WorldWideScience

Sample records for experimental infection shows

  1. Coxsackievirus infections in pregnant women with a parallel experimental model infection showing possible effects on coarse of pregnancy

    Directory of Open Access Journals (Sweden)

    Borsanyiova M.

    2011-04-01

    Full Text Available Aim of our work was firstly to determine the prevalence of anti-coxsackievirus antibodies during pregnancy. 217 serum samples were tested for antibodies by virus neutralization test against coxsackieviruses (CV B1–B6, A7 and A9. The second aim was to investigate experimental transmission of virus to the fetus during pregnancy. Methods. Virus Neutralization Test, RT-PCR. Results. In the serological study, paired blood serum samples from 217 pregnant women were studied for antibodies against coxsackievirus serotypes (CVB1–CVB6, CVA7 and CVA9 in sera of pregnant women from selected areas of the Slovak Republic. Coxsackievirus B4 (CVB4 infection was most prevalent, followed by CVB3, CVA7, CVA9, CVB5, CVB2, CVB1 while coxsackievirus B6 (CVB6 was scarce. In 30 out of 217 cases (13.82 % current infection was recorded. In the experimental murine study, in the second week of gravidity we observed presence of enteroviral RNA in the placenta and the intestine of the dead fetuses of the mice. Conclusions. Anti-CV antibodies were prevalent in the pregnant mothers indicating circulation of these viruses in the population. Current infection was shown in 13.82 % of studied cases. Presence of virus RNA in the organs of the unborn fetuses in the experimental infection indicates the possibility of transfer of the coxsackievirus B4-E2 infection from mother to child during antenatal development

  2. Histopathological and immunohistochemical study of exocrine and endocrine pancreatic lesions in avian influenza A experimentally infected turkeys showing evidence of pancreatic regeneration.

    Science.gov (United States)

    Cavicchioli, Laura; Zappulli, Valentina; Beffagna, Giorgia; Caliari, Diego; Zanetti, Rossella; Nordio, Laura; Mainenti, Marta; Frezza, Federica; Bonfante, Francesco; Patrono, Livia Victoria; Capua, Ilaria; Terregino, Calogero

    2015-01-01

    In order to investigate the pancreatic lesions caused by the infection with either H7N1 or H7N3 low-pathogenicity avian influenza viruses, 28 experimentally infected turkeys were submitted for histopathology, immunohistochemistry, haematobiochemistry and real-time reverse transcriptase polymerase chain reaction after different days post-infection (DPI). The localization of viral antigen and the measurement of insulin and glucagon expression in the pancreas were assessed to verify the progression from pancreatitis to metabolic disorders, such as diabetes. At the early infection phase (4-7 DPI), a severe acute necrotizing pancreatitis was recognized. During the intermediate phase (8-17 DPI), a mixed acute/chronic change associated with regenerative ductular proliferation was observed. A loss of pancreatic islets was detected in most severe cases and viral antigen was found in the pancreas of 11/28 turkeys (4-10 DPI) with the most severe histological damage. In turkeys euthanized at 39 DPI (late phase), a chronic fibrosing pancreatitis was observed with the reestablishment of both the exocrine and the endocrine pancreas. Insulin and glucagon expression manifested a progressive decrease with subsequent ductular positivity. Haematobiochemistry revealed increased lipasemia in the first week post-infection and hyperglycaemia in the second, with a progressive normalization within 21 DPI. This study allowed the identification of progressive virus-associated exocrine and endocrine pancreatic damage, suggesting that influenza virus might be responsible for metabolic derangements. Moreover, it highlighted a remarkable post-damage hyperplastic and reparative process from a presumptive common exocrine/endocrine precursor. This potential regeneration deserves further investigation for its relevance in a therapeutic perspective to replace lost and non-functional cells in diabetes mellitus.

  3. Experimentally infected domestic ducks show efficient transmission of Indonesian H5N1 highly pathogenic avian influenza virus, but lack persistent viral shedding.

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    Hendra Wibawa

    Full Text Available Ducks are important maintenance hosts for avian influenza, including H5N1 highly pathogenic avian influenza viruses. A previous study indicated that persistence of H5N1 viruses in ducks after the development of humoral immunity may drive viral evolution following immune selection. As H5N1 HPAI is endemic in Indonesia, this mechanism may be important in understanding H5N1 evolution in that region. To determine the capability of domestic ducks to maintain prolonged shedding of Indonesian clade 2.1 H5N1 virus, two groups of Pekin ducks were inoculated through the eyes, nostrils and oropharynx and viral shedding and transmission investigated. Inoculated ducks (n = 15, which were mostly asymptomatic, shed infectious virus from the oral route from 1 to 8 days post inoculation, and from the cloacal route from 2-8 dpi. Viral ribonucleic acid was detected from 1-15 days post inoculation from the oral route and 1-24 days post inoculation from the cloacal route (cycle threshold <40. Most ducks seroconverted in a range of serological tests by 15 days post inoculation. Virus was efficiently transmitted during acute infection (5 inoculation-infected to all 5 contact ducks. However, no evidence for transmission, as determined by seroconversion and viral shedding, was found between an inoculation-infected group (n = 10 and contact ducks (n = 9 when the two groups only had contact after 10 days post inoculation. Clinical disease was more frequent and more severe in contact-infected (2 of 5 than inoculation-infected ducks (1 of 15. We conclude that Indonesian clade 2.1 H5N1 highly pathogenic avian influenza virus does not persist in individual ducks after acute infection.

  4. Experimental Infection of Sheep using Infective Larvae (L3 ...

    African Journals Online (AJOL)

    Experimental Infection of Sheep using Infective Larvae (L3) harvested from the Faeces of Naturally Infected Swayne's Hartebeest ( Alcelaphus buselaphus swaynei ) at Senkele Swayne's Hartebeest Sanctuary, Ethiopia.

  5. Experimental Trichomonas infection: Morphological aspects

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    E. N. Shumkova

    2016-01-01

    Full Text Available Background. Growth tendency the asymptomatic forms of an urogenital trichomoniasis, frequency of complications from reproductive organs, uncertainty of many aspects of the violations of a spermatogenesis influencing reproductive function all this proves need of search of the urogenital trichomoniasis adequate experimental model. Lack of the corresponding experimental model is limited by our opportunities for carrying out the standardized, controlled researches on studying of transmission, pathogenesis, the immune answer, therapy and development of vaccines at a triсhomonas infection.Objective is studying action of Trichomonas vaginalis on a spermatogenny epithelium the mature of individuals of guinea pigs in the conditions of sharp and chronic experience.Materials and methods. Experiments are made on the “Reproductive System (Guinea Pigs + Trichomonas vaginalis” modeling the natural course of an infection. In experiment 2 groups of animals: 1st (n = 8 – experimental, 2nd (n = 8 – control were formed. Against the background of the reduction of the immune status (hydrocortisone 125 mg/kg intramuscularly 1 time in day during 2 days the animals of the 1st group were injected intraurethral suspension containing 1 × 106 Trichomonas on 0.5 ml of culture medium, the animals of the 2nd group – 0.5 ml of medium. Under the condition of the acute experiment the animals were sacrificed on day 9 (the middle of the cycle of spermatogenesis – I experienced group and on day 30 (full spermatogenic cycle – II experimental group. The control animals were slaughtered in the same period. The material for histological study was prepared by the traditional way.Results. In an experimental model of “Reproductive system (guinea pigs + T. vaginalis”, staging and degree of disturbance of spermatogenesis, depending on the duration of trichomonas infection were shown. So, in acute experience morphological changes correspond to changes in the

  6. PLASMODIUM BERGHEI: CYCLICAL TRANSMISSIONS BY EXPERIMENTALLY INFECTED ANOPHELES QUADRIMACULATUS.

    Science.gov (United States)

    YOELI, M; MOST, H; BONE, G

    1964-06-26

    A number of strains of Plasmodium berghei were isolated from sporozoites of Anopheles dureni. Laboratory-bred Anopheles quadrimaculatus fed on carriers of the newly isolated strains showed overwhelming midgut infections and moderate or mild salivary gland infections. Successive cyclic transmissions by the bite of experimentally infected A. quadrimaculatus in laboratorybred tree rats (Thamnomys surdaster) were carried out.

  7. Experimental Ascaris suum infection in Yankasa lambs ...

    African Journals Online (AJOL)

    The effects of experimental Ascaris suum infection in Yankasa lambs were investigated. Twenty four (24) Yankasa lambs aged 6-8 months were purchased and randomly divided into two groups (1 and 2). The lambs in group 1, consisting of 16 animals, were orally infected with 1500 infective A. suum eggs daily for seven ...

  8. PMWS: Experimental model and co-infections

    DEFF Research Database (Denmark)

    Allan, G. M.; McNeilly, F.; Ellis, J

    2004-01-01

    and pneumonia and typical histological lesions include lymphocytic depletion and multinucleated giant cell formation in lymph nodes, degeneration and necrosis of hepatocytes, and multifocal lymphohistocytic interstitial pneumonia. This communication will review the results of experimental infections...

  9. Rhinovirus genome evolution during experimental human infection.

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    Samuel Cordey

    Full Text Available Human rhinoviruses (HRVs evolve rapidly due in part to their error-prone RNA polymerase. Knowledge of the diversity of HRV populations emerging during the course of a natural infection is essential and represents a basis for the design of future potential vaccines and antiviral drugs. To evaluate HRV evolution in humans, nasal wash samples were collected daily for five days from 15 immunocompetent volunteers experimentally infected with a reference stock of HRV-39. In parallel, HeLa-OH cells were inoculated to compare HRV evolution in vitro. Nasal wash in vivo assessed by real-time PCR showed a viral load that peaked at 48-72 h. Ultra-deep sequencing was used to compare the low-frequency mutation populations present in the HRV-39 inoculum in two human subjects and one HeLa-OH supernatant collected 5 days post-infection. The analysis revealed hypervariable mutation locations in VP2, VP3, VP1, 2C and 3C genes and conserved regions in VP4, 2A, 2B, 3A, 3B and 3D genes. These results were confirmed by classical sequencing of additional samples, both from inoculated volunteers and independent cell infections, and suggest that HRV inter-host transmission is not associated with a strong bottleneck effect. A specific analysis of the VP1 capsid gene of 15 human cases confirmed the high mutation incidence in this capsid region, but not in the antiviral drug-binding pocket. We could also estimate a mutation frequency in vivo of 3.4x10(-4 mutations/nucleotides and 3.1x10(-4 over the entire ORF and VP1 gene, respectively. In vivo, HRV generate new variants rapidly during the course of an acute infection due to mutations that accumulate in hot spot regions located at the capsid level, as well as in 2C and 3C genes.

  10. Comparative haematological changes in experimentally infected ...

    African Journals Online (AJOL)

    A comparative study of haematological changes in Savannah brown goats experimentally infected with Trypanosoma brucei and Trypanosoma vivax was carried out using thirty (30) goats aged between 20 and 48 months and average weight of 13.00 kg. The parameters determined before and after infection included ...

  11. 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, ...

  12. Show and tell: disclosure and data sharing in experimental pathology

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    Paul N. Schofield

    2016-06-01

    Full Text Available Reproducibility of data from experimental investigations using animal models is increasingly under scrutiny because of the potentially negative impact of poor reproducibility on the translation of basic research. Histopathology is a key tool in biomedical research, in particular for the phenotyping of animal models to provide insights into the pathobiology of diseases. Failure to disclose and share crucial histopathological experimental details compromises the validity of the review process and reliability of the conclusions. We discuss factors that affect the interpretation and validation of histopathology data in publications and the importance of making these data accessible to promote replicability in research.

  13. Parasitological and molecular diagnosis in experimental Strongyloides venezuelensis infection.

    Science.gov (United States)

    Paula, Fabiana Martins; Sitta, Renata Barnabé; Malta, Fernanda Mello; Gottardi, Maiara; Corral, Marcelo Andreetta; Gryschek, Ronaldo César Borges; Chieffi, Pedro Paulo

    2013-01-01

    Strongyloides venezuelensis is a parasitic nematode of rats which is frequently used as a model to study human and animal strongyloidiasis. The aim of this study was to evaluate the correlation between parasitological and molecular diagnosis in Strongyloides venezuelensis infection. PCR assays were used to detect S. venezuelensis DNA in fecal samples obtained from experimentally infected Rattus norvegicus. The results showed a higher sensitivity of the PCR assay in detecting the infection compared to parasitological methods.

  14. Protective effects of pidotimod against experimental bacterial infections in mice.

    Science.gov (United States)

    Coppi, G; Falcone, A; Manzardo, S

    1994-12-01

    Pidotimod ((R)-3-[(S)-(5-oxo-2-pyrrolidinyl) carbonyl]-thiazolidine-4-carboxylic acid, PGT/1A, CAS 121808-62-6) protected mice against experimental bacterial infections in different experimental models. In all tests the drug's effect was measured as protection from death. The activity of pidotimod was evident and statistically significant after 5 administrations before the bacterial challenges. Pidotimod was active against many bacterial species infections, its active dosages ranging from 0.01 to 100 mg/kg i.p. x 5 times. Pidotimod showed against some bacterial infections a protection similar or better than those of bestatin, N-acetylmuramyl-L-Ala-D-isoGlu-OH and tuftsin. It showed high protection against bacterial infections in cyclophosphamide-immunodepressed mice. Finally, pidotimod showed an additive or synergic activity in combination with beta-lactam antibiotics (cefotaxime, ampicillin) against bacterial infections in mice.

  15. An experimental Schistosoma mattheei infection in man.

    Science.gov (United States)

    Wolmarans, C T; de Kock, K N; van der Walt, M P

    1990-12-01

    Certain aspects of the immune response of a male experimentally infected with 3-day old cercariae of a pure field strain of Schistosoma matheei were investigated. Among others, aspects such as the reaction of eosinophils, neutrophils and blood platelets after infection, were included in the study. The involvement of IgG and the cross reaction between these antibodies and S. haematobium and S. mansoni were also investigated. The phenomenon that the cercariae were, 3 days after shedding, still capable of penetrating the skin causing an inflammatory response was studied. The results lend some support to the surmise that a pure S. mattheei infection in humans is incapable of any egg production.

  16. Experimental Proteus mirabilis Burn Surface Infection

    Science.gov (United States)

    1982-02-01

    mirabilis Burn Surface Infection Albert T. McManus, PhD; Charles G. McLeod, Jr, DVM; Arthur D. Mason, Jr, MD * We established a human burn Isolate of...William J1. Northam. Peter A. lDorsaneo, and Paulette langlinais MS. model may be useful in evaluation of experimental antibi - prov ided technical support

  17. 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...

  18. Experimental Ascaris suum infection in Yankasa lambs ...

    African Journals Online (AJOL)

    aliyu.jibril

    2017-04-11

    Apr 11, 2017 ... Experimental Ascaris suum infection in Yankasa lambs: Parasitological and pathological observations. I Isah. 1. *, JO Ajanusi. 1. , NP Chiezey. 2. , LB Tekdek. 3. & B Mohammed. 4. 1. Department of Veterinary Parasitology and Entomology, Faculty of Veterinary Medicine,. Ahmadu Bello University, Zaria, ...

  19. Experimental Campylobacter Jejuni Infection in Humans

    Science.gov (United States)

    1988-03-01

    Blaser MJI Black RE. Duncan DJ, Amer I. Campylobacter Clements ML, Robins-Brone R, Lim Y-L. Duration of jejuni -specific serum antibodies are elevated in...SUBTITLE 5 FUNDING •4UMBERS Experimental Campylobacter jejuni Infection 86PP6826 in Humans 61102A 30161102BS13 AB6. AUTHOR(S)DA328 Robert E. Black...SUPPLEMENTARY NOTES Contract Title: Studies of the Outer Membrane Proteins of Campylobacter Jejuni for Vaccine Development ൔa• DISTRIBUTION

  20. Nonlinear hierarchical modeling of experimental infection data.

    Science.gov (United States)

    Singleton, Michael D; Breheny, Patrick J

    2016-08-01

    In this paper, we propose a nonlinear hierarchical model (NLHM) for analyzing longitudinal experimental infection (EI) data. The NLHM offers several improvements over commonly used alternatives such as repeated measures analysis of variance (RM-ANOVA) and the linear mixed model (LMM). It enables comparison of relevant biological properties of the course of infection including peak intensity, duration and time to peak, rather than simply comparing mean responses at each observation time. We illustrate the practical benefits of this model and the insights it yields using data from experimental infection studies on equine arteritis virus. Finally, we demonstrate via simulation studies that the NLHM substantially reduces bias and improves the power to detect differences in relevant features of the infection response between two populations. For example, to detect a 20% difference in response duration between two groups (n=15) in which the peak time and peak intensity were identical, the RM-ANOVA test had a power of just 11%, and LMM a power of just 12%. By comparison, the nonlinear model we propose had a power of 58% in the same scenario, while controlling the Type I error rate better than the other two methods. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. CD36 deficiency attenuates experimental mycobacterial infection

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    Min-Oo Gundula

    2010-10-01

    Full Text Available Abstract Background Members of the CD36 scavenger receptor family have been implicated as sensors of microbial products that mediate phagocytosis and inflammation in response to a broad range of pathogens. We investigated the role of CD36 in host response to mycobacterial infection. Methods Experimental Mycobacterium bovis Bacillus Calmette-Guérin (BCG infection in Cd36+/+ and Cd36-/- mice, and in vitro co-cultivation of M. tuberculosis, BCG and M. marinum with Cd36+/+ and Cd36-/-murine macrophages. Results Using an in vivo model of BCG infection in Cd36+/+ and Cd36-/- mice, we found that mycobacterial burden in liver and spleen is reduced (83% lower peak splenic colony forming units, p Cd36-/- animals. Intracellular growth of all three mycobacterial species was reduced in Cd36-/- relative to wild type Cd36+/+ macrophages in vitro. This difference was not attributable to alterations in mycobacterial uptake, macrophage viability, rate of macrophage apoptosis, production of reactive oxygen and/or nitrogen species, TNF or interleukin-10. Using an in vitro model designed to recapitulate cellular events implicated in mycobacterial infection and dissemination in vivo (i.e., phagocytosis of apoptotic macrophages containing mycobacteria, we demonstrated reduced recovery of viable mycobacteria within Cd36-/- macrophages. Conclusions Together, these data indicate that CD36 deficiency confers resistance to mycobacterial infection. This observation is best explained by reduced intracellular survival of mycobacteria in the Cd36-/- macrophage and a role for CD36 in the cellular events involved in granuloma formation that promote early bacterial expansion and dissemination.

  2. Mono- and combined antimicrobial agents efficiency in experimental wound infection

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    Наталія Ігорівна Філімонова

    2015-10-01

    Full Text Available Modern problems of antibiotic therapy are shown by wide range of side effects, both on organism and microbiological levels: the spread of allergies, toxic for organ systems reactions, dysbiosis development, and resistant pathogens formation and dissemination. Therefore the necessity of search for new effective drugs with significant antimicrobial activity applied for the wounds treatment arises. Development of combined remedies on the background of different origin antimicrobial agents’ derivatives is one of the fight directions against infectious diseases in the skin pathology. Recently among the existing antimicrobial agents one should focus on antiseptic drugs, due to degenerative and dysfunctional effect on microbial cell.Aim of research. The comparison of mono- and combined antimicrobial agents chemotherapeutic efficiency in the treatment of localized purulent infection under experimental conditions.Metods. The study of chemotherapeutic efficiency was carried out on the model of localized purulent Staphylococcus infection on albino mice weighting 14 – 16 g. S.aureus ATCC 25923 strains were used as infectious agents. The contamination was performed subcutaneously to the right side of mice’s skin after depilation. The animals were randomly divided into 4 groups: the 1st group – infected mice without treatment (control; the 2nd group – infected mice treated with a ciprofloxacin; the 3rd group – infected mice treated with a Ciprofloxacin and Decamethoxin combination; the 4th group – infected mice treated with a combined drug on the base of mutual prodrugs (Hexamethylenetetramine and Phenyl salicylate.Results. The efficiency of mono- and combined antimicrobial agents under experimental Staphylococcus wound infection conditions was studied. It was found that localized purulent staph center was formed more slowly in comparison with control and mono preparation use (2nd group of animals. The average index of skin lesions in comparison

  3. Aortic Graft Infection: Graphene Shows the Way to an Infection-Resistant Vascular Graft

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    Nikolaos Patelis

    2017-05-01

    Full Text Available Aortic graft infection is a potentially lethal complication of open and endovascular repair of aortic aneurysms. Graphene is the only existing two-dimensional material, and its unique structure gives graphene and its derivatives a plethora of original characteristics. Among other characteristics, graphene demonstrates bacteriostatic and bactericidal effects that could potentially resolve the problem of graft infection in the future. Data already exist in literature supporting this antibacterial effect of graphene oxide and reduced graphene oxide. Combining these materials with other substances enhances the antibacterial effect. Additionally, it looks feasible to expect antibiotic-delivering graphene-based graft materials in the future. Based on already published data, we could conclude that regarding graphene and its derivatives, the blessing of bactericidal effect comes with the curse of human cells toxicity. Therefore, it is important to find a fine balance between the desired antibacterial and the adverse cytotoxic effect before graphene is used in graft materials for humans.

  4. The pathology observed in experimental Fasciola gigantica infected ...

    African Journals Online (AJOL)

    Pathological lesions were observed in four Fasciola gigantica infected Yankasa sheep that died at the 10th, 11th and 12th week post-infection in an experimental infection at the Reproduction unit of the National Animal production Research institute, Shika-Zaria, Nigeria. The experiment involved twelve Yankasa sheep that ...

  5. Metabolic phenotyping in the mouse model of urinary tract infection shows that 3-hydroxybutyrate in plasma is associated with infection.

    Directory of Open Access Journals (Sweden)

    Pei Han

    Full Text Available Urinary tract infection is one of the most common bacterial infections worldwide. Current diagnosis of urinary tract infection chiefly relies on its clinical presentation, urine dipstick tests and urine culture. Small molecules found in bio-fluids related with both infection and recovery would facilitate diagnosis and management of UTI. Mass spectrometry-based fingerprinting of plasma and urine at 3 time points, pre-infection (t = -24h, infection (t = 24h and post 3-day treatment (t = 112h, were acquired in the following four groups: mice which were healthy, infected but not treated, infected and treated with ciprofloxacin, and infected and treated with Relinqing® granules (n = 6 per group. A metabolomics workflow including multivariate analysis and ROC regression was employed to select metabolic features that correlated with UTI and its treatment. Circa 4,000 molecular features were acquired for each sample. The small acid 3-hydroxybutyrate in plasma was found to be differentiated for urinary tract infection, with an area under the curve = 0.97 (95% confidence interval: 0.93-1.00, accuracy = 0.91, sensitivity = 0.92 and specificity = 0.91. The level of 3-hydroxybutyrate in plasma was depleted after infection with a fold change of -22 (q < 0.0001. Correlation between plasma 3-hydroxybutyrate and urine bacterial number in all groups and time points was r = -0.753 (p < 0.0001. The findings show that 3-hydroxybutyrate is depleted in blood and strongly associated with UTI at both infection and post-treatment stage in a UTI mouse model. Further work is envisaged to assess the clinical potential of blood tests to assist with UTI management.

  6. Circulating levels of cyclooxygenase metabolites in experimental Trypanosoma cruzi infections

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    Rita L. Cardoni

    2004-01-01

    Full Text Available TRYPANOSOMA cruzi induces inflammatory reactions in several tissues. The production of prostaglandin F2α, 6-keto-prostaglandin F1α and thromboxane B2, known to regulate the immune response and to participate in inflammatory reactions, was studied in mice experimentally infected with T. cruzi. The generation of nitric oxide (NO, which could be regulated by cyclooxygenase metabolites, was also evaluated. In the acute infection the extension of inflammatory infiltrates in skeletal muscle as well as the circulating levels of cyclooxygenase metabolites and NO were higher in resistant C3H mice than in susceptible BALB/c mice. In addition, the spontaneous release of NO by spleen cells increased earlier in the C3H mouse strain. In the chronic infections, the tissue inflammatory reaction was still prominent in both groups of mice, but a moderate increase of thromboxane B2 concentration and in NO released by spleen cells was observed only in C3H mice. This comparative study shows that these mediators could be mainly related to protective mechanisms in the acute phase, but seem not to be involved in its maintenance in the chronic T. cruzi infections.

  7. Experimental Infections Of Domestic Rabbits ( Oryctolagus cuniculus ...

    African Journals Online (AJOL)

    Nigerian Journal of Animal Production ... Comparative study of single infections of domestic rabbits (Oryctolagus cuniculus) with Nigerian isolates of Trypanosoma brucei (Gboko strain), and Trypanosoma congolense (Binchi ... Eighteen rabbits of 10-14 weeks old weighing between 600-1200 grams were used for the study.

  8. Experimental Infection of Sheep using Infective Lar- vae (L3 ...

    African Journals Online (AJOL)

    Vet. J., 2014, 18 (2), 71-81 ther research is recommended to determine the impact of multiple-species habitat ... to be reservoir hosts of helminth infections than wild species (Cook et al., 1979;. Richardson and Demarias .... coincidentally there was also a positive relationship, Regression statistics. (R²=0.6696) between total ...

  9. Coronavirus Infections in the Central Nervous System and Respiratory Tract Show Distinct Features in Hospitalized Children.

    Science.gov (United States)

    Li, Yuanyuan; Li, Haipeng; Fan, Ruyan; Wen, Bo; Zhang, Jian; Cao, Xiaoying; Wang, Chengwu; Song, Zhanyi; Li, Shuochi; Li, Xiaojie; Lv, Xinjun; Qu, Xiaowang; Huang, Renbin; Liu, Wenpei

    2016-01-01

    Coronavirus (CoV) infections induce respiratory tract illnesses and central nervous system (CNS) diseases. We aimed to explore the cytokine expression profiles in hospitalized children with CoV-CNS and CoV-respiratory tract infections. A total of 183 and 236 hospitalized children with acute encephalitis-like syndrome and respiratory tract infection, respectively, were screened for anti-CoV IgM antibodies. The expression profiles of multiple cytokines were determined in CoV-positive patients. Anti-CoV IgM antibodies were detected in 22/183 (12.02%) and 26/236 (11.02%) patients with acute encephalitis-like syndrome and respiratory tract infection, respectively. Cytokine analysis revealed that the level of serum granulocyte colony-stimulating factor (G-CSF) was significantly higher in both CoV-CNS and CoV-respiratory tract infection compared with healthy controls. Additionally, the serum level of granulocyte macrophage colony-stimulating factor (GM-CSF) was significantly higher in CoV-CNS infection than in CoV-respiratory tract infection. In patients with CoV-CNS infection, the levels of IL-6, IL-8, MCP-1, and GM-CSF were significantly higher in their cerebrospinal fluid samples than in matched serum samples. To the best of our knowledge, this is the first report showing a high incidence of CoV infection in hospitalized children, especially with CNS illness. The characteristic cytokine expression profiles in CoV infection indicate the importance of host immune response in disease progression. © 2017 S. Karger AG, Basel.

  10. 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

  11. Changes in microbiota during experimental human Rhinovirus infection

    NARCIS (Netherlands)

    Hofstra, J. J.; Matamoros, S.; van de Pol, M. A.; de Wever, B.; Tanck, M. W.; Wendt-Knol, H.; Deijs, M.; van der Hoek, L.; Wolthers, K. C.; Molenkamp, R.; Visser, C. E.; Sterk, P. J.; Lutter, R.; de Jong, M. D.

    2015-01-01

    Human Rhinovirus (HRV) is responsible for the majority of common colds and is frequently accompanied by secondary bacterial infections through poorly understood mechanisms. We investigated the effects of experimental human HRV serotype 16 infection on the upper respiratory tract microbiota. Six

  12. Experimental rhinovirus infection in COPD: implications for antiviral therapies.

    Science.gov (United States)

    Gunawardana, Natasha; Finney, Lydia; Johnston, Sebastian L; Mallia, Patrick

    2014-02-01

    Chronic obstructive pulmonary disease (COPD) is a major public health problem and will be one of the leading global causes of mortality over the coming decades. Much of the morbidity, mortality and health care costs of COPD are attributable to acute exacerbations, the commonest causes of which are respiratory infections. Respiratory viruses are frequently detected in COPD exacerbations but direct proof of a causative relationship has been lacking. We have developed a model of COPD exacerbation using experimental rhinovirus infection in COPD patients and this has established a causative relationship between virus infection and exacerbations. In addition it has determined some of the molecular mechanisms linking virus infections to COPD exacerbations and identified potential new therapeutic targets. This new data should stimulate research into the role of antiviral agents as potential treatments for COPD exacerbations. Testing of antiviral agents has been hampered by the lack of a small animal model for rhinovirus infection and experimental rhinovirus infection in healthy volunteers has been used to test treatments for the common cold. Experimental rhinovirus infection in COPD subjects offers the prospect of a model that can be used to evaluate the effects of new treatments for virus-induced COPD exacerbations, and provide essential data that can be used in making decisions regarding large scale clinical trials. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Brazilian vaccinia virus strains show a classical orthopoxvirus in-fection course and cross-protection

    Institute of Scientific and Technical Information of China (English)

    Betania Paiva Drumond; Jonatas Santos Abraho; Zlia Ins Portela Lobato; Cludio Antonio Bonjardim; Paulo Csar Peregrino Ferreira; Erna Geessien Kroon

    2009-01-01

    Objectives:The purpose of this work was to study the infection course and cross-protection in mice after intra-dermal injection of Vaccinia virus (VACV ) strain Western Reserve and three Brazilian VACV strains:Araatuba,Muriaéand BeAn58058 isolated from cow,human and rodent,respectively.Methods:Balb /c mice were inoculated by footpad and back scarification and daily monitored regarding lesion development and weight loss.To check cross protection after intradermal VACV inoculation,mice were subsequently infected with different VACV strains and monitored to check lesion development.Serum neutralization assays were per-formed to check for the presence of antibodies against Orthopoxvirus.Results:After VACV intradermal inocu-lation the lesion development pattern was similar in mice infected with the different virus strains.By using the footpad scarification model,cross-protection among VACV strains was observed.Moreover,neutralizing anti-bodies against Orthopoxvirus were detected in sera from mice infected with all VACV strains.Conclusion:Al-though it was not possible to observe virulence differences among VACV strains isolated from cow,rodent and human using the murine model,this inoculation route showed to be an appropriated model to study lesions de-velopment since it mimics natural infections by VACV in nature.

