age 34.7) who presented to an urban academic emergency department (ED) from October through March during the 2008-2011 influenza seasons with symptoms of fever and a cough. Nasal aspirates were tested by viral culture, and peripheral blood serum was run in seven H1-subtype HI assays. Acutely infected influenza patients had markedly lower antibody titers for six of the seven pseudotype viruses. For the average over the seven titers (log units, base 2) their mean was 7.24 (95% CI 6.88, 7.61) compared with 8.60 (95% CI 8.27, 8.92) among patients who had a non-influenza respiratory illness, pinfection, titers of some antibodies correlated with severity of symptoms and with total duration of illness (pacute respiratory infections, lower concentrations of H1-influenza-specific antibodies were associated with influenza infection. Among influenza-infected patients, higher antibody titers were present in patients with a longer duration of illness and with higher severity-of-symptom scores. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Immune Reactions Against Elongation Factor 2 Kinase: Specific Pathogenesis of Gastric Ulcer from Helicobacter pylori Infection

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    Kiyoshi Ayada

    2009-01-01

    Full Text Available Helicobacter pylori (H. pylori infection is a definite causative factor for gastric ulcers (GUs. In the present study we detected a specific antigen of gastric epithelial cells (HGC-27 using cell ELISA, which was recognized by the sera of GU patients (n=20 but not in patients with chronic gastritis (CG; n=20 or in healthy volunteers (HC; n=10. This antigen was over-expressed by a stressful (heat-stressed environment, and was identified as elongation factor 2 kinase (EF-2K by western blotting. The GU patients' lymphocytes stimulated by H. pylori specifically disrupted heat-stressed HGC-27 cells in a cytotoxic assay. In flow cytometry, the effector cells (lymphocytes from GU patients were significantly differentiated to T helper type 1 lymphocyte (Th1 and cytotoxic T lymphocyte (CTL as opposed to those from CG patients. The target cells (HGC-27 expressed EF-2K and MHC-class I together with costimulatory molecules from heat stress. This antigen specific immune mechanism could have a prominent role in the pathogenesis of GU.

  3. The impact of pregnancy on the HIV-1-specific T cell function in infected pregnant women.

    Science.gov (United States)

    Hygino, Joana; Vieira, Morgana M; Kasahara, Taissa M; Xavier, Luciana F; Blanco, Bernardo; Guillermo, Landi V C; Filho, Renato G S; Saramago, Carmen S M; Lima-Silva, Agostinho A; Oliveira, Ariane L; Guimarães, Vander; Andrade, Arnaldo F B; Bento, Cleonice A M

    2012-12-01

    Evidences indicate that pregnancy can alter the Ag-specific T-cell responses. This work aims to evaluate the impact of pregnancy on the in vitro HIV-1-specific immune response. As compared with non-pregnant patients, lower T-cell proliferation and higher IL-10 production were observed in T-cell cultures from pregnant patients following addition of either mitogens or HIV-1 antigens. In our system, the main T lymphocyte subset involved in producing IL-10 was CD4(+)FoxP3(-). Depletion of CD4(+) cells elevated TNF-α and IFN-γ production. Interestingly, the in vitro HIV-1 replication was lower in cell cultures from pregnant patients, and it was inversely related to IL-10 production. In these cultures, the neutralization of IL-10 by anti-IL-10 mAb elevated TNF-α release and HIV-1 replication. In conclusion, our results reveal that pregnancy-related events should favor the expansion of HIV-1-specific IL-10-secreting CD4(+) T-cells in HIV-1-infected women, which should, in the scenario of pregnancy, help to reduce the risk of vertical HIV-1 transmission. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Infective larvae of five Onchocerca species from experimentally infected Simulium species in an area of zoonotic onchocerciasis in Japan

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    Fukuda M.

    2008-06-01

    Full Text Available Microfilariae of five Onchocerca species, O. dewittei japonica (the causative agent of zoonotic onchocerciasis in Oita, Kyushu, Japan from wild boar (Sus scrofa, O. skrjabini and O. eberhardi from sika deer (Cervus nippon, O. lienalis from cattle, and an as yet unnamed Onchocerca sp. from wild boar, were injected intrathoracically into newly-emerged black flies of several species from Oita to search the potential vector(s of these parasites and identify their infective larvae. Development of O. dewittei japonica microfilariae to the infective larvae occurred in Simulium aokii, S. arakawae, S. bidentatum, S. japonicum, S. quinquestriatum, and S. rufibasis while development of infective larvae of O. skrjabini, O. eberhardi, and the unnamed Onchocerca sp. was observed in S. aokii, S. arakawae, and S. bidentatum. Development of O. lienalis microfilaria to infective larvae occurred in S. arakawae. Based on the morphology of infective larvae obtained, we proposed a key of identification of Onchocerca infective larvae found in Oita. We also reconsider the identification of three types of infective larvae previously recovered from Simulium species captured at cattle sheds: the large type I larvae that may be an undescribed species; the small type III identified as O. lienalis may include O. skrjabini too; the intermediary type II that may be O. gutturosa, or O. dewittei japonica, or the unnamed Onchocerca sp. of wild boar.

  5. Experimental study of action of autostrains Aerococcus viridans on the model Pseudomonas infection

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    D. O. Stepanskyi

    2017-05-01

    Full Text Available The paper presents the results of a study of the action of Aerococcus autostrains on the model of a chronic blue pus infection. For the study of the action of Aerococcus autosymbiont strains on Pseudomonas aeruginosa, three of the most biochemically and antagonistically active isolates were selected: 1 5m2015 (isolated from mice; 2 3k2015 (isolated from rats; 3 3ch2015 (isolated from humans. Experiments were conducted on 84 white outbred mice weighing 16–17 g, 60 were used as the experimental, and 24 as the control group. In the experimental group of animals, infected wounds were treated by Aerococcus autosymbiont strains once daily (0.2 billion ml–1 till recovery. The drug was administered under the scab with a syringe. In the control animals the wound was treated by isotonic sodium chloride solution (concentration 0.9% with the same route of administration and for the same period of time. It was found that from the very first days of application of Aerococci autosymbiont strains, perifocal inflammation was less severe in most animals in the research group compared with the control group. Starting from the fourth day of usage of Aerococcus autosymbiont strains the number of pseudomonades, contained in secretions from wounds in the experimental group of mice was significantly lower than in the control animals. It was revealed that in case of application of Aerococcus strain (5m2015 isolated from mice, the animals had better indicators of recovery, dynamics of local clinical signs of inflammation and the number of pseudomonades contained in the wound in comparison with other Aerococcus autostrains isolated from rats and humans. The wounds purified from pus and covered with dry scab faster. For example, wounds completely healed with dry scab rejection by the 11th day of observation in 44 of 58 surviving mice (75.9%. In the control group a similar pattern was observed in only 3 of 17 mice (17.6% by that period. The number of Pseudomonas

  6. Pathogenesis and Immunohistochemical Studies of Caprine Pleuropneumonia in Experimentally Infected Goats

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    Umer Sadique*, Zafar Iqbal Chaudhry1, Muhammad Younus Rana2, Aftab Ahmad Anjum3, Zahoor-Ul-Hassan, Abdul Sajid and Muhammad Mushtaq

    2012-06-01

    Full Text Available This study was designed to evaluate the pathogenesis of caprine pleuropneumonia (CPP in the experimentally inoculated goats with Mycoplasma mycoides subspecies Capri (Mmc. For this purpose, 12 goats (Group B were inoculated with bacterial isolates of Mmc while four goats were kept as untreated control (Group A. Clinical signs of the disease were recorded twice daily. Two goats from group B were sacrificed on weekly basis to demonstrate gross pathological lesions in different organs. Tissue samples from lungs, trachea, liver, heart, kidney, spleen, and small intestines were preserved for histopathological studies. The lungs and lymph nodes were preserved to demonstrate the antigen in tissue by using immuno- histochemical technique. The disease was successfully reproduced in all infected goats with severe manifestation. The clinical signs and gross lesions of the disease were mild at the beginning and became severe at the third and fourth weeks and then progressed to moderate and chronic forms. The histopathological lesions characteristic of CPP were found in all the organs. Antigen of Mmc was detected in tissue sections of lungs and lymph nodes. In conclusion, the disease was efficiently reproduced in experimental animals that showed acute septicemic form with lethal outcome.

  7. Distribution patterns and predilection muscles of Trichinella zimbabwensis larvae in experimentally infected Nile crocodiles (Crocodylus niloticus Laurenti

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    Louis J. La Grange

    2014-02-01

    Full Text Available No controlled studies have been conducted to determine the predilection muscles of Trichinella zimbabwensis larvae in Nile crocodiles (Crocodylus niloticus or the influence of infection intensity on the distribution of the larvae in crocodiles. The distribution of larvae in muscles of naturally infected Nile crocodiles and experimentally infected caimans (Caiman crocodilus and varans (Varanus exanthematicus have been reported in literature. To determine the distribution patterns of T. zimbabwensis larvae and predilection muscles, 15 crocodiles were randomly divided into three cohorts of five animals each, representing high infection (642 larvae/kg of bodyweight average, medium infection (414 larvae/kg of bodyweight average and low infection (134 larvae/kg of bodyweight average cohorts. In the high infection cohort, high percentages of larvae were observed in the triceps muscles (26% and hind limb muscles (13%. In the medium infection cohort, high percentages of larvae were found in the triceps muscles (50%, sternomastoid (18% and hind limb muscles (13%. In the low infection cohort, larvae were mainly found in the intercostal muscles (36%, longissimus complex (27%, forelimb muscles (20% and hind limb muscles (10%. Predilection muscles in the high and medium infection cohorts were similar to those reported in naturally infected crocodiles despite changes in infection intensity. The high infection cohort had significantly higher numbers of larvae in the sternomastoid, triceps, intercostal, longissimus complex, external tibial flexor, longissimus caudalis and caudal femoral muscles (p < 0.05 compared with the medium infection cohort. In comparison with the low infection cohort, the high infection cohort harboured significantly higher numbers of larvae in all muscles (p < 0.05 except for the tongue. The high infection cohort harboured significantly higher numbers of larvae (p < 0.05 in the sternomastoid, triceps, intercostal, longissimus complex

  8. Collapse of Cytolytic Potential in SIV-Specific CD8+ T Cells Following Acute SIV Infection in Rhesus Macaques.

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    Emily R Roberts

    2016-12-01

    Full Text Available Poor maintenance of cytotoxic factor expression among HIV-specific CD8+ T cells, in part caused by dysregulated expression of the transcription factor T-bet, is associated with HIV disease progression. However, the precise evolution and context in which CD8+ T cell cytotoxic functions become dysregulated in HIV infection remain unclear. Using the rhesus macaque (RM SIV infection model, we evaluated the kinetics of SIV-specific CD8+ T cell cytolytic factor expression in peripheral blood, lymph node, spleen, and gut mucosa from early acute infection through chronic infection. We identified rapid acquisition of perforin and granzyme B expression in SIV-specific CD8+ T cells in blood, secondary lymphoid tissues and gut mucosa that collapsed rapidly during the transition to chronic infection. The evolution of this expression profile was linked to low expression of T-bet and occurred independent of epitope specificity, viral escape patterns and tissue origin. Importantly, during acute infection SIV-specific CD8+ T cells that maintained T-bet expression retained the ability to express granzyme B after stimulation, but this relationship was lost in chronic infection. Together, these data demonstrate the loss of cytolytic machinery in SIV-specific CD8+ T cells in blood and at tissue sites of viral reservoir and active replication during the transition from acute to chronic infection. This phenomenon occurs despite persistent high levels of viremia suggesting that an inability to maintain properly regulated cytotoxic T cell responses in all tissue sites enables HIV/SIV to avoid immune clearance, establish persistent viral reservoirs in lymphoid tissues and gut mucosa, and lead ultimately to immunopathogenesis and death.

  9. Gene-Specific-Candidate-Driven Study to decipher Genetic Predisposition to Rotavirus Infection

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    Kshitija Rane-Yadav

    2017-10-01

    Full Text Available Recent report of WHO shows 113000 children in India succumb to death due to Rotavirus diarrhea. Lack of knowledge about pathogenesis of virus has led to lack of therapy for severely infected patients. Previous studies have found that, animal rotavirus requires sialyl glycan moieties on cell surface for pathogenesis. Present study states that human rotaviruses also follows same path and this specificity of virus leads to host genetic predisposition for the infection as well as the disease. Two hundred children less than 5 years of age clinically suspected of viral diarrhea were screened for rotavirus infection. EDTA blood was processed for analyzing DNA sequences of various fucosyltransferase genes. Lewis antigens which are secretory form of ABO Histo Blood Group Antigens were correlated with the genotype of patient. Genetics of HBGA secretion, particularly, basis of Leb expression manifested by fucosyltransferase-2 enzyme was studied in healthy individuals and was compared in cases of rotavirus positive and negative diarrhea. Positive clinical isolates with various genotypes were purified from stool samples and gene for VP4 - surface spike protein was sequenced. Using Bioinformatics interphase, three dimensional protein structures were modeled and their functional domains were analyzed. All these modeled proteins were docked with Leb HBGA (Lewis-b Histo Blood Group Antigens using molecular docking software. In present study, to investigate possible association of the rotavirus with host genome, we screened highly suspected genes involved in expression of glycoproteins on enterocytes. This study performed for prevalent Indian strains of rotaviruses provides possible evidence that, VP8 domain of VP4 spike protein utilizes Leb surface antigen for attachment and entry to enterocytes in the intestine. The FUT2 and FUT3 gene has been found to show significant association with the rotavirus infection hence can serve as a biomarker for genetic

  10. Genomic characterization of H14 subtype Influenza A viruses in new world waterfowl and experimental infectivity in mallards (Anas platyrhynchos.

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    Andrew M Ramey

    Full Text Available Recent repeated isolation of H14 hemagglutinin subtype influenza A viruses (IAVs in the New World waterfowl provides evidence to suggest that host and/or geographic ranges for viruses of this subtype may be expanding. In this study, we used genomic analyses to gain inference on the origin and evolution of H14 viruses in New World waterfowl and conducted an experimental challenge study in mallards (Anas platyrhynchos to evaluate pathogenicity, viral replication, and transmissibility of a representative viral strain in a natural host species. Genomic characterization of H14 subtype IAVs isolated from New World waterfowl, including three isolates sequenced specifically for this study, revealed high nucleotide identity among individual gene segments (e.g. ≥95% shared identity among H14 HA gene segments. In contrast, lower shared identity was observed among internal gene segments. Furthermore, multiple neuraminidase subtypes were observed for H14 IAVs isolated in the New World. Gene segments of H14 viruses isolated after 2010 shared ancestral genetic lineages with IAVs isolated from wild birds throughout North America. Thus, genomic characterization provided evidence for viral evolution in New World waterfowl through genetic drift and genetic shift since purported introduction from Eurasia. In the challenge study, no clinical disease or lesions were observed among mallards experimentally inoculated with A/blue-winged teal/Texas/AI13-1028/2013(H14N5 or exposed via contact with infected birds. Titers of viral shedding for mallards challenged with the H14N5 IAV were highest at two days post-inoculation (DPI; however shedding was detected up to nine DPI using cloacal swabs. The distribution of viral antigen among mallards infected with H14N5 IAV was largely restricted to enterocytes lining the villi in the lower intestinal tract and in the epithelium of the bursa of Fabricius. Characterization of the infectivity of A/blue-winged teal/Texas/AI13

  11. Genomic characterization of H14 subtype influenza A viruses in New World waterfowl and experimental infectivity in mallards Anas platyrhynchos

    Science.gov (United States)

    Ramey, Andy M.; Poulson, Rebecca L.; Gonzalez-Reiche, Ana S.; Perez, Daniel R.; Stalknecht, David E.; Brown, Justin D.

    2014-01-01

    Recent repeated isolation of H14 hemagglutinin subtype influenza A viruses (IAVs) in the New World waterfowl provides evidence to suggest that host and/or geographic ranges for viruses of this subtype may be expanding. In this study, we used genomic analyses to gain inference on the origin and evolution of H14 viruses in New World waterfowl and conducted an experimental challenge study in mallards (Anas platyrhynchos) to evaluate pathogenicity, viral replication, and transmissibility of a representative viral strain in a natural host species. Genomic characterization of H14 subtype IAVs isolated from New World waterfowl, including three isolates sequenced specifically for this study, revealed high nucleotide identity among individual gene segments (e.g. ≥95% shared identity among H14 HA gene segments). In contrast, lower shared identity was observed among internal gene segments. Furthermore, multiple neuraminidase subtypes were observed for H14 IAVs isolated in the New World. Gene segments of H14 viruses isolated after 2010 shared ancestral genetic lineages with IAVs isolated from wild birds throughout North America. Thus, genomic characterization provided evidence for viral evolution in New World waterfowl through genetic drift and genetic shift since purported introduction from Eurasia. In the challenge study, no clinical disease or lesions were observed among mallards experimentally inoculated with A/blue-winged teal/Texas/AI13-1028/2013(H14N5) or exposed via contact with infected birds. Titers of viral shedding for mallards challenged with the H14N5 IAV were highest at two days post-inoculation (DPI); however shedding was detected up to nine DPI using cloacal swabs. The distribution of viral antigen among mallards infected with H14N5 IAV was largely restricted to enterocytes lining the villi in the lower intestinal tract and in the epithelium of the bursa of Fabricius. Characterization of the infectivity of A/blue-winged teal/Texas/AI13-1028/2013(H14N5) in

  12. The potential of methylethylpiridinol in treatment of bacterial infections caused by Klebsiella pneumoniae (experimental study

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    V. M. Brykhanov

    2016-01-01

    Full Text Available Aim. Investigated the activity of methylethylpiridinol (6-methyl-2-ethyl-pyridin-3-ol hydrochloride in the comprehensive treatment of the experimental bacterial infection caused by Klebsiella pneumoniae.Materials and methods. The study was conducted on clinical isolates of Klebsiella pneumoniae. At the first stage of the study (in vitro studied the effect of methylethylpiridinol in concentrations 0,25–4 mM on the growth of the strain and the activity of the sublethal concentrations of antibiotics – gentamicin, ciprofloxacin, tetracycline, ceftazidime. In the second stage of the study (in vivo in rats Wistar simulated bacterial peritonitis by intraperitoneal injection of a suspension of Klebsiella pneumoniae and investigated the effect of methylethylpiridinol (80 mg/kg on the effectiveness of antibiotic therapy with gentamicin (30 mg/kg, ciprofloxacin (50 mg/kg, ceftazidime (120 mg/kg or tetracycline (80 mg/kg. The animal blood plasma was determined ceruloplasmin concentration (marker of the intensity of infectious-inflammatory process and thiobarbiturate-jet products, erythrocytes – the concentration of reduced glutathione, catalase and glutathione peroxidase.Results. It is found that a methylethylpiridinol inhibits the development of periodic bacterial cultures, but exhibits a pronounced antagonism with respect to gentamicin. Antioxidant slightly increases the activity of ciprofloxacin and tetracycline. The bacteriostatic effect of antioxidant reduces the action of ceftazidime in vitro. In conditions of chemotherapy by using of gentamicin and ciprofloxacin additional injection of methylethylpiridinol leads to the preservation of ceruloplasmin level to the level of non-treated animals without showing the antioxidant effect. Ceftazidime exhibits antioxidant effect, reduces the introduction of methylethylpiridinol. The antioxidant properties of methylethylpiridinol did not appear in the application of

  13. Efficiency of oxytetracycline treatment in rainbow trout experimentally infected with Flavobacterium psychrophilum strains having different in vitro antibiotic susceptibilities

    DEFF Research Database (Denmark)

    Bruun, Morten Sichlau; Madsen, Lone; Dalsgaard, Inger

    2003-01-01

    The medication effect of oxytetracycline on groups of rainbow trout fry experimentally infected with three strains of Flavobacterium psychrophilum was investigated. The infection model was based on intraperitoneal injection of the pathogen and treatment was done using medicated feed resulting...... in 100 mg oxytetracycline/kg fish for 10 days. The three F. psychrophilum strains had different antimicrobial susceptibilities and successful treatment was only obtained in the trial using a strain with a MICOTC of 0.25 mug/ml. No effect of treatment was seen in the group infected with a strain having...

  14. Effects of Ichthyophonus hoferi on condition indices and blood chemistry of experimentally infected rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Rand, T G; Cone, D K

    1990-07-01

    Body condition, hepatosomatic index and blood chemistry of Oncorhynchus mykiss experimentally infected with a tissue dwelling fish pathogenic fungus, Ichthyophonus hoferi, were monitored over a 6 wk period. This was to determine whether the infection constituted a stress manifest by changes in the hypothalamic-pituitary interrenal axis, and especially plasma cortisol levels. Infection caused anaemia and leucopenia but did not change the condition, hepatosomatic indices, or plasma chloride, cholesterol, cortisol, creatinine, glucose, osmolarity, potassium, total protein, sodium and T4. It is suggested that increased cortisol levels may not be a normal component of the stress response of fish to disease caused by invasive infectious agents.

  15. Molecular assays for determining Mycobacterium leprae viability in tissues of experimentally infected mice.

    Science.gov (United States)

    Davis, Grace L; Ray, Nashone A; Lahiri, Ramanuj; Gillis, Thomas P; Krahenbuhl, James L; Williams, Diana L; Adams, Linda B

    2013-01-01

    The inability of Mycobacterium leprae to grow on axenic media has necessitated specialized techniques in order to determine viability of this organism. The purpose of this study was to develop a simple and sensitive molecular assay for determining M. leprae viability directly from infected tissues. Two M. leprae-specific quantitative reverse transcription PCR (qRT-PCR) assays based on the expression levels of esxA, encoding the ESAT-6 protein, and hsp18, encoding the heat shock 18 kDa protein, were developed and tested using infected footpad (FP) tissues of both immunocompetent and immunocompromised (athymic nu/nu) mice. In addition, the ability of these assays to detect the effects of anti-leprosy drug treatment on M. leprae viability was determined using rifampin and rifapentine, each at 10 mg/kg for 1, 5, or 20 daily doses, in the athymic nu/nu FP model. Molecular enumeration (RLEP PCR) and viability determinations (qRT-PCR) were performed via Taqman methodology on DNA and RNA, respectively, purified from ethanol-fixed FP tissue and compared with conventional enumeration (microscopic counting of acid fast bacilli) and viability assays (radiorespirometry, viability staining) which utilized bacilli freshly harvested from the contralateral FP. Both molecular and conventional assays demonstrated growth and high viability of M. leprae in nu/nu FPs over a 4 month infection period. In contrast, viability was markedly decreased by 8 weeks in immunocompetent mice. Rifapentine significantly reduced bacterial viability after 5 treatments, whereas rifampin required up to 20 treatments for the same efficacy. Neither drug was effective after a single treatment. In addition, host gene expression was monitored with the same RNA preparations. hsp18 and esxA qRT-PCR are sensitive molecular indicators, reliably detecting viability of M. leprae in tissues without the need for bacterial isolation or immediate processing, making these assays applicable for in vivo drug screening and

  16. Experimental infection of Leishmania (L. chagasi in a cell line derived from Lutzomyia longipalpis (Diptera:Psychodidae

    Directory of Open Access Journals (Sweden)

    Felio J Bello

    2005-10-01

    Full Text Available The present work describes the in vitro infection of a cell line Lulo, derived from Lutzomyia longipalpis embryonic tissue, by Leishmania chagasi promastigotes. This infection process is compared with a parallel one developed using the J774 cell line. The L. chagasi MH/CO/84/CI-044B strain was used for experimental infection in two cell lines. The cells were seeded on glass coverslips in 24-well plates to reach a final number of 2 x 10(5 cells/well. Parasites were added to the adhered Lulo and J774 cells in a 10:1 ratio and were incubated at 28 and 37ºC respectively. After 2, 4, 6, 8, and 10 days post-infection, the cells were extensively washed with PBS, fixed with methanol, and stained with Giemsa. The number of internalized parasites was determined by counting at least 400 cultured cells on each coverslip. The results showed continuous interaction between L. chagasi promastigotes with the cell lines. Some ultrastructural characteristics of the amastigote forms were observed using transmission electron microscopy. The highest percentage of infection in Lulo cells was registered on day 6 post-infection (29.6% and on day 4 in the J774 cells (51%. This work shows similarities and differences in the L. chagasi experimental infection process in the two cell lines. However, Lulo cells emerge as a new model to study the life-cycle of this parasite.

  17. Differential Expression of Tomato Spotted Wilt Virus-Derived Viral Small RNAs in Infected Commercial and Experimental Host Plants

    Science.gov (United States)

    Mitter, Neena; Koundal, Vikas; Williams, Sarah; Pappu, Hanu

    2013-01-01

    Background Viral small RNAs (vsiRNAs) in the infected host can be generated from viral double-stranded RNA replicative intermediates, self-complementary regions of the viral genome or from the action of host RNA-dependent RNA polymerases on viral templates. The vsiRNA abundance and profile as well as the endogenous small RNA population can vary between different hosts infected by the same virus influencing viral pathogenicity and host response. There are no reports on the analysis of vsiRNAs of Tomato spotted wilt virus (TSWV), a segmented negative stranded RNA virus in the family Bunyaviridae, with two of its gene segments showing ambisense gene arrangement. The virus causes significant economic losses to numerous field and horticultural crops worldwide. Principal Findings Tomato spotted wilt virus (TSWV)-specific vsiRNAs were characterized by deep sequencing in virus-infected experimental host Nicotiana benthamiana and a commercial, susceptible host tomato. The total small (s) RNA reads in TSWV-infected tomato sample showed relatively equal distribution of 21, 22 and 24 nt, whereas N. benthamiana sample was dominated by 24 nt total sRNAs. The number of vsiRNA reads detected in tomato was many a magnitude (~350:1) higher than those found in N. benthamiana, however the profile of vsiRNAs in terms of relative abundance 21, 22 and 24 nt class size was similar in both the hosts. Maximum vsiRNA reads were obtained for the M RNA segment of TSWV while the largest L RNA segment had the least number of vsiRNAs in both tomato and N. benthamiana. Only the silencing suppressor, NSs, of TSWV recorded higher antisense vsiRNA with respect to the coding frame among all the genes of TSWV. Significance Details of the origin, distribution and abundance of TSWV vsiRNAs could be useful in designing efficient targets for exploiting RNA interference for virus resistance. It also has major implications toward our understanding of the differential processing of vsiRNAs in antiviral

  18. Differential expression of tomato spotted wilt virus-derived viral small RNAs in infected commercial and experimental host plants.

    Directory of Open Access Journals (Sweden)

    Neena Mitter

    Full Text Available BACKGROUND: Viral small RNAs (vsiRNAs in the infected host can be generated from viral double-stranded RNA replicative intermediates, self-complementary regions of the viral genome or from the action of host RNA-dependent RNA polymerases on viral templates. The vsiRNA abundance and profile as well as the endogenous small RNA population can vary between different hosts infected by the same virus influencing viral pathogenicity and host response. There are no reports on the analysis of vsiRNAs of Tomato spotted wilt virus (TSWV, a segmented negative stranded RNA virus in the family Bunyaviridae, with two of its gene segments showing ambisense gene arrangement. The virus causes significant economic losses to numerous field and horticultural crops worldwide. PRINCIPAL FINDINGS: Tomato spotted wilt virus (TSWV-specific vsiRNAs were characterized by deep sequencing in virus-infected experimental host Nicotiana benthamiana and a commercial, susceptible host tomato. The total small (s RNA reads in TSWV-infected tomato sample showed relatively equal distribution of 21, 22 and 24 nt, whereas N. benthamiana sample was dominated by 24 nt total sRNAs. The number of vsiRNA reads detected in tomato was many a magnitude (~350:1 higher than those found in N. benthamiana, however the profile of vsiRNAs in terms of relative abundance 21, 22 and 24 nt class size was similar in both the hosts. Maximum vsiRNA reads were obtained for the M RNA segment of TSWV while the largest L RNA segment had the least number of vsiRNAs in both tomato and N. benthamiana. Only the silencing suppressor, NSs, of TSWV recorded higher antisense vsiRNA with respect to the coding frame among all the genes of TSWV. SIGNIFICANCE: Details of the origin, distribution and abundance of TSWV vsiRNAs could be useful in designing efficient targets for exploiting RNA interference for virus resistance. It also has major implications toward our understanding of the differential processing of vsi

  19. Behavioral and hormonal changes associated with the infective dose in experimental taeniasis in golden hamsters (Mesocricetus auratus).

    Science.gov (United States)

    Domínguez-Roldan, Rosa; Hallal-Calleros, Claudia; Sciutto, Edda; Hernández, Marisela; Aguirre-Flores, Virginio; García-Jiménez, Sara; Báez-Saldaña, Armida; Flores-Pérez, Fernando Iván

    2016-07-01

    It has been reported that behavioral changes relate to infection in different parasitoses. However, the relation between the extent of the behavioral changes and the magnitude of the infection has been scarcely studied. The aim of this study was to evaluate the relationship between different doses of infection and the behavioral changes induced in the experimental Taenia pisiformis taeniasis in golden hamsters. Groups of nine hamsters were infected with three or six T. pisiformis metacestodes. The locomotor activity was quantified daily in an open field test during the 21 days after infection; anxiety test was performed in an elevated plus-maze with a dark/light area at 7, 14 and 21 days post-infection, and serum cortisol levels were determined by radioimmunoassay before infection and at day 22 after infection. The challenge itself induced modifications on behavior and cortisol levels in hamsters, with or without successful infection (taenia development). Animals challenged with three metacestodes induced a decrease in locomotor activity and an increase in anxiety in infected animals. A higher and earlier decrease in locomotor activity and increased anxiety levels were observed in hamsters challenged with six cysticerci, which were accompanied by higher levels of sera cortisol at the end of the experiment. At necropsy, 44-55% of hamster became infected with an efficiency of implantation of 22-26%, challenged with three or six cysticerci respectively. The challenge of hamsters with metacestodes, promote behavioral changes in an extent dependent on the magnitude of the challenge, disregarding the effectiveness of the infection. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Autocrine production of beta-chemokines protects CMV-Specific CD4 T cells from HIV infection.

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    Joseph P Casazza

    2009-10-01

    Full Text Available Induction of a functional subset of HIV-specific CD4+ T cells that is resistant to HIV infection could enhance immune protection and decrease the rate of HIV disease progression. CMV-specific CD4+ T cells, which are less frequently infected than HIV-specific CD4+ T cells, are a model for such an effect. To determine the mechanism of this protection, we compared the functional response of HIV gag-specific and CMV pp65-specific CD4+ T cells in individuals co-infected with CMV and HIV. We found that CMV-specific CD4+ T cells rapidly up-regulated production of MIP-1alpha and MIP-1beta mRNA, resulting in a rapid increase in production of MIP-1alpha and MIP-1beta after cognate antigen stimulation. Production of beta-chemokines was associated with maturational phenotype and was rarely seen in HIV-specific CD4+ T cells. To test whether production of beta-chemokines by CD4+ T cells lowers their susceptibility to HIV infection, we measured cell-associated Gag DNA to assess the in vivo infection history of CMV-specific CD4+ T cells. We found that CMV-specific CD4+ T cells which produced MIP-1beta contained 10 times less Gag DNA than did those which failed to produce MIP-1beta. These data suggest that CD4+ T cells which produce MIP-1alpha and MIP-1beta bind these chemokines in an autocrine fashion which decreases the risk of in vivo HIV infection.