  14. Experimental Infections of Wild Birds with West Nile Virus

    Directory of Open Access Journals (Sweden)

    Elisa Pérez-Ramírez

    2014-02-01

    Full Text Available Avian models of West Nile virus (WNV disease have become pivotal in the study of infection pathogenesis and transmission, despite the intrinsic constraints that represents this type of experimental research that needs to be conducted in biosecurity level 3 (BSL3 facilities. This review summarizes the main achievements of WNV experimental research carried out in wild birds, highlighting advantages and limitations of this model. Viral and host factors that determine the infection outcome are analyzed in detail, as well as recent discoveries about avian immunity, viral transmission, and persistence achieved through experimental research. Studies of laboratory infections in the natural host will help to understand variations in susceptibility and reservoir competence among bird species, as well as in the epidemiological patterns found in different affected areas.

  15. Experimental Infections of Wild Birds with West Nile Virus

    Science.gov (United States)

    Pérez-Ramírez, Elisa; Llorente, Francisco; Jiménez-Clavero, Miguel Ángel

    2014-01-01

    Avian models of West Nile virus (WNV) disease have become pivotal in the study of infection pathogenesis and transmission, despite the intrinsic constraints that represents this type of experimental research that needs to be conducted in biosecurity level 3 (BSL3) facilities. This review summarizes the main achievements of WNV experimental research carried out in wild birds, highlighting advantages and limitations of this model. Viral and host factors that determine the infection outcome are analyzed in detail, as well as recent discoveries about avian immunity, viral transmission, and persistence achieved through experimental research. Studies of laboratory infections in the natural host will help to understand variations in susceptibility and reservoir competence among bird species, as well as in the epidemiological patterns found in different affected areas. PMID:24531334

  16. Hepatitis E virus infection in farmed rabbits and swine in the Eastern Chinese city Lianyungang: showing no potential interspecies transmission.

    Science.gov (United States)

    Han, Jian; Zeng, Hang; Wang, Ling; Liu, Peng; Liu, Lin; Xia, Junke; Zhang, Yulin; Wang, Lin; Zhuang, Hui

    2014-11-01

    Rabbit HEV isolated recently from farmed rabbits in China has been shown experimentally to be able to infect both cynomolgus macaques and pigs. The purpose of the present study was to investigate the extent to which cross-species transmission of rabbit HEV in farm settings is a significant factor in the spread of this zoonotic infection. Rabbit and swine feces were collected from the same area in Eastern China (Lianyungang City) and analyzed by RT-PCR. Partial genome sequencing of a 365 bp region of ORF2 from the HEV positive rabbit samples revealed that they had 92-99% sequence identity with rabbit strains (rbIM163-c1 and rbIM004) isolated from Inner Mongolia. Similarly, sequencing of a 765 bp region of ORF2 of HEV positive swine samples showed 96-98% sequence identity with genotype 4d isolates collected from patients in the Yantai and Nanjing regions of China. By contrast, the sequence identity between the rabbit and swine isolates was only 73-75%, with no molecular biological evidence of interspecies transmission having occurred. It is concluded that whilst interspecies infection with rabbit HEV can be achieved experimentally, in the field it is not a significant factor in zoonotic disease transmission at least in the area of China where this study was undertaken. © 2014 Wiley Periodicals, Inc.

  17. Experimental Trypanosoma evansi infection in South American coati (Nasua nasua): hematological, biochemical and histopathological changes.

    Science.gov (United States)

    Herrera, H M; Alessi, A C; Marques, L C; Santana, A E; Aquino, L P C T; Menezes, R F; Moraes, M A V; Machado, R Z

    2002-03-01

    The course of an experimental Trypanosoma evansi infection in coatis (Nasua nasua, carnivora, Procyonidae) was followed for 262 days. Hematological analysis of the infected coatis revealed a marked decline in hemoglobin, packed-cell volume, and total erythrocyte count. An intense anemia followed the first wave of parasitemia and persisted until the end of the experimental period. Biochemical analysis showed increased serum levels of alanine aminotransferase and aspartate aminotransferase and decreased albumin. The main histopathological features consisted of myocarditis with the presence of degenerate cardiac fibers and meningoencephalitis. This study has shown that coatis infected with T. evansi develop a chronic disease.

  18. Analysis of experimental evidence that shows adverse effects of salt and its relation to hypertension

    Directory of Open Access Journals (Sweden)

    Ignacio Bravo A.

    2012-02-01

    Full Text Available The study by Taylor et al published in June 2010 in the American Journal of Hypertension questions the effectiveness of reducing salt intake in the diet in the prevention and treatment of high blood pressure and other cardiovascular conditions. The publication of this article has lead to great controversy and medical associations and learned societies responded promptly. The response criticized the results of the meta-analysis and pointed out its methodological shortcomings. In this review we critically appraise the experimental evidence that shows the importance of diet salt intake and its role as a determinant of blood pressure. We briefly describe the paradigm that explains the role of salt intake in contributing in the regulation of blood pressure (Guyton hypothesis and model and we mention the experimental evidence that supports this. We briefly comment on the classical studies that indicate that salt intake (NaCl contributes directly to the development of high blood pressure and target tissues. Finally, we briefly mention the experimental data that is related with the controversy on the role of salt (NaCl or sodium as prohypertensive agents.

  19. Study of the pathogenic potential of Dientamoeba fragilis in experimentally infected mice

    Directory of Open Access Journals (Sweden)

    Eman K. El-Gayar

    2016-06-01

    Full Text Available Dientamoebafragilis (D. fragilis is a protozoan parasite whose pathogenic potential is still disputable. The aim of this study was to illustrate the pathogenicity of D. fragilis infection and to determine the infective dose for experimental mice infection. Three groups of mice (8/each were orally inoculated with in vitro cultured D. fragilis. The infected groups (G1- G3 received 103, 105 and 4 × 106 D. fragilis/0.5 ml culture, respectively. A control group (G4 only received parasite-free culture. Two weeks post-inoculation all mice were euthanized for histopathological examination. All mice of G3 (100% and three mice of G2 (37.5% were infected, and the results were confirmed by PCR and different staining methods. On the other hand, all mice from group G1 showed a completely negative result. Histopathological examination of the colon and caecum of the highly infected group G3 showed active colitis, with infiltration of mixed inflammatory cells such as eosinophils, neutrophils and lymphocytes within the lamina propria of the intestinal wall. The parasite was not invading the colonic mucosa. This study revealed that infection with D. fragilis is dose-dependent. Moreover, a dose of 105 D. fragilis/mouse or higher is necessary to infect mice through the oral route. In addition, this route of infection, although non-invasive, can induce severe inflammatory changes to the colonic and caecal mucosa in experimentally infected mice.

  20. 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...

  1. 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.

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

    Science.gov (United States)

    Zhao, Tong-Mao; Hague, Bishop; Caudell, David L; Simpson, R Mark; Kindt, Thomas J

    2005-01-01

    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. PMID:15910683

  3. Experimental Theileria lestoquardi infection in sheep: Biochemical and hematological changes.

    Science.gov (United States)

    Yaghfoori, Saeed; Mohri, Mehrdad; Razmi, Gholamreza

    2017-09-01

    Malignant theileriosis (Theileria lestoquardi infection) is a hemoparasitic tick-borne disease that affects both wild and domestic small ruminants. The aim of this study was to evaluate biochemical and hematological characteristics of sheep after being experimentally infected by T. lestoquardi. T. lestoquardi infection was induced in seven Baluchi sheep of six-to-eight months old via experimentally-infected Hyalomma anatolicum adult ticks. Biochemical and hematological parameters were measured twice a week during the three weeks' post infection. Twenty-three biochemical analytes and seven hematological ones were measured. After three to four days infection, body temperature rose above 40(°)C. Maximum and minimum parasitaemia were 3.3% and 0.28%, respectively. Piroplasms and schizont were seen on average from days 7.2 and 4 post infection, respectively. The concentrations and activities of Alb, HDL, ALT, T3, T4, Ca, Fe, Mg, iP, WBC, RBC, PCV, Hb, Plt, neutrophil and lymphocytes significantly decreased (P≤0.05) during experimental infection. However, concentrations and activities of BT, GGT, Glu, BUN, Crea, FIB and Cu significantly increased (P≤0.05). There was no significant change in the serum amounts of Chol, LDL, TG, VLDL and Zn. The observed hypoalbuminemia and increase of FIB concentrations referred to pro-inflammatory cytokines production. Moreover, the raising of GGT activity indicates liver damage, cholestatic disorders or schizont infiltration. The disease stress and corticosteroids are suspected to cause the Glu concentration increase. The present study is aimed at improving the knowledge of malignant theileriosis. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Immunobiological characterization of Graphidium strigosum experimental infection in rabbits (Oryctolagus cuniculus).

    Science.gov (United States)

    Cuquerella, M; Alunda, J M

    2009-01-01

    An experimental infection of rabbits with a wild isolate of the gastric nematode Graphidium strigosum was carried out. Animals (3.5 months age) were infected with 1,000 L3 administered by bucoesophagic catheter (five rabbits) or kept as uninfected control group (five animals). The infection was maintained for 3 months. Along the experimental period, some parasitological, hematological and immunological parameters were determined. Prepatent period of the infection ranged from 30 to 38 days and, at necropsy, average adult helminth counts were 430.75 +/- 126.12. No significant variations were found in packed cell volume, leukocyte, and eosinophil counts along the experimental period. Infection elicited a clear serum-specific IgG response, estimated by ELISA, during patency. Pooled sera from the patent period of the infection recognized some soluble antigens, particularly, a 67-kDa protein. Experimentally infected animals did not show cross recognition between G. strigosum, Haemonchus contortus, and Teladorsagia circumcincta. However, Western blot analysis with hyperimmune sera against H. contortus raised in rabbits and lambs showed cross reactivity between this helminth species and G. strigosum.

  5. Nocardia brasiliensis: from microbe to human and experimental infections.

    Science.gov (United States)

    Salinas-Carmona, M C

    2000-09-01

    Nocardia brasiliensis is a Gram-positive bacterium that lives as a saprophyte in soil. In this article the physical properties, chemical composition and taxonomic position of this species is reviewed. Human infections and an experimental model of actinomycetoma in BALB/c mice as well as the host-immune response is described.

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

    African Journals Online (AJOL)

    The pathological effect of coccidiosis on sperm production of the male chickens had not been previously studied. It is note-worthy that coccidiosis infection in broiler males showed no degenerative changes in the seminiferous tubules and testis. In both cross and longitudinal sections of the testis of the infected male, there ...

  7. 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.

  8. Transcriptome Analysis of Enterococcus faecalis during Mammalian Infection Shows Cells Undergo Adaptation and Exist in a Stringent Response State

    Science.gov (United States)

    Frank, Kristi L.; Colomer-Winter, Cristina; Grindle, Suzanne M.; Lemos, José A.; Schlievert, Patrick M.; Dunny, Gary M.

    2014-01-01

    As both a commensal and a major cause of healthcare-associated infections in humans, Enterococcus faecalis is a remarkably adaptable organism. We investigated how E. faecalis adapts in a mammalian host as a pathogen by characterizing changes in the transcriptome during infection in a rabbit model of subdermal abscess formation using transcriptional microarrays. The microarray experiments detected 222 and 291 differentially regulated genes in E. faecalis OG1RF at two and eight hours after subdermal chamber inoculation, respectively. The profile of significantly regulated genes at two hours post-inoculation included genes involved in stress response, metabolism, nutrient acquisition, and cell surface components, suggesting genome-wide adaptation to growth in an altered environment. At eight hours post-inoculation, 88% of the differentially expressed genes were down-regulated and matched a transcriptional profile consistent with a (p)ppGpp-mediated stringent response. Subsequent subdermal abscess infections with E. faecalis mutants lacking the (p)ppGpp synthetase/hydrolase RSH, the small synthetase RelQ, or both enzymes, suggest that intracellular (p)ppGpp levels, but not stringent response activation, influence persistence in the model. The ability of cells to synthesize (p)ppGpp was also found to be important for growth in human serum and whole blood. The data presented in this report provide the first genome-wide insights on E. faecalis in vivo gene expression and regulation measured by transcriptional profiling during infection in a mammalian host and show that (p)ppGpp levels affect viability of E. faecalis in multiple conditions relevant to mammalian infection. The subdermal abscess model can serve as a novel experimental system for studying the E. faecalis stringent response in the context of the mammalian immune system. PMID:25545155

  9. Ocular pathological changes in hamsters experimentally infected with Schistosoma mansoni.

    Science.gov (United States)

    Ismail, H I H; Ashour, D S; Abou Rayia, D M; Ali, A L

    2016-11-01

    Ocular lesions have been reported in patients with schistosomiasis; however, the problem with studying schistosomal infection of the human eye is that biopsies are almost impossible to take, and histopathological examination of suspicious lesions can only be undertaken post-mortem or after enucleation. This work aimed to study the possible effects and pathogenesis of schistosomiasis on the eye. This study involved 55 hamsters; five hamsters remained non-infected and the remaining 50 hamsters were infected with Schistosoma mansoni cercariae. Infected hamsters were sacrificed on weeks 8, 12, 16 and 20 post-infection (pi). Eye sections were prepared and stained for histopathological and immunohistochemical studies. Histopathological changes detected in hamsters infected after 16 and 20 weeks included looseness and oedema of the innermost retinal layers together with hyperplastic polypoid growth. Neither eggs nor granulomata were detected in eye sections throughout the experimental period. Deposition of S. mansoni antigen was revealed in 35% of infected hamsters. Later, on weeks 16 and 20 pi, moderate subepithelial conjuctival deposits and marked subchoroidal and scleral deposition were detected. In conclusion, the deposition of schistosomal antigen and immune complexes may play a pivotal role in the ocular changes that occur in schistosomiasis, even in the absence of detectable Schistosoma eggs. Schistosomiasis should be suspected in cases with unexplained ophthalmological findings, especially in endemic areas.

  10. Immunopathological assessments of human Blastocystis spp. in experimentally infected immunocompetent and immunosuppresed mice.

    Science.gov (United States)

    Abdel-Hafeez, Ekhlas H; Ahmad, Azza K; Abdelgelil, Noha H; Abdellatif, Manal Z M; Kamal, Amany M; Hassanin, Kamel M A; Abdel-Razik, Abdel-Razik H; Abdel-Raheem, Ehab M

    2016-05-01

    Blastocystis spp., one of the most common parasites colonizing the human intestine, is an extracellular, luminal protozoan with controversial pathogenesis. The host's immune response against Blastocystis spp. infection has also not been defined yet. Therefore, this research aimed to assess the potential pathogenicity of this parasite and its ability to modulate the immune response in experimental infected immunocompetent and immunosuppresed mice. These results demonstrated that the infected immunosuppressed mice were more affected than infected immunocompetent mice. Histopathological examination of the small intestine in the infected immunosuppressed mice showed that Blastocystis spp. infiltrated all the layers. Moreover, the epithelia showed exfoliation and inflammatory cell infiltration in submucosa compared to that of the infected immunocompetent mice. As well, examination of the large intestine of the infected immunosuppressed group showed severe goblet cell hyperplasia. Blastocystis spp. infiltrated all the large intestine layers compared to that of the infected immunocompetent group. Furthermore, there was a significant upregulation of the expression of proinflammatory cytokines: interleukin 12 (IL-12) and tumor necrosis factor alpha (TNF-α) in the infected immunosuppressed mice compared to that of the infected immunocompetent ones (p ≤ 0.004 and p ≤ 0.002, respectively). However, the expression of anti-inflammatory cytokines (IL-4 and IL-10) was significantly downregulated in the infected immunosuppressed group compared to that of the infected immunocompetent group one at 10 days postinfection (p ≤ 0.002 and p ≤ 0.001, respectively). The results of this study revealed that Blastocystis spp. affected the production of pro- and anti-inflammatory cytokines in both groups of mice compared to healthy normal (naive) group. Additionally, these data showed that there was a significant upregulation (p ≤ 0.005) of the locally

  11. Glibenclamide, a Blocker of K+ATP Channels, Shows Antileishmanial Activity in Experimental Murine Cutaneous Leishmaniasis▿

    Science.gov (United States)

    Serrano-Martín, Xenón; Payares, Gilberto; Mendoza-León, Alexis

    2006-01-01

    Glibenclamide reduced the rate of lesion growth in BALB/c mice infected with Leishmania (Leishmania) mexicana, the effect was dose dependent, and the highest dose proved more effective than glucantime. Cross-resistance to glucantime was found in animals infected with a glibenclamide-resistant line, but combined therapy reduced lesion progression even in the glibenclamide-resistant strain. PMID:17015627

  12. Avian toxoplasmosis: experimental infection of chicken and pigeon.

    Science.gov (United States)

    Biancifiori, F; Rondini, C; Grelloni, V; Frescura, T

    1986-01-01

    Two groups of 13 new-laying hens each were infected by crop-route with 5000 and 50,000 infective oocysts of T. gondii. Four groups of 5 pigeons each were inoculated by crop-route with 50, 500, 1000 and 5000 infective oocysts. To each group of infected birds suitable controls were added. Hens from the experiment with 5000 infective oocysts were apparently resistant to the infection and they had no clinical signs in the succeeding 40 days p.i. Hens from the experiment with 50,000 infective oocysts showed an egg-drop and mortality in embryonated eggs, especially during the first 2 weeks p.i. Isolation of the parasite was unsuccessfully attempted from 720 embryonated eggs, produced by infected groups, and tested on various days p.i. and at different stages of infection. The parasite was isolated from the brain, heart, liver, spleen and lung of infected birds 7 and 15 days p.i.; 40 days p.i. it was evident only in brain and heart. IgG onset and mean course were monitored by ELISA and high titers were reached by both groups. Pigeons from groups 500, 1000 and 5000 developed rapidly progressive clinical signs as diarrhea, trembling, incoordination, torticollis and death. They had enlargement of liver and spleen and focal necrosis, nodular features in the crop. Pigeons from expt 50 had no clinical signs in spite of the presence of the parasite in their organs for over 45 days p.i. Parasite was isolated from brain, heart, liver, spleen, lung, kidney, crop and muscles from all infected groups. Histopathological and ultrastructural features revealed the presence of multiplying tachizoites even within cells of the crop. Seroconversion, as monitored by ELISA, was recorded in all infected groups although high ELISA-titres were never reached. One of the negative controls from expt 5000 developed specific antibodies but the parasite was not isolated from its organs.

  13. Pathogenicity of avian malaria in experimentally-infected Hawaii Amakihi

    Science.gov (United States)

    Atkinson, Carter T.; Dusek, Robert J.; Woods, K.L.; Iko, W.M.

    2000-01-01

    The introduction of avian malaria (Plasmodium relictum) and mosquitoes (Culex quinquefasciatus) to the Hawaiian Islands (USA) is believed to have played a major role in the decline and extinction of native Hawaiian honeycreepers (Drepanidinae). This introduced disease is thought to be one of the primary factors limiting recovery of honeycreepers at elevations below 1,200 m where native forest habitats are still relatively intact. One of the few remaining species of honeycreepers with a wide elevational distribution is the Hawaii Amakihi (Hernignathus virens). We measured morbidity and mortality in experimentally-infected Hawaii Amakihi that were captured in a high elevation, xeric habitat that is above the current range of the mosquito vector. Mortality among amakihi exposed to a single infective mosquito bite was 65% (13/20). All infected birds had significant declines in food consumption and a corresponding loss in body weight over the 60 day course of the experiment. Gross and microscopic lesions in birds that succumbed to malaria included enlargement and discoloration of the spleen and liver and parasitemias as high as 50% of circulating erythrocytes. Mortality in experimentally-infected amakihi was similar to that observed in Apapane (Himnatione sanguinea) and lower than that observed in Iiwi (Vestiaria coccinea) infected under similar conditions with the same parasite isolate. We conclude that the current elevational and geographic distribution of Hawaiian honeycreepers is determined by relative susceptibility to avian malaria.

  14. Dirofilaria immitis and D. repens show circadian co-periodicity in naturally co-infected dogs.

    Science.gov (United States)

    Ionică, Angela Monica; Matei, Ioana Adriana; D'Amico, Gianluca; Bel, Lucia Victoria; Dumitrache, Mirabela Oana; Modrý, David; Mihalca, Andrei Daniel

    2017-02-28

    Dirofilaria immitis and Dirofilaria repens are mosquito-borne zoonotic filarioids typically infecting dogs, causing a potentially fatal cardiopulmonary disease and dermatological conditions, respectively. The females are larviparous, releasing the larvae (microfilariae) into the bloodstream, which further develop in mosquito vectors. However, microfilaremia greatly fluctuates during a 24-h period. As the sampling time can greatly influence the accuracy of diagnosis, the aim of the present study was to assess the circadian periodicity of D. immitis and D. repens in naturally co-infected dogs in an endemic area of Romania and to investigate possible differences of periodicity between these two species. Overall, four dogs harbouring natural co-infection with D. immitis and D. repens were selected and sampled every two hours for two consecutive days: two dogs in July 2014 and two in July 2015. At each sampling time, a 0.7 ml blood sample was taken. Modified Knott's test was performed on 0.5 ml, and the remaining 0.2 ml were used for DNA extraction and molecular amplification, both in single and duplex PCR reactions. Microfilariae of both species were morphologically identified and counted in each collected sample, microfilaremia was calculated, and fluctuation was charted. The dynamics of microfilaremia showed similar patterns for both Dirofilaria species. In all four dogs, D. immitis was present at all sampling times, with several peak values of microfilaremia, of which one was common for all dogs (1 am), while minimum counts occurred between 5 and 9 am. Similarly, for D. repens, one of the peak values was recorded in all dogs at 1 am, while minimum counts (including zero) occurred at 9 and 11 am. Single species-specific PCR reactions were positive for both D. immitis and D. repens in all collected samples, while duplex PCR failed to amplify D. repens DNA in many cases. Both Dirofilaria immitis and D. repens microfilariae are subperiodic, following a similar

  15. 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.

  16. Experimental model for Porphyromonas gingivalis infection in animals.

    Science.gov (United States)

    Eke, P I; Rotimi, V O; Laughon, B E

    1996-03-01

    A virulence model suitable for studying the dynamics of Porphyromonas gingivalis infection, including the pathogenicity of P. gingivalis in experimentally induced infections of multiple organs was developed using mouse and hamster. Virulence of P. gingivalis strains was expressed contrastingly in subcutaneous (sc) infection in the Murine abscess model (MAM) and the Hamsters abscess model (HAM). Subcutaneous infection in the MAM was characterized by a gravity abscess, spreading from the primary site of inoculation downwards, frequently erupting as a secondary lesion. In contract, s.c. P. gingivalis infection in HAM was characterized as a palpable localized abscess at the primary site of inoculation. When the Semi-Solid Agar (SSA) was added to the mono-culture of P. gingivalis, reproducibility of infection in both models was enhanced. P. gingivalis culture supplemented with haemin, or combined with oral Actinomyces viscosus had its virulence overtly enhanced and often fatal in the MAM. Menadione, Eh reducing agents and mixture with the Streptococcus or A. neaslundii did not potentiate virulence in either mode. Transtracheal challenge of the lungs of hamster with P. gingivalis initiated an early pneumonitis and later sequelae of necrosis and abscess formation. Also, abscess was induced by direct inoculation of P. gingivalis in the muscles, liver and testes, but did not induce intra-abdominal abscesses. In conclusion, the HAM applied with the SSA procedure caused a localized P. gingivalis tissue infection with practical advantages for quantitative and qualitative studies of P. gingivalis infections. This study also demonstrates the pathogenic potential of P. gingivalis by reproducing similar infections in multiple anatomical sites.

  17. Haematological changes in Nile tilapia experimentally infected with Enterococcus sp.

    Directory of Open Access Journals (Sweden)

    ML. Martins

    Full Text Available This study evaluated the haematological changes in Nile tilapia experimentally infected with 1 x 10³ and 1 x 10(6 colony-forming units (CFU/mL of Enterococcus sp. in the swim bladder. The experiment consisted of four treatments in triplicates: non-injected fish (NI; fish injected with 1 mL of sterile saline solution 0.65% (SAL; fish injected with 1 x 10³ and 1 x 10(6 CFU/mL of Enterococcus diluted in 1 mL sterile saline. Twenty-four hours after injection, the fish were anesthetized and the blood collected. The haematological tests included red blood cell (RBC and white blood cell (WBC counts, hematocrit, number of total thrombocytes, and differential counting of WBC. Fish injected with 1 x 10(6 CFU/mL of Enterococcus showed a higher number of thrombocytes than the other treatments. White blood cell and lymphocyte numbers increased significantly in fish injected with 1 x 10(6 CFU/mL of Enterococcus when compared to non-injected control. There was significant increase in the number of neutrophils in saline injected fish and reduced number of monocytes after injections with 1 x 10(6 CFU/mL of Enterococcus. Hematocrit increased in fish injected with 1 x 10³ and 1 x 10(6 CFU/mL of Enterococcus.

  18. Experimental Babesia gibsoni infection in coyotes (Canis latrans).

    Science.gov (United States)

    Evers, Holly V; Kocan, A Alan; Reichard, Mason V; Meinkoth, James H

    2003-10-01

    Four 5 mo old captive raised coyotes (Canis latrans) were experimentally inoculated with approximately 1 x 10(6) Babesia gibsoni organisms. Parasites were detected 1 wk post-inoculation in all coyotes with maximum parasitemia of 8-11% occurring at 34 wk. Parasitemias remained at or above 1% for at least 12 wk and were still detectable 20 wk post-inoculation. All experimentally infected coyotes developed pale mucous membranes, splenomegaly, and a positive heme reaction in urine while one coyote exhibited mild depression and inappetence. Infected coyotes also developed a regenerative anemia, thrombocytopenia, and neutropenia. The mild clinical signs coupled with the high level and long duration of parasitemia indicate that coyotes could serve as reservoirs for B. gibsoni. Entrance of this foreign parasite into the United States suggests the need for strict quarantines and thorough health and blood film examinations for imported animals.

  19. Experimental data showing the thermal behavior of a flat roof with phase change material.

    Science.gov (United States)

    Tokuç, Ayça; Başaran, Tahsin; Yesügey, S Cengiz

    2015-12-01

    The selection and configuration of building materials for optimal energy efficiency in a building require some assumptions and models for the thermal behavior of the utilized materials. Although the models for many materials can be considered acceptable for simulation and calculation purposes, the work for modeling the real time behavior of phase change materials is still under development. The data given in this article shows the thermal behavior of a flat roof element with a phase change material (PCM) layer. The temperature and energy given to and taken from the building element are reported. In addition the solid-liquid behavior of the PCM is tracked through images. The resulting thermal behavior of the phase change material is discussed and simulated in [1] A. Tokuç, T. Başaran, S.C. Yesügey, An experimental and numerical investigation on the use of phase change materials in building elements: the case of a flat roof in Istanbul, Build. Energy, vol. 102, 2015, pp. 91-104.

  20. Experimental data showing the thermal behavior of a flat roof with phase change material

    Directory of Open Access Journals (Sweden)

    Ayça Tokuç

    2015-12-01

    Full Text Available The selection and configuration of building materials for optimal energy efficiency in a building require some assumptions and models for the thermal behavior of the utilized materials. Although the models for many materials can be considered acceptable for simulation and calculation purposes, the work for modeling the real time behavior of phase change materials is still under development. The data given in this article shows the thermal behavior of a flat roof element with a phase change material (PCM layer. The temperature and energy given to and taken from the building element are reported. In addition the solid–liquid behavior of the PCM is tracked through images. The resulting thermal behavior of the phase change material is discussed and simulated in [1] A. Tokuç, T. Başaran, S.C. Yesügey, An experimental and numerical investigation on the use of phase change materials in building elements: the case of a flat roof in Istanbul, Build. Energy, vol. 102, 2015, pp. 91–104.

  1. Gastritis induced by Helicobacter pylori infection in experimental rats.

    Science.gov (United States)

    Elseweidy, Mohamed M; Taha, Mona M; Younis, Nahla N; Ibrahim, Khadiga S; Hamouda, Hamdi A; Eldosouky, Mohamed A; Soliman, Hala

    2010-10-01

    Gastritis, an inflammation of gastric mucosa, may be due to many pathological factors and infection, such as with Helicobacter pylori. The use of experimental models of gastritis is important to evaluate the biochemical changes and study chemotherapeutic intervention. In a previous study we demonstrated an acute gastritis model induced by iodoacetamide. Our objective in this study was to evaluate a new gastritis model induced by H. pylori infection in experimental rats in terms of certain biomarkers in serum and mucosal tissues in addition to histopathological examination. Gastritis was induced in 20 albino Wistar rats by H. pylori isolated from antral biopsy taken from a 49-year-old male patient endoscopically diagnosed as having H. pylori infection. Another ten rats were used as controls. Serum gastrin, pepsinogen I activity, interleukin-6 (IL-6) and gastric mucosal myeloperoxidase (MPO) activity and prostaglandin E(2) (PGE(2)) were measured. Immunostaining for inducible nitric oxide synthase (iNOS), nitrotyrosine and DNA fragmentation were used to further evaluate H. pylori-induced gastritis. Serum gastrin, IL-6, mucosal MPO activity, and PGE(2) demonstrated significant increases joined with a decreased serum pepsinogen I activity (P gastritis models demonstrated massive oxidative stress and pronounced injury in mucosal tissue. Since our model in rats reflected the clinical picture of H. pylori infection, it can be considered as a consistent model to study chemotherapeutic intervention for this type of gastritis.

  2. RGMA and IL21R show association with experimental inflammation and multiple sclerosis

    DEFF Research Database (Denmark)

    Nohra, R; Beyeen, A D; Guo, J P

    2010-01-01

    Rat chromosome 1 harbors overlapping quantitative trait loci (QTL) for cytokine production and experimental models of inflammatory diseases. We fine-dissected this region that regulated cytokine production, myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyeliti...... biomarkers and therapeutic targets....