  1. Analysis of intrahepatic HBV-specific cytotoxic T-cells during and after acute HBV infection in humans

    NARCIS (Netherlands)

    Sprengers, Dave; van der Molen, Renate G.; Kusters, Johannes G.; de Man, Robert A.; Niesters, Hubert G. M.; Schalm, Solko W.; Janssen, Harry L. A.

    2006-01-01

    Characteristics of the intrahepatic virus-specific T-cell response in patients with acute hepatitis B virus (HBV) infection have not been studied due to the risk of complications associated with standard liver biopsies. In this study we aimed to characterize the virus-specific CD8 + T-cell response

  2. Immune responses to the Mycobacterium tuberculosis-specific antigen ESAT-6 signal subclinical infection among contacts of tuberculosis patients

    DEFF Research Database (Denmark)

    Doherty, T Mark; Demissie, Abebech; Olobo, Joseph

    2002-01-01

    Diagnosis of latent Mycobacterium tuberculosis infection is considered essential for tuberculosis control but is hampered by the lack of specific reagents. We report that strong recognition of tuberculosis complex-specific antigen ESAT-6 by healthy household contacts of tuberculosis patients...

  3. Immune responses to the Mycobacterium tuberculosis-specific antigen ESAT-6 signal subclinical infection among contacts of tuberculosis patients

    DEFF Research Database (Denmark)

    Doherty, T Mark; Demissie, Abebech; Olobo, Joseph

    2002-01-01

    Diagnosis of latent Mycobacterium tuberculosis infection is considered essential for tuberculosis control but is hampered by the lack of specific reagents. We report that strong recognition of tuberculosis complex-specific antigen ESAT-6 by healthy household contacts of tuberculosis patients...... correlates with the subsequent development of active tuberculosis during a 2-year follow-up period....

  4. Epitope-Specific Tolerance Modes Differentially Specify Susceptibility to Proteolipid Protein-Induced Experimental Autoimmune Encephalomyelitis

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    Lei Wang

    2017-11-01

    Full Text Available Immunization with myelin components can elicit experimental autoimmune encephalomyelitis (EAE. EAE susceptibility varies between mouse strains, depending on the antigen employed. BL/6 mice are largely resistant to EAE induction with proteolipid protein (PLP, probably a reflection of antigen-specific tolerance. However, the extent and mechanism(s of tolerance to PLP remain unclear. Here, we identified three PLP epitopes in PLP-deficient BL/6 mice. PLP-sufficient mice did not respond against two of these, whereas tolerance was “leaky” for an epitope with weak predicted MHCII binding, and only this epitope was encephalitogenic. In TCR transgenic mice, the “EAE-susceptibility-associated” epitope was “ignored” by specific CD4 T cells, whereas the “resistance-associated” epitope induced clonal deletion and Treg induction in the thymus. Central tolerance was autoimmune regulator dependent and required expression and presentation of PLP by thymic epithelial cells (TECs. TEC-specific ablation of PLP revealed that peripheral tolerance, mediated by dendritic cells through recessive tolerance mechanisms (deletion and anergy, could largely compensate for a lack of central tolerance. However, adoptive EAE was exacerbated in mice lacking PLP in TECs, pointing toward a non-redundant role of the thymus in dominant tolerance to PLP. Our findings reveal multiple layers of tolerance to a central nervous system autoantigen that vary among epitopes and thereby specify disease susceptibility. Understanding how different modalities of tolerance apply to distinct T cell epitopes of a target in autoimmunity has implications for antigen-specific strategies to therapeutically interfere with unwanted immune reactions against self.

  5. A shorter and more specific oral sensitization-based experimental model of food allergy in mice.

    Science.gov (United States)

    Bailón, Elvira; Cueto-Sola, Margarita; Utrilla, Pilar; Rodríguez-Ruiz, Judith; Garrido-Mesa, Natividad; Zarzuelo, Antonio; Xaus, Jordi; Gálvez, Julio; Comalada, Mònica

    2012-07-31

    Cow's milk protein allergy (CMPA) is one of the most prevalent human food-borne allergies, particularly in children. Experimental animal models have become critical tools with which to perform research on new therapeutic approaches and on the molecular mechanisms involved. However, oral food allergen sensitization in mice requires several weeks and is usually associated with unspecific immune responses. To overcome these inconveniences, we have developed a new food allergy model that takes only two weeks while retaining the main characters of allergic response to food antigens. The new model is characterized by oral sensitization of weaned Balb/c mice with 5 doses of purified cow's milk protein (CMP) plus cholera toxin (CT) for only two weeks and posterior challenge with an intraperitoneal administration of the allergen at the end of the sensitization period. In parallel, we studied a conventional protocol that lasts for seven weeks, and also the non-specific effects exerted by CT in both protocols. The shorter protocol achieves a similar clinical score as the original food allergy model without macroscopically affecting gut morphology or physiology. Moreover, the shorter protocol caused an increased IL-4 production and a more selective antigen-specific IgG1 response. Finally, the extended CT administration during the sensitization period of the conventional protocol is responsible for the exacerbated immune response observed in that model. Therefore, the new model presented here allows a reduction not only in experimental time but also in the number of animals required per experiment while maintaining the features of conventional allergy models. We propose that the new protocol reported will contribute to advancing allergy research. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Pathogenesis of Riemerella anatipestifer in turkeys after experimental mono-infection via respiratory routes or dual infection together with the avian metapneumovirus.

    Science.gov (United States)

    Rubbenstroth, Dennis; Ryll, Martin; Behr, Klaus-Peter; Rautenschlein, Silke

    2009-12-01

    Riemerella anatipestifer (RA) is the causative agent of septicaemic and exudative diseases in a variety of bird species. Despite numerous outbreaks, little is known about the pathogenicity of RA for turkeys. We investigated the development of RA-induced disease in commercial turkey poults following RA inoculation via different respiratory routes. Inoculation by aerosol or injection into the abdominal air sac led to systemic infection and mild gross lesions, including pericarditis, epicarditis and airsacculitis, which were less pronounced compared with field outbreaks. It was speculated, that viral pathogens, such as the avian metapneumovirus (aMPV), may exacerbate RA pathogenesis under field conditions. We inoculated turkey poults with virulent aMPV. Subsequently, aMPV-infected and virus-free birds were exposed 3 to 5 days later to a high dose of RA by aerosol (>10(10) colony-forming units/ml in 8 ml aerosol per 11 or 12 birds) or were inoculated 4 days later with a low RA dose (10(4.9) colony-forming units per bird) via the intranasal route. Intranasal RA inoculation with the low bacterial dose led to a respiratory and systemic RA infection in aMPV-infected birds, while virus-free birds remained RA-negative. Following exposure to a high RA dose by aerosol, aMPV-infected groups showed slightly enhanced incidences of gross lesions and RA re-isolation. The present study clearly confirms that RA is pathogenic for turkeys after experimental inoculation via respiratory routes, which are speculated to be the natural route of infection. However, experimental models in this study did not reproduce the severity of RA-related disease as observed under field conditions, which emphasizes the importance of other contributing factors. aMPV-induced respiratory lesions may serve as a predisposing factor for the establishment of RA infection, since they favour colonization of the bacterium.

  7. Gastrointestinal trichostrongylosis can predispose ewes to clinical mastitis after experimental mammary infection.

    Science.gov (United States)

    Mavrogianni, V S; Papadopoulos, E; Gougoulis, D A; Gallidis, E; Ptochos, S; Fragkou, I A; Orfanou, D C; Fthenakis, G C

    2017-10-15

    Objective was to study, in an experimental model, the possible role of gastrointestinal nematode infection in predisposing ewes to mastitis during the lactation period. Twenty-four ewes (A or B [n=12]), free from nematode and trematode helminths, were used. Group A animals received 5000 third-stage larvae of a trichostrongylid helminth cocktail and group B ewes were unparasitised controls. Animals in group A developed gastrointestinal trichostrongylosis confirmed by >500epg in faecal samples; mean epg of group B ewes were Ewes were challenged by deposition of Mannheimia haemolytica into the teat duct. In group A, 7 ewes developed clinical and 5 subclinical mastitis; no ewe in group B developed clinical mastitis, but only subclinical (12 ewes) (P=0.002). M. haemolytica was isolated from 132/132 and 121/132 udder samples from group A or B, respectively (Pewes that developed clinical mastitis than in others which did not (0.709 and 0.162 versus 0.662 and 0.136, respectively; Pewes with subclinical mastitis (in group A or B), inducible-lymphoid-follicles were observed in the teat, which were not observed in ewes with clinical disease. Total pathology scores summed over all days were 127 and 73 for group A or B ewes, respectively (maximum possible 192; Pewes that developed clinical mastitis. It is concluded that, in view of bacterial challenge, gastrointestinal trichostrongylosis and particularly Teladorsagia infection, might lead to clinical mastitis, through various pathogenetic pathways. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Development of Strongylus vulgaris-specific serum antibodies in naturally infected foals.

    Science.gov (United States)

    Nielsen, M K; Vidyashankar, A N; Gravatte, H S; Bellaw, J; Lyons, E T; Andersen, U V

    2014-03-01

    Strongylus vulgaris is regarded as the most pathogenic helminth parasite infecting horses. Migrating larvae cause pronounced endarteritis and thrombosis in the cranial mesenteric artery and adjacent branches, and thromboembolism can lead to ischemia and infarction of large intestinal segments. A recently developed serum ELISA allows detection of S. vulgaris-specific antibodies during the six-month-long prepatent period. A population of horses has been maintained at the University of Kentucky without anthelmintic intervention since 1979, and S. vulgaris has been documented to be highly prevalent. In 2012, 12 foals were born in this population, and were studied during a 12-month period (March-March). Weekly serum samples were collected to monitor S. vulgaris specific antibodies with the ELISA. Nine colts underwent necropsy at different time points between 90 and 300 days of age. At necropsy, Strongylus spp. and Parascaris equorum were identified to species and stage and enumerated. Initial statistical findings indicate a significant interaction between foal age and ELISA results (pvulgaris-directed maternal antibodies transferred in the colostrum, but then remained ELISA negative during their first three months of life. Foals born in February and March became ELISA positive at about 12 weeks of age, while those born in April and May went positive at about 15 and 21 weeks, respectively. Foal date of birth was significantly associated with ELISA results (pvulgaris burdens (pvulgaris, S. edentatus, and P. equorum burdens (pvulgaris larvae leaving the bloodstream and migrating back to the intestine. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Cause-specific excess mortality in siblings of patients co-infected with HIV and hepatitis C virus

    DEFF Research Database (Denmark)

    Hansen, Ann-Brit Eg; Lohse, Nicolai; Gerstoft, Jan

    2007-01-01

    BACKGROUND: Co-infection with hepatitis C in HIV-infected individuals is associated with 3- to 4-fold higher mortality among these patients' siblings, compared with siblings of mono-infected HIV-patients or population controls. This indicates that risk factors shared by family members partially...... account for the excess mortality of HIV/HCV-co-infected patients. We aimed to explore the causes of death contributing to the excess sibling mortality. METHODOLOGY AND PRINCIPAL FINDINGS: We retrieved causes of death from the Danish National Registry of Deaths and estimated cause-specific excess mortality......-years, compared with siblings of matched population controls. Substance abuse-related deaths contributed most to the elevated mortality among siblings [EMR = 2.25 (1.09-3.40)] followed by unnatural deaths [EMR = 0.67 (-0.05-1.39)]. No siblings of HIV/HCV co-infected patients had a liver-related diagnosis...

  10. Effects of Non-Susceptible Hosts on the Infection with Trypanosoma cruzi of the Vector Triatoma infestans: an Experimental Model

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    Vázquez Diego P

    1999-01-01

    Full Text Available We tested experimentally the effects of the presence of non-susceptible hosts on the infection with Trypanosoma cruzi of the vector Triatoma infestans. The experiment consisted in two treatments: with chickens, including two chickens (non-susceptible hosts and two infected guinea pigs (susceptible hosts, and without chickens, including only two infected guinea pigs. The hosts were held unrestrained in individual metal cages inside a closed tulle chamber. A total of 200 uninfected T. infestans third instar nymphs were liberated in each replica, collected on day 14, and examined for infection and blood meal sources on day 32-36. The additional presence of chickens relative to infected guinea pigs: (a significantly modified the spatial distribution of bugs; (b increased significantly the likelihoods of having a detectable blood meal on any host and molting to the next instar; (c did not affect the bugs' probability of death by predation; and (d decreased significantly the overall percentage of T. infestans infected with T. cruzi. The bugs collected from inside or close to the guinea pigs' cages showed a higher infection rate (71-88% than those collected from the chickens' cages (22-32%. Mixed blood meals on chickens and guinea pigs were detected in 12-21% of bugs. Although the presence of chickens would decrease the overall percentage of infected bugs in short term experiments, the high rate of host change of T. infestans would make this difference fade out if longer exposure times had been provided.

  11. Experimental infection of broiler chicks with Salmonella Typhimurium from pigeon (Columba livia

    Directory of Open Access Journals (Sweden)

    Átilla Holanda de Albuquerque

    2016-08-01

    Full Text Available Several cases of animal and human salmonellosis caused by the Salmonella serotype Typhimurium have been reported. In animals, subclinical infection favors pathogen dissemination through feces. In this context, the domestic pigeon (Columba livia with an asymptomatic condition may play an important role in the transmission of salmonellosis, through the elimination of contaminated feces in commercial aviaries or in poultry feed facilities, causing economic losses to the poultry industry and presenting a risk to public health. This study aimed to evaluate the mortality, clinical signs and the presence of Salmonella Typhimurium in the feces and organs of chicks previously inoculated with bacteria isolated from a pigeon. One-day-old chicks were distributed in two experimental groups (G1 and G2 of 32 birds each, and a control group of six birds. Two inocula of 0.4 and 0.7 mL with 105 and 106 colony forming units were used in G1 and G2 birds, respectively. At 1, 4, 7 and 14 days post-inoculation (dpi fecal samples were pooled from each cage and individual cloacal swabs were collected. At 14 dpi, all chicks were euthanized and samples were collected from the liver, spleen, lung, cecum and intestine for microbiological analysis. Mortality was only observed among G2 birds (6.25%. Most birds presented clinical signs of diarrhea at 4 dpi and no symptom as observed at 14 dpi. The results from cloacal swabs demonstrated bacterial elimination in 68.8% and 53.1% of G2 and G1 birds, respectively at 1 dpi. Additionally, fecal samples had elevated bacterial shedding in all four periods of observation , with a higher excretion at 4 dpi (62.5% for both groups. Among G2 birds, 74.2% were positive for the pathogen in the intestine; G1 birds presented the lowest rate of lung infection (29%, and both groups had more than 50% positivity for liver and caeca. The results revealed that infected chicks with a Salmonella Typhimurium strains isolated from pigeons may host the

  12. Virus-specific immune memory at peripheral sites of herpes simplex virus type 2 (HSV-2 infection in guinea pigs.

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    Jingya Xia

    Full Text Available Despite its importance in modulating HSV-2 pathogenesis, the nature of tissue-resident immune memory to HSV-2 is not completely understood. We used genital HSV-2 infection of guinea pigs to assess the type and location of HSV-specific memory cells at peripheral sites of HSV-2 infection. HSV-specific antibody-secreting cells were readily detected in the spleen, bone marrow, vagina/cervix, lumbosacral sensory ganglia, and spinal cord of previously-infected animals. Memory B cells were detected primarily in the spleen and to a lesser extent in bone marrow but not in the genital tract or neural tissues suggesting that the HSV-specific antibody-secreting cells present at peripheral sites of HSV-2 infection represented persisting populations of plasma cells. The antibody produced by these cells isolated from neural tissues of infected animals was functionally relevant and included antibodies specific for HSV-2 glycoproteins and HSV-2 neutralizing antibodies. A vigorous IFN-γ-secreting T cell response developed in the spleen as well as the sites of HSV-2 infection in the genital tract, lumbosacral ganglia and spinal cord following acute HSV-2 infection. Additionally, populations of HSV-specific tissue-resident memory T cells were maintained at these sites and were readily detected up to 150 days post HSV-2 infection. Unlike the persisting plasma cells, HSV-specific memory T cells were also detected in uterine tissue and cervicothoracic region of the spinal cord and at low levels in the cervicothoracic ganglia. Both HSV-specific CD4+ and CD8+ resident memory cell subsets were maintained long-term in the genital tract and sensory ganglia/spinal cord following HSV-2 infection. Together these data demonstrate the long-term maintenance of both humoral and cellular arms of the adaptive immune response at the sites of HSV-2 latency and virus shedding and highlight the utility of the guinea pig infection model to investigate tissue-resident memory in the

  13. Virus-specific immune memory at peripheral sites of herpes simplex virus type 2 (HSV-2) infection in guinea pigs.

    Science.gov (United States)

    Xia, Jingya; Veselenak, Ronald L; Gorder, Summer R; Bourne, Nigel; Milligan, Gregg N

    2014-01-01

    Despite its importance in modulating HSV-2 pathogenesis, the nature of tissue-resident immune memory to HSV-2 is not completely understood. We used genital HSV-2 infection of guinea pigs to assess the type and location of HSV-specific memory cells at peripheral sites of HSV-2 infection. HSV-specific antibody-secreting cells were readily detected in the spleen, bone marrow, vagina/cervix, lumbosacral sensory ganglia, and spinal cord of previously-infected animals. Memory B cells were detected primarily in the spleen and to a lesser extent in bone marrow but not in the genital tract or neural tissues suggesting that the HSV-specific antibody-secreting cells present at peripheral sites of HSV-2 infection represented persisting populations of plasma cells. The antibody produced by these cells isolated from neural tissues of infected animals was functionally relevant and included antibodies specific for HSV-2 glycoproteins and HSV-2 neutralizing antibodies. A vigorous IFN-γ-secreting T cell response developed in the spleen as well as the sites of HSV-2 infection in the genital tract, lumbosacral ganglia and spinal cord following acute HSV-2 infection. Additionally, populations of HSV-specific tissue-resident memory T cells were maintained at these sites and were readily detected up to 150 days post HSV-2 infection. Unlike the persisting plasma cells, HSV-specific memory T cells were also detected in uterine tissue and cervicothoracic region of the spinal cord and at low levels in the cervicothoracic ganglia. Both HSV-specific CD4+ and CD8+ resident memory cell subsets were maintained long-term in the genital tract and sensory ganglia/spinal cord following HSV-2 infection. Together these data demonstrate the long-term maintenance of both humoral and cellular arms of the adaptive immune response at the sites of HSV-2 latency and virus shedding and highlight the utility of the guinea pig infection model to investigate tissue-resident memory in the setting of HSV-2 latency

  14. 99mTc-UBI Biokinetics: A Specific Peptide for Infection Detection

    Science.gov (United States)

    Rodríguez-Cortés, J.; Meléndez-Alafort, L.; Herrera-Rodríguez, R.; Ferro-Flores, G.; Mitsoura, E.; Martínez-Duncker, C.

    2003-09-01

    Recently, antimicrobial peptides have been proposed as new agents to distinguish between bacterial infections and sterile inflammatory processes. Based on these considerations, Ubiquicidin peptide 29-41 (UBI) has been labeled with 99mTc using a new direct method showing a radiochemical purity > 97 %, high stability in human serum, and low protein binding. In addition 99mTc-UBI showed a specific in vitro and in vivo binding to bacteria. However its biokinetic parameters have not been evaluated since it is one of the new generation radiopharmaceuticals based on peptide structures. Therefore the aim of this project was to establish the biokinetic model for 99mTc-UBI. An activity from 74 to 148 MBq was injected to patients with bone infection and 5 whole body scans were taken at 1, 30, 120, 240 min and 24 h after radiopharmaceutical administration, with a dual head scanner. Urine was collected for 24 h. An antropomorphic phantom was previously used to calculate the effect of attenuation and scattered radiation on the gamma camera acquisition images. ROIs of the selected organs in patients (kidney, liver, heart, bone, soft tissue and lesion) were drawn, and attenuation and scatter corrected. The % urine elimination at 24 h and time integrated ROIs (cpm/pixel/ROIs) were used to obtain the residence time (τ) in each tissue and to establish the biokinetic model. Pharmacokinetic data show that blood clearance is biexponential with a mean residence time in the central compartment of 0.52 h. The images showed non-accumulation in metabolic organs. More than 75 % of the injected activity was eliminated by renal clearance 4 h after 99mTc-UBI administration. The mean radiation dose calculated according to the MIRD formalism was 0.130 mGy/MBq for kidney and the effective dose was 4.29 × 10-3 mSv/MBq.

  15. Characterization and specificity of probiotics to prevent salmonella infection in mice

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    Ana Andino

    2014-08-01

    Full Text Available Background: Probiotic strains of bacteria can prevent Salmonella from causing disease by preventing the pathogen from colonizing the intestines. Two strains of probiotics, Lactobacillus acidophilius and Pediococcus spp, that were obtained from poultry fecal samples have been shown to be efficacious in poultry. The objective of this study was to determine if these strains of probiotics could prevent salmonellosis in a mouse model. Methods: First, both strains of probiotics were evaluated for in vitro efficacy to inhibit the growth of and interfere with virulence gene regulation in Salmonella enterica. For in vivo efficacy, mice was used which models Typhoid illness. Mice were divided into 2 groups: Control and treatment, Lactobacillus and Pediococcus (LP; 108 Log CFU. Two experiments were conducted. In the first experiment, the mice were treated with LP in water for the first two days of the experiment and challenged with Salmonella at day three. In the second experiment, the LP treatment was given in the water for 10 days and challenge was performed on day 11. In both experiments, at day 20 post-challenge, all mice were sacrificed, intestinal tracts and organs removed and cultured for Salmonella. Results: The probiotic strains inhibited the growth of Salmonella and down-regulation of virulence genes was noted, but dependent on the strain of Salmonella being evaluated. For the in vivo experiment, the probiotics did not afford the mice protection from infection and increasing the length of time the probiotics were administered did not improve the efficacy of the probiotics. Conclusions: It appears that these strains of probiotic bacteria are effective against Salmonella in vitro. However, these isolates did not afford protection from Salmonella infection to mice which may be due to host specifity as these isolates were obtained from poultry

  16. Nonorgan-specific autoantibodies in HIV-infected patients in the HAART era.

    Science.gov (United States)

    Iordache, Laura; Bengoufa, Djaouida; Taulera, Olivier; Rami, Agathe; Lascoux-Combe, Caroline; Day, Nesrine; Parrinello, Maguy; Sellier, Pierre-Olivier; Molina, Jean-Michel; Mahr, Alfred

    2017-03-01

    Nonorgan-specific autoantibodies (AAbs) are used for diagnosing autoimmune diseases but can also be detected in other conditions. We carried out a cross-sectional study with the aim to screen HIV1-infected patients in the era of highly active antiretroviral therapy (HAART) for AAbs and to analyze the association of their presence with hypergammaglobulinemia and immunovirological status.Blood samples from HIV1-infected patients without major concomitant illnesses followed in 2 hospitals in Paris, France were tested for immunovirological status, serum immunoglobulin G (IgG) level, antinuclear antibodies (ANAs), anti-double-stranded DNA (anti-dsDNA), anti-extractable nuclear antigens (anti-ENAs), anticardiolipin (aCL), anti-β2glycoprotein1 (anti-β2GP1), and antineutrophil cytoplasmic antibodies (ANCAs). Clinically relevant AAbs were defined as ANAs with titers ≥1:160, anti-dsDNA or anti-ENA antibodies; aCL or anti-β2GP1 antibodies with a level ≥40 U/ml; and ANCAs reacting with proteinase 3 or myeloperoxidase.We included 92 patients (mean age 47 years, men 55%, sub-Saharan African background 55%, HAART 85%, mean CD4 lymphocyte count 611/mm, viral load < 40 copies/mL 74%). At least 1 AAb was detected in 45% of patients, mostly ANAs (33%) and ANCAs (13%); 12% had ≥1 clinically relevant AAb. Above-normal IgG levels were found in 71% of patients. We found an inverse association between the presence of ≥1 AAb and CD4 lymphocyte count (P = 0.03) and between above-normal IgG levels and duration of virological control (P = 0.02) and non-sub-Saharan African background (P = 0.001).In sum, in HIV1-infected patients without any major concomitant illness in the HAART era, the prevalence of AAbs remains high but AAb patterns leading to high suspicion of autoimmune diseases are rather uncommon. AAb presence is associated with reduced CD4 lymphocyte count but not hypergammaglobulinemia.

  17. Non-oncogenic Acute Viral Infections Disrupt Anti-cancer Responses and Lead to Accelerated Cancer-Specific Host Death

    Directory of Open Access Journals (Sweden)

    Frederick J. Kohlhapp

    2016-10-01

    Full Text Available In light of increased cancer prevalence and cancer-specific deaths in patients with infections, we investigated whether infections alter anti-tumor immune responses. We report that acute influenza infection of the lung promotes distal melanoma growth in the dermis and leads to accelerated cancer-specific host death. Furthermore, we show that during influenza infection, anti-melanoma CD8+ T cells are shunted from the tumor to the infection site, where they express high levels of the inhibitory receptor programmed cell death protein 1 (PD-1. Immunotherapy to block PD-1 reverses this loss of anti-tumor CD8+ T cells from the tumor and decreases infection-induced tumor growth. Our findings show that acute non-oncogenic infection can promote cancer growth, raising concerns regarding acute viral illness sequelae. They also suggest an unexpected role for PD-1 blockade in cancer immunotherapy and provide insight into the immune response when faced with concomitant challenges.

  18. An investigation on vertical transmission of Leishmania infantum in experimentally infected dogs and assessment of offspring's infectiousness potential by xenodiagnosis.

    Science.gov (United States)

    Ben Slimane, T; Chouihi, E; Ben Hadj Ahmed, S; Chelbi, I; Barhoumi, W; Cherni, S; Zoghlami, Z; Gharbi, M; Zhioua, E

    2014-12-15

    Dogs are the main reservoir host of Leishmania infantum, etiologic agent of human visceral leishmaniasis (HVL) and canine visceral leishmaniasis (CVL). Transmission of L. infantum to humans and dogs is mainly through the bite of infected sand flies. In the Western Mediterranean basin, Phlebotomus perniciosus is the main vector of L. infantum. However, occasional vertical transmission of L. infantum has been reported. This study investigated L. infantum vertical transmission in offspring of experimentally infected dogs. Among 14 surviving puppies from three female beagle dogs that developed CVL following an experimental infection with L. infantum, one was tested positive by indirect immunofluorescence antibody test, by PCR and by xenodiagnosis with a high parasite burden in the spleen at 14 months old. None of the remaining puppies were tested positive for L. infantum. These findings strongly suggest that infected puppies following vertical transmission can sustain infection and contribute in infecting sand flies with L. infantum. Any strategy for controlling CVL should take into consideration the vertical transmission of L. infantum. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Clinical presentation, convalescence, and relapse of rocky mountain spotted fever in dogs experimentally infected via tick bite.

    Directory of Open Access Journals (Sweden)

    Michael L Levin

    Full Text Available Rocky Mountain spotted fever (RMSF is a tick-borne disease caused by R. rickettsii in North and South America. Domestic dogs are susceptible to infection and canine RMSF can be fatal without appropriate treatment. Although clinical signs of R. rickettsii infection in dogs have been described, published reports usually include descriptions of either advanced clinical cases or experimental infections caused by needle-inoculation of cultured pathogen rather than by tick bite. The natural progression of a tick-borne R. rickettsii infection has not been studied in sufficient detail. Here, we provide a detailed description of clinical, hematological, molecular, and serological dynamics of RMSF in domestic dogs from the day of experimental exposure to infected ticks through recovery. Presented data indicate that neither the height/duration of fever nor detection of rickettsial DNA in dogs' blood by PCR are good indicators for clinical prognosis. Only the apex and subsequent subsidence of neutrophilia seem to mark the beginning of recovery and allow predicting a favorable outcome in Rickettsia-infected dogs, even despite the continuing persistence of mucosal petechiae and skin rash. On the other hand the appropriate (doxycycline antibiotic therapy of sufficient duration is crucial in prevention of RMSF relapses in dogs.

  20. Clinical presentation, convalescence, and relapse of rocky mountain spotted fever in dogs experimentally infected via tick bite.

    Science.gov (United States)

    Levin, Michael L; Killmaster, Lindsay F; Zemtsova, Galina E; Ritter, Jana M; Langham, Gregory

    2014-01-01

    Rocky Mountain spotted fever (RMSF) is a tick-borne disease caused by R. rickettsii in North and South America. Domestic dogs are susceptible to infection and canine RMSF can be fatal without appropriate treatment. Although clinical signs of R. rickettsii infection in dogs have been described, published reports usually include descriptions of either advanced clinical cases or experimental infections caused by needle-inoculation of cultured pathogen rather than by tick bite. The natural progression of a tick-borne R. rickettsii infection has not been studied in sufficient detail. Here, we provide a detailed description of clinical, hematological, molecular, and serological dynamics of RMSF in domestic dogs from the day of experimental exposure to infected ticks through recovery. Presented data indicate that neither the height/duration of fever nor detection of rickettsial DNA in dogs' blood by PCR are good indicators for clinical prognosis. Only the apex and subsequent subsidence of neutrophilia seem to mark the beginning of recovery and allow predicting a favorable outcome in Rickettsia-infected dogs, even despite the continuing persistence of mucosal petechiae and skin rash. On the other hand the appropriate (doxycycline) antibiotic therapy of sufficient duration is crucial in prevention of RMSF relapses in dogs.

  1. Polyfunctional analysis of Gag and Nef specific CD8+ T-cell responses in HIV-1 infected Indian individuals.

    Science.gov (United States)

    Mendiratta, Sanjay; Vajpayee, Madhu; Mojumdar, Kamalika; Chauhan, Neeraj K; Sreenivas, Vishnubhatla

    2011-02-01

    Polyfunctional CD8+ T-cells have been described as most competent in controlling viral replication. We studied the impact of antigen persistence on the polyfunctional immune responses of CD8+ T-lymphocytes to HIV Gag and Nef peptides and polyclonal stimuli in 40 ART naïve HIV infected individuals and analyzed the alterations in T-cell functionality in early and late stages of infection. Significantly elevated level of global response and polyfunctional profile of CD8+ T-cells were observed to polyclonal stimulation, than HIV specific antigens in chronically infected individuals. However no key differences were observed in CD8+ T-cell functional profile in any of the 15 unique subsets for Gag and Nef specific antigens. The subjects in early stage of infection (defined as a gap of 6 months or less between seroconversion and enrolment and with no apparent clinical symptoms) had a higher degree of response functionality (4+ or 3+ different functions simultaneously) than in the late stage infection (defined as time duration since seroconversion greater than 6 months). The data suggest that persistence of antigen during chronic infection leads to functional impairment of HIV specific responses. Copyright © 2010 Elsevier Ltd. All rights reserved.