  3. Natural and experimental oral infection of nonhuman primates by bovine spongiform encephalopathy agents.

    Science.gov (United States)

    Bons, N; Mestre-Frances, N; Belli, P; Cathala, F; Gajdusek, D C; Brown, P

    1999-03-30

    Experimental lemurs either were infected orally with the agent of bovine spongiform encephalopathy (BSE) or were maintained as uninfected control animals. Immunohistochemical examination for proteinase-resistant protein (prion protein or PrP) was performed on tissues from two infected but still asymptomatic lemurs, killed 5 months after infection, and from three uninfected control lemurs. Control tissues showed no staining, whereas PrP was detected in the infected animals in tonsil, gastrointestinal tract and associated lymphatic tissues, and spleen. In addition, PrP was detected in ventral and dorsal roots of the cervical spinal cord, and within the spinal cord PrP could be traced in nerve tracts as far as the cerebral cortex. Similar patterns of PrP immunoreactivity were seen in two symptomatic and 18 apparently healthy lemurs in three different French primate centers, all of which had been fed diets supplemented with a beef protein product manufactured by a British company that has since ceased to include beef in its veterinary nutritional products. This study of BSE-infected lemurs early in their incubation period extends previous pathogenesis studies of the distribution of infectivity and PrP in natural and experimental scrapie. The similarity of neuropathology and PrP immunostaining patterns in experimentally infected animals to those observed in both symptomatic and asymptomatic animals in primate centers suggests that BSE contamination of zoo animals may have been more widespread than is generally appreciated.

  4. 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.

  5. Comparison of detection methods for Toxoplasma gondii in naturally and experimentally infected swine.

    Science.gov (United States)

    Hill, Dolores E; Chirukandoth, Sreekumar; Dubey, J P; Lunney, Joan K; Gamble, H Ray

    2006-10-10

    Results from recent serological surveys and epidemiological studies show that pigs raised in a variety of management systems can be carriers of the tissue cyst stage of Toxoplasma gondi. This parasite can be transmitted to humans through the consumption of improperly prepared pork, making detection and removal of infected swine carcasses from the food chain an important food safety issue. Several methods are available for detection of T. gondii infected swine, including serological assays, polymerase chain reaction, and animal bioassays. The aim of the present study was to compare the detection sensitivities of six of these commonly used methods for detection of T. gondii infection in tissues from naturally and experimentally infected pigs. The results indicate that a serum-based ELISA is the most sensitive method, of those tested, for detection of T. gondii infected swine.

  6. Effects of praziquantel on experimental Schistosoma bovis infection in goats.

    Science.gov (United States)

    Johansen, M V; Monrad, J; Christensen, N O

    1996-03-01

    The effect of praziquantel against experimental Schistosoma bovis infection in West African Dwarf goats was investigated. Thirty goats were exposed to 2000 cercariae each and 15 of those received a praziquantel treatment (60 mg kg-1) 13 weeks post-infection. One day, 1 week and 4 weeks post-treatment representative goats from each group were killed and worms were recovered by perfusion. For comparison, parasite-free control animals were monitored, some of which were given praziquantel. Every second week during the study, faecal samples were collected. The cure rate was 100% 1 day, 99.4% 1 week and 95.7% 4 weeks post-treatment. Tissue egg counts were significantly reduced (P < 0.001) 4 weeks post-treatment in all parts of the intestines, but not in the liver. Faecal egg counts were reduced by 84.1% 1 week and by 98.3% 3 weeks after treatment, the reduction being highly significant both 1 week 3 weeks after treatment (P < 0.001). Overall strong correlations between the number of worm pairs, tissue egg counts and the final faecal egg count were observed, indicating that the faecal egg counts during infection and following treatment can be used as a guideline for the pathology associated with the infection.

  7. Experimental rhinovirus infection in human volunteers exposed to ozone

    Energy Technology Data Exchange (ETDEWEB)

    Henderson, F.W.; Dubovi, E.J.; Harder, S.; Seal, E. Jr.; Graham, D.

    1988-05-01

    We studied 24 young adult male volunteers experimentally inoculated with type 39 rhinovirus to determine whether the course of viral infection was modified by exposure to moderate levels of ozone (0.3 ppm for 6 h per day) over the 5 days after virus inoculation. No differences in rhinovirus titers in nasal secretions, recruitment of neutrophils into nasal secretions, levels of interferon in nasal lavage fluid, in vitro lymphocyte proliferative responses to rhinovirus antigen, or levels of convalescent serum neutralizing antibody to type 39 rhinovirus were demonstrated in relation to ozone exposure. The level and pattern of ozone exposure used in this experiment had no demonstrable adverse effects on the immune responses necessary to limit and terminate rhinovirus infection of the upper respiratory tract.

  8. Experimental rhinovirus infection in human volunteers exposed to ozone.

    Science.gov (United States)

    Henderson, F W; Dubovi, E J; Harder, S; Seal, E; Graham, D

    1988-05-01

    We studied 24 young adult male volunteers experimentally inoculated with type 39 rhinovirus to determine whether the course of viral infection was modified by exposure to moderate levels of ozone (0.3 ppm for 6 h per day) over the 5 days after virus inoculation. No differences in rhinovirus titers in nasal secretions, recruitment of neutrophils into nasal secretions, levels of interferon in nasal lavage fluid, in vitro lymphocyte proliferative responses to rhinovirus antigen, or levels of convalescent serum neutralizing antibody to type 39 rhinovirus were demonstrated in relation to ozone exposure. The level and pattern of ozone exposure used in this experiment had no demonstrable adverse effects on the immune responses necessary to limit and terminate rhinovirus infection of the upper respiratory tract.

  9. Perception of iron deficiency from oral mucosa alterations that show a high prevalence of Candida infection.

    Science.gov (United States)

    Lu, Shin-Yu

    2016-08-01

    Iron deficiency (ID) is the most common cause of anemia. The aim of this study was to investigate patients with oral mucosa alterations as the initial manifestation of ID or ID anemia (IDA). Sixty-four patients (50 IDA and 14 ID) with a wide range of sore mouth were diagnosed and treated. The oral and physical manifestations as well as iron studies and anemia classification based on the mean and heterogeneity of red cell size were assessed. ID predisposed 64 patients to a high incidence of Candida infection (85%) and showed a variety of oral manifestations including angular cheilitis (63%), atrophic glossitis (AG; 59%), pseudomembranous candidosis (44%), erythematous candidosis (41%), median rhomboid glossitis (5%), chronic mucocutaneous candidosis (5%), papillary hyperplastic candidosis (3%), and cheilocandidosis (3%). Others included pale oral mucosa (31%), burning mouth (28%), and recurrent oral ulcers (6%). Colorectal cancers in two patients were diagnosed. The values of hemoglobin (Hb) in 64 ID patients varied from normal to life-threatening levels, but none had developed advanced systemic symptoms except fatigue. All had low serum iron and ferritin. Sixty (94%) patients had transferrin saturation oral mucosa alterations accompanying oral candidosis are a sensitive indicator of ID. All oral changes can be successfully ameliorated by iron therapy plus antifungals when candidosis exists. Investigating the origin of IDA is necessary, because it may be the first sign of a more serious disease, particularly malignancy. Copyright © 2016. Published by Elsevier B.V.

  10. 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.

  11. Experimental infection of dogs with Leishmania and saliva as a model to study Canine Visceral Leishmaniasis.

    Directory of Open Access Journals (Sweden)

    Dirceu Joaquim Costa

    Full Text Available BACKGROUND: Canine Visceral Leishmaniasis (CVL is a zoonotic disease caused by Leishmania infantum, transmitted by the bite of Lutzomyia longipalpis sand flies. Dogs are the main domestic reservoir of the parasite. The establishment of an experimental model that partially reproduces natural infection in dogs is very important to test vaccine candidates, mainly regarding those that use salivary proteins from the vector and new therapeutical approaches. METHODOLOGY/PRINCIPAL FINDINGS: In this report, we describe an experimental infection in dogs, using intradermal injection of Leishmania infantum plus salivary gland homogenate (SGH of Lutzomyia longipalpis. Thirty-five dogs were infected with 1×10(7 parasites combined with five pairs of Lutzomyia longipalpis salivary glands and followed for 450 days after infection and clinical, immunological and parasitological parameters were evaluated. Two hundred and ten days after infection we observed that 31,4% of dogs did not display detectable levels of anti-Leishmania antibodies but all presented different numbers of parasites in the lymph nodes. Animals with a positive xenodiagnosis had at least 3,35×10(5 parasites in their lymph nodes. An increase of IFN-γ and IL-10 levels was detected during infection. Twenty two percent of dogs developed symptoms of CVL during infection. CONCLUSION: The infection model described here shows some degree of similarity when compared with naturally infected dogs opening new perspectives for the study of CVL using an experimental model that employs the combination of parasites and sand fly saliva both present during natural transmission.

  12. Histopathological changes in sheep experimentally infected with Babesia ovis.

    Science.gov (United States)

    Habela, M A; Reina, D; Navarrete, I; Redondo, E; Hernández, S

    1991-01-01

    Histopathological study was made of 12 Merino sheep - five splenectomized and seven intact - experimentally infected with Babesia ovis. Non-purulent encephalitis; initially exudative and subsequently interstitial pneumonia; pericarditis, myocarditis and haemorrhagic endocarditis; centrilobular necrotic hepatitis; hyperplasia of the lymphoreticular system; necrosis and vascular changes in adrenal glands were observed. The kidney was the most severely affected organ, exhibiting acute tubular necrosis typical of kidney shock syndrome. The lesions observed were suggestive of hypovolemic shock culminating in haemorrhagic diathesis owing to consumptive coagulopathy. Additionally, the massive release of catabolites from lysis and necrosis apparently produced endotoxic shock.

  13. Dynamic distribution and tissue tropism of classical swine fever virus in experimentally infected pigs

    Science.gov (United States)

    2011-01-01

    Background Classical swine fever (CSF), caused by the Classical swine fever virus (CSFV), is an Office International des Epizooties (OIE) notifiable disease. However, we are far from fully understand the distribution, tissue tropism, pathogenesis, replication and excretion of CSFV in pigs. In this report, we investigated the dynamic distribution and tissue tropism of the virus in internal organs of the experimentally infected pigs using real-time RT-PCR and immunohistochemistry (IHC). Results A relative quantification real-time PCR was established and used to detect the virus load in internal organs of the experimentally infected pigs. The study revealed that the virus was detected in all 21 of the internal organs and blood collected from pigs at day 1 to day 8 post infections, and had an increasing virus load from day 1 to day 8 post infections. However, there was irregular distribution virus load in most internal organs over the first 2 days post infection. Blood, lymphoid tissue, pancreas and ileum usually contain the highest viral loads, while heart, duodenum and brain show relatively low viral loads. Conclusions All the data suggest that CSFV had an increasing virus load from day 1 to day 8 post infections in experimentally infected pigs detected by real-time RT-PCR, which was in consistent with the result of the IHC staining. The data also show that CSFV was likely to reproduce in blood, lymphoid tissue, pancreas and the ileum, while unlikely to replicate in the heart, duodenum and brain. The results provide a foundation for further clarification of the pathogenic mechanism of CSFV in internal organs, and indicate that blood, lymphoid tissue, pancreas and ileum may be preferred sites of acute infection. PMID:21535885

  14. 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.

  15. The Pathology of Experimental Rhoodococcus equi infection in foals

    Directory of Open Access Journals (Sweden)

    Karima Al-Salihi

    2013-03-01

    Full Text Available The pathology of experimental Rhodococcus equi (R. equi infection in 2-8 weeks-old-foal is studied. For this purpose, twenty foals were divided into three groups, and given R. equi intratracheally (1st group, through gastric route (2nd group and through umbilicus by contamination (3rd group. A control group of foals were given a Phosphate buffered Saline (PBS. Pulmonary and intestinal lesions were seen in foals of all infected groups. Grossly, there were multiple, variable-sized abscesses diffusely scattered throughout the lung parenchyma, in addition to the presence of different stages of pneumonia with variable-sized areas of consolidation and emphysema. Intestinal lesions were evident as engorgement of mesenteric blood vessels, subserosal hemorrhages seen along the intestinal tract especially the small intestine, in addition to enlargement of lymph nodes (mesenteric, bronchial and mediastinal. Some lymph nodes were edematous, have circular foci of caseous necrosis and some of them were filled with yellowish, thick creamy pus. The microscopic lesions were basically similar in all foals of the experimental groups, but varied depending on the time of death or euthanasia and included: acute pulmonary congestion, acute suppurative broncho-pneumonia, chronic pyogranulomatous pneumonia, and emphysematous and atelectatic area. There were focal necrosis of the pulmonary parenchyma and numerous bacterial colonies seen free or as aggregates within the cytoplasm of many histiocytes. Also, there were focal interstitial thickening of the alveolar septae. The pleura and interlobular septae were thickened due to cellular infiltration.

  16. Efficacy of toltrazuril against experimental infections with Eimeria labbeana and E. columbarum in racing pigeons.

    Science.gov (United States)

    Van Reeth, K; Vercruysse, J

    1993-01-01

    The efficacy of toltrazuril against heavy experimental Eimeria labbeana and E. columbarum infections in racing pigeons was investigated. Pigeons were treated with toltrazuril at a dose of 20 mg/kg body weight before, during, and after the pre-patent period. In pigeons treated during pre-patency (1-5 days postinoculation [PI]), a 99.9% reduction in oocyst output was observed at day 7 PI. Treatment during patency (6-7 days PI) resulted in an interruption of oocyst shedding within 3 to 4 days. Pigeons treated with toltrazuril up to 14 days before the experimental infection showed on average a reduction of more than 97% in the number of oocysts in individual fecal samples. Finally, at reinfection, the immune response of pigeons previously treated during pre-patency was not altered compared with the response of infected unmedicated controls.

  17. Diurnal fluctuations in nematode egg excretion in naturally and in experimentally infected chickens.

    Science.gov (United States)

    Wongrak, Kalyakorn; Gauly, Matthias; Daş, Gürbüz

    2015-03-15

    We investigated whether nematode egg excretion through feces of naturally or experimentally infected chickens follow certain patterns within a day, which may allow determining the most appropriate sampling time for the highest parasite egg concentration. Feces samples (n=864) from chickens (n=36) with naturally occurring mixed nematode infections (trials N1, N2) or with an experimental Ascaridia galli infection (E) were collected quantitatively every 4h for four consecutive days. Number of eggs per gram of feces (EPG) was determined, and accumulative egg output (AEO) at each sampling time as well as total number of eggs excreted within 24h (eggs per day, EPD) were then estimated. At the end of the collection period, the hens were necropsied and their worm burdens determined. Naturally infected hens harbored Heterakis gallinarum (100%), Capillaria spp. (95.7%) and A. galli (91.3%). The experimental A. galli infection produced patent infections in all the birds. In general, both fecal egg concentration (EPG) and the amount of feces increased (P0.05) between effects of sampling hours and days on EPG and AEO, suggesting the existence of repeatable diurnal fluctuations within each day. Although an association between climatic parameters (e.g., ambient temperature and relative humidity) and the nematode egg excretion was quantified, a causal relationship could not be demonstrated. We conclude that nematode egg excretion through chicken feces in both natural and experimental infections shows repeatable diurnal fluctuations, which may indicate adaptive strategies by nematodes and eventually favor parasite spread. Since analytic sensitivity of fecal egg counts suffers from low egg concentrations in feces, samples taken during the daytime have a higher diagnostic value. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Neospora caninum infection in birds: experimental infections in chicken and embryonated eggs.

    Science.gov (United States)

    Furuta, P I; Mineo, T W P; Carrasco, A O T; Godoy, G S; Pinto, A A; Machado, R Z

    2007-12-01

    Neospora caninum causes economical impact in cattle-raising farms since it is implicated as the major cause of bovine abortions. Although infection by the parasite has been widely described in mammals, the role of birds in its life-cycle is still obscure. Therefore, this work aimed to evaluate the infection by N. caninum in different chicken models. Experimental infections were conducted in 7-day-old chicks, laying hens and embryonated eggs, where samples were analysed for parasite burden, IgG antibodies and lesions promoted. Chickens demonstrated an asymptomatic infection, although with seroconversion and systemic replication of the parasite. In laying hens, no signs of vertical transmission were observed. However, embryonated eggs inoculated by the allantoic cavity route demonstrated susceptibility to infection, with mortality rates around 50% independent of the inoculum dose. Additionally, dogs became infected after ingestion of different amounts of inoculated eggs, producing either oocysts or specific IgG antibodies. The results herein presented demonstrate that chickens may be intermediate hosts of N. caninum and that embryonated eggs could be a useful model to study the parasite's biology.

  19. 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

  20. Inferring biomarkers for Mycobacterium avium subsp. paratuberculosis infection and disease progression in cattle using experimental data

    Science.gov (United States)

    Magombedze, Gesham; Shiri, Tinevimbo; Eda, Shigetoshi; Stabel, Judy R.

    2017-03-01

    Available diagnostic assays for Mycobacterium avium subsp. paratuberculosis (MAP) have poor sensitivities and cannot detect early stages of infection, therefore, there is need to find new diagnostic markers for early infection detection and disease stages. We analyzed longitudinal IFN-γ, ELISA-antibody and fecal shedding experimental sensitivity scores for MAP infection detection and disease progression. We used both statistical methods and dynamic mathematical models to (i) evaluate the empirical assays (ii) infer and explain biological mechanisms that affect the time evolution of the biomarkers, and (iii) predict disease stages of 57 animals that were naturally infected with MAP. This analysis confirms that the fecal test is the best marker for disease progression and illustrates that Th1/Th2 (IFN-γ/ELISA antibodies) assays are important for infection detection, but cannot reliably predict persistent infections. Our results show that the theoretical simulated macrophage-based assay is a potential good diagnostic marker for MAP persistent infections and predictor of disease specific stages. We therefore recommend specifically designed experiments to test the use of a based assay in the diagnosis of MAP infections.

  1. Experimental inoculation of calves with atypical Hobi-like pestivirus shows pattern similar to BVDV-1

    DEFF Research Database (Denmark)

    Larska, Magdalena; Polak, Mirosław P.; Uttenthal, Åse

    of experimental inoculation of European cattle with atypical pestivirus. The experiment included 4 groups of 5 calves each inoculated with: BVDV-1 (Ho916), Hobi-like pestivirus (Th/04_KhonKaen), a mixture of both viruses or EaglesMEM (control animals). Th/04_KhonKaen induced milder clinical signs than observed......Newly emerging pestiviruses, detected first as containment of cell culture fluids originated from Brazil and named Hobi-like are becoming a concern for diagnostic labs, vaccine producers and for BVDV control and eradication programs. The epidemiology of the virus is not known, however recent...... has shown that Hobi-like viruses share similar to BVDV-1clinical pattern inducing rather subclinical disease with apparent immunosuppression of the host....

  2. 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.

  3. Pathology of Experimental Encephalitozoon cuniculi Infection in Immunocompetent and Immunosuppressed Mice in Iraq

    Directory of Open Access Journals (Sweden)

    Hafidh I. Al-Sadi

    2014-01-01

    Full Text Available This study was performed to evaluate pathology of experimental Encephalitozoon cuniculi (Iraqi isolate infection in normal and immunosuppressed mice. Pathological changes were not seen in negative control mice while secondary bacterial infections were noted in the lungs, kidneys, and heart of mice given dexamethasone. Typical E. cuniculi infection lesions were found in brain, livers, lungs, and kidneys of mice given 107  E. cuniculi spores/mouse orally. These lesions were in the form of nonsuppurative meningoencephalitis with vasculitis in brain, interstitial inflammation with infiltration of both lymphocytes and plasma cells in lung tissue, and nonsuppurative interstitial (focal and diffuse nephritis, presence of vacuole containing mature and immature spores in enterocytes within the tips of villi, and lymphoiod hyperplasia of the white pulp and vasculitis of the intratrabecular vessels. Mice that were given 107  E. cuniculi spores/mouse orally showed lesions similar to those observed in the previous group (vasculitis and granulomas but the lesions were more severe and widespread. In conclusion, this is the first report of experimental E. cuniculi infection induced by E. cuniculi isolated from a naturally infected rabbit in Iraq and that infection became more severe and widespread upon the administration of dexaethasone.

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

    Directory of Open Access Journals (Sweden)

    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.$?

  5. Dirofilaria immitis and D. repens show circadian co-periodicity in naturally co-infected dogs

    Czech Academy of Sciences Publication Activity Database

    Ionică, A.M.; Matei, I.A.; D'Amico, G.; Bel, L.; Dumitrache, M.O.; Modrý, David; Mihalca, A. D.

    2017-01-01

    Roč. 10, FEB 28 (2017), č. článku 116. ISSN 1756-3305 Institutional support: RVO:60077344 Keywords : periodicity * microfilariae * co-infection * Dirofilaria immitis * Dirofilaria repens Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 3.080, year: 2016

  6. HIV-infected persons with type 2 diabetes show evidence of endothelial dysfunction and increased inflammation

    DEFF Research Database (Denmark)

    Hove-Skovsgaard, Malene; Gaardbo, Julie Christine; Kolte, Lilian

    2017-01-01

    BACKGROUND: Increased incidence of cardiovascular diseases (CVD) in both HIV infection and type 2 diabetes (T2D) compared to the general population has been described. Little is known about the combined effect of HIV infection and T2D on inflammation and endothelial function, both of which may...... without T2D (HIV-T2D-)). Groups were matched on age and sex. High sensitive C-reactive protein (hsCRP) was used to determine inflammation (cut-off 3 mg/L). The marker of endothelial dysfunction asymmetric dimethylarginine (ADMA) was measured using high performance liquid chromatography. Trimethylamine.......001), which was mainly driven by a close correlation in HIV + T2D+ (rs = 0.63, p = 0.001). CONCLUSION: Elevated inflammation and evidence of endothelial dysfunction was found in HIV-infected persons with T2D. The effect on inflammation was mainly driven by T2D, while both HIV infection and T2D may contribute...

  7. Histopathological changes during experimental infections of calves with Cooperia punctata.

    Science.gov (United States)

    Rodrigues, R R; Gennari, S M; Guerra, J L; Contieri, M B; Abdalla, A L; Vitti, D M S S

    2004-06-01

    Eleven male two-month-old Holstein calves were used to determine the pathological changes induced by a Cooperia punctata infection. After weaning, ten calves received a single oral dose of 45,000 C. punctata infective larvae. One calf remained as a non-infected control. Groups of two calves were killed on days 7, 14, 21, 28 and 35 post-infection (p.i.) for determination of worm burdens and histopathological evaluation. The small intestine was sub-divided into three sections of approximately equal length, and representative samples of mucosa were fixed in 10% formalin, cut, and stained with haematoxylin-eosin. Samples of intestinal contents and mucosal digests were taken and fixed in 10% formalin for an estimation of total worm burdens. An increase in the number of adult parasites and a decrease in the number of larvae were observed with time (P<0.001). A higher concentration of worms was found in the first segment of the small intestine during the five weeks of observation. Histology showed larvae in the intestinal mucosa on day 7 p.i., with a discrete increase in the cellular response. Adult worms and a marked cellular infiltrate with eosinophils and neutrophils were present on day 21 p.i., and these persisted until day 35 p.i. Microcysts resulting from worm destruction were observed from day 21 p.i.

  8. RGMA and IL21R show association with experimental inflammation and multiple sclerosis

    DEFF Research Database (Denmark)

    Nohra, R; Beyeen, A D; Guo, J P

    2010-01-01

    31 showed linkage to EAE, PIA, anti-MOG antibodies and levels of tumor necrosis factor (TNF) and IL-6. Confidence intervals defined a limited set of potential candidate genes, with the most interesting being RGMA, IL21R and IL4R. We tested the association with multiple sclerosis (MS) in a Nordic case...... (EAE), anti-MOG antibodies and pristane-induced arthritis (PIA) in advanced intercross lines (AILs). Analysis in the tenth and twelfth generation of AILs resolved the region in two narrow QTL, Eae30 and Eae31. Eae30 showed linkage to MOG-EAE, anti-MOG antibodies and levels of interleukin-6 (IL-6). Eae...

  9. HIV-infected persons with type 2 diabetes show evidence of endothelial dysfunction and increased inflammation.

    Science.gov (United States)

    Hove-Skovsgaard, Malene; Gaardbo, Julie Christine; Kolte, Lilian; Winding, Kamilla; Seljeflot, Ingebjørg; Svardal, Asbjørn; Berge, Rolf Kristian; Gerstoft, Jan; Ullum, Henrik; Trøseid, Marius; Nielsen, Susanne Dam

    2017-03-29

    Increased incidence of cardiovascular diseases (CVD) in both HIV infection and type 2 diabetes (T2D) compared to the general population has been described. Little is known about the combined effect of HIV infection and T2D on inflammation and endothelial function, both of which may contribute to elevated risk of CVD. Cross-sectional study including 50 HIV-infected persons on combination anti-retroviral therapy (cART), with HIV RNA inflammation (cut-off 3 mg/L). The marker of endothelial dysfunction asymmetric dimethylarginine (ADMA) was measured using high performance liquid chromatography. Trimethylamine-N-oxide (TMAO), a microbiota-dependent, pro-atherogenic marker was measured using stable isotope dilution LC/MS/MS. The percentage of HIV + T2D+, HIV + T2D-, HIV-T2D+, and HIV-T2D- with hsCRP above cut-off was 50%, 19%, 47%, and 11%, respectively. HIV + T2D+ had elevated ADMA (0.67 μM (0.63-0.72) compared to HIV + T2D- (0.60 μM (0.57-0.64) p = 0.017), HIV-T2D+ (0.57 μM (0.51-63) p = 0.008), and HIV-T2D- (0.55 μM (0.52-0.58) p inflammation and evidence of endothelial dysfunction was found in HIV-infected persons with T2D. The effect on inflammation was mainly driven by T2D, while both HIV infection and T2D may contribute to endothelial dysfunction. Whether gut microbiota is a contributing factor to this remains to be determined.

  10. Efficiency of the oral, intramuscular and subcutaneous routes for the experimental infection of hamster and sheep with Schistosoma bovis.

    Science.gov (United States)

    Oleaga, Ana; Ramajo, Vicente

    2004-09-20

    The percutaneous administration of cercariae is the usual method for experimental infections with Schistosoma bovis. These procedures are laborious and have important inconveniences when working with a large number of animals, especially if they are ruminants. In the present study, the efficiency of the oral, intramuscular and subcutaneous routes are evaluated by comparison with the percutaneous route in experimental infections with S. bovis. The infections developed in hamsters and sheep were evaluated taking as a basis the parasite burden, the concentrations of eggs in tissues and the levels of anti-Schistosoma antibodies. The oral infection failed in both hamsters and sheep. The administration of the cercariae by the intramuscular route was effective in sheep, developing infections of intensity similar to that of the infections acquired percutaneously. In hamsters, on the contrary, although all the animals developed the infection, they were very little intense. The injection of the cercariae by the subcutaneous route induces acceptable infections in hamsters and can also be an alternative route to percutaneous exposure. The levels of the anti-Schistosoma bovis antibodies detected in hamster and sheep were proportional to the number of worms present, which shows that the humoral response is a good indicator of the intensity of the infections. It can be concluded that the intramuscular route is a good alternative to the percutaneous route for experimental infections of sheep with S. bovis. Likewise, the subcutaneous route can also substitute, with some advantages, the percutaneous infections in hamsters.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1979-02-01

    The capability of radionuclide imaging to detect experimental aortic valve infective endocarditis was assessed with indium-111 (/sup 111/In)-labeled blood cells. Sequential cardiac imaging and tissue distribution studies were obtained in 17 rabbits with infective endocarditis after administration of /sup 111/-In-platelets and in five after /sup 111/In-polymorphonuclear leukocytes. Forty-eight to 72 hours after platelet administration, in vivo imaging demonstrated abnormal /sup 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. /sup 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, /sup 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 /sup 111/In platelet scintigraphs nor abnormal cardiac tissue uptake. Likewise, noncellular /sup 111/In was not concentrated to any significant extent in three animals with infective endocarditis.This study demonstrates that /sup 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.

  12. Imaging experimental infective endocarditis with indium-111-labeled blood cellular components. [Rabbits, aortic valve

    Energy Technology Data Exchange (ETDEWEB)

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

    1979-02-01

    The capability of radionuclide imaging to detect experimental aortic valve infective endocarditis was assessed with indium-111 (/sup 111/In)-labeled blood cells. Sequential cardiac imaging and tissue distribution studies were obtained in 17 rabbits with infective endocarditis after administration of /sup 111/In-platelets and in five after /sup 111/In-polymorphonuclear leukocytes. Forty-eight to 72 hours after platelet administration, in vivo imaging demonstrated abnormal /sup 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. /sup 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, /sup 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 /sup 111/In-platelet scintigraphs nor abnormal cardiac tissue uptake. Likewise, noncellular /sup 111/In was not concentrated to any significant extent in three animals with infective endocarditis. This study demonstrates that /sup 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.

  13. 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 ... juice. Commercially available cranberry juice cocktail also significantly reduced (P juice (P juice, were tested...... 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...

  14. Failure to show decrease in small pulmonary blood vessels in rats with experimental pulmonary hypertension.

    OpenAIRE

    Kay, J M; Suyama, K L; Keane, P M

    1982-01-01

    We induced chronic pulmonary hypertension in one group of rats by exposing them to chronic hypobaric hypoxia (380 mm Hg for three weeks) and in another group by administering a single subcutaneous dose of monocrotaline (60 mg/kg body weight). Both groups of rats showed increase of the right ventricular mean systolic blood pressure and right ventricular hypertrophy. We measured the surface area of histological sections of the left or right lungs and counted all small blood vessels with an exte...

  15. Next-generation sequencing shows West Nile virus quasispecies diversification after a single passage in a carrion crow (Corvus corone) in vivo infection model.