  2. Experimental infection of Carrion crows (Corvus corone) with two European West Nile virus (WNV) strains.

    Science.gov (United States)

    Dridi, Maha; Vangeluwe, Didier; Lecollinet, Sylvie; van den Berg, Thierry; Lambrecht, Bénédicte

    2013-07-26

    West Nile virus (WNV) has become a wide-spread arbovirus in Europe and the Mediterranean Basin countries. This emerging zoonotic disease disseminated 13 years ago in North America where its impact on animal and public health has been considerable. Although American corvids have been the most reliable avian sentinels for WN surveillance in the United States, there is so far no data available about the susceptibility of their Western European counterparts to WNV. Clinical follow-up and serum, oral swabs and feathers viral RNA load monitoring was herein performed on wild-caught Carrion crows (Corvus corone) experimentally inoculated with two WNV strains, Is98 that was isolated from a stork in Israel where it elicited high rates of avian deaths in 1998, and Fr2000 which was only associated to sporadic equine cases in Camargue, France in 2000. Inoculated crows were sensitive to both WNV infections and, as expected from the available epidemiological data, Is98 induced a higher mortality rate (100% vs. 33%) and a quicker fatal outcome, with higher viral RNA loads detected in the serum, oral swabs and feathers than in the Fr2000 group. Therefore, Carrion crows should also be a target species for WNV surveillance in Western Europe, where reporting for abnormal mortalities could be completed by viral detection in the herein described avian matrices. These experimental findings also emphasize the peculiarity of the European situation where a large spectrum of WNV genetic and pathotypic variants have been so far isolated despite limited WN disease reports in wild birds. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Lipopolysaccharide-specific memory B cell responses to an attenuated live cholera vaccine are associated with protection against Vibrio cholerae infection.

    Science.gov (United States)

    Haney, Douglas J; Lock, Michael D; Gurwith, Marc; Simon, Jakub K; Ishioka, Glenn; Cohen, Mitchell B; Kirkpatrick, Beth D; Lyon, Caroline E; Chen, Wilbur H; Sztein, Marcelo B; Levine, Myron M; Harris, Jason B

    2018-05-11

    The single-dose live attenuated vaccine CVD 103-HgR protects against experimental Vibrio cholerae infection in cholera-naïve adults for at least 6 months after vaccination. While vaccine-induced vibriocidal seroconversion is associated with protection, vibriocidal titers decline rapidly from their peak 1-2 weeks after vaccination. Although vaccine-induced memory B cells (MBCs) might mediate sustained protection in individuals without detectable circulating antibodies, it is unknown whether oral cholera vaccination induces a MBC response. In a study that enrolled North American adults, we measured lipopolysaccharide (LPS)- and cholera toxin (CtxB)-specific MBC responses to PXVX0200 (derived from the CVD 103-HgR strain) and assessed stool volumes following experimental Vibrio cholerae infection. We then evaluated the association between vaccine-induced MBC responses and protection against cholera. There was a significant increase in % CT-specific IgG, % LPS-specific IgG, and % LPS-specific IgA MBCs which persisted 180 days after vaccination as well as a significant association between vaccine-induced increase in % LPS-specific IgA MBCs and lower post-challenge stool volume (r = -0.56, p < 0.001). Oral cholera vaccination induces antigen-specific MBC responses, and the anamnestic LPS-specific responses may contribute to long-term protection and provide correlates of the duration of vaccine-induced protection. NCT01895855. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  4. Nanoparticle-mediated drug delivery to treat infections in the female reproductive tract: evaluation of experimental systems and the potential for mathematical modeling.

    Science.gov (United States)

    Sims, Lee B; Frieboes, Hermann B; Steinbach-Rankins, Jill M

    2018-01-01

    A variety of drug-delivery platforms have been employed to deliver therapeutic agents across cervicovaginal mucus (CVM) and the vaginal mucosa, offering the capability to increase the longevity and retention of active agents to treat infections of the female reproductive tract (FRT). Nanoparticles (NPs) have been shown to improve retention, diffusion, and cell-specific targeting via specific surface modifications, relative to other delivery platforms. In particular, polymeric NPs represent a promising option that has shown improved distribution through the CVM. These NPs are typically fabricated from nontoxic, non-inflammatory, US Food and Drug Administration-approved polymers that improve biocompatibility. This review summarizes recent experimental studies that have evaluated NP transport in the FRT, and highlights research areas that more thoroughly and efficiently inform polymeric NP design, including mathematical modeling. An overview of the in vitro, ex vivo, and in vivo NP studies conducted to date - whereby transport parameters are determined, extrapolated, and validated - is presented first. The impact of different NP design features on transport through the FRT is summarized, and gaps that exist due to the limitations of iterative experimentation alone are identified. The potential of mathematical modeling to complement the characterization and evaluation of diffusion and transport of delivery vehicles and active agents through the CVM and mucosa is discussed. Lastly, potential advancements combining experimental and mathematical knowledge are suggested to inform next-generation NP designs, such that infections in the FRT may be more effectively treated.

  5. The sensitivity and the specifity of rapid antigen test in streptococcal upper respiratory tract infections.

    Science.gov (United States)

    Gurol, Yesim; Akan, Hulya; Izbirak, Guldal; Tekkanat, Zuhal Tazegun; Gunduz, Tehlile Silem; Hayran, Osman; Yilmaz, Gulden

    2010-06-01

    It is aimed to detect the sensitivity and specificity of rapid antigen detection of group A beta hemolytic streptococci from throat specimen compared with throat culture. The other goal of the study is to help in giving clinical decisions in upper respiratory tract infections according to the age group, by detection of sensitivity and positive predictive values of the rapid tests and throat cultures. Rapid antigen detection and throat culture results for group A beta hemolytic streptococci from outpatients attending to our university hospital between the first of November 2005 and 31st of December 2008 were evaluated retrospectively. Throat samples were obtained by swabs from the throat and transported in the Stuart medium and Quickvue Strep A [Quidel, San Diego, USA] cassette test was applied and for culture, specimen was inoculated on 5% blood sheep agar and identified according to bacitracin and trimethoprim-sulphametaxazole susceptibility from beta hemolytic colonies. During the dates between the first of November 2005 and 31st of December 2008, from 453 patients both rapid antigen detection and throat culture were evaluated. Rapid antigen detection sensitivity and specificity were found to be 64.6% and 96.79%, respectively. The positive predictive value was 80.95% whereas negative predictive value was 92.82%. Kappa index was 0.91. When the results were evaluated according to the age groups, the sensitivity and the positive predictive value of rapid antigen detection in children were 70%, 90.3% and in adults 59.4%, 70.4%. When bacterial infection is concerned to prevent unnecessary antibiotic use, rapid streptococcal antigen test (RSAT) is a reliable method to begin immediate treatment. To get the maximum sensitivity of RSAT, the specimen collection technique used and education of the health care workers is important. While giving clinical decision, it must be taken into consideration that the sensitivity and the positive predictive value of the RSAT is quite

  6. Lack of prion transmission by sexual or parental routes in experimentally infected hamsters.

    Science.gov (United States)

    Morales, Rodrigo; Pritzkow, Sandra; Hu, Ping Ping; Duran-Aniotz, Claudia; Soto, Claudio

    2013-01-01

    Prion diseases are a group of neurodegenerative disorders affecting humans as well as captive and wild animals. The mechanisms and routes governing the natural spread of prions are not completely understood and several hypotheses have been proposed. In this study, we analyzed the effect of gender in prion incubation period, as well as the possibility of prion transmission by sexual and parental contact using 263K infected hamsters as a model. Our results show that males have significantly longer incubation periods compared with females when exposed to the same quantity of infectious material. Importantly, no evidence of sexual or parental prion transmission was found, even 500 d after sexual contact or birth, respectively. Western blotting and PMCA were unable to detect sub-clinical levels of PrP(Sc) in experimental subjects, suggesting a complete absence of prion transmission by these routes. Our results show that sexual and parental transmission of prions does not occur in this model. It remains to be studied whether this conclusion is valid also for other prion strains and species.

  7. Preclinical deposition of pathological prion protein in muscle of experimentally infected primates.

    Directory of Open Access Journals (Sweden)

    Susanne Krasemann

    Full Text Available Prion diseases are transmissible fatal neurodegenerative disorders affecting humans and animals. A central step in disease progression is the accumulation of a misfolded form (PrP(Sc of the host encoded prion protein (PrP(C in neuronal and non-neuronal tissues. The involvement of peripheral tissues in preclinical states increases the risk of accidental transmission. On the other hand, detection of PrP(Sc in non-neuronal easy-accessible compartments such as muscle may offer a novel diagnostic tool. Primate models have proven invaluable to investigate prion diseases. We have studied the deposition of PrP(Sc in muscle and central nervous system of rhesus monkeys challenged with sporadic Creutzfeldt-Jakob disease (sCJD, variant CJD (vCJD and bovine spongiform encephalopathy (BSE in preclinical and clinical stage using biochemical and morphological methods. Here, we show the preclinical presence of PrP(Sc in muscle and central nervous system of rhesus monkeys experimentally infected with vCJD.

  8. Experimental single and trickle infections of cattle with Taenia saginata: Studies of immunodiagnosis

    DEFF Research Database (Denmark)

    Bøgh, H.O.; Grønvold, J.; Maeda, G.E.

    1996-01-01

    Two groups of 12 calves were given either a single infection dose of 30,000 Taenia saginata eggs (group A) or trickle infected with 12 x 2500 T saginata eggs (group B). The calves were killed 16, 22 or 54 weeks after infection and the numbers of viable and dead parasites were counted by slicing...

  9. Immune gene expression in the spleen of chickens experimentally infected with Ascaridia galli

    DEFF Research Database (Denmark)

    Dalgaard, Tina S.; Skovgaard, Kerstin; Norup, Liselotte R.

    2015-01-01

    Ascaridia galli is a gastrointestinal nematode infecting chickens. Chickens kept in alternative rearing systems or at free-range experience increased risk for infection with resulting high prevalences. A. gall infection causes reduced weight gain, decreased egg production and in severe cases incr...

  10. Experimental infection of pregnant goats with bovine viral diarrhea virus (BVDV)1 or 2

    Science.gov (United States)

    Infections with bovine viral diarrhea virus (BVDV) of the genus pestivirus, family Flaviviridae, are not limited to cattle but occur in various artiodactyls. Persistently infected (PI) cattle are the main source of BVDV. Persistent infections also occur in heterologous hosts such as sheep and deer. ...

  11. Impact of the post-weaning parasitism history on an experimental Haemonchus contortus infection in Creole goat kids.

    Science.gov (United States)

    Ceï, W; Mahieu, M; Philibert, L; Arquet, R; Alexandre, G; Mandonnet, N; Bambou, J C

    2015-01-15

    Gastrointestinal nematode (GIN) infections have an important negative impact on small ruminant production. The selection of genotypes resistant to these parasitic infections is a promising alternative control strategy. Thus, resistance against GIN is an important component of small ruminant breeding schemes, based on phenotypic measurements of resistance in immune mature infected animals. In this study we evaluated both the impact of the post-weaning parasitism history on the response to an experimental Haemonchus contortus infection of resistant and susceptible Creole kids chosen on the basis of their estimated breeding value, and the interaction with the kid's genetic status. During the post-weaning period (from 3 months until 7 months of age) Creole kids were reared at pasture according to four different levels of a mixed rotational stocking system with Creole cattle: 100% (control), 75% (GG75), 50% (GG50), and 25% (GG25) of the total stocking rate of the pasture. The level of infection of the kids decreased significantly at 50% and 25% of the total stocking rate. After the post-weaning period at pasture, at 11 months of age kids were experimentally infected with H. contortus. The faecal egg counts (FEC) were significantly lower in the groups showing the highest FEC at pasture. This result suggests that a degree of protection against an experimental H. contortus infection occurred during the post-weaning period and was dependant on the level of parasitism. Interestingly, no interaction was observed between this level of protection and the genetic status. In conclusion, the level of post-weaning natural parasitism history at pasture would not influence the genetic status evaluation. More generally our results suggest that it would be better to expose kids to a high level of gastrointestinal parasitism during the post-weaning period in order to increase the basal level of resistance thereafter. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Vaccination with experimental feline immunodeficiency virus vaccines, based on autologous infected cells, elicits enhancement of homologous challenge infection

    NARCIS (Netherlands)

    J.A. Karlas (Jos); C.H.J. Siebelink (Kees); M.A. Peer; W. Huisman (Willem); A.M. Cuisinier; G.F. Rimmelzwaan (Guus); A.D.M.E. Osterhaus (Albert)

    1999-01-01

    textabstractCats were vaccinated with fixed autologous feline immunodeficiency virus (FIV)-infected cells in order to present viral proteins to the immune system of individual cats in an MHC-matched fashion. Upon vaccination, a humoral response against Gag was induced. Furthermore,

  13. Novel experimental Pseudomonas aeruginosa lung infection model mimicking long-term host-pathogen interactions in cystic fibrosis

    DEFF Research Database (Denmark)

    Moser, Claus; van Gennip, Maria; Bjarnsholt, Thomas

    2009-01-01

    Moser C, van Gennip M, Bjarnsholt T, Jensen PO, Lee B, Hougen HP, Calum H, Ciofu O, Givskov M, Molin S, Hoiby N. Novel experimental Pseudomonas aeruginosa lung infection model mimicking long-term host-pathogen interactions in cystic fibrosis. APMIS 2009; 117: 95-107. The dominant cause of premature...... death in patients suffering from cystic fibrosis (CF) is chronic lung infection with Pseudomonas aeruginosa. The chronic lung infection often lasts for decades with just one clone. However, as a result of inflammation, antibiotic treatment and different niches in the lungs, the clone undergoes...... and 2003) of the chronic lung infection of one CF patient using the seaweed alginate embedment model. The results showed that the non-mucoid clones reduced their virulence over time, resulting in faster clearing of the bacteria from the lungs, improved pathology and reduced pulmonary production...

  14. Experimental infection of macaques with a wild water bird-derived highly pathogenic avian influenza virus (H5N1.

    Directory of Open Access Journals (Sweden)

    Tomoko Fujiyuki

    Full Text Available Highly pathogenic avian influenza virus (HPAIV continues to threaten human health. Non-human primate infection models of human influenza are desired. To establish an animal infection model with more natural transmission and to determine the pathogenicity of HPAIV isolated from a wild water bird in primates, we administered a Japanese isolate of HPAIV (A/whooper swan/Hokkaido/1/2008, H5N1 clade 2.3.2.1 to rhesus and cynomolgus monkeys, in droplet form, via the intratracheal route. Infection of the lower and upper respiratory tracts and viral shedding were observed in both macaques. Inoculation of rhesus monkeys with higher doses of the isolate resulted in stronger clinical symptoms of influenza. Our results demonstrate that HPAIV isolated from a water bird in Japan is pathogenic in monkeys by experimental inoculation, and provide a new method for HPAIV infection of non-human primate hosts, a good animal model for investigation of HPAIV pathogenicity.

  15. Detection and localization of rabbit hepatitis e virus and antigen in systemic tissues from experimentally intraperitoneally infected rabbits.