    Science.gov (United States)

    Dridi, M; Rosseel, T; Orton, R; Johnson, P; Lecollinet, S; Muylkens, B; Lambrecht, B; Van Borm, S

    2015-10-01

    West Nile virus (WNV) occurs as a population of genetic variants (quasispecies) infecting a single animal. Previous low-resolution viral genetic diversity estimates in sampled wild birds and mosquitoes, and in multiple-passage adaptation studies in vivo or in cell culture, suggest that WNV genetic diversification is mostly limited to the mosquito vector. This study investigated genetic diversification of WNV in avian hosts during a single passage using next-generation sequencing. Wild-captured carrion crows were subcutaneously infected using a clonal Middle-East WNV. Blood samples were collected 2 and 4 days post-infection. A reverse-transcription (RT)-PCR approach was used to amplify the WNV genome directly from serum samples prior to next-generation sequencing resulting in an average depth of at least 700 ×  in each sample. Appropriate controls were sequenced to discriminate biologically relevant low-frequency variants from experimentally introduced errors. The WNV populations in the wild crows showed significant diversification away from the inoculum virus quasispecies structure. By contrast, WNV populations in intracerebrally infected day-old chickens did not diversify from that of the inoculum. Where previous studies concluded that WNV genetic diversification is only experimentally demonstrated in its permissive insect vector species, we have experimentally shown significant diversification of WNV populations in a wild bird reservoir species.

  16. Electromagnetic radiation influence on clinical course of experimental wound infection

    Directory of Open Access Journals (Sweden)

    Pronina Е.А.

    2010-09-01

    Full Text Available The article gives close attention to the study of electromagnetic radiation influence (EMR at the frequency of molecular spectrum absorption and radiation (MSAR of nitric oxide (150 GHz and atmospheric oxygen (129 GHz on the clinical course of experimental wound infection caused by antibiotic-sensitive and antibiotic-resistant strains of Pseudomonas aeruginosa. The panoramic spectrometric measuring complex, developed in Saratov Scientific Research Institute of Measuring Equipment was used while carrying out the research. Electromagnetic vibrations of extremely high frequencies were stimulated in this complex imitating the atmospheric oxygen and nitric oxide absorption and radiation molecular spectrum structure. The experiments proved the fact that exposure to radiation at the frequency of molecular spectrum absorption and radiation (MSAR of nitric oxide and atmospheric oxygen had positive impact on the course of traumatic process

  17. Natural Schistosoma mansoni infection in Nectomys squamipes: histopathological and morphometric analysis in comparison to experimentally infected N. squamipes and C3H/He mice

    Directory of Open Access Journals (Sweden)

    Michele Costa-Silva

    2002-10-01

    Full Text Available Histopathologic and morphometric (area, perimeter, major and minor diameters analysis of hepatic granulomas isolated from twelve naturally infected Nectomys squamipes were compared to four experimentally infected ones and six C3H/He mice. Liver paraffin sections were stained for cells and extracellular matrix. Both groups of N. squamipes presented peculiar granulomas consisting predominantly of large macrophages, full of schistosome pigment, characterizing an exudative-macrophage granuloma type, smaller than the equivalent granuloma type in mouse. Naturally infected animals exhibited granulomas in different stages of development, including large number of involutional types. Morphometric analysis showed that all measurements were smaller in naturally infected animals than in other groups. The results demonstrated that both N. squamipes groups reproduced, with small variations, the hepatic granuloma aspects already described in cricetidium (Calomys callosus, showing a genetic tendency to set up strong macrophage responses and small granulomas. Unexpectedly, natural infection did not engender distinguished histopathological characteristics distinct from those derived from experimental single infection, showing changes predominantly secondary to the duration of infection. It appears that the variability of the inocula (and the number of infections? interfere more with the quantity than with the quality of the pathological changes, denoting some morpho-functional determinism in the response to schistosomal infection dependent on the animal species.

  18. Antibody and inflammatory responses in laying hens with experimental primary infections of Ascaridia galli.

    Science.gov (United States)

    Marcos-Atxutegi, C; Gandolfi, B; Arangüena, T; Sepúlveda, R; Arévalo, M; Simón, F

    2009-04-06

    Ascaridia galli, an intestinal nematode that affects hens and other domestic and wild birds, causes economic losses in avian exploitations. The present work shows that A. galli stimulates a strong antibody response as well as an intense inflammatory reaction, in the intestinal mucous of experimentally infected Lohmann Brown laying hens. IgG antibodies against soluble extracts of A. galli embrionated eggs and adult worms, were detected in both blood and yolks eggs from infected hens during a period of 105 days after the infection. This indicates that hens transfer to their offspring a part of the IgG antibodies produced when they become infected. The antigens responsible for the stimulation of specific IgG were molecules of 30-34, 44-54 and 58-90 kDa, while in the yolk eggs of infected hens a reactivity directed against antigens of molecular weight (M(w)) lower than 50 kDa was detected. Histology revealed traumatic lesions with leukocyte infiltration, and inflammation of the intestinal wall of the infected hens after 105 days of initial infection. The possible influence of the immune and inflammatory response on the population dynamics of the parasite is discussed.

  19. Dual RNAseq shows the human mucosal immunity protein, MUC13, is a hallmark of Plasmodium exoerythrocytic infection

    KAUST Repository

    LaMonte, Gregory

    2017-10-03

    The exoerythrocytic stage of Plasmodium malaria infection is a critical window for prophylactic intervention. Using a genome-wide dual RNA sequencing of flow-sorted infected and uninfected hepatoma cells we identify the human mucosal immunity gene, Mucin13 (MUC13), as strongly upregulated during Plasmodium exoerythrocytic hepatic-stage infection. We confirm that MUC13 expression is upregulated in hepatoma cell lines and primary hepatocytes. In immunofluorescence assays, host MUC13 protein expression distinguishes infected cells from adjacent uninfected cells and shows similar colocalization with parasite biomarkers such as UIS4 and HSP70. We further show that localization patterns are species independent, distinguishing both P. berghei and P. vivax infected cells, and that MUC13 can be used to identify compounds that inhibit parasite replication in hepatocytes across all Human-infecting Plasmodium species. This data presents a novel interface of host-parasite interactions in Plasmodium, in that a component of host mucosal immunity is reprogrammed to assist the progression of infection.

  20. Lactation curve and milk quality of goats experimentally infected with Trypanosoma vivax.

    Science.gov (United States)

    Lopes, Francisco Canindé; de Paiva, Kaliane Alessandra Rodrigues; Coelho, Wesley Adson Costa; Nunes, Francisco Vítor Aires; da Silva, Jardel Bezerra; de Gouveia Mendes da Escóssia Pinheiro, Carolina; de Macêdo Praça, Layanne; Silva, Jean Berg Alves; Alves Freitas, Carlos Iberê; Batista, Jael Soares

    2016-08-01

    The present study aimed to evaluate the effects of Trypanosoma vivax infection on the shape of the lactation curve and the milk quality of dairy goats experimentally infected with T. vivax. In total, twenty Saanen goats, aged 26-30 months and the same number of calving (two calvings), were divided into two experimental groups: an infected group, consisting of ten goats intravenously infected with 0.5 ml of blood containing approximately 1.25 × 10(5) trypomastigotes of T. vivax and ten uninfected animals as the control group. Clinical tests and hematocrit, parasitemia, and serum biochemistry evaluations were performed on all of the goats. Milk production was measured daily for 152 days by hand milking the goats and weighing the milk. Every seven days, physiochemical analyses were performed to evaluate the milk. Wood's nonlinear model was used to analyze the lactation curve parameters. The infected goats had high levels of parasitemia and hyperthermia, significantly reduced hematocrit, serum total protein, albumin, and glucose levels and increased cholesterol and urea concentrations. Wood's model indicated that the milk production of goats in the infected group declined sharply over a short period of time and produced a flattened yield curve and significant difference (P physico-chemical properties of the milk, including the fat content, defatted dry extracts (DDE) and protein content, decreased significantly (P < 0.05) in the goats in the infected group compared with those in the control group. The T. vivax-infected goats showed reduction in milk production, persistence of lactation, and fat levels, the defatted dry extract (DDE) content, and protein, changing the quality of milk. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. 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

  2. Infants at familial risk for depression show a distinct pattern of cortisol response to experimental challenge.

    Science.gov (United States)

    Waters, Cerith S; van Goozen, Stephanie; Phillips, Rebecca; Swift, Naomi; Hurst, Sarah-Louise; Mundy, Lisa; Jones, Roland; Jones, Ian; Goodyer, Ian; Hay, Dale F

    2013-09-25

    The aim of the study was to examine the link between maternal depression and the infant's HPA axis functioning in relation to a sequence of emotional challenges at 12 months postpartum, while controlling for maternal anxiety disorder and general sociodemographic risk. Two hundred and fifty-seven infants whose mothers had been interviewed in pregnancy, as part of a prospective longitudinal study of a nationally representative sample of U.K. families, were individually tested in the laboratory and then observed during a simulated birthday party scenario. Three cortisol samples were taken over the course of 1½ h of afternoon testing. The cortisol levels of infants whose mothers had no history of depression decreased significantly after individual testing, and rose again significantly in response to the birthday party challenge. In contrast, infants whose mothers had been diagnosed with depression before conception, during pregnancy or in the first 6 months postpartum showed no decrease from the initially elevated levels at entry to the laboratory and a less marked increase in response to the party. The study does not employ a traditional stress paradigm; instead it introduces a novel design to assess HPA axis functioning in relation to everyday emotional challenges. The findings suggest that altered responses to mildly challenging events in infancy may be a marker for infants' familial risk for depressive illness. © 2013 Published by Elsevier B.V.

  3. Factors secreted from dental pulp stem cells show multifaceted benefits for treating experimental rheumatoid arthritis.

    Science.gov (United States)

    Ishikawa, Jun; Takahashi, Nobunori; Matsumoto, Takuya; Yoshioka, Yutaka; Yamamoto, Noriyuki; Nishikawa, Masaya; Hibi, Hideharu; Ishigro, Naoki; Ueda, Minoru; Furukawa, Koichi; Yamamoto, Akihito

    2016-02-01

    Rheumatoid arthritis (RA) is an autoimmune disease characterized by synovial hyperplasia and chronic inflammation, which lead to the progressive destruction of cartilage and bone in the joints. Numerous studies have reported that administrations of various types of MSCs improve arthritis symptoms in animal models, by paracrine mechanisms. However, the therapeutic effects of the secreted factors alone, without the cell graft, have been uncertain. Here, we show that a single intravenous administration of serum-free conditioned medium (CM) from human deciduous dental pulp stem cells (SHED-CM) into anti-collagen type II antibody-induced arthritis (CAIA), a mouse model of rheumatoid arthritis (RA), markedly improved the arthritis symptoms and joint destruction. The therapeutic efficacy of SHED-CM was associated with an induction of anti-inflammatory M2 macrophages in the CAIA joints and the abrogation of RANKL expression. SHED-CM specifically depleted of an M2 macrophage inducer, the secreted ectodomain of sialic acid-binding Ig-like lectin-9 (ED-Siglec-9), exhibited a reduced ability to induce M2-related gene expression and attenuate CAIA. SHED-CM also inhibited the RANKL-induced osteoclastogenesis in vitro. Collectively, our findings suggest that SHED-CM provides multifaceted therapeutic effects for treating CAIA, including the ED-Siglec-9-dependent induction of M2 macrophage polarization and inhibition of osteoclastogenesis. Thus, SHED-CM may represent a novel anti-inflammatory and reparative therapy for RA. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Burkholderia pseudomallei Colony Morphotypes Show a Synchronized Metabolic Pattern after Acute Infection.

    Science.gov (United States)

    Gierok, Philipp; Kohler, Christian; Steinmetz, Ivo; Lalk, Michael

    2016-03-01

    Burkholderia pseudomallei is a water and soil bacterium and the causative agent of melioidosis. A characteristic feature of this bacterium is the formation of different colony morphologies which can be isolated from environmental samples as well as from clinical samples, but can also be induced in vitro. Previous studies indicate that morphotypes can differ in a number of characteristics such as resistance to oxidative stress, cellular adhesion and intracellular replication. Yet the metabolic features of B. pseudomallei and its different morphotypes have not been examined in detail so far. Therefore, this study aimed to characterize the exometabolome of B. pseudomallei morphotypes and the impact of acute infection on their metabolic characteristics. We applied nuclear magnetic resonance spectroscopy (1H-NMR) in a metabolic footprint approach to compare nutrition uptake and metabolite secretion of starvation induced morphotypes of the B. pseudomallei strains K96243 and E8. We observed gluconate production and uptake in all morphotype cultures. Our study also revealed that among all morphotypes amino acids could be classified with regard to their fast and slow consumption. In addition to these shared metabolic features, the morphotypes varied highly in amino acid uptake profiles, secretion of branched chain amino acid metabolites and carbon utilization. After intracellular passage in vitro or murine acute infection in vivo, we observed a switch of the various morphotypes towards a single morphotype and a synchronization of nutrient uptake and metabolite secretion. To our knowledge, this study provides first insights into the basic metabolism of B. pseudomallei and its colony morphotypes. Furthermore, our data suggest, that acute infection leads to the synchronization of B. pseudomallei colony morphology and metabolism through yet unknown host signals and bacterial mechanisms.

  5. Influence of body condition on influenza a virus infection in mallard ducks: Experimental infection data

    Science.gov (United States)

    Arsnoe, D.M.; Ip, Hon S.; Owen, J.C.

    2011-01-01

    Migrating waterfowl are implicated in the global spread of influenza A viruses (IAVs), and mallards (Anas platyrhynchos) are considered a particularly important IAV reservoir. Prevalence of IAV infection in waterfowl peaks during autumn pre-migration staging and then declines as birds reach wintering areas. Migration is energetically costly and birds often experience declines in body condition that may suppress immune function. We assessed how body condition affects susceptibility to infection, viral shedding and antibody production in wild-caught and captive-bred juvenile mallards challenged with low pathogenic avian influenza virus (LPAIV) H5N9. Wild mallards (n = 30) were separated into three experimental groups; each manipulated through food availability to a different condition level (-20%, -10%, and normal ??5% original body condition), and captive-bred mallards (n = 10) were maintained at normal condition. We found that wild mallards in normal condition were more susceptible to LPAIV infection, shed higher peak viral loads and shed viral RNA more frequently compared to birds in poor condition. Antibody production did not differ according to condition. We found that wild mallards did not differ from captive-bred mallards in viral intensity and duration of infection, but they did exhibit lower antibody titers and greater variation in viral load. Our findings suggest that reduced body condition negatively influences waterfowl host competence to LPAIV infection. This observation is contradictory to the recently proposed condition-dependent hypothesis, according to which birds in reduced condition would be more susceptible to IAV infection. The mechanisms responsible for reducing host competency among birds in poor condition remain unknown. Our research indicates body condition may influence the maintenance and spread of LPAIV by migrating waterfowl. ?? 2011 Arsnoe et al.

  6. 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.

  7. Persistent immune responses in late infection and after treatment in experimental Schistosoma bovis infections in goats.

    Science.gov (United States)

    Sörén, K; Monrad, J; Johansen, M V; Lindberg, R

    2009-06-01

    This study explored host immune responses and their possible relationship to the anti-fecundity phenomenon in Schistosoma bovis-infected goats. The design comprised a primary infection with or without treatment at week (wk) 13, and with or without challenge at wk 36. Necropsy was performed at 36 or 52wk. Serum levels of anti-egg IgG, and anti-worm IgG and IgM, were measured by ELISA. In chronic infection, anti-worm antibodies stayed high, reflecting persisting worm burdens, whereas anti-egg IgG remained high despite minimized egg excretion. After treatment, anti-worm IgM and anti-egg IgG were minimized, but anti-worm IgG remained above the values of the uninfected controls. Histopathology showed lowered numbers of perioval granulomas in chronic infection and resolution of liver fibrosis with time, but intestinal lymphoplasmacytic perivasculitis and hepatic eosinophilic infiltrates were maintained at wk 52. Significant splenic plasmacytosis persisted after treatment. The results indicated that persistent immune responses, in chronically infected and in treated goats, may explain sustained worm fecundity depression at challenge infection.

  8. Experimental Infection of Cats and Dogs with West Nile Virus

    OpenAIRE

    Austgen, Laura E.; Bowen, Richard A.; Bunning, Michel L.; Davis, Brent S.; Mitchell, Carl J.; Chang, Gwong-Jen J.

    2004-01-01

    Domestic dogs and cats were infected by mosquito bite and evaluated as hosts for West Nile virus (WNV). Viremia of low magnitude and short duration developed in four dogs but they did not display signs of disease. Four cats became viremic, with peak titers ranging from 103.0 to 104.0 PFU/mL. Three of the cats showed mild, non-neurologic signs of disease. WNV was not isolated from saliva of either dogs or cats during the period of viremia. An additional group of four cats were exposed to WNV o...

  9. 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...... 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...... polymorphonuclear) cells. F. psychrophilus infection in rainbow trout fry involves the monocyte-macrophage system extensively, and the concurrent localization of bacteria in the skin ulcers and retinal inflammation points to the probable involvement of the bacterium in the development of the lesions which...

  10. Experimental infection and co-infection of dogs with Anaplasma platys and Ehrlichia canis: hematologic, serologic and molecular findings

    Directory of Open Access Journals (Sweden)

    Diniz PPVP

    2010-04-01

    Full Text Available Abstract Background Rhipicephalus sanguineus is a ubiquitous tick responsible for transmitting Ehrlichia canis and most likely Anaplasma platys to dogs, as either single or co-infections. The objective of this study was to assess the effects of either simultaneous or sequential experimental infections with E. canis and A. platys on hematological and serological parameters, duration of infection, and efficacy of doxycycline therapy in dogs infected with one or both organisms. Six dogs per group were either uninfected, A. platys infected, E. canis infected, A. platys and E. canis co-infected, A. platys infected and E. canis challenged or E. canis infected and A. platys challenged at day 112 post-infection (PI. Doxycycline treatment was initiated at 211 days PI, followed by dexamethasone immunosuppression beginning 410 days PI. Results Initially, transient decreases in hematocrit occurred in all groups infected with E. canis, but the mean hematocrit was significantly lower in the A. platys and E. canis co-infected group. All dogs except the controls developed marked thrombocytopenia after initial infection followed by gradually increased platelet counts by 112 days PI in groups with the single infections, while platelet counts remained significantly lower in the A. platys and E. canis co-infected group. Both sequential and simultaneous infections of A. platys and E. canis produced an enhanced humoral immune response to A. platys when compared to infection with A. platys alone. Likewise, co-infection with E. canis and A. platys resulted in a more persistent A. platys infection compared to dogs infected with A. platys only, but nearly all A. platys infected dogs became A. platys PCR negative prior to doxycycline treatment. E. canis infected dogs, whether single or co-infected, remained thrombocytopenic and E. canis PCR positive in blood for 420 days. When treated with doxycycline, all E. canis infected dogs became E. canis PCR negative and the

  11. 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.

  12. A Simple Experimental Setup to Clearly Show That Light Does Not Recombine after Passing through Two Prisms

    Science.gov (United States)

    Garcia-Molina, Rafael; del Mazo, Alejandro; Velasco, Santiago

    2018-01-01

    We present a simple and cheap experimental setup that clearly shows how the colors of the white light spectrum after passing a prism do not recombine when emerging from an identical second prism, as it is still found in many references.

  13. Storage of gastrointestinal nematode infective larvae for species preservation and experimental infections.

    Science.gov (United States)

    Chylinski, C; Cortet, J; Sallé, G; Jacquiet, P; Cabaret, J

    2015-02-01

    Techniques to preserve the infective third-stage larvae (L3) of gastrointestinal nematodes are of considerable interest to preserve rare species and to maintain a stable source for routine experimental infections. This study compares the relative pros and cons of the two most common techniques, cryopreservation and refrigeration by comparing how they influence consequent infection outcome parameters in terms of life-history traits and fitness as a function of time using the gastrointestinal nematode of sheep Haemonchus contortus as a study species. Establishment capacity was found to be significantly reduced in cryopreserved stocks of L3 compared to refrigerated stocks, but this was followed by significant increases in their fecundity. Refrigeration did not affect L3 stocks consequent fitness by 16 months (the maximum examined) although they did incur a significant reduction in establishment, followed once again by an augmentation in fecundity. The study highlights potential areas for bias in comparing studies using L3 larvae maintained for different periods of time under different techniques.

  14. Dissemination of Salmonella enteritidis by experimentally-infected pigeons

    Directory of Open Access Journals (Sweden)

    ÁH Albuquerque

    2013-09-01

    Full Text Available Two groups of domestic pigeons (Columba livia were experimentally infected orally with doses of 9.5 x10(7 and 9.5 x10(9 CFU/mL (group A and B, respectively of a Salmonella Enteritidis (SE strain isolated from chickens. None of the used doses caused mortality of the inoculated birds; however, the pathogen was successfully recovered from the liver and spleen of group B birds on day 7 post-inoculation (dpi. Pathogen shedding, as evaluated through cloacal swabs, occurred in both groups until the 14th day of observation (p <0.05. Among all fecal samples collected from group B (n=4, three different birds shed the pathogen in their feces, out of which two were positive on 3 dpi and one on 7 dpi. The same number of fecal samples was evaluated in group A and only one bird shed the pathogen, on 7 and 14 dpi. The concentration of the microorganism in the feces was lower in group A than any sample from Group B. Salmonella Enteritidis isolated from chickens, when inoculated in pigeons, may be recovered from feces, cloacal swabs and organs, and these birds may contaminate poultry causing economic losses as well as posing a risk to the public health.

  15. Pathology of experimental Escherichia coli infection in mice: a ...

    African Journals Online (AJOL)

    . Mice were sacrificed after 72hrs and the glands examined bacteriological and histologically. Positive bacteriological and histological results were required for a diagnosis of infection. The infective dose fifty (ID50) for the nine stereotypes ...

  16. Young Sprague Dawley rats infected by Plasmodium berghei: A relevant experimental model to study cerebral malaria.

    Directory of Open Access Journals (Sweden)

    Sokhna Keita Alassane

    Full Text Available Cerebral malaria (CM is the most severe manifestation of human malaria yet is still poorly understood. Mouse models have been developed to address the subject. However, their relevance to mimic human pathogenesis is largely debated. Here we study an alternative cerebral malaria model with an experimental Plasmodium berghei Keyberg 173 (K173 infection in Sprague Dawley rats. As in Human, not all infected subjects showed cerebral malaria, with 45% of the rats exhibiting Experimental Cerebral Malaria (ECM symptoms while the majority (55% of the remaining rats developed severe anemia and hyperparasitemia (NoECM. These results allow, within the same population, a comparison of the noxious effects of the infection between ECM and severe malaria without ECM. Among the ECM rats, 77.8% died between day 5 and day 12 post-infection, while the remaining rats were spontaneously cured of neurological signs within 24-48 hours. The clinical ECM signs observed were paresis quickly evolving to limb paralysis, global paralysis associated with respiratory distress, and coma. The red blood cell (RBC count remained normal but a drastic decrease of platelet count and an increase of white blood cell numbers were noted. ECM rats also showed a decrease of glucose and total CO2 levels and an increase of creatinine levels compared to control rats or rats with no ECM. Assessment of the blood-brain barrier revealed loss of integrity, and interestingly histopathological analysis highlighted cyto-adherence and sequestration of infected RBCs in brain vessels from ECM rats only. Overall, this ECM rat model showed numerous clinical and histopathological features similar to Human CM and appears to be a promising model to achieve further understanding the CM pathophysiology in Humans and to evaluate the activity of specific antimalarial drugs in avoiding/limiting cerebral damages from malaria.

  17. Young Sprague Dawley rats infected by Plasmodium berghei: A relevant experimental model to study cerebral malaria.

    Science.gov (United States)

    Keita Alassane, Sokhna; Nicolau-Travers, Marie-Laure; Menard, Sandie; Andreoletti, Olivier; Cambus, Jean-Pierre; Gaudre, Noémie; Wlodarczyk, Myriam; Blanchard, Nicolas; Berry, Antoine; Abbes, Sarah; Colongo, David; Faye, Babacar; Augereau, Jean-Michel; Lacroux, Caroline; Iriart, Xavier; Benoit-Vical, Françoise

    2017-01-01

    Cerebral malaria (CM) is the most severe manifestation of human malaria yet is still poorly understood. Mouse models have been developed to address the subject. However, their relevance to mimic human pathogenesis is largely debated. Here we study an alternative cerebral malaria model with an experimental Plasmodium berghei Keyberg 173 (K173) infection in Sprague Dawley rats. As in Human, not all infected subjects showed cerebral malaria, with 45% of the rats exhibiting Experimental Cerebral Malaria (ECM) symptoms while the majority (55%) of the remaining rats developed severe anemia and hyperparasitemia (NoECM). These results allow, within the same population, a comparison of the noxious effects of the infection between ECM and severe malaria without ECM. Among the ECM rats, 77.8% died between day 5 and day 12 post-infection, while the remaining rats were spontaneously cured of neurological signs within 24-48 hours. The clinical ECM signs observed were paresis quickly evolving to limb paralysis, global paralysis associated with respiratory distress, and coma. The red blood cell (RBC) count remained normal but a drastic decrease of platelet count and an increase of white blood cell numbers were noted. ECM rats also showed a decrease of glucose and total CO2 levels and an increase of creatinine levels compared to control rats or rats with no ECM. Assessment of the blood-brain barrier revealed loss of integrity, and interestingly histopathological analysis highlighted cyto-adherence and sequestration of infected RBCs in brain vessels from ECM rats only. Overall, this ECM rat model showed numerous clinical and histopathological features similar to Human CM and appears to be a promising model to achieve further understanding the CM pathophysiology in Humans and to evaluate the activity of specific antimalarial drugs in avoiding/limiting cerebral damages from malaria.

  18. Genetic resistance to experimental Cooperia oncophora infections in calves

    NARCIS (Netherlands)

    Albers, G.A.A.

    1981-01-01

    The variation in resistance of cattle to gastro-intestinal nematode infection was investigated in three experiments. Bull calves, aged three months and reared under uniform conditions, were artificially infected with infective larvae of Cooperia oncophora, a moderately

  19. Antibody response against Trichinella spiralis in experimentally infected rats is dose dependent

    Science.gov (United States)

    2011-01-01

    Domestic pigs are the main representatives of the domestic cycle of Trichinella spiralis that play a role in transmission to humans. In Europe, backyard pigs of small household farms are the most important risks for humans to obtain trichinellosis. Rats might play a role in the transmission of Trichinella spiralis from domestic to sylvatic animals and vice versa. In order to be able to investigate the role of wild rats in the epidemiology of T. spiralis in The Netherlands, we studied the dynamics of antibody response after T. spiralis infections in experimental rats, using infection doses ranging from very low (10 muscle larvae, ML, per rat) to very high (16 000 ML per rat). To evaluate the feasibility of rats surviving high infection doses with T. spiralis, clinical and pathological parameters were quantified. Serological tools for detecting T. spiralis in rats were developed to quantitatively study the correlation between parasite load and immunological response. The results show that an infection dose-dependent antibody response was developed in rats after infection with as low as 10 ML up to a level of 10 000 ML. A positive correlation was found between the number of recovered ML and serum antibody levels, although specific measured antibody levels correspond to a wide range of LPG values. Serum antibodies of rats that were infected even with 10 or 25 ML could readily be detected by use of the T. spiralis western blot 2 weeks post infection. We conclude that based on these low infection doses, serologic tests are a useful tool to survey T. spiralis in wild rats. PMID:22129040

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

    Directory of Open Access Journals (Sweden)

    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.

  1. Cellular immune responses of the rat to experimental infection with Dermatophilus congolensis.

    Science.gov (United States)

    Woodman, J P; Morrow, A M; Heron, I

    1990-11-01

    The host cell-mediated immune response was examined following experimentally-induced infection of rats with Dermatophilus congolensis, the causal agent of the skin disease dermatophilosis. Mononuclear cells (MC) isolated from Wistar rats 10 days following the induction of a third infection underwent a strong and specific proliferative response, as assessed by a [3H]thymidine incorporation assay, when cultured with various concentrations of inactivated D. congolensis cocci. Using specific monoclonal antibodies in an indirect fluorescent antibody test, this in vitro response was found to be characterised by a large expansion of the W3/25 (T-helper phenotype) population to form 56% of the total. Finally, the primed and stimulated MC were assessed for their ability to produce factors capable of inhibiting macrophage migration. The culture supernatants of D. congolensis-stimulated MC from infected rats caused significant migration inhibition of normal rat peritoneal exudate cells, whilst the supernatants of similarly-stimulated MC from naive rats failed to cause significant inhibition. The results show that a MC subpopulation becomes primed following experimentally-induced infection with D. congolensis and becomes activated after subsequent, in vitro, exposure.

  2. Performance of commercially available serological diagnostic tests to detect Leishmania infantum infection on experimentally infected dogs.

    Science.gov (United States)

    Rodríguez-Cortés, Alhelí; Ojeda, Ana; Todolí, Felicitat; Alberola, Jordi

    2013-01-31

    Leishmania infantum (syn. Leishmania chagasi) is the etiological agent of a widespread serious zoonotic disease that affects both humans and dogs. Prevalence and incidence of the canine infection are important parameters to determine the risk and the ways to control this reemergent zoonosis. Unfortunately, there is not a gold standard test for Leishmania infection. Our aim was to assess the operative validity of commercial tests used to detect antibodies to Leishmania in serum samples from experimental infections. Three ELISA tests (LEISCAN(®) Leishmania ELISA Test, INGEZIM(®) LEISHMANIA, and INGEZIM(®) LEISHMANIA VET), three immunochromatographic tests (INGEZIM(®) LEISHMACROM, SNAP(®) Leishmania, and WITNESS(®) Leishmania), and one IFAT were evaluated. LEISCAN(®) Leishmania ELISA test achieved the highest sensitivity and accuracy (both 0.98). Specificity was 1 for all tests except for IFAT. All tests but IFAT obtained a positive predictive value of 1, while the maximum negative predictive value was achieved by LEISCAN(®) Leishmania ELISA Test (0.93). The best positive likelihood ratio was obtained by INGEZIM(®) LEISHMANIA VET (30.26), while the best negative likelihood ratio was obtained by LEISCAN(®) Leishmania ELISA Test (0.02). The highest diagnostic odds ratio was achieved by LEISCAN(®) Leishmania ELISA Test (729.00). The largest area under the ROC curve was obtained by LEISCAN(®) Leishmania ELISA Test (0.981). Quantitative ELISA based tests performmed better than qualitative tests ("Rapid Tests"), and the test best suited to detect Leishmania in infected dogs and to provide clinically useful information was LEISCAN(®) Leishmania ELISA Test. This and other results point also to the need of revising the status of IFAT as a gold standard for the diagnosis of leishmaniasis. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. 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...

  4. Clinico-biochemical responses of dogs to experimental infection with Babesia canis

    Directory of Open Access Journals (Sweden)

    M. Konto

    2014-03-01

    Full Text Available Aim: A study on the clinical and biochemical parameters of Nigerian dogs experimentally infected with Babesia canis was conducted. Materials and Methods: A total of ten naive dogs of both sex and aged between 6 months to 1 year, were used for the study. They were divided into two groups of five each- A (control and B (infected. Dogs in group B were infected with 1ml of Babesia canis positive infectious inoculum, while those in group A were left as uninfected control. Following infection, clinical and biochemical responses were analyzed in group B and compared with those in group A. Results: Clinical signs were observed on the infected dogs 2 days post infection, which included fever (100%, increase in pulse (80%, tachycardia (60% and inappetence (100%; followed by anorexia (40% and lethargy (100% on day 3; on the fourth day, pallor of the mucous membrane of the mouth and eye (100% and emaciation (100%; on day five, muscle tremor (20% and respiratory distress (20%; on day six, nervousness (20%, drooling salivation (20% and haemoglobinuria (80; on day seven, mucoid ocular discharge (40%; followed by the death of one dog on day 8 post infection. Other clinical signs recorded between days 1-14 post infection were ascites, edematous swelling of the whole body and hair erection. The biochemical changes showed that there was a significant (p < 0.05 rise in alkaline phosphatase (ALP values in infected dogs (58.50±1.4 compared with the control group (51.67±1.6. Also, there was a significant rise (p < 0.05 in the alanine amino transferase (ALT values of infected group (15.70±1. 8 compared with the control values (8.27±2.0. However, the mean values for creatinine of infected group (78.10±1.2 was significantly lower (p < 0.05 than that of the control (91.73±1.3. Similarly, the glucose levels for infected group (3.80±2.3 were significantly (p < 0.05 lower than that of control (5.35±2.1. Conclusion: It can be concluded that the disease runs an acute

  5. Effect of resinous extract from Commiphora swynnertonii (Burrt) on experimental coccidial infection in chickens.

    Science.gov (United States)

    Bakari, Gaymary G; Max, Robert A; Mdegela, Robinson H; Phiri, Elliot C J; Mtambo, Mkumbukwa M A

    2013-02-01

    A crude resinous extract from Commiphora swynnertonii was tested against an experimental coccidial infection in local chickens. A total of 80 growing chickens were randomly assigned into five groups, which received different treatments. Chickens in G1 were not infected with coccidian oocysts and therefore served as a negative control. All chickens in G2, G3, G4 and G5 were infected through oral administration of coccidian oocysts suspension at a dosed rate of 1.5 × 10(4) Eimeria spp. oocysts per bird. Starting from day 3 post-infection (p.i), chickens in different groups were treated for 7 consecutive days as follows: G1 and G2 (positive control) received 5 ml of normal saline as placebo, G3 and G4 were given the extract at 400 and 800 mg/kg bodyweight whereas G5 received anticoccidial drug. Clinical signs, bodyweights, oocysts counts and mortality rates were observed regularly. Results showed that oral administration of the resinous extract to chickens with coccidiosis significantly reduced mortality rate from 94 to 25 % and oocysts counts from 1.03 × 10(5) to 6.55 × 10(3) oocysts/g faeces (p < 0.05). Also a body condition score chart indicated less severe clinical signs of the disease in the groups which received the extract. Mean daily body weights were slightly reduced by the administration of the extract but this effect disappeared by day 7 p.i. These findings clearly indicate that resinous extract from C. swynnertonii has significant anticoccidial effect against experimental Eimeria spp. infection in chickens. A larger field trial to validate the use of the extract in chickens naturally infected with Eimeria spp. is required.

  6. Subunit Vaccines Consisting of Antigens from Dormant and Replicating Bacteria Show Promising Therapeutic Effect against Mycobacterium Bovis BCG Latent Infection.

    Science.gov (United States)

    Li, F; Kang, H; Li, J; Zhang, D; Zhang, Y; Dannenberg, A M; Liu, X; Niu, H; Ma, L; Tang, R; Han, X; Gan, C; Ma, X; Tan, J; Zhu, B

    2017-06-01

    To screen effective antigens as therapeutic subunit vaccines against Mycobacterium latent infection, we did bioinformatics analysis and literature review to identify effective antigens and evaluated the immunogenicity of five antigens highly expressed in dormant bacteria, which included Rv2031c (HspX), Rv2626c (Hrp1), Rv2007c (FdxA), Rv1738 and Rv3130c. Then, several fusion proteins such as Rv2007c-Rv2626c (F6), Rv2031c-Rv1738-Rv1733c (H83), ESAT6-Rv1738-Rv2626c (LT40), ESAT6-Ag85B-MPT64 -Mtb8.4 (EAMM), and EAMM-Rv2626c (LT70) were constructed and their therapeutic effects were evaluated in pulmonary Mycobacterium bovis Bacilli Calmette-Guérin (BCG) - latently infected rabbit or mouse models. The results showed that EAMM and F6 plus H83 had therapeutic effect against BCG latent infection in the rabbit model, respectively, and that the combination of EAMM with F6 plus H83 significantly reduced the bacterial load. In addition, the fusion proteins LT40 and LT70 consisting of multistage antigens showed promising therapeutic effects in the mouse model. We conclude that subunit vaccines consisting of both latency and replicating-associated antigens show promising therapeutic effects in BCG latent infection animal models. © 2017 The Foundation for the Scandinavian Journal of Immunology.

  7. Dendritic cell subtypes from lymph nodes and blood show contrasted gene expression programs upon Bluetongue virus infection.

    Science.gov (United States)

    Ruscanu, Suzana; Jouneau, Luc; Urien, Céline; Bourge, Mickael; Lecardonnel, Jérôme; Moroldo, Marco; Loup, Benoit; Dalod, Marc; Elhmouzi-Younes, Jamila; Bevilacqua, Claudia; Hope, Jayne; Vitour, Damien; Zientara, Stéphan; Meyer, Gilles; Schwartz-Cornil, Isabelle

    2013-08-01

    Human and animal hemorrhagic viruses initially target dendritic cells (DCs). It has been proposed, but not documented, that both plasmacytoid DCs (pDCs) and conventional DCs (cDCs) may participate in the cytokine storm encountered in these infections. In order to evaluate the contribution of DCs in hemorrhagic virus pathogenesis, we performed a genome-wide expression analysis during infection by Bluetongue virus (BTV), a double-stranded RNA virus that induces hemorrhagic fever in sheep and initially infects cDCs. Both pDCs and cDCs accumulated in regional lymph nodes and spleen during BTV infection. The gene response profiles were performed at the onset of the disease and markedly differed with the DC subtypes and their lymphoid organ location. An integrative knowledge-based analysis revealed that blood pDCs displayed a gene signature related to activation of systemic inflammation and permeability of vasculature. In contrast, the gene profile of pDCs and cDCs in lymph nodes was oriented to inhibition of inflammation, whereas spleen cDCs did not show a clear functional orientation. These analyses indicate that tissue location and DC subtype affect the functional gene expression program induced by BTV and suggest the involvement of blood pDCs in the inflammation and plasma leakage/hemorrhage during BTV infection in the real natural host of the virus. These findings open the avenue to target DCs for therapeutic interventions in viral hemorrhagic diseases.

  8. Buparvaquone is active against Neospora caninum in vitro and in experimentally infected mice

    Directory of Open Access Journals (Sweden)

    Joachim Müller

    2015-04-01

    Full Text Available The naphthoquinone buparvaquone is currently the only drug used against theileriosis. Here, the effects of buparvaquone were investigated in vitro and in an experimental mouse model for Neospora caninum infection. In 4-day proliferation assays, buparvaquone efficiently inhibited N. caninum tachyzoite replication (IC50 = 4.9 nM; IC100 = 100 nM. However, in the long term tachyzoites adapted and resumed proliferation in the presence of 100 nM buparvaquone after 20 days of cultivation. Parasiticidal activity was noted after 9 days of culture in 0.5 µM or 6 days in 1 µM buparvaquone. TEM of N. caninum infected fibroblasts treated with 1 µM buparvaquone showed that the drug acted rather slowly, and ultrastructural changes were evident only after 3–5 days of treatment, including severe alterations in the parasite cytoplasm, changes in the composition of the parasitophorous vacuole matrix and a diminished integrity of the vacuole membrane. Treatment of N. caninum infected mice with buparvaquone (100 mg/kg either by intraperitoneal injection or gavage prevented neosporosis symptoms in 4 out of 6 mice in the intraperitoneally treated group, and in 6 out of 7 mice in the group receiving oral treatment. In the corresponding controls, all 6 mice injected intraperitoneally with corn oil alone died of acute neosporosis, and 4 out of 6 mice died in the orally treated control group. Assessment of infection intensities in the treatment groups showed that, compared to the drug treated groups, the controls showed a significantly higher parasite load in the lungs while cerebral parasite load was higher in the buparvaquone-treated groups. Thus, although buparvaquone did not eliminate the parasites infecting the CNS, the drug represents an interesting lead with the potential to eliminate, or at least diminish, fetal infection during pregnancy.

  9. Buparvaquone is active against Neospora caninum in vitro and in experimentally infected mice

    Science.gov (United States)

    Müller, Joachim; Aguado-Martinez, Adriana; Manser, Vera; Balmer, Vreni; Winzer, Pablo; Ritler, Dominic; Hostettler, Isabel; Arranz-Solís, David; Ortega-Mora, Luis; Hemphill, Andrew

    2015-01-01

    The naphthoquinone buparvaquone is currently the only drug used against theileriosis. Here, the effects of buparvaquone were investigated in vitro and in an experimental mouse model for Neospora caninum infection. In 4-day proliferation assays, buparvaquone efficiently inhibited N. caninum tachyzoite replication (IC50 = 4.9 nM; IC100 = 100 nM). However, in the long term tachyzoites adapted and resumed proliferation in the presence of 100 nM buparvaquone after 20 days of cultivation. Parasiticidal activity was noted after 9 days of culture in 0.5 µM or 6 days in 1 µM buparvaquone. TEM of N. caninum infected fibroblasts treated with 1 µM buparvaquone showed that the drug acted rather slowly, and ultrastructural changes were evident only after 3–5 days of treatment, including severe alterations in the parasite cytoplasm, changes in the composition of the parasitophorous vacuole matrix and a diminished integrity of the vacuole membrane. Treatment of N. caninum infected mice with buparvaquone (100 mg/kg) either by intraperitoneal injection or gavage prevented neosporosis symptoms in 4 out of 6 mice in the intraperitoneally treated group, and in 6 out of 7 mice in the group receiving oral treatment. In the corresponding controls, all 6 mice injected intraperitoneally with corn oil alone died of acute neosporosis, and 4 out of 6 mice died in the orally treated control group. Assessment of infection intensities in the treatment groups showed that, compared to the drug treated groups, the controls showed a significantly higher parasite load in the lungs while cerebral parasite load was higher in the buparvaquone-treated groups. Thus, although buparvaquone did not eliminate the parasites infecting the CNS, the drug represents an interesting lead with the potential to eliminate, or at least diminish, fetal infection during pregnancy. PMID:25941626

  10. Experimental infection of horses with West Nile virus.

    Science.gov (United States)

    Bunning, Michel L; Bowen, Richard A; Cropp, C Bruce; Sullivan, Kevin G; Davis, Brent S; Komar, Nicholas; Godsey, Marvin S; Baker, Dale; Hettler, Danielle L; Holmes, Derek A; Biggerstaff, Brad J; Mitchell, Carl J

    2002-04-01

    A total of 12 horses of different breeds and ages were infected with West Nile virus (WNV) via the bites of infected Aedes albopictus mosquitoes. Half the horses were infected with a viral isolate from the brain of a horse (BC787), and half were infected with an isolate from crow brain (NY99-6625); both were NY99 isolates. Postinfection, uninfected female Ae. albopictus fed on eight of the infected horses. In the first trial, Nt antibody titers reached >1:320, 1:20, 1:160, and 1:80 for horses 1 to 4, respectively. In the second trial, the seven horses with subclinical infections developed Nt antibody titers >1:10 between days 7 and 11 post infection. The highest viremia level in horses fed upon by the recipient mosquitoes was approximately 460 Vero cell PFU/mL. All mosquitoes that fed upon viremic horses were negative for the virus. Horses infected with the NY99 strain of WNV develop low viremia levels of short duration; therefore, infected horses are unlikely to serve as important amplifying hosts for WNV in nature.

  11. Clinico-pathological studies in cattle experimentally infected with Taenia saginata eggs : research communication

    Directory of Open Access Journals (Sweden)

    A. Oryan

    1998-07-01

    Full Text Available Calves 1-2 months old were experimentally infected with eggs of Taenia saginata and clinical and haematological deviations, development and distribution of cysticerci and pathological changes were recorded. The calves infected with 5 000, 10 000 or 50 000 eggs showed an increase in pulse and respiratory rates. The animals that received 50 000 eggs had significantly increased pulse (p<0.05 and respiratory rates (p<0.005. The symptoms were more severe in young, 30-day-old calves infected with 50 000 eggs. Haemoglobin concentration, haematocrit values and red blood cell count decreased, but white blood cell count increased slightly. Lymphocytes and eosinophils also increased up to 88%and 14% (p<0.05, respectively. Most of the cysticerci were not fully formed 1 month post-infection, but at 2 months the cysts were fully mature and at 4 months, some cysts had degenerated. There was no uniformpattern of distribution of cysticerci in the body of infected calves, but the most commonly affected sites were masseter and heart muscles, followed by diaphragm, tongue and other skeletal muscles. The maximum concentration of 8-14 cysticerci per 10 g of tissue was recorded in masseter muscles and heart. The affected parts revealed tissue reactions that included pressure atrophy, necrosis and fibrosis. Microscopically, the lesions comprised infiltration with lymphocytes, plasma cells, eosinophils and macrophages, fibrosis, necrosis and calcification. The tissue reaction was severe in calves infected with 50 000 eggs. The severity of clinical signs, haematological and pathological changes depended mostly on the age of the animals and dose of infection.

  12. The role of IL-12 in experimental Trypanosoma cruzi infection

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    J.S. Silva

    1998-01-01

    Full Text Available Host resistance to Trypanosoma cruzi infection is dependent on both natural and acquired immune responses. During the early acute phase of infection in mice, natural killer (NK cell-derived IFN-g is involved in controlling intracellular parasite replication, mainly through the induction of nitric oxide biosynthesis by activated macrophages. We have shown that IL-12, a powerful inducer of IFN-g production by NK cells, is synthesized soon after trypomastigote-macrophage interaction. The role of IL-12 in the control of T. cruzi infection in vivo was determined by treating infected mice with anti-IL-12 monoclonal antibody (mAb and analyzing both parasitemia and mortality during the acute phase of infection. The anti-IL-12 mAb-treated mice had higher levels of parasitemia and mortality compared to control mice. Also, treatment of infected mice with mAb specific for IFN-g or TNF-a inhibited the protective effect of exogenous IL-12. On the other hand, TGF-ß and IL-10 produced by infected macrophages inhibited the induction and effects of IL-12. Therefore, while IL-12, TNF-a and IFN-g correlate with resistance to T. cruzi infection, TGF-ß and IL-10 promote susceptibility. These results provide support for a role of innate immunity in the control of T. cruzi infection. In addition to its protective role, IL-12 may also be involved in the modulation of T. cruzi-induced myocarditis, since treatment of infected mice with IL-12 or anti-IL-12 mAb leads to an enhanced or decreased inflammatory infiltrate in the heart, respectively. Understanding the role of the cytokines produced during the acute phase of T. cruzi infection and their involvement in protection and pathogenesis would be essential to devise new vaccines or therapies.

  13. Experimental infection of rabbits with bovine viral diarrhoea virus by a natural route of exposure

    Science.gov (United States)

    2014-01-01

    Bovine viral diarrhoea virus (BVDV) is an important pathogen of cattle that can naturally infect a wide range of even-toed ungulates. Non-bovine hosts may represent reservoirs for the virus that have the potential to hamper BVDV eradication programs usually focused on cattle. Rabbits are very abundant in countries such as the United Kingdom or Australia and are often living on or near livestock pastures. Earlier reports indicated that rabbits can propagate BVDV upon intravenous exposure and that natural infection of rabbits with BVDV may occur but experimental proof of infection of rabbits by a natural route is lacking. Therefore, New Zealand White rabbits were exposed to a Scottish BVDV field strain intravenously, oro-nasally and by contaminating their hay with virus. None of the animals showed any clinical signs. However, the lymphoid organs from animals sacrificed at day five after exposure showed histological changes typical of transient infection with pestivirus. Most organ samples and some buffy coat samples were virus positive at day five but saliva samples remained negative. Development of antibodies was observed in all intravenously challenged animals, in all of the nebulised group and in four of six animals exposed to contaminated hay. To our knowledge this is the first report of BVDV propagation in a species other than ruminants or pigs after exposure to the virus by a natural route. However, to assess the role of rabbits as a potential reservoir for BVDV it remains to be determined whether persistent infection caused by intra-uterine infection is possible and whether BVDV is circulating in wild rabbit populations. PMID:24690167

  14. Experimental infection of squirrel monkeys with nipah virus.

    Science.gov (United States)

    Marianneau, Philippe; Guillaume, Vanessa; Wong, Thong; Badmanathan, Munisamy; Looi, Ren Yih; Murri, Severine; Loth, Philippe; Tordo, Noel; Wild, Fabian; Horvat, Branka; Contamin, Hugues

    2010-03-01

    We infected squirrel monkeys (Saimiri sciureus) with Nipah virus to determine the monkeys' suitability for use as primate models in preclinical testing of preventive and therapeutic treatments. Infection of squirrel monkeys through intravenous injection was followed by high death rates associated with acute neurologic and respiratory illness and viral RNA and antigen production.

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

    Directory of Open Access Journals (Sweden)

    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

  16. Preferential infection sites of Cysticercus bovis in cattle experimentally infected with Taenia saginata eggs.

    Science.gov (United States)

    Lopes, Welber D Z; Santos, Thaís R; Soares, Vando E; Nunes, Jorge L N; Mendonça, Rafael P; de Lima, Roberto C A; Sakamoto, Cláudio A M; Costa, Gustavo H N; Thomaz-Soccol, Vanete; Oliveira, Gilson P; Costa, Alvimar J

    2011-02-01

    The preferential sites of infection of Cysticercus bovis were evaluated in the skeletal muscle and entrails of 25 cattle that were experimentally infected with Taenia saginata (2×10(4) eggs). Two other animals were not inoculated (control). Ninety days after inoculation, all the cattle were euthanized. The carcasses were deboned and dissected into 26 anatomical sections (masseter muscles, brain, tongue, esophagus, heart, diaphragm, lungs, liver, kidneys, spleen, top sirloin butt, bottom sirloin butt, outside round, top (inside) round, transversus abdominus, top sirloin cap, strip loin, full tenderloin, eye of round, knuckle, shoulder clod, foreshank, shank, chuck, back ribs, and tail muscles). The dissected tissues were sliced into 5mm sections. From the 25 cattle, 9258 C. bovis (cysticerci) were recovered; 75.02% (6946) of these were recovered from skeletal muscles and 24.98% (2312) from the entrails. A high parasitism level was found in the shoulder clod (12.55%), heart (11.02%), liver (9.48%), masseter muscles (8.51%), chuck (8.25%), strip loin and full tenderloin (7.26%), knuckle (6.63%), and back ribs (5.53%), totaling 69.23% (5738) of all of the detected cysticerci. On the other hand, there was a low C. bovis parasitism level in the brain, spleen, tail muscles, kidneys, esophagus, and diaphragm, representing just 3.9% of the total number of cysticerci. Given these results, we conclude that specific skeletal musculature regions, such as the shoulder blade, chuck, strip loin and full tenderloin, knuckle, back ribs and top round, which are not officially examined in many countries, are effective sites to efficiently screen C. bovis infection. To date, these regions have not been considered as preferential sites of C. bovis infection. Based on our work, however, these regions deserve greater attention from health inspectors because they contained a greater number of Cysticercus than the other regions of carcasses that are parasitized by T. saginata larvae

  17. Recovery of Dengue Viruses from Tissues of Experimentally Infected Rhesus Monkeys

    Science.gov (United States)

    Marchette, Nyven J.; Halstead, Scott B.; Nash, Donald R.; Stenhouse, Andrew C.

    1972-01-01

    A tissue explant culture technique for the recovery of dengue virus from experimentally infected monkey tissue is described and compared with tissue culture assay of tissue triturates and co-cultivation of trypsinized cells in cell cultures. The most efficient technique was one in which minced tissue was explanted in co-culture with dengue virus-susceptible LLC-MK2 monkey kidney cells. This technique shows promise of being useful for detection of virus in autopsy material from fatal dengue hemorrhagic fever cases. PMID:4627963

  18. Helicobacter pylori infection reduces disease severity in an experimental model of multiple sclerosis

    Directory of Open Access Journals (Sweden)

    Katherine eCook

    2015-02-01

    Full Text Available Recent research has demonstrated that infection with the bacterial pathogen Helicobacter pylori is less common amongst patients with multiple sclerosis (MS, an inflammatory demyelinating disease of the central nervous system (CNS. We compared the prevalence of H. pylori amongst MS patients and healthy controls, and also investigated the impact of this infection on an animal model for MS, experimental autoimmune encephalomyelitis (EAE.The H. pylori status of 71 MS patients and 42 healthy controls was determined by serology. Groups of C57BL/6 mice were infected with H. pylori, or given a placebo, prior to inducing EAE. Clinical scores were assessed for all mice, and spleens and spinal cord tissue were harvested. CD4+ T cell subsets were quantified by flow cytometry, and T cell proliferation assays were performed.In MS patients the seroprevalence of H. pylori was half that of healthy controls (p=0.018. Over three independent experiments, prior H. pylori infection had a moderate effect in reducing the severity of EAE (p = 0.012. In line with this, the antigen-specific T cell proliferative responses of infected animals were significantly reduced (p=0.001, and there was a 4-fold reduction in the number of CD4+ cells in the CNS. CD4+ populations in both the CNS and the spleens of infected mice also contained greatly reduced proportions of IFNγ+, IL-17+, T-bet+, and RORγt+ cells, but the proportions of Foxp3+ cells were equivalent. There were no differences in the frequency of splenic CD4+cells expressing markers of apoptosis between infected and uninfected animals.H. pylori was less prevalent amongst MS patients. In mice, the infection exerted some protection against EAE, inhibiting both Th1 and Th17 responses. This could not be explained by the presence of increased numbers of Foxp3+ regulatory T cells, or T cell apoptosis. This is the first direct experimental evidence showing that H. pylori may provide protection against inflammatory demyelination

  19. Experimental fetal and transplacental Neospora infection in the nonhuman primate.

    Science.gov (United States)

    Barr, B C; Conrad, P A; Sverlow, K W; Tarantal, A F; Hendrickx, A G

    1994-08-01

    Neospora is a newly recognized Toxoplasma-like protozoan that causes spontaneous abortion and/or neonatal disease in a wide range of animals. The purpose of this study was to determine the susceptibility of primates to Neospora infection. In experiment 1, two rhesus macaque fetuses were inoculated in utero at gestational day 65 with 1 x 10(6) culture-derived Neospora tachyzoites. A control fetus was given uninfected vehicle. The fetuses were removed by hysterotomy between 13 and 22 days postinoculation. In experiment 2, two pregnant macaques were inoculated intramuscularly and intravenously on gestational day 43 with a total of 1.6 x 10(7) culture-derived tachyzoites. A pregnant control macaque was given uninfected vehicle. The fetuses were removed by hysterotomy between 67 to 70 days postinoculation. Fetal tissues were collected for in vitro parasite isolation, histopathology, and Neospora immunohistochemistry. Fetal blood was examined for Neospora-specific antibody titers using an indirect fluorescent antibody test. Neospora infections were confirmed in all fetuses that received tachyzoites either directly or via transplacental infection. In experiment 1, infected fetuses had reduced amniotic fluid volumes, marked protozoal amnionitis and dermatitis, and a mild multifocal encephalitis. Infected fetuses from experiment 2 had a chronic multifocal necrotizing nonsuppurative meningoencephalitis with microcavitation, that was confined to the cerebrum, and a mild multifocal necrotizing amnionitis. In both experiments, Neospora tachyzoites were detected in association with lesions in fetal tissues by immunohistochemistry, and the parasites were reisolated in vitro. IgG Neospora antibody titers were detected in blood from all infected fetuses, whereas Neospora-specific IgM and IgA titers were found in one and three fetuses, respectively. Results indicate that nonhuman primates are susceptible to transplacental Neospora infection. The fetal lesions after transplacental

  20. 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

  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...... to younger animals, older calves showed significantly less fever and lower TNFa. levels and less virus-specific IFN gamma release. In addition, blood from older animals had more mononuclear cells, more B cells and stronger BRSV-specific IgA and neutralising antibody responses to infection. A strong...

  2. Experimental infection of pregnant gilts with swine hepatitis E virus

    OpenAIRE

    Kasorndorkbua, Chaiyan; Thacker, Brad J.; Halbur, Patrick G.; Guenette, Denis K.; Buitenwerf, Ryan M.; Royer, Ryan L.; Meng, Xiang-Jin

    2003-01-01

    To determine the effect of swine hepatitis E virus (HEV) infection on pregnant gilts, their fetuses, and offspring, 12 gilts were intravenously inoculated with swine HEV. Six gilts, who were not inoculated, served as controls. All inoculated gilts became actively infected and shed HEV in feces, but vertical transmission was not detected in the fetuses. There was no evidence of clinical disease in the gilts or their offspring. Mild multifocal lymphohistiocytic hepatitis was observed in 4 of 12...

  3. Determination of IgG avidity in BALB/c mice experimentally infected with Toxocara canis.

    Science.gov (United States)

    Schoenardie, Elizandra Roselaine; Scaini, Carlos James; Avila, Luciana Farias da Costa de; Sperotto, Rita Leal; Borsuk, Sibele; Felicetti, Cristine Dias Pires; Pepe, Michele; Berne, Maria Elisabeth Aires

    2014-01-01

    Toxocariasis is a zoonotic disease in that IgM titers can remain high for long periods making difficult to determine the stage of the disease. The aim of this study is to investigate the applicability of indirect ELISA, associated with urea, to discriminate between the acute and chronic toxocariasis. IgG avidity was evaluated in 25 BALB/c mice experimentally infected with 1000 Toxocara canis eggs. Blood samples were collected, and sera treated with 6 M urea and assayed by ELISA every two weeks. The percent IgG avidity was determined using the mean absorbance of sera treated with urea, divided by the mean absorbance of untreated sera. In the first 15 days post-inoculation, was observed a low percentage, between 7.25 and 27.5%, IgG avidity, characteristic of an acute infection. After 60 days of infection, all the mice showed between 31.4 and 58% IgG avidity, indicating a chronic infection.

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

    Directory of Open Access Journals (Sweden)

    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

  5. In-State and Interstate Associations Between Gun Shows and Firearm Deaths and Injuries: A Quasi-experimental Study.

    Science.gov (United States)

    Matthay, Ellicott C; Galin, Jessica; Rudolph, Kara E; Farkas, Kriszta; Wintemute, Garen J; Ahern, Jennifer

    2017-12-19

    Gun shows are an important source of firearms, but no adequately powered studies have examined whether they are associated with increases in firearm injuries. To determine whether gun shows are associated with short-term increases in local firearm injuries and whether this association differs by the state in which the gun show is held. Quasi-experimental. California. Persons in California within driving distance of gun shows. Gun shows in California and Nevada between 2005 and 2013 (n = 915 shows) and rates of firearm-related deaths, emergency department visits, and inpatient hospitalizations in California. Compared with the 2 weeks before, postshow firearm injury rates remained stable in regions near California gun shows but increased from 0.67 injuries (95% CI, 0.55 to 0.80 injuries) to 1.14 injuries (CI, 0.97 to 1.30 injuries) per 100 000 persons in regions near Nevada shows. After adjustment for seasonality and clustering, California shows were not associated with increases in local firearm injuries (rate ratio [RR], 0.99 [CI, 0.97 to 1.02]) but Nevada shows were associated with increased injuries in California (RR, 1.69 [CI, 1.16 to 2.45]). The pre-post difference was significantly higher for Nevada shows than California shows (ratio of RRs, 1.70 [CI, 1.17 to 2.47]). The Nevada association was driven by significant increases in firearm injuries from interpersonal violence (RR, 2.23 [CI, 1.01 to 4.89]) but corresponded to a small increase in absolute numbers. Nonfirearm injuries served as a negative control and were not associated with California or Nevada gun shows. Results were robust to sensitivity analyses. Firearm injuries were examined only in California, and gun show occurrence was not randomized. Gun shows in Nevada, but not California, were associated with local, short-term increases in firearm injuries in California. Differing associations for California versus Nevada gun shows may be due to California's stricter firearm regulations. National

  6. An experimental ovine Theileriosis: The effect of Theileria lestoquardi infection on cardiovascular system in sheep.

    Science.gov (United States)

    Yaghfoori, Saeed; Razmi, Gholam Reza; Mohri, Mehrdad; Razavizadeh, Ali Reza Taghavi; Movassaghi, Ahmad Reza

    2016-09-01

    The malignant ovine theileriosis is caused by Theileria lestoquardi, which is highly pathogenic in sheep. Theileriosis involves different organs in ruminants, but the effect of the disease on the cardiovascular system is unclear. To understand the pathogenesis of T. lestoquardi on the cardiovascular system, Baluchi breed sheep were infected with the mentioned parasite by releasing unfed adults of Hyalomma anatolicum anatolicum, which were infected with T. lestoquardi. The infected sheep were clinically examined on days 0, 2, 5, 7, 10, 12, 14, 17, and 21, and the blood samples were collected for biochemical parameters measurement. At termination of the experiment, the infected sheep were euthanized and pathological examinations of heart tissue were conducted. During experimental infection of sheep with T. lestoquardi, activities of cardiac troponin I (cTnI), lactate dehydrogenase, and aspartate aminotransferase, were significantly increased (P˂0.05), while a conspicuous decrease (P˂0.05) was observed in creatine phosphokinase activities. Alterations made in biochemical factors almost coincided with the presence of piroplasm in the blood and schizont in lymph nodes. Maximum and minimum of parasitemia in the sheep stood between 3.3% and 0.28%, respectively. In addition, electrocardiography revealed sinus tachycardia, sinus arrhythmia, sino-atrial block and ST-elevation, atrial premature beat, and alteration in QRS and in T waves' amplitude. Heart histopathological examination showed hyperemia, infiltration of mononuclear inflammatory cells into interstitial tissue, endocarditis, and focal necrosis of cardiac muscle cells. In addition, in one of the sheep, definite occurrence of infarction was observed. The results indicate that T. lestoquardi infection has devastating pathological impacts on the cardiovascular system of sheep. Furthermore, measurement of the cTnI amount is a useful biochemical factor for diagnosis and for better understanding of the severity and

  7. Antigens of worms and eggs showed a differentiated detection of specific IgG according to the time of Schistosoma mansoni infection in mice

    Directory of Open Access Journals (Sweden)

    Rafaella Fortini Queiroz Grenfell

    2012-08-01

    Full Text Available INTRODUCTION: The correlation between the immunological assay and the antibody titer can offer a tool for the experimental analysis of different phases of the disease. METHODS: Two simple immunological assays for Schistosoma mansoni in mice sera samples based on specific IgG detection for worms soluble antigens and eggs soluble antigens were standardized and evaluated in our laboratory. Fifty mice were used in negative and positive groups and the results obtained by enzyme-linked immunosorbent assays (ELISA assays were compared with the number of worms counted and the IgG titers at different times of infection. RESULTS: Data showed that ELISA using adult worm antigens (ELISA-SWAP presented a satisfactory correlation between the absorbance value of IgG titers and the individual number of worms counted after perfusion technique (R²=0.62. In addition, ELISA-SWAP differentially detected positive samples with 30 and 60 days post infection (p=0.011 and 0.003, respectively, whereas ELISA using egg antigens (ELISA-SEA detected samples after 140 days (p=0.03. CONCLUSIONS: These data show that the use of different antigens in immunological methods can be used as potential tools for the analysis of the chronological evolution of S. mansoni infection in murine schistosomiasis. Correlations with human schistosomiasis are discussed.