    Directory of Open Access Journals (Sweden)

    Jingjing Mao

    Full Text Available Rabbit hepatitis E virus (HEV is a novel genotype of HEV, and is considered to pose a risk of zoonotic transmission. Research into the systemic distribution of rabbit HEV in rabbits during different periods of infection has rarely been reported. To better understand this virus, we infected rabbits with second-passage rabbit HEV via an intraperitoneal route. After inoculation, the infection showed two types, temporary and constant infection. The detection of HEV RNA in the feces varied with time, and serum antigen correlated with fecal HEV RNA. Viremia only appeared 72 days after inoculation. The rabbits remained antibody negative throughout the experimental period. When HEV was localized, several organs besides the liver were HEV RNA positive. Tissue antigen was observed immunohistochemically in the different cells of various organs, especially in parts of the small intestine and the characteristic rabbit gut-associated lymphoid tissue. These data provide valuable information for future research into the pathogenesis of HEV.

  16. Sympatric and allopatric experimental infections of the planorbid snail Gyraulus chinensis with miracidia of Euparyphium albuferensis (Trematoda: Echinostomatidae).

    Science.gov (United States)

    Muñoz-Antoli, C; Marín, A; Trelis, M; Toledo, R; Esteban, J-G

    2010-12-01

    An experimental infection with echinostomatid miracidia in sympatric or 'local' vs. allopatric or 'away' snail combinations, as a model to examine parasite compatibility, was carried out. We employed Euparyphium albuferensis miracidia to infect Gyraulus chinensis snails, from three different natural parks: Albufera (Valencia, Spain); the Ebro Delta (Tarragona, Spain) and Coto de Doñana (Huelva, Spain). Insignificant differences between the three snail strains were noted for the infection rate and the rhythm of daily cercarial production. However, a significantly higher total cercarial production per snail, patent period and life span were observed in local snails. The different infection characteristics in the three G. chinensis strains considered reveal that E. albuferensis miracidia demonstrate local adaptation.

  17. A Potent Virus-Specific Antibody-Secreting Cell Response to Acute Enterovirus 71 Infection in Children.

    Science.gov (United States)

    Huang, Kuan-Ying Arthur; Lin, Jainn-Jim; Chiu, Cheng-Hsun; Yang, Shuan; Tsao, Kuo-Chien; Huang, Yhu-Chering; Lin, Tzou-Yien

    2015-09-01

    Enterovirus 71 (EV71) remains a leading pathogen for acute infectious diseases in children, especially in Asia. The cellular basis for establishing a virus-specific antibody response to acute EV71 infections is unclear in children. We studied the magnitude of virus-specific antibody-secreting B cells (ASCs) and its relationship with serological response, clinical parameters, and virological parameters among children with laboratory-confirmed EV71 infection. A potent EV71 genogroup B- and virus-specific ASC response was detected in the first week of illness among genotype B5 EV71-infected children. The cross-reactive EV71-specific ASC response to genogroup C viral antigens composed about 10% of the response. The EV71-specific ASC response in children aged ≥3 years produced immunoglobulin G predominantly, but immunoglobulin M was predominant in younger children. Proliferation marker was expressed by the majority of circulating ASCs in the acute phase of EV71 infection. Virus-specific ASC responses significantly correlated with throat viral load, fever duration, and serological genogroup-specific neutralization titer. The presence of a virus-specific ASC response serves an early cellular marker of an EV71-specific antibody response. Further detailed study of EV71-specific ASCs at the monoclonal level is crucial to delineate the specificity and function of antibody immunity in children. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  18. Neuropathogenesis of a highly pathogenic avian influenza virus (H7N1 in experimentally infected chickens

    Directory of Open Access Journals (Sweden)

    Chaves Aida J

    2011-10-01

    Full Text Available Abstract In order to understand the mechanism of neuroinvasion of a highly pathogenic avian influenza virus (HPAIV into the central nervous system (CNS of chickens, specific pathogen free chickens were inoculated with a H7N1 HPAIV. Blood, cerebrospinal fluid (CSF, nasal cavity and brain tissue samples were obtained from 1 to 4 days post-inoculation (dpi of infected and control chickens. Viral antigen topographical distribution, presence of influenza A virus receptors in the brain, as well as, the role of the olfactory route in virus CNS invasion were studied using different immunohistochemistry techniques. Besides, viral RNA load in CSF and blood was quantified by means of a quantitative real-time reverse transcription-polymerase chain reaction. Viral antigen was observed widely distributed in the CNS, showing bilateral and symmetrical distribution in the nuclei of the diencephalon, mesencephalon and rhombencephalon. Viral RNA was detected in blood and CSF at one dpi, indicating that the virus crosses the blood-CSF-barrier early during infection. This early dissemination is possibly favoured by the presence of Siaα2,3 Gal and Siaα2,6 Gal receptors in brain vascular endothelial cells, and Siaα2,3 Gal receptors in ependymal and choroid plexus cells. No viral antigen was observed in olfactory sensory neurons, while the olfactory bulb showed only weak staining, suggesting that the virus did not use this pathway to enter into the brain. The sequence of virus appearance and the topographical distribution of this H7N1 HPAIV indicate that the viral entry occurs via the haematogenous route, with early and generalized spreading through the CSF.

  19. Neuropathogenesis of a highly pathogenic avian influenza virus (H7N1) in experimentally infected chickens.

    Science.gov (United States)

    Chaves, Aida J; Busquets, Núria; Valle, Rosa; Rivas, Raquel; Vergara-Alert, Júlia; Dolz, Roser; Ramis, Antonio; Darji, Ayub; Majó, Natàlia

    2011-10-07

    In order to understand the mechanism of neuroinvasion of a highly pathogenic avian influenza virus (HPAIV) into the central nervous system (CNS) of chickens, specific pathogen free chickens were inoculated with a H7N1 HPAIV. Blood, cerebrospinal fluid (CSF), nasal cavity and brain tissue samples were obtained from 1 to 4 days post-inoculation (dpi) of infected and control chickens. Viral antigen topographical distribution, presence of influenza A virus receptors in the brain, as well as, the role of the olfactory route in virus CNS invasion were studied using different immunohistochemistry techniques. Besides, viral RNA load in CSF and blood was quantified by means of a quantitative real-time reverse transcription-polymerase chain reaction. Viral antigen was observed widely distributed in the CNS, showing bilateral and symmetrical distribution in the nuclei of the diencephalon, mesencephalon and rhombencephalon. Viral RNA was detected in blood and CSF at one dpi, indicating that the virus crosses the blood-CSF-barrier early during infection. This early dissemination is possibly favoured by the presence of Siaα2,3 Gal and Siaα2,6 Gal receptors in brain vascular endothelial cells, and Siaα2,3 Gal receptors in ependymal and choroid plexus cells. No viral antigen was observed in olfactory sensory neurons, while the olfactory bulb showed only weak staining, suggesting that the virus did not use this pathway to enter into the brain. The sequence of virus appearance and the topographical distribution of this H7N1 HPAIV indicate that the viral entry occurs via the haematogenous route, with early and generalized spreading through the CSF.

  20. Persistence of Circulating Hepatitis C Virus Antigens-Specific Immune Complexes in Patients with Resolved HCV Infection.

    Science.gov (United States)

    Hu, Ke-Qin; Cui, Wei

    2018-05-01

    Our recent study indicated the possible presence of detectable hepatitis C virus antigens (HCV-Ags) after denaturation of sera with resolved HCV (R-HCV) infection. The present study determined and characterized persistent HCV-Ags-specific immune complexes (ICs) in these patients. Sixty-eight sera with R-HCV and 34 with viremic HCV (V-HCV) infection were tested for free and IC-bound HCV-Ags using HCV-Ags enzyme immunoassay (EIA), the presence of HCV-Ags-specific ICs by immunoprecipitation and Western blot (IP-WB), HCV ICs containing HCV virions using IP and HCV RNA RT-PCR, and correlation of HCV ICs with clinical presentation in these patients. Using HCV-Ags EIA, we found 57.4% of sera with R-HCV infection were tested positive for bound, but not free HCV-Ags. Using pooled or individual anti-HCV E1/E2, cAg, NS3, NS4b, and/or NS5a to precipitate HCV-specific-Ags, we confirmed persistent HCV-Ags ICs specific to various HCV structural and non-structural proteins not only in V-HCV infection, but also in R-HCV infection. Using IP and HCV RNA PCR, we then confirmed the presence of HCV virions within circulating ICs in V-HCV, but not in R-HCV sera. Multivariable analysis indicated significant and independent associations of persistent circulating HCV-Ags-specific ICs with both age and the presence of cirrhosis in patients with R-HCV infection. Various HCV-Ag-specific ICs, but not virions, persist in 57.4% of patients who had spontaneous or treatment-induced HCV clearance for 6 months to 20 years. These findings enriched our knowledge on HCV pathogenesis and support further study on its long-term clinical relevance, such as extrahepatic manifestation, transfusion medicine, and hepatocarcinogenesis.

  1. Strain Specific Phage Treatment for Staphylococcus aureus Infection Is Influenced by Host Immunity and Site of Infection.

    Directory of Open Access Journals (Sweden)

    Nathan B Pincus

    Full Text Available The response to multi-drug resistant bacterial infections must be a global priority. While mounting resistance threatens to create what the World Health Organization has termed a "post-antibiotic era", the recent discovery that antibiotic use may adversely impact the microbiome adds further urgency to the need for new developmental approaches for anti-pathogen treatments. Methicillin-resistant Staphylococcus aureus (MRSA, in particular, has declared itself a serious threat within the United States and abroad. A potential solution to the problem of antibiotic resistance may not entail looking to the future for completely novel treatments, but instead looking into our history of bacteriophage therapy. This study aimed to test the efficacy, safety, and commercial viability of the use of phages to treat Staphylococcus aureus infections using the commercially available phage SATA-8505. We found that SATA-8505 effectively controls S. aureus growth and reduces bacterial viability both in vitro and in a skin infection mouse model. However, this killing effect was not observed when phage was cultured in the presence of human whole blood. SATA-8505 did not induce inflammatory responses in peripheral blood mononuclear cultures. However, phage did induce IFN gamma production in primary human keratinocyte cultures and induced inflammatory responses in our mouse models, particularly in a mouse model of chronic granulomatous disease. Our findings support the potential efficacy of phage therapy, although regulatory and market factors may limit its wider investigation and use.

  2. Strain Specific Phage Treatment for Staphylococcus aureus Infection Is Influenced by Host Immunity and Site of Infection.

    Science.gov (United States)

    Pincus, Nathan B; Reckhow, Jensen D; Saleem, Danial; Jammeh, Momodou L; Datta, Sandip K; Myles, Ian A

    2015-01-01

    The response to multi-drug resistant bacterial infections must be a global priority. While mounting resistance threatens to create what the World Health Organization has termed a "post-antibiotic era", the recent discovery that antibiotic use may adversely impact the microbiome adds further urgency to the need for new developmental approaches for anti-pathogen treatments. Methicillin-resistant Staphylococcus aureus (MRSA), in particular, has declared itself a serious threat within the United States and abroad. A potential solution to the problem of antibiotic resistance may not entail looking to the future for completely novel treatments, but instead looking into our history of bacteriophage therapy. This study aimed to test the efficacy, safety, and commercial viability of the use of phages to treat Staphylococcus aureus infections using the commercially available phage SATA-8505. We found that SATA-8505 effectively controls S. aureus growth and reduces bacterial viability both in vitro and in a skin infection mouse model. However, this killing effect was not observed when phage was cultured in the presence of human whole blood. SATA-8505 did not induce inflammatory responses in peripheral blood mononuclear cultures. However, phage did induce IFN gamma production in primary human keratinocyte cultures and induced inflammatory responses in our mouse models, particularly in a mouse model of chronic granulomatous disease. Our findings support the potential efficacy of phage therapy, although regulatory and market factors may limit its wider investigation and use.

  3. Experimental infection of octopus vulgaris (Cuvier, 1797) with Photobacterium damsela subsp. piscicida. Immunohistochemical tracking of antigen and tissue responses.

    Science.gov (United States)

    Bakopoulos, Vasileios; White, Daniella; Valsamidis, Michail-Aggelos; Vasilaki, Feli

    2017-03-01

    Adult common octopus individuals were intramuscularly infected with Photobacterium damsela subsp. piscicida in order to investigate if this species is sensitive to this common and important fish pathogen. The fate of the bacterial antigens and the tissue responses of Octopus vulgaris were studied employing immunohistochemical techniques. Strong reaction at the site of injection was evident from day 2 post-infection that continued until day 14. Great numbers of hemocytes that were attracted at the site of infection were involved in phagocytosis of bacteria. Very early in the infection, a transition of cells to fibroblasts and an effort to isolate the infection was observed. During the course of the study, very large necrotic cells were seen at the site of infection, whereas during the later stages hemocytes with phagocytosed bacteria were observed in well-defined pockets inside the muscle tissue. None of the internal organs tested for the presence of the bacterium were positive with the exception of the digestive gland where antigen staining was observed which was not associated with hemocyte infiltration. The high doses of bacterial cells used in this experimental infection and the lack of disease signs from Octopus vulgaris suggest that, under normal conditions, octopus is resistant to Photobacterium damsela subsp. piscicida. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Intra-uterine experimental infection by Ureaplasma diversum induces TNF-α mediated womb inflammation in mice

    Directory of Open Access Journals (Sweden)

    Jamile R. Silva

    2016-01-01

    Full Text Available Ureaplasma diversum is an opportunistic pathogen associated with uterine inflammation, impaired embryo implantation, infertility, abortions, premature birth of calves and neonatal pneumonia in cattle. It has been suggested that the intra-uterine infection by Ureaplasma diversum can cause vascular changes that hinder the success of pregnancy. Thus, the aim of this study was to evaluate the changes of intrauterine site of A/J mice in estrus or proestrus phase inoculated with Ureaplasma diversum. The infection was monitored at 24, 48 and 72 hours by the PCR methodology to detect the Ureaplasma in the inoculation site and the profile of circulating blood cells. Morphological changes, intensity of inflammation and the production of cytokines were compared. The infected mice showed local inflammation through the production of IFN-γ and TNF-α. Ureaplasma diversum infections in the reproductive tract of studied mice seemed to be associated with the production of pro-inflammatory cytokines in uterine parenchyma. The levels of TNF-α of infected mice were dependent on the bacterial load of inoculated Ureaplasma. Uterine experimental infections by Ureaplasma diversum have not been mentioned yet and herein we presented the first report of an intrauterine infection model in mice.

  5. Intra-uterine experimental infection by Ureaplasma diversum induces TNF-α mediated womb inflammation in mice.

    Science.gov (United States)

    Silva, Jamile R; Ferreira, Lício F A A; Oliveira, Percíllia V S; Nunes, Ivanéia V; Pereira, Ítalo S; Timenetsky, Jorge; Marques, Lucas M; Figueiredo, Tiana B; Silva, Robson A A

    2016-01-01

    Ureaplasma diversum is an opportunistic pathogen associated with uterine inflammation, impaired embryo implantation, infertility, abortions, premature birth of calves and neonatal pneumonia in cattle. It has been suggested that the intra-uterine infection by Ureaplasma diversum can cause vascular changes that hinder the success of pregnancy. Thus, the aim of this study was to evaluate the changes of intrauterine site of A/J mice in estrus or proestrus phase inoculated with Ureaplasma diversum. The infection was monitored at 24, 48 and 72 hours by the PCR methodology to detect the Ureaplasma in the inoculation site and the profile of circulating blood cells. Morphological changes, intensity of inflammation and the production of cytokines were compared. The infected mice showed local inflammation through the production of IFN-γ and TNF-α. Ureaplasma diversum infections in the reproductive tract of studied mice seemed to be associated with the production of pro-inflammatory cytokines in uterine parenchyma. The levels of TNF-α of infected mice were dependent on the bacterial load of inoculated Ureaplasma. Uterine experimental infections by Ureaplasma diversum have not been mentioned yet and herein we presented the first report of an intrauterine infection model in mice.