  8. Antigens of worms and eggs showed a differentiated detection of specific IgG according to the time of Schistosoma mansoni infection in mice.

    Science.gov (United States)

    Grenfell, Rafaella Fortini Queiroz; Martins, Watson Hermann; Silva-Moraes, Vanessa; Barata, Suedali Villas-Boas; Ribeiro, Elizandra Giani; Oliveira, Edward; Coelho, Paulo Marcos Zech

    2012-01-01

    The correlation between the immunological assay and the antibody titer can offer a tool for the experimental analysis of different phases of the disease. Two simple immunological assays for Schistosoma mansoni in mice sera samples based on specific IgG detection for worms soluble antigens and eggs soluble antigens were standardized and evaluated in our laboratory. Fifty mice were used in negative and positive groups and the results obtained by enzyme-linked immunosorbent assays (ELISA) assays were compared with the number of worms counted and the IgG titers at different times of infection. Data showed that ELISA using adult worm antigens (ELISA-SWAP) presented a satisfactory correlation between the absorbance value of IgG titers and the individual number of worms counted after perfusion technique (R²=0.62). In addition, ELISA-SWAP differentially detected positive samples with 30 and 60 days post infection (p=0.011 and 0.003, respectively), whereas ELISA using egg antigens (ELISA-SEA) detected samples after 140 days (p=0.03). These data show that the use of different antigens in immunological methods can be used as potential tools for the analysis of the chronological evolution of S. mansoni infection in murine schistosomiasis. Correlations with human schistosomiasis are discussed.

  9. HIV-infected patients show functionally defective high-density lipoprotein (HDL paralleled with changes in HDL-associated proteins

    Directory of Open Access Journals (Sweden)

    V Estrada

    2012-11-01

    Full Text Available Purpose of the study Epidemiological studies have consistently demonstrated an inverse association between plasma HDL concentrations and cardiovascular risk. Although this cardioprotective role has been mainly attributed to its role in promoting cellular cholesterol efflux, there is an emerging interest in the anti-inflammatory and antioxidant properties of HDL. The aim of the study is to investigate the anti-inflammatory properties of HDL isolated from HIV-infected patients. Methods Cross-sectional study of 113 HIV-infected patients and 70 non-infected control subjects without evident CVD. From each subject, HDL was isolated by ultracentrifugation and its anti-inflammatory status was tested as its ability to inhibit MCP-1-induced migration of the monocytic cell line THP-1 using transwell cell culture chamber inserts with micropore filters of 5 microns pore size. HDL-associated proteins were measured by commercial ELISAs. Results Twenty-three HIV-infected patients were ART-naïve (32±15 years, 66.7% male and ninety were currently on ART (46±11 years, 78.9 % male. Most patients on ART (91.1% had undetectable viral load (<50 copies/mL. When compared to healthy subjects, both naïve and treated HIV-infected patients had lower plasma HDL-cholesterol levels (naïve: 45±12, ART: 50±10, controls: 55±10 mg/dL, p<0.05. HDL isolated from HIV naïve patients showed a significantly reduced anti-inflammatory activity (THP-1 monocyte migration capacity was 203% times higher in HIV patients than in control subjects. The anti-inflammatory activity of HDL from ART-treated HIV-infected patients was significantly improved when compared to naïve patients, although it remained significantly lower than controls (130% THP-1 monocyte migration vs controls. HDL from HIV-infected patients had a decreased concentration of the anti-inflammatory proteins Apo A1 (controls: 2.1±0.3, naïve: 1.4±0.2, ART: 1.6±0.1 mg/ml and LCAT (controls: 0.53±0.09, naïve: 0.34±0

  10. Experimental Hyalohyphomycosis by Purpureocillium lilacinum: Outcome of the Infection in C57BL/6 Murine Models

    Directory of Open Access Journals (Sweden)

    Danielly C. M. de Sequeira

    2017-08-01

    Full Text Available Purpureocillium lilacinum is a filamentous, hyaline fungus considered an emerging pathogen in humans. The aim of our study was to evaluate the outcome of hyalohyphomycosis in C57BL/6 murine models inoculated with two clinical P. lilacinum isolates (S1 and S2. Each isolate was inoculated in mice randomly distributed in immunocompetent (CPT and immunosuppressed (SPS groups. Mice were evaluated at day 7, 21, and 45 after inoculation for histopathological analysis, recovery of fungal cells, and immunological studies. Histological analysis showed scarce conidia-like structures in lung tissue from CPT mice and a lot of fungal cells in SPS mice inoculated with S2 compared to mice inoculated with S1. The maximum recovery of fungal cells was seen in CPT mice inoculated with both isolates at day 7, but with mean significantly higher in those inoculated with S2 isolate. Phenotypical characterization of T cells showed TCD8+ lymphocytes predominance over TCD4+ in immunosuppressed mice infected and control groups. We also observed higher percentages of the central and effector memory/effector phenotype in CPT mice infected with S2 strain, especially in TCD8+ in the initial period of infection. Regulatory T cells showed higher percentages in immunosuppressed, predominantly after the acute phase. Our results showed that the P. lilacinum is a fungus capable to cause damages in competent and immunosuppressed experimental hosts. Furthermore, S2 isolate seems to cause more damage to the experimental host and it was possible to identify different cellular subsets involved in the mice immune response.

  11. Histopathological evaluation of the efficacy of antifungals for experimental Trichosporon bloodstream infection.

    Science.gov (United States)

    Sasai, Daisuke; Okubo, Yoichiro; Ishiwatari, Takao; Sugita, Takashi; Kaneko, Takehiko; Murayama, Somay Yamagata; Shimamura, Tsuyoshi; Shinozaki, Minoru; Hasegawa, Chikako; Mitsuda, Aki; Tochigi, Naobumi; Wakayama, Megumi; Nemoto, Tetsuo; Shibuya, Kazutoshi

    2013-01-01

    The efficacy of polyene macrolides to treat experimental Trichosporon bloodstream infection was evaluated by histopathological examination and viable cell counts in the kidneys of infected mice. Viable cell counts on the 5th day after infection confirmed that liposomal amphotericin B (L-AMB) is a more effective treatment than fluconazole (FLC) for mice infected with an azole-resistant strain of Trichosporon. Histological examination revealed that the administration of L-AMB induced a transformation from acute purulent inflammation caused by both azole-susceptible and -resistant strain infections to a chronic and subsiding form, whereas FLC failed to convert the acute inflammation induced by the azole-resistant strain to a subsiding form. Our results demonstrate that polyene macrolides can be used as an alternative therapy for infection of azole-resistant strains of Trichosporon and that histopathological evaluation is useful for elucidating the pathophysiology of an experimental Trichosporon infection.

  12. Microscopy and Serological Assessment for Heartworm Infection in Cats in Makati, Philippines Showing Clinical Signs of Dirofilariosis

    Directory of Open Access Journals (Sweden)

    A Baticados

    2013-03-01

    Full Text Available Background: The sole published data on feline heartworm infection in the Philippines was reported four decades ago. The study therefore endeavoured to assess and provide an update on the current status of heartworm infection in domesticated feline species using serologic and parasitological examina­tion methods.Methods: A total of 46 males and 54 females cats showing clinical signs of dirofilariosis from Makati City, Philippines were subjected to two antigen-based test kits and a microfilaria concentration method.Results: The most commonly observed clinical sign was coughing while exercise intolerance was seldom seen. Age groups ranging from 1 to 4 years old exhibited majority of the clinical signs whereas the 8.1 to 12 years category had the least. The results from the different detection methods employed revealed that none of the animals were positive for circulating microfilaria and no detect­able levels of heartworm antigens were obtained.Conclusion: The presence of associated clinical signs is not an outright indicator of feline dirofilariosis and may be indicative of the rarity of heartworm infection in cats in Makati, Philippines.

  13. Trypanosoma evansi experimental infection in the South American coati (Nasua nasua): clinical, parasitological and humoral immune response.

    Science.gov (United States)

    Herrera, H M; Aquino, L P; Menezes, R F; Marques, L C; Moraes, M A; Werther, K; Machado, R Z

    2001-12-13

    The course of Trypanosoma evansi infection in coatis (Carnivora, Procionidae) was followed for 262 days. Parasites were detected in all infected animals from day 2 post infection until the end of the study. No correlation between temperature and parasitemia was observed. Animals of the infected group demonstrated depression, weakness, lethargy and pale mucous membranes. Indirect fluorescent antibody tests detected anti-T. evansi antibodies within 7 to 14 days post infection and showed high levels until the end of the experimental period. The persistent parasitemia in coati and their relative tolerance to clinical signs suggested that this species develops a chronic disease and plays an important role in the epidemiology of trypanosomosis due to T. evansi in enzootic regions.

  14. [Experimental and natural infection with the enzootic leukosis virus of cattle].

    Science.gov (United States)

    Hofírek, B; Horín, P; Granátová, M; Machatková, M; Franz, J; Svoboda, I; Blecha, J

    1986-03-01

    A trial was performed with heifers at the age of six to seven months. The animals were experimentally infected with the lymphocytes of a virus-productive donor. Infection was produced in all the nine cases, as demonstrated by means of the positive syncytial test. As indicated by the results of the trial, the antibodies to the enzootic bovine leucosis virus (BLV) were produced soon after experimental infection. A high sensitivity of the serum-neutralization test and the ELISA method was demonstrated in this connection: by these methods, the antibodies were identified already two to three weeks after experimental infection whereas by the immunodiffusion test they could be detected only after five weeks. Twenty-four animals were exposed to natural contact infection. Within 270 days of the trial, the disease after contact was recorded only in one heifer out of the four that were in close contact with the experimentally infected animals. In this case, as compared with experimental infection, the antibodies were produced much later--after 85 to 93 days. Leucosis was recorded in none of the remaining animals. The reasons why such a favourable result was obtained were the thorough disinfection of the stables after blood collections and the strict observance of the aseptic conditions. The results of experimental infection in three cows were identical with those obtained in young cattle. In the experimentally infected dairy cows, antibodies in milk were determined by the ELISA method. As found, in milk the antibodies to BLV appear two to three weeks later than they do in serum. The ELISA method of BLV antibody detection can be used for the identification of infected animals in herds where enzootic bovine leucosis occurs.

  15. Experimental therapeutic studies of Solanum aculeastrum Dunal. on Leishmania major infection in BALB/c mice.

    Science.gov (United States)

    Laban, Linet T; Anjili, Christopher O; Mutiso, Joshua M; Ingonga, Johnstone; Kiige, Samuel G; Ngedzo, Mgala M; Gicheru, Michael M

    2015-01-01

    Solanum acueastrum Dunal. has been shown to have some chemotherapeutic value. Leaf and berry water and methanol compounds of S. acueastrum were evaluated for possible antileishmanial activity In vivo on BALB/c mice and in vitro against Leishmania major promastigotes, amastigotes and vero cells. Dry S. aculeastrum berry and leaf material were extracted in methanol and water. L. major parasites were exposed to different concentrations of S. aculeastrum fruit and leaf compounds and the IC50 on the promastigotes, percentage of infection rate of macrophages by amastigotes and the toxicological effect on vero cells were determined. BALB/c mice were infected subcutaneously with 1×10(6) promastigotes and kept for four weeks to allow for disease establishment. Infected mice were treated with fruit and leaf methanolic and water compounds, amphotericin B (AmB), and sterile phosphate buffered saline (PBS). Fruit methanol compound was most effective in inhibiting the growth of promastigotes with IC5078.62 μg/ml. Fruit water compound showed the best activity in inhibiting infection of macrophages by amastigotes. Fruit methanol compound was more toxic at Ld50=8.06 mg/ml to vero cells than amphotericin B. Analysis of variance computation indicated statistically significant difference in lesion sizes between experimental and control mice groups (P=0.0001). Splenic impression smears ANOVA indicated a highly significant difference in parasitic numbers between the experimental and the control groups (P=0.0001). The results demonstrate that compounds from S. aculeastrum have potential anti-leishmanial activities and the medicinal use of the plant poses considerable toxicity against dividing vero cells.

  16. 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.

  17. Using experimental human influenza infections to validate a viral dynamic model and the implications for prediction.

    Science.gov (United States)

    Chen, S C; You, S H; Liu, C Y; Chio, C P; Liao, C M

    2012-09-01

    The aim of this work was to use experimental infection data of human influenza to assess a simple viral dynamics model in epithelial cells and better understand the underlying complex factors governing the infection process. The developed study model expands on previous reports of a target cell-limited model with delayed virus production. Data from 10 published experimental infection studies of human influenza was used to validate the model. Our results elucidate, mechanistically, the associations between epithelial cells, human immune responses, and viral titres and were supported by the experimental infection data. We report that the maximum total number of free virions following infection is 10(3)-fold higher than the initial introduced titre. Our results indicated that the infection rates of unprotected epithelial cells probably play an important role in affecting viral dynamics. By simulating an advanced model of viral dynamics and applying it to experimental infection data of human influenza, we obtained important estimates of the infection rate. This work provides epidemiologically meaningful results, meriting further efforts to understand the causes and consequences of influenza A infection.

  18. Immunity to Lutzomyia whitmani Saliva Protects against Experimental Leishmania braziliensis Infection.

    Science.gov (United States)

    Gomes, Regis; Cavalcanti, Katrine; Teixeira, Clarissa; Carvalho, Augusto M; Mattos, Paulo S; Cristal, Juqueline R; Muniz, Aline C; Miranda, José Carlos; de Oliveira, Camila I; Barral, Aldina

    2016-11-01

    Previous works showed that immunization with saliva from Lutzomyia intermedia, a vector of Leishmania braziliensis, does not protect against experimental infection. However, L. braziliensis is also transmitted by Lutzomyia whitmani, a sand fly species closely related to Lu. intermedia. Herein we describe the immune response following immunization with Lu. whitmani saliva and the outcome of this response after L. braziliensis infection. BALB/c mice immunized with Lu. whitmani saliva developed robust humoral and cellular immune responses, the latter characterized by an intense cellular infiltrate and production of IFN-γ and IL-10, by both CD4+ and CD8+ cells. Mice immunized as above and challenged with L. braziliensis plus Lu. whitmani saliva displayed significantly smaller lesions and parasite load at the challenge site. This protection was associated with a higher (p<0.05) IFN-γ production in response to SLA stimulation. Long-term persisting immunity was also detected in mice immunized with Lu. whitmani saliva. Furthermore, individuals residing in an endemic area for cutaneous leishmaniasis (CL) presented antibody responses to Lu. whitmani saliva. However CL patients, with active lesions, displayed a lower humoral response to Lu. whitmani saliva compared to individuals with subclinical Leishmania infection. Pre-exposure to Lu. whitmani saliva induces protection against L. braziliensis in a murine model. We also show that Lu. whitmani salivary proteins are immunogenic in naturally exposed individuals. Our results reinforce the importance of investigating the immunomodulatory effect of saliva from different species of closely related sand flies.

  19. Pre-infection frequencies of equine herpesvirus-1 specific, cytotoxic T lymphocytes correlate with protection against abortion following experimental infection of pregnant mares.

    Science.gov (United States)

    Kydd, J H; Wattrang, E; Hannant, D

    2003-12-15

    In general, vaccines containing inactivated equine herpesvirus-1 (EHV-1) fail to prevent abortion in pregnant mares following infection with a virulent strain of EHV-1. We have tested the hypothesis that resistance to EHV-1-induced abortion in pregnant mares is associated with high frequencies of EHV-1 specific, major histocompatibility complex (MHC) class I-restricted, cytotoxic T lymphocytes (CTL) in the circulation. To test this theory, three groups of pregnant mares were assembled with varying backgrounds of infection or vaccination in an attempt to mimic the immune status of the general population. Group 1 mares (n=9) were untreated controls selected at random. Group 2 mares (n=5) were vaccinated three times intramuscularly with inactivated EHV-1. Group 3 mares (n=3) had been infected with EHV-1 on four previous occasions. The frequency of CTL in blood leucocytes was measured by limiting dilution analysis at three time points; at the beginning of pregnancy (approximately 28 weeks before infection) in the Group 2 and Group 3 mares (4-7 weeks of gestation) (Group 1 was unavailable for sampling) and then 2 weeks before (30-40 weeks of gestation) and 3 weeks after experimental infection in all the mares. Serum samples were collected to monitor complement fixing (CF) antibody titres. Mares in all three groups were infected experimentally with EHV-1 strain Ab4/8 by the intranasal route after which they were monitored clinically to determine the outcome of pregnancy and samples were collected to determine the duration of nasopharyngeal shedding and cell-associated viraemia. The untreated control mares showed low pre-infection CTL. After experimental infection, they all seroconverted, aborted and demonstrated expected clinical and virological signs. Some vaccinated mares (3/5) had elevated titres of CF antibody prior to their first vaccination. All the vaccinated mares seroconverted after vaccination and exhibited higher CTL frequencies than controls before infection

  20. Cardiac plexus of dogs experimentally infected with Trypanosoma cruzi: inflammatory lesions and quantitative studies

    Directory of Open Access Journals (Sweden)

    Marcelo V. Caliari

    1995-03-01

    Full Text Available Qualitative and quantitative aspects of the superficial and profound cardiac plexus of dogs experimentally infected with Be-62 and Be-78 strains of Trypanosoma cruzi were studied. Animals were autopsied in the acute phase of infection. The inflammatory process, lesions and number of parasites were more intense and frequent in animals infected with the Be-78 strain than in those infected with Be-62. Despite this, no statistically significant differences could be found between the number of neuron bodies in the ganglia of infected and control dogs.

  1. Transcriptome-wide characterization of human cytomegalovirus in natural infection and experimental latency.

    Science.gov (United States)

    Cheng, Shu; Caviness, Katie; Buehler, Jason; Smithey, Megan; Nikolich-Žugich, Janko; Goodrum, Felicia

    2017-11-20

    The transcriptional program associated with herpesvirus latency and the viral genes regulating entry into and exit from latency are poorly understood and controversial. Here, we developed and validated a targeted enrichment platform and conducted large-scale transcriptome analyses of human cytomegalovirus (HCMV) infection. We used both an experimental hematopoietic cell model of latency and cells from naturally infected, healthy human subjects (clinical) to define the breadth of viral genes expressed. The viral transcriptome derived from experimental infection was highly correlated with that from clinical infection, validating our experimental latency model. These transcriptomes revealed a broader profile of gene expression during infection in hematopoietic cells than previously appreciated. Further, using recombinant viruses that establish a nonreactivating, latent-like or a replicative infection in CD34+ hematopoietic progenitor cells, we defined classes of low to moderately expressed genes that are differentially regulated in latent vs. replicative states of infection. Most of these genes have yet to be studied in depth. By contrast, genes that were highly expressed, were expressed similarly in both latent and replicative infection. From these findings, a model emerges whereby low or moderately expressed genes may have the greatest impact on regulating the switch between viral latency and replication. The core set of viral genes expressed in natural infection and differentially regulated depending on the pattern of infection provides insight into the HCMV transcriptome associated with latency in the host and a resource for investigating virus-host interactions underlying persistence.

  2. First attempt to produce experimental Campylobacter concisus infection in mice

    DEFF Research Database (Denmark)

    Aabenhus, R.; Stenram, U.; Andersen, L.P.

    2008-01-01

    AIM: To infect mice with atypical Campylobacter concisus (C. concisus) for the first time. METHODS: Three separate experiments were conducted in order to screen the ability of five clinical C. concisus isolates of intestinal origin and the ATCC 33237 type strain of oral origin to colonize...

  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...

  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. 0f chemotherapy in goats experimentally infected with

    African Journals Online (AJOL)

    'Y58' stock. The goats were monitored serologically by using antigen-ELISA and Antibody-ELISA before and after Berenil treatment for a period lasting about sixty two days. The mean prepatent period before trypanosomes were detected in their bloodstreams was five days post-infection; circulating antigens and antibodies ...

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

    African Journals Online (AJOL)

    Salmonella enterica serovar Enteritidis is a food borne pathogen of humans causing food-poisoning and sometimes deaths. In order to control egg-borne transmission of Salmonella Enteritidis to humans, prompt and accurate detection of infected poultry flocks is essential. This paper examined the effects of challenge dose ...

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

    African Journals Online (AJOL)

    concentration, RBC counts and PCV values between exotic and indigenous animals but these physiological values were not recorded for different species and breeds of indigenous animals in Ethiopia. Information is also lacking about the effects of GI nematodes infection on these physiological parameters. (Bekele Tafesse ...

  8. Effects of experimental Neisseria meningitis W135 infection on ...

    African Journals Online (AJOL)

    This study investigated the effects of Neisseria menigitidis W135 infection via intraperitoneal route on plasma free tryptophan concentration, brain serotonin and 5-hydroxyindole acetic acid (5-HIAA) levels in albino mice fed normal and tryptophan-enriched diets. The kinetics of appearance of viable bacteria in the blood, ...

  9. Early stage leucocytosis in Nigerian pigs experimentally infected ...

    African Journals Online (AJOL)

    Sequential leukocyte changes associated with early phase of Trypanosoma brucei infection were investigated in indigenous Nigerian pigs. This was with the view to providing further hematological basis for effective chemotherapy of natural porcine trypanosomosis and to assessing the possible roles of leukocytes in ...

  10. New evidence showing that the destruction of gut bacteria by antibiotic treatment could increase the honey bee's vulnerability to Nosema infection.

    Directory of Open Access Journals (Sweden)

    Jiang Hong Li

    Full Text Available It has become increasingly clear that gut bacteria play vital roles in the development, nutrition, immunity, and overall fitness of their eukaryotic hosts. We conducted the present study to investigate the effects of gut microbiota disruption on the honey bee's immune responses to infection by the microsporidian parasite Nosema ceranae. Newly emerged adult workers were collected and divided into four groups: Group I-no treatment; Group II-inoculated with N. ceranae, Group III-antibiotic treatment, and Group IV-antibiotic treatment after inoculation with N. ceranae. Our study showed that Nosema infection did not cause obvious disruption of the gut bacterial community as there was no significant difference in the density and composition of gut bacteria between Group I and Group II. However, the elimination of gut bacteria by antibiotic (Groups III and IV negatively impacted the functioning of the honey bees' immune system as evidenced by the expression of genes encoding antimicrobial peptides abaecin, defensin1, and hymenoptaecin that showed the following ranking: Group I > Group II > Group III > Group IV. In addition, significantly higher Nosema levels were observed in Group IV than in Group II, suggesting that eliminating gut bacteria weakened immune function and made honey bees more susceptible to Nosema infection. Based on Group IV having displayed the highest mortality rate among the four experimental groups indicates that antibiotic treatment in combination with stress, associated with Nosema infection, significantly and negatively impacts honey bee survival. The present study adds new evidence that antibiotic treatment not only leads to the complex problem of antibiotic resistance but can impact honey bee disease resistance. Further studies aimed at specific components of the gut bacterial community will provide new insights into the roles of specific bacteria and possibly new approaches to improving bee health.

  11. 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

  12. Recrudescent Campylobacter jejuni infection in an immunocompetent adult following experimental infection with a well-characterized organism.

    Science.gov (United States)

    Baqar, Shahida; Tribble, David R; Carmolli, Marya; Sadigh, Katrin; Poly, Frederic; Porter, Chad; Larsson, Catherine J; Pierce, Kristen K; Guerry, Patricia; Darsley, Michael; Kirkpatrick, Beth

    2010-01-01

    The recrudescence of infection with Campylobacter jejuni after appropriate antibiotic treatment has not been previously reported in an immunocompetent adult. We present the complete clinical, microbiologic, and immunologic evaluation of a closely monitored healthy male with recrudescent C. jejuni infection occurring in the absence of immunodeficiency following experimental infection with a well-characterized strain. After antibiotic treatment, the initial infection was clinically cleared and microbiologically undetectable. Subsequently, two episodes of recrudescence occurred, with no change in in vitro antibiotic sensitivity being detected. The immune responses of the individual were compared to those of other participants in the experimental infection study: innate immune responses, including fecal cytokines and C-reactive protein, were intact; however, measures of Campylobacter-specific adaptive immune responses were absent, including serum antibodies, antibody-secreting cells, and in vitro gamma interferon responses. No primary or secondary immunodeficiency was identified. Recrudescent Campylobacter infections after treatment may be more common than has previously been appreciated. This work adds to our understanding of the human immune response to natural Campylobacter infection and reiterates the importance of pathogen-specific adaptive immune responses to this globally important pathogen.

  13. Recrudescent Campylobacter jejuni Infection in an Immunocompetent Adult following Experimental Infection with a Well-Characterized Organism▿ †

    Science.gov (United States)

    Baqar, Shahida; Tribble, David R.; Carmolli, Marya; Sadigh, Katrin; Poly, Frederic; Porter, Chad; Larsson, Catherine J.; Pierce, Kristen K.; Guerry, Patricia; Darsley, Michael; Kirkpatrick, Beth

    2010-01-01

    The recrudescence of infection with Campylobacter jejuni after appropriate antibiotic treatment has not been previously reported in an immunocompetent adult. We present the complete clinical, microbiologic, and immunologic evaluation of a closely monitored healthy male with recrudescent C. jejuni infection occurring in the absence of immunodeficiency following experimental infection with a well-characterized strain. After antibiotic treatment, the initial infection was clinically cleared and microbiologically undetectable. Subsequently, two episodes of recrudescence occurred, with no change in in vitro antibiotic sensitivity being detected. The immune responses of the individual were compared to those of other participants in the experimental infection study: innate immune responses, including fecal cytokines and C-reactive protein, were intact; however, measures of Campylobacter-specific adaptive immune responses were absent, including serum antibodies, antibody-secreting cells, and in vitro gamma interferon responses. No primary or secondary immunodeficiency was identified. Recrudescent Campylobacter infections after treatment may be more common than has previously been appreciated. This work adds to our understanding of the human immune response to natural Campylobacter infection and reiterates the importance of pathogen-specific adaptive immune responses to this globally important pathogen. PMID:19923572

  14. Transcriptional analysis of immune-relevant genes in the mucus of Labeo rohita, experimentally infected with Argulus siamensis.

    Science.gov (United States)

    Parida, Sonali; Mohapatra, Amruta; Kar, Banya; Mohanty, Jyotirmaya; Sahoo, Pramoda Kumar

    2018-03-26

    The knowledge of mucosa-associated molecular events that occur during infections is scarce despite the well-established importance of mucus in fish immunity. Using qRT-PCR, we analyzed the immune gene expression patterns in mucus of Labeo rohita experimentally infected with an ectoparasite Argulus siamensis. Mucus samples were collected at 0 h, 12 h, 24 h, 3 d, 7 d, 15 d, and 30 d post challenge of L. rohita with metanauplii of A. siamensis. All interleukins studied herein (IL 6, IL 15, and IL 1β) showed significant upregulation of expression levels in mucus of A. siamensis-infected fish compared to control samples. Further, the expression levels of molecules involved in pathogen recognition, toll like receptor 22, and pathogen presentation, β2 microglobulin, were found to be significantly upregulated in experimental samples until 7 d post challenge compared to control samples. The upregulated expression of lysozyme G at all time points post infection indicated the early activation of acute phase responses in mucus of infected L. rohita. Moreover, the expression levels of natural killer cell enhancing factor B were found to be higher in infected fish than they were in the control fish. The early upregulation of the immune genes observed herein reinforces the role of mucus as the first line of defense against pathogenic assault; furthermore, it expands our understanding of mucosal-immune responses to A. siamensis infection, which can aid development of immunological interventions.

  15. Longevity and composition of cellular immune responses following experimental Plasmodium falciparum malaria infection in humans.

    Directory of Open Access Journals (Sweden)

    Anne C Teirlinck

    2011-12-01

    Full Text Available Cellular responses to Plasmodium falciparum parasites, in particular interferon-gamma (IFNγ production, play an important role in anti-malarial immunity. However, clinical immunity to malaria develops slowly amongst naturally exposed populations, the dynamics of cellular responses in relation to exposure are difficult to study and data about the persistence of such responses are controversial. Here we assess the longevity and composition of cellular immune responses following experimental malaria infection in human volunteers. We conducted a longitudinal study of cellular immunological responses to sporozoites (PfSpz and asexual blood-stage (PfRBC malaria parasites in naïve human volunteers undergoing single (n = 5 or multiple (n = 10 experimental P. falciparum infections under highly controlled conditions. IFNγ and interleukin-2 (IL-2 responses following in vitro re-stimulation were measured by flow-cytometry prior to, during and more than one year post infection. We show that cellular responses to both PfSpz and PfRBC are induced and remain almost undiminished up to 14 months after even a single malaria episode. Remarkably, not only 'adaptive' but also 'innate' lymphocyte subsets contribute to the increased IFNγ response, including αβT cells, γδT cells and NK cells. Furthermore, results from depletion and autologous recombination experiments of lymphocyte subsets suggest that immunological memory for PfRBC is carried within both the αβT cells and γδT compartments. Indeed, the majority of cytokine producing T lymphocytes express an CD45RO(+ CD62L(- effector memory (EM phenotype both early and late post infection. Finally, we demonstrate that malaria infection induces and maintains polyfunctional (IFNγ(+IL-2(+ EM responses against both PfRBC and PfSpz, previously found to be associated with protection. These data demonstrate that cellular responses can be readily induced and are long-lived following infection with P

  16. Experimental treatment with sodium stibogluconate of hamsters infected with Leishmania (Leishmania) chagasi and Leishmania (Leishmania) amazonensis

    OpenAIRE

    Elizabeth M. de Figueiredo; Silva,Jaime Costa e; Brazil,Reginaldo P

    1999-01-01

    The present paper reports the experimental treatment of hamsters infected with Leishmania chagasi and Leishmania amazonensis with sodium stibogluconate (20mg/kg/day x 20 days). Only with L. chagasi did the treatment result in the complete elimination of parasites from the spleen. However, no parasitological cure was achieved in hamsters infected with L. amazonensis.O presente trabalho é um relato do tratamento experimental de hamsters infectado com Leishmania chagasi e Leishmania amazonensis ...

  17. Plant essential oils against Aeromonas hydrophila: in vitro activity and their use in experimentally infected fish.

    Science.gov (United States)

    Sutili, F J; Silva, L de Lima; Gressler, L T; Gressler, L T; Battisti, E K; Heinzmann, B M; de Vargas, A C; Baldisserotto, B

    2015-07-01

    The aims of this study were to investigate the in vitro antibacterial activity of the essential oils (EOs) of Hesperozygis ringens (HREO), popularly known as 'espanta-pulga' and two different species of basil, Ocimum gratissimum (OGEO) and Ocimum americanum (OAEO), as well as, the potential of these products to be used in silver catfish (Rhamdia quelen) infected with Aeromonas hydrophila. OGEO and HREO showed better antibacterial activity in vitro. Subinhibitory concentrations of all EOs inhibited haemolysis caused by Aer. hydrophila in fish erythrocytes (100% reduction for OAEO at 100 μg ml(-1) and more than 90% for HREO and OGEO at 150 μg ml(-1) ). However, OAEO and HREO showed the best survival results (75 and 70% respectively) after their use as treatment (therapeutic baths-1 h daily/5 days) in silver catfish experimentally infected with Aer. hydrophila. A second in vivo assay using healthy fish was conducted to verify the potential of the EOs (preventive baths-1 h daily/5 days) to promote fish survival. Fish exposed to HREO and OAEO and their diluent (ethanol) showed significant lower haematocrit values and higher complement system activity compared to control. Plasma cortisol level was significantly higher in the groups exposed to both EOs. There was no significant difference in survival of silver catfish challenged with Aer. hydrophila after preventive baths with HREO, OAEO and control group. All tested EOs showed in vitro antibacterial properties against Aer. hydrophila and HREO and OAEO showed potential to be used in the treatment of infected fish. These products can be used in aquaculture as therapeutic and prophylactic agents against fish pathogens, with antimicrobial and/or immunostimulant properties. © 2015 The Society for Applied Microbiology.

  18. 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

  19. 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 ...... could be identified in tissue sections by immunostaining. Immunohistochemically, B, licheniformis was demonstrated in hepatic and pulmonic macrophages, and from some animals the bacteria were also reisolated....

  20. 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.

  1. Technetium-99m stannous pyrophosphate imaging of experimental infective endocarditis. [Rabbits

    Energy Technology Data Exchange (ETDEWEB)

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

    1978-07-01

    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.

  2. Efficacy of toltrazuril and ponazuril against experimental Neospora caninum infection in mice.

    Science.gov (United States)

    Gottstein, B; Eperon, S; Dai, W J; Cannas, A; Hemphill, A; Greif, G

    2001-01-01

    Neosporosis is a disease affecting predominantly fetal development in cattle and dog hosts; and it may cause neuromuscular disfunction in infected newborn calves and pups. Predispositions--including, e.g. transient immunosuppression during pregnancy--may result in an increased dissemination of the parasite within the host or its offspring. Chemotherapeutic treatment of neosporosis may be an issue, provided that an appropriate drug is made available. In this respect, we describe the use of a mouse model for the evaluation of toltrazuril and ponazuril medication as a means of preventing parasite dissemination and subsequent formation of cerebral lesions. Toltrazuril- and ponazuril-treated mice were experimentally infected intraperitoneally (i.p.) with 2 x 10(6) Neospora caninum tachyzoites. The infection was monitored at three levels: clinically, by assessing symptoms, histologically, by assessing the occurrence of cerebral lesions and parasites by immunohistochemistry, and on the molecular level, by detection of parasite DNA using PCR. Chemotherapy using either toltrazuril or ponazuril, both applied in a drinking-water formulation (20 mg toltrazuril or ponazuril kg(-1) body weight day(-1)) completely prevented the formation of cerebral lesions in all treated animals, as assessed by immunohistochemistry. PCR analyses of these treated animals showed that DNA-detectability was reduced by 91% and 90% upon toltrazuril and ponazuril medication, respectively.

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

    Directory of Open Access Journals (Sweden)

    Adriano Fernando Araújo

    2014-01-01

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

  4. Antischistosomal activity of hederacochiside C against Schistosoma japonicum harbored in experimentally infected animals.

    Science.gov (United States)

    Kang, Nai-Xin; Zhu, Yuan-Jian; Zhao, Jian-Ping; Zhu, Wei-Feng; Liu, Yan-Li; Xu, Qiong-Ming; Zhuge, Hong-Xiang; Khan, Ikhlas A; Yang, Shi-Lin

    2017-04-01

    The present study was undertaken to investigate whether hederacochiside C (HSC) possesses antischistosomal effects and anti-inflammatory response activities in Schistosoma japonicum-infected mice. Different concentrations of HSC were administrated to the mice infected by schistosomula or adult worm by intravenous injection twice a day for five consecutive days. The total worm burden, female worm burden, and the egg burden in liver of mice treated with 400 mg/kg HSC were fewer than those in non-treated ones. Murine immune responses following HSC treatment were investigated using enzyme-linked immunosorbent assays (ELISA). Our results indicated that 200 mg/kg HSC could reduce the expression of IgG, tumor necrosis factor (TNF)-α, interleukin (IL)-4 and IL-17 in comparison to infected group, exhibiting best immunomodulatory effects. In addition, scanning electron microscopical examination revealed that male worms treated with HSC lost their normal surface architecture since its surface showed extensive swelling, erosion, and peeling in tegumental regions. Remarkable amelioration was noticed in histopathological investigations, and 200 mg/kg HSC treatment could reduce the size of granulomatous inflammatory infiltrations in the liver which was reflected in nearly normalization of liver architecture. These results suggested that HSC had potential antischistosomal activity and provided a basis for subsequent experimental.

  5. 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.

  6. Experimental infection of the rabbit tick, Haemaphysalis leporispalustris, with the bacterium Rickettsia rickettsii, and comparative biology of infected and uninfected tick lineages.

    Science.gov (United States)

    Freitas, Luciana Helena T; Faccini, João Luiz H; Labruna, Marcelo B

    2009-04-01

    The present study consisted of two experiments that evaluated experimental infections of Haemaphysalis leporispalustris ticks by a Brazilian strain of Rickettsia rickettsii, and their effect on tick biology. In experiment I, ticks were exposed to R. rickettsii during the larval, nymphal or adult stages by feeding on rabbits (Oryctolagus cuniculus) needle-inoculated with R. rickettsii, and thereafter reared on uninfected rabbits for the entire next tick generation. Regardless of the tick stage that acquired the infection, all subsequent tick stages were shown to be infected by PCR (infection rates varying from 1.3 to 41.7%), and were able to transmit R. rickettsii to uninfected rabbits, as demonstrated by rabbit seroconversion, guinea pig inoculation with rabbit blood, and PCR on rabbit blood. In Experiment II, ticks were exposed to R. rickettsii during the larval stage by feeding on rabbits co-infested with R. rickettsii-infected adult ticks, and thereafter reared on uninfected rabbits until the next generation of larvae. Again, all subsequent tick stages were shown to be infected by PCR (infection rates varying from 3.0 to 40.0%), and were able to transmit R. rickettsii to uninfected rabbits. Thus, it was demonstrated that larvae, nymphs, and adults of H. leporispalustris were able to acquire and maintain the R. rickettsii infection by transstadial and transovarial transmissions within the tick population, with active transmission of the bacterium to susceptible rabbits by all parasitic stages. Analyses of biological parameters of uninfected and R. rickettsii-infected tick lineages were performed in order to evaluate possible deleterious effects of R. rickettsii to the infected tick lineages. Surprisingly, all but one of the four R. rickettsii-experimental groups of the present study showed overall better biological performance than their sibling uninfected control ticks. Results of the present study showed that H. leporispalustris could support infection by a

  7. 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.

  8. 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...... 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...

  9. Regulatory T cell induction during Plasmodium chabaudi infection modifies the clinical course of experimental autoimmune encephalomyelitis.

    Directory of Open Access Journals (Sweden)

    Alessandro S Farias

    Full Text Available BACKGROUND: Experimental autoimmune encephalomyelitis (EAE is used as an animal model for human multiple sclerosis (MS, which is an inflammatory demyelinating autoimmune disease of the central nervous system characterized by activation of Th1 and/or Th17 cells. Human autoimmune diseases can be either exacerbated or suppressed by infectious agents. Recent studies have shown that regulatory T cells play a crucial role in the escape mechanism of Plasmodium spp. both in humans and in experimental models. These cells suppress the Th1 response against the parasite and prevent its elimination. Regulatory T cells have been largely associated with protection or amelioration in several autoimmune diseases, mainly by their capacity to suppress proinflammatory response. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we verified that CD4(+CD25(+ regulatory T cells (T regs generated during malaria infection (6 days after EAE induction interfere with the evolution of EAE. We observed a positive correlation between the reduction of EAE clinical symptoms and an increase of parasitemia levels. Suppression of the disease was also accompanied by a decrease in the expression of IL-17 and IFN-γ and increases in the expression of IL-10 and TGF-β1 relative to EAE control mice. The adoptive transfer of CD4(+CD25(+ cells from P. chabaudi-infected mice reduced the clinical evolution of EAE, confirming the role of these T regs. CONCLUSIONS/SIGNIFICANCE: These data corroborate previous findings showing that infections interfere with the prevalence and evolution of autoimmune diseases by inducing regulatory T cells, which regulate EAE in an apparently non-specific manner.

  10. Effects of Non-Susceptible Hosts on the Infection with Trypanosoma cruzi of the Vector Triatoma infestans: an Experimental Model

    Directory of Open Access Journals (Sweden)

    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 raccoons (Procyon lotor) with West Nile virus.

    Science.gov (United States)

    Root, J Jeffrey; Bentler, Kevin T; Nemeth, Nicole M; Gidlewski, Thomas; Spraker, Terry R; Franklin, Alan B

    2010-10-01

    To characterize the responses of raccoons to West Nile virus (WNV) infection, we subcutaneously exposed them to WNV. Moderately high viremia titers (≤ 10(4.6) plaque forming units [PFU]/mL of serum) were noted in select individuals; however, peak viremia titers were variable and viremia was detectable in some individuals as late as 10 days post-inoculation (DPI). In addition, fecal shedding was prolonged in some animals (e.g., between 6 and 13 DPI in one individual), with up to 10(5.0) PFU/fecal swab detected. West Nile virus was not detected in tissues collected on 10 or 16 DPI, and no histologic lesions attributable to WNV infection were observed. Overall, viremia profiles suggest that raccoons are unlikely to be important WNV amplifying hosts. However, this species may occasionally shed significant quantities of virus in feces. Considering their behavioral ecology, including repeated use of same-site latrines, high levels of fecal shedding could potentially lead to interspecies fecal-oral WNV transmission.

  12. Natural and experimental evidence of viscerotropic infection caused by Leishmania tropica from North Sinai, Egypt.

    Science.gov (United States)

    Doha, Said A; Shehata, Magdi G; Fahmy, Adel R; Samy, Abdallah M

    2014-08-01

    Cutaneous leishmaniasis (CL) is a neglected clinical form that is quite prevalent in Eastern North parts of the country in Sinai Peninsula. Leishmania tropica was identified by previous reports as the causative agent responsible for viscerotropic infections in-patients and experimental animals. Here, we reported the viscerotropic infections from naturally infected rodent Gerbillus pyramidum floweri collected from North-Sinai. Footpad and tail lesions, spleenomegaly, and malformed dark-colored spleen were the characteristic CL symptoms. The spleen of the rodent found positive to amastigote impression smear. ITS-1 DNA was sequenced and revealed 100% identity of the strain in the current study to the other L. tropica sequences identified from the patients with the suspected CL and inhabited the same study area. The current findings confirmed the susceptibility of gerbil to L. tropica, and raise the concerns for the role of rodents as accidental host suffering the infections. The susceptibility of wild and experimental rodents to the same L. tropica strain was also investigated; BALB/c and G. pyramidum were more susceptible to L. tropica (24.33 ± 4.37 and 25 ± 4.58 days post-infection, respectively). Similar viscerotropic pathologies were reported in experimental infection of only golden hamster (≈ 120 days post-infection), and G. p. floweri (≈ 160 days post-infection).

  13. Bovine mastitis caused by Listeria monocytogenes: characteristics of natural and experimental infections.

    Science.gov (United States)

    Bourry, A; Poutrel, B; Rocourt, J

    1995-08-01

    Experimental mastitis induced with a single intramammary injection of Listeria monocytogenes was compared with two naturally occurring cases. Four strains of L. monocytogenes, two of serotype 1/2a and two of serotype 4b were used for the experimental infections and two diametrically opposed quarters of four cows were inoculated with 300 cfu. Bacteriological examination and somatic cell counts of quarter foremilk samples were performed weekly for at least 6 months after challenge. All the inoculated quarters developed chronic subclinical mastitis with occasional clinical episodes. The results were similar to those observed in natural listeria mastitis. Four experimentally infected quarters were treated during lactation (gentamicin and cloxacillin) or at "drying-off" (cloxacillin), or at both times. Only one of four quarters was cured after treatment only at "drying-off". All experimental and naturally infected animals were slaughtered and bacteriological examination was performed on liver, spleen and supramammary, iliac and mesenteric lymph nodes. L. monocytogenes strains were isolated from the supramammary lymph nodes of two experimentally and two naturally infected cows and from an iliac lymph node from one of the naturally infected cows. The epidemiological data were supported by serotyping, lysotyping and DNA macro-restriction analysis. The experimental model of listeria mastitis mimics spontaneous cases and should be useful in further studies of listeria mastitis.

  14. Experimental Infection of the Skin in the Hamster Simulating Human Impetigo IV. Cellular Responses after Streptococcal and Staphylococcal Infections

    Science.gov (United States)

    Dajani, Adnan S.; Wannamaker, Lewis W.

    1972-01-01

    Various cellular responses to skin infections in an experimental animal model were explored. Total leukocyte counts varied after group A streptococcal infections, but a depression was commonly seen after M type 12 impetigo. Staphylococcus aureus infections resulted in moderate leukocytosis. A marked neutrophilia was universal with streptococcal or staphylococcal disease. A positive nitroblue tetrazolium (NBT) response appeared 24 hr after infection, reached a peak in 48 hr, and then declined. This occurred in the absence of extensive cellulitis or bacteremia. An increase in the percentage and absolute number of NBT-positive neutrophils occurred. M type 57 streptococcus produced a more strongly positive NBT test than did M type 12. Cell-free filtrates of a broth culture of M type 57 streptococcus produced NBT responses in hamsters comparable to the responses seen after injection of live organisms. These studies indicate the usefulness of this animal model to study various parameters of the NBT test. PMID:4117885

  15. Experimental infections of baboons (Papio spp. and vervet monkeys (Cercopithecus aethiops with Trichinella zimbabwensis and successful treatment with ivermectin

    Directory of Open Access Journals (Sweden)

    S. Mukaratirwa

    2008-08-01

    Full Text Available Experimental Trichinella zimbabwensis infections were established in three baboons (Papios p.and four vervet monkeys (Cercopithecuase thiops and the clinical-pathological manifestations assessed. The infected animals showed clinical signs ranging from fever, diarrhoea, periorbitaol edema and muscular pain in varying degrees. One baboon became blind due to the infection. Levels of creatinine phosphokinase and lactated ehydrogenase increased to reach a peak on Day 42 post-infection(pifor both baboons and monkeys. Blood parameters such as packed cell volume, levels of red blood cells and white blood cells did not change significantly from the normal ranges except for the levels of eosinophils which peaked above the normal ranges at Day 28 and 56 pi in baboons and at Day 56 pi in monkeys.

  16. 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...

  17. Plasma and tissue pharmacokinetics of marbofloxacin in experimentally infected chickens with Mycoplasma gallisepticum and Escherichia coli.

    Science.gov (United States)

    Ding, H; Wang, L; Shen, X; Gu, X; Zeng, D; Zeng, Z

    2013-10-01

    The plasma and tissue pharmacokinetics of marbofloxacin in chickens experimentally infected with Mycoplasma gallisepticum and Escherichia coli were studied. Marbofloxacin was given to 66 infected chickens by oral administration at a dosage of 5 mg/kg b.w., once a day for three days. Plasma, brain, kidney, liver, lung, muscle and trachea were collected and marbofloxacin concentrations were analyzed by a high performance liquid chromatography method. In the infected chickens, maximal marbofloxacin concentrations in plasma, brain, kidney, liver, lung, muscle and trachea were 1.84, 1.33, 7.35, 5.61, 3.12, 2.98, and 4.51 g/mL (g); the elimination half-lives of marbofloxacin were 6.8, 2.74, 9.31, 8.45, 9.55, 11.53 and 5.46 h for plasma, brain, kidney, liver, lung, muscle and trachea, respectively. AUC were calculated to be 9.68, 8.04, 45.1, 27.03, 20.56, 19.47, and 32.68 μg/mL (g) for plasma, brain, kidney, liver, lung, muscle and trachea, respectively. Marbofloxacin concentration in tissues except for brain exceeded marbofloxacin concentration in plasma, with AUC(tissue) /AUC(plasma) ranging from 2.01 to 4.66 and Peak(tissue) /Peak(plasma) ranging from 1.62 to 3.99. The results showed that a marbofloxacin dosage of 5 mg/kg administered orally at 24 h intervals may provide successful treatment of chicken with MG and E. coli infection. © 2013 John Wiley & Sons Ltd.

  18. [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.

  19. A new formulation of cannabidiol in cream shows therapeutic effects in a mouse model of experimental autoimmune encephalomyelitis.

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    Giacoppo, Sabrina; Galuppo, Maria; Pollastro, Federica; Grassi, Gianpaolo; Bramanti, Placido; Mazzon, Emanuela

    2015-10-21

    The present study was designed to investigate the efficacy of a new formulation of alone, purified cannabidiol (CBD) (>98 %), the main non-psychotropic cannabinoid of Cannabis sativa, as a topical treatment in an experimental model of autoimmune encephalomyelitis (EAE), the most commonly used model for multiple sclerosis (MS). Particularly, we evaluated whether administration of a topical 1 % CBD-cream, given at the time of symptomatic disease onset, could affect the EAE progression and if this treatment could also recover paralysis of hind limbs, qualifying topical-CBD for the symptomatic treatment of MS. In order to have a preparation of 1 % of CBD-cream, pure CBD have been solubilized in propylene glycoland basic dense cream O/A. EAE was induced by immunization with myelin oligodendroglial glycoprotein peptide (MOG35-55) in C57BL/6 mice. After EAE onset, mice were allocated into several experimental groups (Naïve, EAE, EAE-1 % CBD-cream, EAE-vehicle cream, CTRL-1 % CBD-cream, CTRL-vehicle cream). Mice were observed daily for signs of EAE and weight loss. At the sacrifice of the animals, which occurred at the 28(th) day from EAE-induction, spinal cord and spleen tissues were collected in order to perform histological evaluation, immunohistochemistry and western blotting analysis. Achieved results surprisingly show that daily treatment with topical 1 % CBD-cream may exert neuroprotective effects against EAE, diminishing clinical disease score (mean of 5.0 in EAE mice vs 1.5 in EAE + CBD-cream), by recovering of paralysis of hind limbs and by ameliorating histological score typical of disease (lymphocytic infiltration and demyelination) in spinal cord tissues. Also, 1 % CBD-cream is able to counteract the EAE-induced damage reducing release of CD4 and CD8α T cells (spleen tissue localization was quantified about 10,69 % and 35,96 % of positive staining respectively in EAE mice) and expression of the main pro-inflammatory cytokines as well as several other

  20. Experimental infection of meadow voles (Microtus pennsylvanicus) with sheep scrapie

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    Carlson, CM; Schneider, Jay R.; Pedersen, Janice C.; Heisey, Dennis M.; Johnson, Christopher J.

    2015-01-01

    Meadow voles (Microtus pennsylvanicus) are permissive to chronic wasting disease (CWD) infection, but their susceptibility to other transmissible spongiform encephalopathies (TSEs) is poorly characterized. In this initial study, we intracerebrally challenged 6 meadow voles with 2 isolates of sheep scrapie. Three meadow voles acquired a TSE after the scrapie challenge and an extended incubation period. The glycoform profile of proteinase K-resistant prion protein (PrP(res)) in scrapie-sick voles remained similar to the sheep inocula, but differed from that of voles clinically affected by CWD. Vacuolization patterns and disease-associated prion protein (PrP(Sc)) deposition were generally similar in all scrapie-affected voles, except in the hippocampus, where PrP(Sc) staining varied markedly among the animals. Our results demonstrate that meadow voles can acquire a TSE after intracerebral scrapie challenge and that this species could therefore prove useful for characterizing scrapie isolates.

  1. Genetic Resistance to Scrapie Infection in Experimentally Challenged Goats

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    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

  2. Experimental and Natural Infections of Goats with Severe Fever with Thrombocytopenia Syndrome Virus: Evidence for Ticks as Viral Vector.

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    Yongjun Jiao

    Full Text Available Severe fever with thrombocytopenia syndrome virus (SFTSV, the causative agent for the fatal life-threatening infectious disease, severe fever with thrombocytopenia syndrome (SFTS, was first identified in the central and eastern regions of China. Although the viral RNA was detected in free-living and parasitic ticks, the vector for SFTSV remains unsettled.Firstly, an experimental infection study in goats was conducted in a bio-safety level-2 (BSL-2 facility to investigate virus transmission between animals. The results showed that infected animals did not shed virus to the outside through respiratory or digestive tract route, and the control animals did not get infected. Then, a natural infection study was carried out in the SFTSV endemic region. A cohort of naïve goats was used as sentinel animals in the study site. A variety of daily samples including goat sera, ticks and mosquitoes were collected for viral RNA and antibody (from serum only detection, and virus isolation. We detected viral RNA from free-living and parasitic ticks rather than mosquitoes, and from goats after ticks' infestation. We also observed sero-conversion in all members of the animal cohort subsequently. The S segment sequences of the two recovered viral isolates from one infected goat and its parasitic ticks showed a 100% homology at the nucleic acid level.In our natural infection study, close contact between goats does not appear to transmit SFTSV, however, the naïve animals were infected after ticks' infestation and two viral isolates derived from an infected goat and its parasitic ticks shared 100% of sequence identity. These data demonstrate that the etiologic agent for goat cohort's natural infection comes from environmental factors. Of these, ticks, especially the predominant species Haemaphysalis longicornis, probably act as vector for this pathogen. The findings in this study may help local health authorities formulate and focus preventive measures to contain

  3. Latex protein extracts from Calotropis procera with immunomodulatory properties protect against experimental infections with Listeria monocytogenes.

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    Nascimento, Danielle Cristina de Oliveira; Ralph, Maria Taciana; Batista, Jacqueline Ellen Camelo; Silva, Diogo Manoel Farias; Gomes-Filho, Manoel Adrião; Alencar, Nylane Maria; Leal, Nilma Cintra; Ramos, Márcio Viana; Lima-Filho, Jose Vitor

    2016-06-15

    The latex from the medicinal plant Calotropis procera is often used in folk medicine against infectious and inflammatory diseases. In this study, we investigate a protein fraction with immunomodulatory properties, named LPPI, against experimental infections, in vitro and in vivo, with a virulent strain of Listeria monocytogenes. LPPI was exposed to cultured macrophages or Swiss mice and then challenged with L. monocytogenes. Peritoneal macrophages were obtained from Swiss mice, and cultured in 96-well microplates. Soluble latex proteins (LP) were subjected to fractionation by ion-exchange chromatography. The major peak (LPPI) was added into wells at 10 or 100µg/ml. Albumin (100µg/ml) was used for comparison between protein treatments. After incubation for 1h at 5% CO2/ 37°C, the supernatant was discarded and 0.2ml of L. monocytogenes overnight culture was added in the wells. Following 4h and 24h infection, the cytokine mRNA expression was evaluated as well as the number of intracellular colony forming units. Swiss mice (n=16) were injected intraperitoneally (i.p.) with LPPI (5 and 10mg/kg) while the control mice received albumin (10mg/kg) or LP (10mg/kg). After 24h, all animal groups were challenged with L. monocytogenes (10(6) CFU/ ml), also by i.p. route. LPPI was not toxic to uninfected macrophages (pMØ) and significantly increased mRNA expression of TNF-α, IL-6, IL-1β and iNOS. Following infection, cell viability was reduced by 50% in albumin-treated pMØ (control); but only 17% in pMØ treated with LPPI at 100µg/ml. In this case, LPPI increased expression of TNF-α and IL-6 whereas the number of bacterial colony-forming units was reduced 100-fold in comparison to control groups. Swiss mice pretreated with LPPI showed dose-dependent survival rates that reached 80%, while mice that received albumin died 1-3 days after infection. After 24h infection, leukocyte migration to the infectious foci was high in LPPI-treated mice whereas the number of viable

  4. Trypanosoma cruzi-Trypanosoma rangeli co-infection ameliorates negative effects of single trypanosome infections in experimentally infected Rhodnius prolixus.

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    Peterson, Jennifer K; Graham, Andrea L; Elliott, Ryan J; Dobson, Andrew P; Triana Chávez, Omar

    2016-08-01

    Trypanosoma cruzi, causative agent of Chagas disease, co-infects its triatomine vector with its sister species Trypanosoma rangeli, which shares 60% of its antigens with T. cruzi. Additionally, T. rangeli has been observed to be pathogenic in some of its vector species. Although T. cruzi-T. rangeli co-infections are common, their effect on the vector has rarely been investigated. Therefore, we measured the fitness (survival and reproduction) of triatomine species Rhodnius prolixus infected with just T. cruzi, just T. rangeli, or both T. cruzi and T. rangeli. We found that survival (as estimated by survival probability and hazard ratios) was significantly different between treatments, with the T. cruzi treatment group having lower survival than the co-infected treatment. Reproduction and total fitness estimates in the T. cruzi and T. rangeli treatments were significantly lower than in the co-infected and control groups. The T. cruzi and T. rangeli treatment group fitness estimates were not significantly different from each other. Additionally, co-infected insects appeared to tolerate higher doses of parasites than insects with single-species infections. Our results suggest that T. cruzi-T. rangeli co-infection could ameliorate negative effects of single infections of either parasite on R. prolixus and potentially help it to tolerate higher parasite doses.

  5. Cysticercosis in experimentally and naturally infected pigs: parasitological and immunological diagnosis

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    Márcia R.M. da Silva

    2012-04-01

    Full Text Available Our objective was to evaluate the diagnosis of swine cysticercosis by examining "ante mortem" (inspection of the tongue, "post mortem" (inspection and detailed necropsy and ELISA for research in serum of antibodies (Ab-ELISA and antigens (Ag-ELISA. Seven (7 pigs were experimentally infected orally with eggs of Taenia solium and another 10 were naturally infected. In the pigs experimentally infected, inspection of the tongue was negative in all animals, in the routine inspection detailed necropsy and cysticercis were identified in all of them. In pigs with heavy natural infection, inspection of the tongue identified cysticerci in two (20%, while at inspection with necropsy the parasites were identified in large quantities in all animals. In ELISA for antibody search (Ab-ELISA TS-14 recombinant protein was used, and in search for antigen (Ag-ELISA a monoclonal antibody against this protein. In animals experimentally infected, blood was collected weekly for 140 days. The Ab-ELISA identified an increase in titers of antibody to cysticerci 21 days after infection, and at the end of the experimental period six animals (86% were positive to the test. The search for circulating antigens (Ag-ELISA was positive in two pigs 28 to 91 days after infection. All naturally infected pigs were positive for Ag-ELISA and Ab-ELISA. The search for antibodies and antigens by ELISA in serum from 30 pigs of a local farm and without history of cysticercosis was negative. Thus, the use of TS-14 antigen in ELISA test (Ab-ELISA can be useful for the diagnosis of cysticercosis in pigs with low infection.

  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. Experimental and molecular dynamics studies showed that CBP KIX mutation affects the stability of CBP:c-Myb complex.