  6. The effect of a fenbendazole treatment on cyst excretion and weight gain in calves experimentally infected with Giardia duodenalis.

    Science.gov (United States)

    Geurden, Thomas; Vandenhoute, Els; Pohle, Herbert; Casaert, Stijn; De Wilde, Nathalie; Vercruysse, Jozef; Claerebout, Edwin

    2010-04-19

    A total of 28 Holstein-Friesian calves were experimentally infected with 10(5)Giardia duodenalis cysts. Eleven days later, all animals were allocated into two groups of 14 animals each, based on the average pre-treatment cyst counts. Treatment was randomly assigned to one of the two groups, and all animals in the treatment group received a daily oral dosage of 15mg fenbendazole per kg bodyweight during 3 consecutive days. The calves in the control group received a placebo (water). From 3 days after treatment onwards, cyst excretion was determined three times a week during 4 consecutive weeks. The faecal consistency and general health were recorded on a daily basis, and all animals were weighed prior to treatment and weekly thereafter. At the end of the experimental period, there was a significant (Pfenbendazole treated and untreated calves experimentally infected with G. duodenalis, although additional data need to confirm the need for treatment in natural conditions.

  7. Prostate specific antigen enhances the innate defence of prostatic epithelium against Escherichia coli infection.

    Science.gov (United States)

    Townes, Claire L; Ali, Ased; Gross, Naomi; Pal, Deepali; Williamson, Stuart; Heer, Rakesh; Robson, Craig N; Pickard, Robert S; Hall, Judith

    2013-10-01

    This study investigated whether the increase in serum prostate specific antigen (PSA) typically seen during male urinary tract infection (UTI) is incidental or reflects an innate defence mechanism of the prostate. The protective roles of the whey-acid-motif-4-disulphide core (WFDC) proteins, secretory leukoproteinase inhibitor (SLPI) and WFDC2, in the prostate were also examined. UTI recurrence was assessed retrospectively in men following initial UTI by patient interview. PSA, SLPI, and WFDC2 gene expression were assessed using biopsy samples. LNCaP and DU145 in vitro prostate cell models were utilized to assess the effects of an Escherichia coli challenge on PSA and WFDC gene expression, and bacterial invasion of the prostate epithelium. The effects of PSA on WFDC antimicrobial properties were studied using recombinant peptides and time-kill assays. Men presenting with PSA >4 ng/ml at initial UTI were less likely to have recurrent (r) UTI than those with PSA prostatic epithelium, and the PSA and SLPI proteins co-localized in vivo. Challenging LNCaP (PSA-positive) cells with E. coli increased PSA, SLPI, and WFDC2 gene expression (P prostate innate defences. Copyright © 2013 Wiley Periodicals, Inc.

  8. Putative biomarkers for evaluating antibiotic treatment: an experimental model of porcine Actinobacillus pleuropneumoniae infection

    DEFF Research Database (Denmark)

    Lauritzen, B.; Lykkesfeldt, J.; Skaanild, M.T.

    2003-01-01

    Biomarkers of infection were screened for their possible role as evaluators of antibiotic treatment in an aerosol infection model of porcine pneumonia caused by Actinobacillus pleuropneumoniae (Ap). Following infection of 12 pigs, clinical signs of pneumonia developed within 20 h, whereafter...... antibiotic treatment of acute Ap-infection ill pigs. The present model provides a valuable tool in the evaluation of antibiotic treatments, offering the advantage of clinical and pathological examinations combined with the use of biochemical infection markers....... recovered clinically within 24h after treatment, whereas tiamulin-treated animals remained clinically ill until the end of the study, 48 h after treatment. A similar Picture was seen for the biomarkers of infection. During the infection period, plasma C-reactive protein (CRP), interleukin-6 and haptoglobin...

  9. Hyperinducibility of Ia antigen on astrocytes correlates with strain-specific susceptibility to experimental autoimmune encephalomyelitis

    International Nuclear Information System (INIS)

    Massa, P.T.; ter Meulen, V.; Fontana, A.

    1987-01-01

    In search of a phenotypic marker determining genetically controlled susceptibility to delayed-type hypersensitivity (DTH) reactions in the brain-in particular, experimental autoimmune encephalomyelitis (EAE)- the authors have compared the γ-interferon (IFN-γ) induction of Ia molecules on astrocytes and macrophages from rat and mouse strains that are susceptible or resistant to this disease. They focused on Ia expression because DTH reactions to self or foreign antigens are largely mediated by lymphocytes restricted by class II (Ia) antigens of the major histocompatibility complex (MHC). The data demonstrate that Lewis (fully susceptible) and Brown Norway (BN) (fully resistant) rats are very different in that Lewis astrocytes express much higher levels of Ia than BN astrocytes. Similar data were obtained from an analysis of EAE-susceptible and -resistant mouse strains (SJL and BALB/c, respectively), which suggest that this phenomenon may be universal and not limited to only one mammalian species. At least one gene responsible for Ia hyperinduction is located outside the rat RT-1 or the mouse MHC locus. Animals congenic at the RT-1 or MHC locus of the resistant strain but with background genes of the susceptible strain exhibit intermediate levels of Ia compared to fully resistant and susceptible rodents, which fits well with the reduced EAE susceptibility of these congenic animals. Furthermore, hyperinduction of Ia is astrocyte specific, since peritoneal macrophages of susceptible and resistant strains exhibit identical profiles of Ia induction. Thus, astrocyte Ia hyperinducibility may be a major strain- and tissue-specific factor that contributes to Ia-restricted DTH reactions in the brain

  10. Diagnosis of enzootic pneumonia in Danish cattle: reverse transcription-polymerase chain reaction assay for detection of bovine respiratory syncytial virus in naturally and experimentally infected cattle

    DEFF Research Database (Denmark)

    Larsen, Lars Erik; Tjørnehøj, Kirsten; Viuff, B.

    1999-01-01

    A reverse transcription-polymerase chain reaction (RT-PCR) assay was developed for detection of bovine respiratory syncytial virus (BRSV) in lung tissue of naturally and experimentally infected cattle. Primers were selected from the gene coding the F fusion protein, which is relatively conserved......, in addition, 10 animals that were negative with the ELISA were positive with the RT-PCR assay. These results indicates that the RT-PCR assay can be a sensitive, reliable alternative to conventional diagnostic procedures....... among BRSV isolates. The RT-PCR assay was highly specific, it yielded positive reactions only when performed on BRSV-infected cell cultures or tissues. The detection limit of the RT-PCR assay was assessed as 5 TCID50. BRSV was detected in tissues of the respiratory tract and in the tracheobroncheal...

  11. Age-specific haemosporidian infection dynamics and survival in Seychelles warblers

    Science.gov (United States)

    Hammers, Martijn; Komdeur, Jan; Kingma, Sjouke A.; Hutchings, Kimberly; Fairfield, Eleanor A.; Gilroy, Danielle L.; Richardson, David S.

    2016-01-01

    Parasites may severely impact the fitness and life-history of their hosts. After infection, surviving individuals may suppress the growth of the parasite, or completely clear the infection and develop immunity. Consequently, parasite prevalence is predicted to decline with age. Among elderly individuals, immunosenescence may lead to a late-life increase in infection prevalence. We used a 21-year longitudinal dataset from one population of individually-marked Seychelles warblers (Acrocephalus sechellensis) to investigate age-dependent prevalence of the GRW1 strain of the intracellular protozoan blood parasite Haemoproteus nucleocondensus and whether infections with this parasite affect age-dependent survival. We analyzed 2454 samples from 1431 individuals and found that H. nucleocondensus infections could rarely be detected in nestlings. Prevalence increased strongly among fledglings and peaked among older first year birds. Prevalence was high among younger adults and declined steeply until ca 4 years of age, after which it was stable. Contrary to expectations, H. nucleocondensus prevalence did not increase among elderly individuals and we found no evidence that annual survival was lower in individuals suffering from an infection. Our results suggest that individuals clear or suppress infections and acquire immunity against future infections, and provide no evidence for immunosenescence nor an impact of chronic infections on survival. PMID:27431430

  12. Efficacy of Mycoplasma hyopneumoniae vaccination before and at weaning against experimental challenge infection in pigs.

    Science.gov (United States)

    Arsenakis, Ioannis; Panzavolta, Luca; Michiels, Annelies; Del Pozo Sacristán, Rubén; Boyen, Filip; Haesebrouck, Freddy; Maes, Dominiek

    2016-03-29

    Commercial bacterins are widely used at weaning to control Mycoplasma hyopneumoniae infections in pigs. However, it is not known whether the efficacy of vaccinating against M. hyopneumoniae can be influenced by the weaning process when vaccination is applied at the day of weaning. The present study assessed the efficacy of a single M. hyopneumoniae vaccination (Ingelvac MycoFLEX®) three days before weaning (V1) or at weaning (V2) against experimental challenge infection. Four weeks after vaccination, groups V1 and V2 (n = 20 pigs each) and a non-vaccinated, positive control group (PCG) (n = 20) were endotracheally inoculated with a virulent M. hyopneumoniae field strain. Five pigs were used as a negative control group. All pigs were euthanized 5 weeks after challenge. The main parameters investigated included macroscopic and histopathological lung lesions at necropsy, immunofluorescence (IF) staining and quantitative real-time PCR (qPCR) on broncho-alveolar lavage (BAL) fluid for quantifying M. hyopneumoniae. The average macroscopic lung lesion scores in groups V1, V2 and PCG were 0.54, 0.88 and 1.04, respectively (P > 0.05). The average lymphohistiocytic infiltration scores in groups V1, V2 and PCG were 2.95, 3.16 and 3.61, respectively (P 0.05), the qPCR values were: V1 = 10(2.94), V2 = 10(2.76) and PCG = 10(3.23) (P > 0.05). All pigs of the negative control group remained negative throughout the study. Both vaccinated groups had lower numbers of macroscopic and histopathological lung lesions, and lower numbers of M. hyopneumoniae organisms in the BAL fluid compared to the PCG. However, no firm conclusions could be made on whether weaning negatively influences the efficacy of M. hyopneumoniae vaccination, since significant differences between the treatment groups were only obtained for the histopathological lung lesions. This could be attributed to the fact that milder macroscopic lung lesions were produced in the inoculated pigs, when compared to previous

  13. Adoptive transfer of EBV specific CD8+ T cell clones can transiently control EBV infection in humanized mice.

    Directory of Open Access Journals (Sweden)

    Olga Antsiferova

    2014-08-01

    Full Text Available Epstein Barr virus (EBV infection expands CD8+ T cells specific for lytic antigens to high frequencies during symptomatic primary infection, and maintains these at significant numbers during persistence. Despite this, the protective function of these lytic EBV antigen-specific cytotoxic CD8+ T cells remains unclear. Here we demonstrate that lytic EBV replication does not significantly contribute to virus-induced B cell proliferation in vitro and in vivo in a mouse model with reconstituted human immune system components (huNSG mice. However, we report a trend to reduction of EBV-induced lymphoproliferation outside of lymphoid organs upon diminished lytic replication. Moreover, we could demonstrate that CD8+ T cells against the lytic EBV antigen BMLF1 can eliminate lytically replicating EBV-transformed B cells from lymphoblastoid cell lines (LCLs and in vivo, thereby transiently controlling high viremia after adoptive transfer into EBV infected huNSG mice. These findings suggest a protective function for lytic EBV antigen-specific CD8+ T cells against EBV infection and against virus-associated tumors in extra-lymphoid organs. These specificities should be explored for EBV-specific vaccine development.

  14. Experimental specifications for eutectic reaction between metallic fuel and HT-9

    International Nuclear Information System (INIS)

    Hwang, Woan; Nam, Cheol; Lee, Byoung Oon; Ryu, Woo Seog

    1998-10-01

    The chemical interaction between metallic fuel and cladding is important in designing the fuel pin of the KALIMER. When metal fuel and cladding are contacted, the elements in fuel and cladding are inter-diffuse each other, forming the reaction layers at interface. The reaction layers may cause two important factors in aspects of fuel pin integrity. Firstly, it degrades cladding strength by reducing effective cladding thickness. Secondly, these layers accelerate eutectic reaction at transient conditions. To evaluate these phenomena, the diffusion couple experiment is planned by using metal fuels with various zirconium contents and HT-9 steel. The U-Zr fuel alloys will be used for the experiment with the different zirconium contents, these are 8, 10 and 12 weight %. This experiment aims to evaluate the effects of zirconium content on the chemical reaction. Furthermore, the reaction rate and threshold temperature of the eutectic melting will be determined as a function of the zirconium content. This document describes the detail experimental specifications for the eutectic reaction such as test setup, test requirements and test procedure. (author). 10 refs

  15. Comparison of infectious hematopoietic necrosis in natural and experimental infections of spawning salmonids by infectivity and immunohistochemistry

    Science.gov (United States)

    Yamamoto, T.; Arakawa, C.K.; Batts, W.N.; Winton, J.R.

    1989-01-01

    Infectious hematopoietic necrosis (IHN) continues to be a serious virus disease of salmonids with epizootics recorded in both wild and hatchery populations (Williams and Amend 1976; Carlisle et al 1979; Groberg and Fryer 1983; Saft and Pratt 1986; Traxler 1987; Follett et al 1987; Meyers et al 1988). While originally enzootic in western North America, the virus appears to be spreading further (Sano et al 1977; de Kinkelin et al 1987; Bovo et al 1987). In hatchery outbreaks occurring in regions where the virus is not enzootic, it is often possible to trace the virus to the importation of infected fingerlings or contaminated eggs. In regions where the virus is widespread among stocks of fish, the source of virus infection is more difficult to establish particularly in watersheds where there are anadromous salmonids. Although salmonid fish surviving infection as fry and returning from the ocean to spawn are considered to be parental carriers of IHNV, there is very little data to support this hypothesis. Amend (1975) in the study of rainbow trout reported that in a population surviving infection and assayed a few years later found that a few trout were carrying virus. This is the study often cited as evidence for the carrier status of returning salmonids. LaPatra et al (1987) presented data that indicated IHNV has been transmitted horizontally through water from adult chinook salmon (Oncorhynchus tshawytscha) to adult coho salmon (O. kisutch) at a hatchery in northern California. They suggested that horizontal transmission may be an important means for perpetuating IHN. However, the actual mechanisms for persistence and transmission of IHN among fish in a watershed is likely to be complex and involve multiple species and age groups as well as intermediate vectors and/or reservoirs.

  16. Quasispecies evolution of the prototypical genotype 1 porcine reproductive and respiratory syndrome virus early during in vivo infection is rapid and tissue specific.

    Science.gov (United States)

    Lu, Zen H; Wang, Xinglong; Wilson, Alison D; Dorey-Robinson, Daniel L W; Archibald, Alan L; Ait-Ali, Tahar; Frossard, Jean-Pierre

    2017-08-01

    Porcine reproductive and respiratory syndrome virus (PRRSV) is a major infectious threat to the pig industry worldwide. Increasing evidence suggests that microevolution within a quasispecies population can give rise to high sequence heterogeneity in PRRSV; potentially impacting the pathogenicity of the virus. Here, we report on micro-evolutionary events taking place within the viral quasispecies population in lung and lymph node 3 days post infection (dpi) following experimental in vivo infection with the prototypical Lelystad PRRSV (LV). Sequence analysis revealed 16 high frequency single nucleotide variants (SNV) or differences from the reference LV genome which are assumed to be representative of the consensus inoculum genome. Additionally, 49 other low frequency SNVs were also found in the inoculum population. At 3 dpi, a total of 9 and 10 SNVs of varying frequencies could already be detected in the LV population infecting the lung and lymph nodes, respectively. Interestingly, of these, three and four novel SNVs emerged independently in the two respective tissues when compared to the inoculum. The remaining variants, though already present at lower frequencies in the inoculum, were positively selected and their frequency increased within the quasispecies population. Hence, we were able to determine directly from tissues infected with PRRSV the repertoire of genetic variants within the viral quasispecies population. Our data also suggest that microevolution of these variants is rapid and some may be tissue-specific.

  17. The expression and evolution of virulence in multiple infections: the role of specificity, relative virulence and relative dose.

    Science.gov (United States)

    Ben-Ami, Frida; Routtu, Jarkko

    2013-05-03

    Multiple infections of the same host by different strains of the same microparasite species are believed to play a crucial role during the evolution of parasite virulence. We investigated the role of specificity, relative virulence and relative dose in determining the competitive outcome of multiple infections in the Daphnia magna-Pasteuria ramosa host-parasite system. We found that infections by P. ramosa clones (single genotype) were less virulent and produced more spores than infections by P. ramosa isolates (possibly containing multiple genotypes). We also found that two similarly virulent isolates of P. ramosa differed considerably in their within-host competitiveness and their effects on host offspring production when faced with coinfecting P. ramosa isolates and clones. Although the relative virulence of a P. ramosa isolate/clone appears to be a good indicator of its competitiveness during multiple infections, the relative dose may alter the competitive outcome. Moreover, spore counts on day 20 post-infection indicate that the competitive outcome is largely decided early in the parasite's growth phase, possibly mediated by direct interference or apparent competition. Our results emphasize the importance of epidemiology as well as of various parasite traits in determining the outcome of within-host competition. Incorporating realistic epidemiological and ecological conditions when testing theoretical models of multiple infections, as well as using a wider range of host and parasite genotypes, will enable us to better understand the course of virulence evolution.

  18. Performance of the ELISA test for the diagnosis of cysticercosis using experimentally and naturally cattle infected with metacestode of Taenia saginata

    Directory of Open Access Journals (Sweden)

    Rafaella Paola Meneguete dos Guimarães-Peixoto

    2015-04-01

    Full Text Available The bovine taeniasis-cysticercosis complex can be defined as a set of pathological changes caused by the adult form of Taenia saginata in humans and their larval form in animals (Cysticercus bovis. Data on the occurrence of bovine cysticercosis comes from the records of veterinary inspection of meat in slaughterhouses under fiscalization, where some positive cases may go unnoticed, especially in moderate infections. So, it is relevant the use of serological tests that have greater sensitivity than the post-mortem routine exams. Studies have shown the possible application of the ELISA test as a tool for epidemiological studies of the parasitosis and in the identification of animals with cysts. The aim of this study is to determine the detection threshold of the indirect ELISA test, using experimentally and naturally infected animals in detecting cases of cysticercosis. The sensitivity of the test to naturally infected animals using a cut-off 1 and 2 added with 2 standart-deviation (SD was of 12% and 24.4%, respectively. However, when using the cut-off of 1 and 2 added with 3 SD, the test sensitivity dropped, represented by 14.4% and 1.99% of the test sensitivity. As for the samples from experimentally infected animals, using the cut-off 1 and 2 added with 2 SD the sensitivity was 55.9% and 92.5%; and adding 3 SD the values found were 31.2% and 86%, respectively. The specificity of the test in all situations tested was 100%. It is important to take into account the right choice of control sera used in the ELISA test, whereas, according to its application, it is necessary to increase the sensitivity or specificity.

  19. Experimental mixed infection of Leishmania (Leishmania) amazonensis and Leishmania (L.) infantum in hamsters (Mesocricetus auratus).

    Science.gov (United States)

    DE Lima Celeste, Jordanna Luíza; Venuto Moura, Ana Paula; França-Silva, João Carlos; Matos DE Sousa, Gabriela; Oliveira Silva, Soraia; Norma Melo, Maria; Luiz Tafuri, Wagner; Carvalho Souza, Carolina; Monteiro DE Andrade, Hélida

    2017-08-01

    In South America, visceral leishmaniasis is frequently caused by Leishmania infantum and, at an unknown frequency, by Leishmania amazonensis. Therefore, mixed infections with these organisms are possible. Mixed infections might affect the clinical course, immune response, diagnosis, treatment and epidemiology of the disease. Here we describe the clinical course of mixed infections with L. amazonensis and L. infantum in a hamster model. We show that mixed infections are associated with more severe clinical disease than infection with L. amazonensis or L. infantum alone. In spleens with mixed infections, L. infantum outcompeted L. amazonensis in the tissue, but not in culture from tissue. We found increased levels of IgG in animals infected with L. infantum. Although more than 30 bands were revealed in a Western blot, the highest immunogenicity was observed with proteins having molecular masses of 95 and 90 kDa, whereas proteins with molecular masses of lower than 50 kDa were reactive frequently with serum from hamsters infected with L. amazonensis, and proteins with molecular masses of 80 and 70 kDa were reactive only with serum from hamsters infected with L. infantum. This finding has important implications regarding the biology of Leishmania and humoral immune responses to infections with these organisms.

  20. Tissue-specific down-regulation of RIPK 2 in Mycobacterium leprae-infected nu/nu mice

    Directory of Open Access Journals (Sweden)

    Gue-Tae Chae

    1992-01-01

    Full Text Available RIPK 2 is adapter molecule in the signal pathway involved in Toll-like receptors. However, there has been no reported association between receptor-interacting serine/threonine kinase 2 (RIPK 2 expression and the infectious diseases involving mycobacterial infection. This study found that its expression was down-regulated in the footpads and skin but was up-regulated in the liver of Mycobacterium leprae-infected nu/nu mice compared with those of the M. leprae non-infected nu/nu mice. It was observed that the interlukin-12p40 and interferon-γ genes involved in the susceptibility of M. leprae were down-regulated in the skin but were up-regulated in the liver. Overall, this suggests that regulation of RIPK 2 expression is tissue-specifically associated with M. leprae infection.

  1. Plasmablasts During Acute Dengue Infection Represent a Small Subset of a Broader Virus-specific Memory B Cell Pool

    Directory of Open Access Journals (Sweden)

    Ramapraba Appanna

    2016-10-01

    Full Text Available Dengue is endemic in tropical countries worldwide and the four dengue virus serotypes often co-circulate. Infection with one serotype results in high titers of cross-reactive antibodies produced by plasmablasts, protecting temporarily against all serotypes, but impairing protective immunity in subsequent infections. To understand the development of these plasmablasts, we analyzed virus-specific B cell properties in patients during acute disease and at convalescence. Plasmablasts were unrelated to classical memory cells expanding in the blood during early recovery. We propose that only a small subset of memory B cells is activated as plasmablasts during repeat infection and that plasmablast responses are not representative of the memory B cell repertoire after dengue infection.

  2. Histopathological and parasitological investigations of ear healthy skin of dogs naturally and experimentally infected with Leishmania (Leishmania) chagasi.

    Science.gov (United States)

    Figueiredo, Maria Marta; Moura, Eliane Perlatto; Costa, Miriam Maria; Ribeiro, Vitor Marcio; Michalick, Marilene Suzan; Tafuri, Washington Luiz; Tafuri, Wagner Luiz

    2010-07-01

    Although 90% of clinical cases of American visceral leishmaniasis (AVL) occur in the northeastern region of Brazil, the incidence of cases in recent years has increased in southeastern states such as Minas Gerais (MG), where the disease has been reported in several cities, including Belo Horizonte, the state capital. Some studies have shown a strong correlation between the incidence of AVL and canine visceral leishmaniasis (CVL) in Belo Horizonte. A study of 108 dogs with parasite Leishmania chagasi detected by immuno-histochemistry in healthy ear skin was obtained from two distinct geographical areas: 55 from a metropolitan area of the municipality (Santa Luzia, MG) and 53 dogs from a central area of Belo Horizonte. In parallel, a group of 10 beagles were experimentally infected with L. chagasi. Considering the clinical aspects of all naturally infected dogs, symptomatic dogs were more frequent than asymptomatic ones, especially animals from the metropolitan area compared with the central area (79.6% and 20.3%, respectively). A chronic exudate was observed in the ear of 51 out of 55 dogs naturally infected from the metropolitan area (92.7%) and 45 out of 53 dogs naturally infected from the central area (84.9%). Importantly, asymptomatic dogs from the central area harbor more parasites in the skin than the asymptomatic ones from the metropolitan area. In addition, a profound difference was noted in the intensity of the inflammatory reaction and parasite load in the skin of experimental infected dogs.

  3. Type-specific identification of anogenital herpes simplex virus infections by use of a commercially available nucleic acid amplification test.

    Science.gov (United States)

    Van Der Pol, Barbara; Warren, Terri; Taylor, Stephanie N; Martens, Mark; Jerome, Keith R; Mena, Leandro; Lebed, Joel; Ginde, Savita; Fine, Paul; Hook, Edward W

    2012-11-01

    Herpes infections are among the most common sexually transmitted infections (STI), but diagnostic methods for genital herpes have not kept pace with the movement toward molecular testing. Here, we describe an FDA-approved molecular assay that identifies and types herpes simplex virus (HSV) infections for use in routine clinical settings. Paired samples from anogenital lesions were tested using the BD ProbeTec HSV Q(x) (HSVQ(x)) system, HSV culture and, a laboratory-developed PCR assay. Family planning, obstetrics/gynecology (OB/GYN), or sexually transmitted disease (STD) clinics in the United States served as recruitment sites. Sensitivity and specificity estimates, head-to-head comparisons, measures of agreement, and latent-class analyses were performed to provide robust estimates of performance. A total of 508 participants (174 men and 334 women) with anogenital lesions were included; 260 HSV-2 and 73 HSV-1 infections were identified. No differences in test performance based on gender, clinic type, location of the lesion, or type of lesion were observed. The sensitivity of HSV-2 detection ranged from 98.4 to 100% depending on the analytical approach, while the specificity ranged from 80.6%, compared to the less sensitive culture method, to 97.0%, compared to PCR. For HSV-1, the sensitivity and specificity ranges were 96.7 to 100% and 95.1 to 99.4%, respectively. This assay may improve our ability to accurately diagnose anogenital lesions due to herpes infection.

  4. A macro- and light microscopical study of the pathology of Calicophoron microbothrium infection in experimentally infected cattle

    Directory of Open Access Journals (Sweden)

    M. Mavenyengwa

    2005-09-01

    Full Text Available Twelve Tuli weaner steers aged 1 year were randomly subdivided into three groups of four animals and infected with different doses of Calicophoron microbothrium metacercariae. Each animal in Group I received a low dose (LD of 5 000 metacercariae, Group II a medium dose (MD of 15 000 metacercariae, Group III a high dose (HD of 25 000 metacercariae and one additional animal was kept as an uninfected control (C. After infection, one animal from each group was slaughtered on Day 28, 42, 56 and 84 post infection (pi and samples from the ileum, jejunum, duodenum, abomasum and the rumen were collected for histopathological and cytological examination. On Day 28 pi, the gross pathological lesions observed in the duodenum of the LD and the MD animals were similar and comprised duodenal thickening, corrugation, hyperaemia, petechiation and ulceration. In the HD animal the duodenal lesions were similar but more severe. The abomasal folds were severely oedematous in the MD group and nearly occluded the abomasal lumen. Moderate oedema of the abomasal folds was also present in the LD and HD animals. The gross pathological lesions regressed in all the infected groups with increasing age of infection and had disappeared completely by Day 56 pi. On Day 28 pi the histopathological lesions in the duodenum and jejunum of the LD and MD groups were similar, comprising subtotal villous atrophy, hyperplasia of Brunner's glands and Peyer's patches and moderate infiltration of eosinophils, mast cells and a few globule leukocytes, basophils and lymphocytes in the lamina propria. The HD group had total villous atrophy, severe hyperplasia and cystic dilatation of Brunner's glands, which had expanded to cover the entire submucosa. On Day 42 pi the histopathological lesions were still present in the MD and the HD groups comprising subtotal villous atrophy and hyperplasia of Brunner's glands. Heavy infiltrations of eosinophils, moderate amounts of mast cells and a few

  5. CNS recruitment of CD8+ T lymphocytes specific for a peripheral virus infection triggers neuropathogenesis during polymicrobial challenge.

    Directory of Open Access Journals (Sweden)

    Christine M Matullo

    2011-12-01

    Full Text Available Although viruses have been implicated in central nervous system (CNS diseases of unknown etiology, including multiple sclerosis and amyotrophic lateral sclerosis, the reproducible identification of viral triggers in such diseases has been largely unsuccessful. Here, we explore the hypothesis that viruses need not replicate in the tissue in which they cause disease; specifically, that a peripheral infection might trigger CNS pathology. To test this idea, we utilized a transgenic mouse model in which we found that immune cells responding to a peripheral infection are recruited to the CNS, where they trigger neurological damage. In this model, mice are infected with both CNS-restricted measles virus (MV and peripherally restricted lymphocytic choriomeningitis virus (LCMV. While infection with either virus alone resulted in no illness, infection with both viruses caused disease in all mice, with ∼50% dying following seizures. Co-infection resulted in a 12-fold increase in the number of CD8+ T cells in the brain as compared to MV infection alone. Tetramer analysis revealed that a substantial proportion (>35% of these infiltrating CD8+ lymphocytes were LCMV-specific, despite no detectable LCMV in CNS tissues. Mechanistically, CNS disease was due to edema, induced in a CD8-dependent but perforin-independent manner, and brain herniation, similar to that observed in mice challenged intracerebrally with LCMV. These results indicate that T cell trafficking can be influenced by other ongoing immune challenges, and that CD8+ T cell recruitment to the brain can trigger CNS disease in the apparent absence of cognate antigen. By extrapolation, human CNS diseases of unknown etiology need not be associated with infection with any particular agent; rather, a condition that compromises and activates the blood-brain barrier and adjacent brain parenchyma can render the CNS susceptible to pathogen-independent immune attack.

  6. Experimentally induced intravaginal Tritrichomonas foetus infection in a mouse model Infecção experimental intravaginal com Tritricho-monas foetus em modelo camundongo

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    Pedro Soto

    2005-12-01

    Full Text Available The interest to develop research on the host-parasite relationship in bovine tritrichomonosis has accomplished the use of experimental models alternative to cattle. The BALB/c mouse became the most appropriate species susceptible to vaginal Tritrichomonas foetus infection requiring previous estrogenization. For the need of an experimental model without persistent estrogenization and with normal estrous cycles, the establishment and persistence of vaginal infection on BALB/c mouse with different concentrations of T. foetus in two experimental groups was evaluated. Group A was treated with 5mg of b-estradiol 3-benzoate to synchronize the estrous, 48 hours before the T. foetus vaginal inoculation, and Group B was inoculated in natural estrus. At 5-7 days after treatment, estrogenic effect decreased allowing all animals to cycle regularly during the experiment. From the first week post-infection, samples of vaginal mucus were taken from all animals during 34 weeks, in order to evaluate the course of infection and the stage of the estrus cycle. Group A showed 93.6% of infected animals, and Group B showed 38%. Different doses of T. foetus were assayed to establish the vaginal infection, with a persistence of 34 weeks. Although different behavior was observed in each subgroup belonging to either Group A or Group B, there were no significant differences among the infecting doses used. The b-estradiol 3-benzoate treatment had a favorable effect on the establishment of the infection (PA necessidade