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    Odoux, Anne; Jindal, Darren; Tamas, Tamara C; Lim, Benjamin W H; Pollard, Drake; Xu, Wu

    2016-06-01

    The coactivators CBP (CREBBP) and its paralog p300 (EP300), two conserved multi-domain proteins in eukaryotic organisms, regulate gene expression in part by binding DNA-binding transcription factors. It was previously reported that the CBP/p300 KIX domain mutant (Y650A, A654Q, and Y658A) altered both c-Myb-dependent gene activation and repression, and that mice with these three point mutations had reduced numbers of platelets, B cells, T cells, and red blood cells. Here, our transient transfection assays demonstrated that mouse embryonic fibroblast cells containing the same mutations in the KIX domain and without a wild-type allele of either CBP or p300, showed decreased c-Myb-mediated transcription. Dr. Wright's group solved a 3-D structure of the mouse CBP:c-Myb complex using NMR. To take advantage of the experimental structure and function data and improved theoretical calculation methods, we performed MD simulations of CBP KIX, CBP KIX with the mutations, and c-Myb, as well as binding energy analysis for both the wild-type and mutant complexes. The binding between CBP and c-Myb is mainly mediated by a shallow hydrophobic groove in the center where the side-chain of Leu302 of c-Myb plays an essential role and two salt bridges at the two ends. We found that the KIX mutations slightly decreased stability of the CBP:c-Myb complex as demonstrated by higher binding energy calculated using either MM/PBSA or MM/GBSA methods. More specifically, the KIX mutations affected the two salt bridges between CBP and c-Myb (CBP-R646 and c-Myb-E306; CBP-E665 and c-Myb-R294). Our studies also revealed differing dynamics of the hydrogen bonds between CBP-R646 and c-Myb-E306 and between CBP-E665 and c-Myb-R294 caused by the CBP KIX mutations. In the wild-type CBP:c-Myb complex, both of the hydrogen bonds stayed relatively stable. In contrast, in the mutant CBP:c-Myb complex, hydrogen bonds between R646 and E306 showed an increasing trend followed by a decreasing trend, and hydrogen

  8. 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.

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    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.

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

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    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.

  10. Intra-uterine experimental infection by Ureaplasma diversum induces TNF-α mediated womb inflammation in mice

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    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.

  11. Natural and experimental West Nile virus infection in five raptor species.

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    Nemeth, Nicole; Gould, Daniel; Bowen, Richard; Komar, Nicholas

    2006-01-01

    We studied the effects of natural and/or experimental infections of West Nile virus (WNV) in five raptor species from July 2002 to March 2004, including American kestrels (Falco sparverius), golden eagles (Aquila chrysaetos), red-tailed hawks (Buteo jamaicensis), barn owls (Tyto alba), and great horned owls (Bubo virginianus). Birds were infected per mosquito bite, per os, or percutaneously by needle. Many experimentally infected birds developed mosquito-infectious levels of viremia (>10(5) WNV plaque forming units per ml serum) within 5 days postinoculation (DPI), and/ or shed virus per os or per cloaca. Infection of organs 15-27 days postinoculation was infrequently detected by virus isolation from spleen, kidney, skin, heart, brain, and eye in convalescent birds. Histopathologic findings varied among species and by method of infection. The most common histopathologic lesions were subacute myocarditis and encephalitis. Several birds had a more acute, severe disease condition represented by arteritis and associated with tissue degeneration and necrosis. This study demonstrates that raptor species vary in their response to WNV infection and that several modes of exposure (e.g., oral) may result in infection. Wildlife managers should recognize that, although many WNV infections are sublethal to raptors, subacute lesions could potentially reduce viability of populations. We recommend that raptor handlers consider raptors as a potential source of WNV contamination due to oral and cloacal shedding.

  12. Chronic Bee Paralysis Virus and Nosema ceranae Experimental Co-Infection of Winter Honey Bee Workers (Apis mellifera L.

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    Aleš Gregorc

    2013-09-01

    Full Text Available Chronic bee paralysis virus (CBPV is an important viral disease of adult bees which induces significant losses in honey bee colonies. Despite comprehensive research, only limited data is available from experimental infection for this virus. In the present study winter worker bees were experimentally infected in three different experiments. Bees were first inoculated per os (p/o or per cuticle (p/c with CBPV field strain M92/2010 in order to evaluate the virus replication in individual bees. In addition, potential synergistic effects of co-infection with CBPV and Nosema ceranae (N. ceranae on bees were investigated. In total 558 individual bees were inoculated in small cages and data were analyzed using quantitative real time RT-PCR (RT-qPCR. Our results revealed successful replication of CBPV after p/o inoculation, while it was less effective when bees were inoculated p/c. Dead bees harbored about 1,000 times higher copy numbers of the virus than live bees. Co-infection of workers with CBPV and N. ceranae using either method of virus inoculation (p/c or p/o showed increased replication ability for CBPV. In the third experiment the effect of inoculation on bee mortality was evaluated. The highest level of bee mortality was observed in a group of bees inoculated with CBPV p/o, followed by a group of workers simultaneously inoculated with CBPV and N. ceranae p/o, followed by the group inoculated with CBPV p/c and the group with only N. ceranae p/o. The experimental infection with CBPV showed important differences after p/o or p/c inoculation in winter bees, while simultaneous infection with CBPV and N. ceranae suggesting a synergistic effect after inoculation.

  13. Chronic bee paralysis virus and Nosema ceranae experimental co-infection of winter honey bee workers (Apis mellifera L.).

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    Toplak, Ivan; Jamnikar Ciglenečki, Urška; Aronstein, Katherine; Gregorc, Aleš

    2013-09-19

    Chronic bee paralysis virus (CBPV) is an important viral disease of adult bees which induces significant losses in honey bee colonies. Despite comprehensive research, only limited data is available from experimental infection for this virus. In the present study winter worker bees were experimentally infected in three different experiments. Bees were first inoculated per os (p/o) or per cuticle (p/c) with CBPV field strain M92/2010 in order to evaluate the virus replication in individual bees. In addition, potential synergistic effects of co-infection with CBPV and Nosema ceranae (N. ceranae) on bees were investigated. In total 558 individual bees were inoculated in small cages and data were analyzed using quantitative real time RT-PCR (RT-qPCR). Our results revealed successful replication of CBPV after p/o inoculation, while it was less effective when bees were inoculated p/c. Dead bees harbored about 1,000 times higher copy numbers of the virus than live bees. Co-infection of workers with CBPV and N. ceranae using either method of virus inoculation (p/c or p/o) showed increased replication ability for CBPV. In the third experiment the effect of inoculation on bee mortality was evaluated. The highest level of bee mortality was observed in a group of bees inoculated with CBPV p/o, followed by a group of workers simultaneously inoculated with CBPV and N. ceranae p/o, followed by the group inoculated with CBPV p/c and the group with only N. ceranae p/o. The experimental infection with CBPV showed important differences after p/o or p/c inoculation in winter bees, while simultaneous infection with CBPV and N. ceranae suggesting a synergistic effect after inoculation.

  14. Histopathological, immunohistochemical, and molecular study of BHV-5 infection in the central nervous system of experimentally infected calves

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    Didier Q. Cagnini

    2015-04-01

    Full Text Available Bovine meningoencephalitis caused by BHV-5, a double-stranded DNA enveloped virus that belongs to the family Herpesviridae and subfamily Alphaherpesvirinae, is an important differential diagnosis of central nervous diseases. The aim of this study was to describe the histological changes in the central nervous system of calves experimentally infected with BHV-5 and compare these changes with the PCR and IHC results. Formalin-fixed paraffin-embedded central nervous system samples from calves previously inoculated with BHV-5 were microscopically evaluated and tested using IHC and PCR. All the animals presented with nonsuppurative meningoencephalitis. From 18 evaluated areas of each calf, 32.41% and 35.19% were positive by IHC and PCR, respectively. The telencephalon presented more accentuated lesions and positive areas in the PCR than other encephalic areas and was the best sampling area for diagnostic purposes. Positive areas in the IHC and PCR were more injured than IHC and PCR negative areas. The animal with neurological signs showed more PCR- and IHC-positive areas than the other animals.

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

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    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.

  16. Experimental Manipulation Shows a Greater Influence of Population than Dietary Perturbation on the Microbiome of Tyrophagus putrescentiae.

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    Erban, Tomas; Ledvinka, Ondrej; Nesvorna, Marta; Hubert, Jan

    2017-05-01

    Tyrophagus putrescentiae is inhabited by bacteria that differ among mite populations (strains) and diets. Here, we investigated how the microbiome and fitness of Tputrescentiae are altered by dietary perturbations and mite populations. Four T. putrescentiae populations, referred to as dog, Koppert, laboratory, and Phillips, underwent a perturbation, i.e., a dietary switch from a rearing diet to two experimental diets. The microbiome was investigated by sequencing the V1-V3 portion of the 16S rRNA gene, and selected bacterial taxa were quantified by quantitative PCR (qPCR) using group/taxon-specific primers. The parameters observed were the changes in mite population growth and nutritional status, i.e., the total glycogen, lipid, saccharide, and protein contents in mites. The effect of diet perturbation on the variability of the microbiome composition and population growth was lower than the effect induced by mite population. In contrast, the diet perturbation showed a greater effect on nutritional status of mites than the mite population. The endosymbionts exhibited high variations among T. putrescentiae populations, including Cardinium in the laboratory population, Blattabacterium-like bacteria in the dog population, and Wolbachia in the dog and Phillips populations. Solitalea-like and Bartonella-like bacteria were present in the dog, Koppert, and Phillips populations in different proportions. The T. putrescentiae microbiome is dynamic and varies based on both the mite population and perturbation; however, the mites remain characterized by robust bacterial communities. Bacterial endosymbionts were found in all populations but represented a dominant portion of the microbiome in only some populations.IMPORTANCE We addressed the question of whether population origin or perturbation exerts a more significant influence on the bacterial community of the stored product mite Tyrophagus putrescentiae The microbiomes of four populations of T. putrescentiae insects subjected

  17. Improved BM212 MmpL3 inhibitor analogue shows efficacy in acute murine model of tuberculosis infection.

    Directory of Open Access Journals (Sweden)

    Giovanna Poce

    Full Text Available 1,5-Diphenyl pyrroles were previously identified as a class of compounds endowed with high in vitro efficacy against M. tuberculosis. To improve the physical chemical properties and drug-like parameters of this class of compounds, a medicinal chemistry effort was undertaken. By selecting the optimal substitution patterns for the phenyl rings at N1 and C5 and by replacing the thiomorpholine moiety with a morpholine one, a new series of compounds was produced. The replacement of the sulfur with oxygen gave compounds with lower lipophilicity and improved in vitro microsomal stability. Moreover, since the parent compound of this family has been shown to target MmpL3, mycobacterial mutants resistant to two compounds have been isolated and characterized by sequencing the mmpL3 gene; all the mutants showed point mutations in this gene. The best compound identified to date was progressed to dose-response studies in an acute murine TB infection model. The resulting ED(99 of 49 mg/Kg is within the range of commonly employed tuberculosis drugs, demonstrating the potential of this chemical series. The in vitro and in vivo target validation evidence presented here adds further weight to MmpL3 as a druggable target of interest for anti-tubercular drug discovery.

  18. Experimental infection by Yersinia ruckeri O1 biotype 2 induces brain lesions and neurological signs in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Strøm, H K; Ohtani, M; Nowak, B; Boutrup, T S; Jones, B; Raida, M K; Bojesen, A M

    2017-11-17

    Pathological manifestations in rainbow trout (Oncorhynchus mykiss) following experimental waterborne infection with Yersinia ruckeri serotype O1 biotype 2 (strain 07111224) were investigated. Rainbow trout were exposed to 8 × 107  CFU/ml of Y. ruckeri by bath for 6 hr, and mortality was then monitored for 22 days post-infection (dpi). Organs were sampled at 3 dpi and also from moribund fish showing signs of severe systemic infection such as bleeding, exophthalmia or erratic swimming behaviour. Y. ruckeri was observed in the meninges and diencephalon of the brain, and lamina propria of olfactory organ at 3 dpi. At 12 dpi, Y. ruckeri had spread throughout the brain including cranial connective tissues and ventricles and the infection was associated with haemorrhages and an infiltration with leucocytes. Y. ruckeri infection and associated with leucocyte infiltration were observed at 13 dpi. In conclusion, Y. ruckeri strain 07111224 causes encephalitis in the acute phase of infection, which could explain why Y. ruckeri-affected fish show exophthalmia and erratic swimming known as signs of ERM. © 2017 John Wiley & Sons Ltd.

  19. Hematological and cerebrospinal fluid changes in cattle naturally and experimentally infected with the bovine herpesvirus 5

    Directory of Open Access Journals (Sweden)

    Júlio Augusto Naylor Lisbôa

    2009-11-01

    Full Text Available Bovine herpesvirus 5 (BoHV-5 meningoencephalitis is one of the main causes of mortality by encephalopathy in Brazilian cattle herds. However, the neurological signs observed are common to several encephalopathies and do not contribute decisively to a diagnosis. In order to verify hematological and cerebrospinal fluid (CSF changes, blood and CSF samples from naturally and experimentally infected bovines were evaluated. In natural cases (n=17, the samples were collected only once, and in experimental cases (n=7, the samples were sequentially obtained throughout disease progression. While routine methods were used to examine the samples, BoHV-5 infection was confirmed by a PCR assay. Blood analyses did not reveal any consistent hematological alterations and the leukogram results occasionally showed increases in leukocyte and segmented neutrophil. Hyperfibrinogenemia was noted in all experimentally infected calves and in half of the natural cases. Pleocytosis with mononuclear cells was a remarkable finding in CSF collected from both groups of animals and was present even in experimentally infected calves that remained asymptomatic. Therefore, CSF evaluation can be used as an auxiliary method in ante-mortem BoHV-5 diagnosis.A meningoencefalite determinada pelo herpesvírus bovino 5 (BoHV-5 é considerada uma das principais causas de mortalidade por encefalopatia em bovinos no Brasil. O diagnóstico clínico da infecção é difícil de ser realizado pois os sinais neurológicos ocasionados pela infecção com o BoHV-5 são comuns aos observados em encefalopatias bovinas de diferentes etiologias. Com o objetivo de determinar as alterações hematológicas e do líquido cefalorraquidiano, foram avaliadas amostras de sangue total e líquor colhidas de animais infectados tanto naturalmente quanto experimentalmente. Nos casos naturais da doença (n=17, as amostras foram coletadas apenas uma vez. Nos casos de infecção experimental (n=7, as amostras foram

  20. Experimental Hendra virus infection of dogs: virus replication, shedding and potential for transmission.

    Science.gov (United States)

    Middleton, D J; Riddell, S; Klein, R; Arkinstall, R; Haining, J; Frazer, L; Mottley, C; Evans, R; Johnson, D; Pallister, J

    2017-01-01

    Characterisation of experimental Hendra virus (HeV) infection in dogs and assessment of associated transmission risk. Beagle dogs were exposed oronasally to Hendra virus/Australia/Horse/2008/Redlands or to blood collected from HeV-infected ferrets. Ferrets were exposed to oral fluids collected from dogs after canine exposure to HeV. Observations made and samples tested post-exposure were used to assess the clinical course and replication sites of HeV in dogs, the infectivity for ferrets of canine oral fluids and features of HeV infection in dogs following contact with infective blood. Dogs were reliably infected with HeV and were generally asymptomatic. HeV was re-isolated from the oral cavity and virus clearance was associated with development of virus neutralising antibody. Major sites of HeV replication in dogs were the tonsils, lower respiratory tract and associated lymph nodes. Virus replication was documented in canine kidney and spleen, confirming a viraemic phase for canine HeV infection and suggesting that urine may be a source of infectious virus. Infection was transmitted to ferrets via canine oral secretions, with copy numbers for the HeV N gene in canine oral swabs comparable to those reported for nasal swabs of experimentally infected horses. HeV is not highly pathogenic for dogs, but their oral secretions pose a potential transmission risk to people. The time-window for transmission risk is circumscribed and corresponds to the period of acute infection before establishment of an adaptive immune response. The likelihood of central nervous system involvement in canine HeV infection is unclear, as is any long-term consequence. © 2017 Australian Veterinary Association.

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

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    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.

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

    DEFF Research Database (Denmark)

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

    2006-01-01

    The outcome of experimental intestinal infections with enterotoxigenic Escherichia coli (ETEC) is dependent on several factors. An important factor is adhesion of the challenge strain to the intestinal mucosa. The test for susceptibility towards ETEC adhesion has so far been made by an intestinal...... 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......-gastric intubated with 10(9) CFU of ETEC O149:F4ac and 23 age-matched piglets, both susceptible and resistant, were used as non-infected controls. Of susceptible piglets, challenged with ETEC 0149:F4ac, 74% had ETEC O149:F4ac-associated diarrhoea first day after first challenge, which were significantly higher...

  3. An experimental Helicobacter suis infection causes gastritis and reduced daily weight gain in pigs.

    Science.gov (United States)

    De Bruyne, Ellen; Flahou, Bram; Chiers, Koen; Meyns, Tom; Kumar, Smitha; Vermoote, Miet; Pasmans, Frank; Millet, Sam; Dewulf, Jeroen; Haesebrouck, Freddy; Ducatelle, Richard

    2012-12-07

    Helicobacter suis is a zoonotically important bacterium, that has been associated with gastritis and ulcerative lesions of the pars oesophagea of the stomach in pigs. Its exact role in these pathologies, however, still remains controversial. Therefore, a total of 29 medicated early weaned piglets were inoculated intragastrically or orally, with a total of 2 × 10(9) viable H. suis bacteria and the effect on gastric pathology and weight gain was determined. Twenty-three medicated early weaned piglets were inoculated with a sterile culture medium and used as sham-inoculated controls. The animals were euthanized between 28 and 42 days after inoculation. Infected animals showed a more severe gastritis compared to the control group. There was also a significant reduction of approximately 60 g per day (10%) in weight gain in H. suis inoculated animals compared to the sham-inoculated control animals. In conclusion, this study demonstrates for the first time that a pure in vitro culture of H. suis not only causes gastritis but also a marked decrease of the daily weight gain in experimentally infected pigs. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Eimeria stiedai: Metabolism of lipids, proteins and glucose in experimentally infected rabbits, Oryctolagus cuniculus

    OpenAIRE

    Freitas, Fagner L. C.; Yamamoto, Beatriz L.; Freitas, Wagner L. C; Almeida, Katyane S; Machado, Rosangela Z. [UNESP; Machado, Célio R. [UNESP

    2010-01-01

    Rabbits were experimentally infected with sporulated Eimeria stiedai oocysts. A total of 50 white adult rabbits, New Zealand race, were distributed into two groups: Group A was infected with 1x10 4 sporulated Eimeria stiedai oocysts, while group B was inoculated with distilled water as a control. The animals generally displayed increased levels of total protein, globulin, total cholesterol, LDL-c and triacylglycerols; however, total levels of liver lipids and HDL-c decreased, and plasma gluco...

  5. Experimental Infection of Rabbits with Rabbit and Genotypes 1 and 4 Hepatitis E Viruses

    OpenAIRE

    Ma, H. X.; Zheng, L.; Liu, Y. B.; Zhao, C. Y.; Harrison, T. J.; Ma, Y. Y.; Sun, S. H.; Zhang, J. G.; Wang, Y. C.

    2010-01-01

    BACKGROUND: A recent study provided evidence that farmed rabbits in China harbor a novel hepatitis E virus (HEV) genotype. Although the rabbit HEV isolate had 77-79% nucleotide identity to the mammalian HEV genotypes 1 to 4, their genomic organization is very similar. Since rabbits are used widely experimentally, including as models of infection, we investigated whether they constitute an appropriate animal model for human HEV infection. METHODS: Forty-two SPF rabbits were divided randomly in...

  6. 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 ... juice. Commercially available cranberry juice cocktail also significantly reduced (P juice (P juice, were tested...... in combination and individually. The four organic acids also decreased bacterial levels in the bladder when administered together (P plus citric acid (P plus quinic acid (P

  7. Efficacy of domestic cooking inactivation of human hepatitis A virus in experimentally infected manila clams (Ruditapes philippinarum).

    Science.gov (United States)

    Pascoli, F; Pezzuto, A; Buratin, A; Piovesana, A; Fortin, A; Arcangeli, G; Toffan, A

    2016-10-01

    The aim of this work was to evaluate the efficacy of domestic cooking in inactivating Manila clams experimentally infected with human hepatitis A virus (HAV). Electronic temperature probes were positioned to measure the internal temperature of Manila clams during domestic cooking. Two batches were infected with 10(7) and 10(5) TCID50  ml(-1) of HAV. The infected whole-in-shell clams were divided into three replicates and cooked on a conventional stove both singularly and in group and removed from the pan at fixed intervals. Pools of three digestive glands were examined by virus isolation for three blind passages and cell culture supernatant tested with real-time PCR. Results showed that 2-min cooking by a traditional domestic method at a temperature close to 100°C, after the opening up of the valves of all the clams, can completely devitalize the HAV in high viral load-infected clams. This is the first study on inactivation of HAV in experimentally infected Manila clams subjected to domestic cooking. At present, labelling all lagoon products as 'requiring cooking before consumption' is highly recommended, but no specifications are given on how long and at what temperature they should be cooked. Considering the high commercial value of Manila clams, our results can provide both the producers and the consumer with useful indications on how to cook clams to prevent the risk of HAV foodborne illness. © 2016 The Society for Applied Microbiology.

  8. Experimental results showing the internal three-component velocity field and outlet temperature contours for a model gas turbine combustor

    CSIR Research Space (South Africa)

    Meyers, BC

    2011-09-01

    Full Text Available A three-component flow field inside a can-type, forward flow experimental combustor was measured under non-reacting conditions. The combustor was run at atmospheric conditions with the air flow supplied from a fan and the outlet was straight...

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

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    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.

  10. Respiratory and neurological disease in rabbits experimentally infected with equid herpesvirus 1.

    Science.gov (United States)

    Kanitz, Fábio A; Cargnelutti, Juliana F; Anziliero, Deniz; Gonçalves, Kelley V; Masuda, Eduardo K; Weiblen, Rudi; Flores, Eduardo F

    2015-10-01

    Equid herpesvirus type 1 (EHV-1) is an important pathogen of horses worldwide, associated with respiratory, reproductive and/or neurological disease. A mouse model for EHV-1 infection has been established but fails to reproduce some important aspects of the viral pathogenesis. Then, we investigated the susceptibility of rabbits to EHV-1 aiming at proposing this species as an alternative model for EHV-1 infection. Weanling rabbits inoculated intranasal with EHV-1 Kentucky D (10(7) TCID50/animal) shed virus in nasal secretions up to day 8-10 post-inoculation (pi), presented viremia up to day 14 pi and seroconverted to EHV-1 (virus neutralizing titers 4 to 64). Most rabbits (75%) developed respiratory disease, characterized by serous to hemorrhagic nasal discharge and mild to severe dyspnea. Some animals (20%) presented neurological signs as circling, bruxism and opisthotonus. Six animals died during acute disease (days 3-6); infectious virus and/or viral DNA were detected in the lungs, trigeminal ganglia (TG), olfactory bulbs (OBs) and cerebral cortex/brain (CC). Histological examination showed necrohemorrhagic, multifocal to coalescent bronchointerstitial pneumonia and diffuse alveolar edema. In two rabbits euthanized at day 50 pi, latent EHV-1 DNA was detected in the OBs. Dexamethasone administration at day 50 pi resulted in virus reactivation, demonstrated by virus shedding, viremia, clinical signs, and increase in VN titers and/or by detection of virus DNA in lungs, OBs, TGs and/or CC. These results demonstrate that rabbits are susceptible to EHV-1 infection and develop respiratory and neurological signs upon experimental inoculation. Thus, rabbits may be used to study selected aspects of EHV-1 biology and pathogenesis, extending and complementing the mouse model. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

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    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.

  12. Development of an experimental model of infected bone void in the ulna of rabbits

    Science.gov (United States)

    Lemos Azi, Matheus; Kfuri Junior, Mauricio; Martinez, Roberto; Salata, Luis Antonio; Paccola, Cleber Antonio Jansen

    2012-01-01

    Objective Develop a model that allowed the study of bone regeneration in infection conditions. Method A 15 mm defect was surgically created in the rabbit ulna and inoculated with 5x108 colony-forming units (CFU) of S. aureus. Surgical debridement was performed two weeks after and systemic gentamicin was administered for four weeks. Animals were followed up to 12 weeks to evaluate infection control and bone regeneration. Result Bone regeneration was inferior to 25% of the defect in radiological and histological analysis. Conclusion Infected bone defect of 15 mm in the rabbit ulna was unable to achieve full regeneration without further treatment. Level of Evidence V, Experimental Study. PMID:24453593

  13. Persistence of viral RNA in the brain of experimentally infected mice with coxsackievirus B5

    Directory of Open Access Journals (Sweden)

    Sobotova Z.

    2011-04-01

    Full Text Available The aim of our study was to follow the persistence of viral RNA in selected organs of experimentally infected with coxsackievirus (CV B5 strains from different sources such as a patient’s sample, an environmental sample and a prototype virus strain. Methods . CD-1 mice were infected with CVB5 strain Faulkner the prototype, CVB5 – isolate from treated sewage waste and isolate from patient’s stool sample both identified as CVB5. The viral RNA was detected by RT-PCR using enterovirus primers specific for the non-coding 5' region. Results . We observed presence of RNA in the brain and heart of mice infected with isolate from patient’s stool at day 45 post infection (p. i.. Conclusion. We conclude that CVB5 persists in the brain and heart after oral infection of CD1 mice. The relevance of viral persistence maybe related viral origin and the genetics

  14. Experimental infections of Orchitophrya stellarum (Scuticociliata) in American blue crabs (Callinectes sapidus) and fiddler crabs (Uca minax).

    Science.gov (United States)

    Miller, Terrence L; Small, Hamish J; Peemoeller, Bhae-Jin; Gibbs, David A; Shields, Jeffrey D

    2013-11-01

    Outbreaks of an unidentified ciliate have occurred on several occasions in blue crabs from Chesapeake Bay held during winter months in flow-through systems. The parasite was initially thought to be Mesanophrys chesapeakensis, but molecular analysis identified it as Orchitophyra stellarum, a facultative parasite of sea stars (Asteroidea). We investigated the host-parasite association of O. stellarum in the blue crab host. Crabs were inoculated with the ciliate, or they were held in bath exposures after experimentally induced autotomy of limbs in order to determine potential mechanisms for infection. Crabs inoculated with the ciliate, or exposed to it after experimental autotomy, rapidly developed fatal infections. Crabs that were not experimentally injured, but were exposed to the ciliate, rarely developed infections; thus, indicating that the parasite requires a wound or break in the cuticle as a portal of entry. For comparative purposes, fiddler crabs, Uca minax, were inoculated with the ciliate in a dose-titration experiment. Low doses of the ciliate (10 per crab) were sometimes able to establish infections, but high intensity infections developed quickly at doses over 500 ciliates per crab. Chemotaxis studies were initiated to determine if the ciliate preferentially selected blue crab serum (BCS) over other nutrient sources. Cultures grown on medium with BCS or fetal bovine serum showed some conditioning in their selection for different media, but the outcome in choice experiments indicated that the ciliate was attracted to BCS and not seawater. Our findings indicate that O. stellarum is a facultative parasite of blue crabs. It can cause infections in exposed crabs at 10-15°C, but it requires a portal of entry for successful host invasion, and it may find injured hosts using chemotaxis. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. Pathogenesis and Immunohistochemical Studies of Caprine Pleuropneumonia in Experimentally Infected Goats

    Directory of Open Access Journals (Sweden)

    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.

  16. Clinical pathology of experimental Schistosoma curassoni infections in sheep and goats.

    Science.gov (United States)

    Vercruysse, J; Fransen, J; Southgate, V R; Rollinson, D; Majeleine, W

    1988-05-01

    The clinical pathology of Schistosoma curassoni infection in sheep and goats was studied for 22 weeks following experimental infection with 7000 and 4000 cercariae, respectively. Excretion of eggs began at week 7 after infection: in goats the numbers increased to 30 to 50 eggs per gram faeces (epg) at weeks 8 to 18, followed by a reduction. In a pregnant goat, epg values increased markedly before and after parturition. The mean faecal egg counts in sheep were lower than in goats, increasing to a maximum level of 30 epg at weeks 16 and 17 after infection. Infected sheep maintained growth rates roughly comparable with controls, whereas infected goats failed to gain as much weight as the controls. Infected goats and sheep produced eosinophil counts of about 3 x 10(3) mm-3, five and eight weeks after infection, respectively. Sheep developed a progressive anaemia from week 11 after infection, in goats blood values remained within normal limits. Differences in serum protein concentration were observed between infected and uninfected goats about nine weeks after infection, but not in sheep. Increased total protein values, hyperglobulinaemia and lowered albumin to globulin ratios were features of infected goats. Serum glutamate oxaloacetate transaminase, glutamate pyruvate transaminase, gamma-glutamyl transferase, total lactate dehydrogenase and bilirubin were not significantly changed. The mean recovery in sheep was 608 worms, in goats 428 worms, but the total tissue egg counts were higher in the latter. Of the total eggs deposited in the goats 92 per cent were found in the liver with 51.5 per cent in the ovine liver. The histopathological changes were studied.

  17. Genome-wide expression profiling shows transcriptional reprogramming in Fusarium graminearum by Fusarium graminearum virus 1-DK21 infection

    Directory of Open Access Journals (Sweden)

    Cho Won

    2012-05-01

    Full Text Available Abstract Background Fusarium graminearum virus 1 strain-DK21 (FgV1-DK21 is a mycovirus that confers hypovirulence to F. graminearum, which is the primary phytopathogenic fungus that causes Fusarium head blight (FHB disease in many cereals. Understanding the interaction between mycoviruses and plant pathogenic fungi is necessary for preventing damage caused by F. graminearum. Therefore, we investigated important cellular regulatory processes in a host containing FgV1-DK21 as compared to an uninfected parent using a transcriptional approach. Results Using a 3′-tiling microarray covering all known F. graminearum genes, we carried out genome-wide expression analyses of F. graminearum at two different time points. At the early point of growth of an infected strain as compared to an uninfected strain, genes associated with protein synthesis, including ribosome assembly, nucleolus, and ribosomal RNA processing, were significantly up-regulated. In addition, genes required for transcription and signal transduction, including fungal-specific transcription factors and cAMP signaling, respectively, were actively up-regulated. In contrast, genes involved in various metabolic pathways, particularly in producing carboxylic acids, aromatic amino acids, nitrogen compounds, and polyamines, showed dramatic down-regulation at the early time point. Moreover, genes associated with transport systems localizing to transmembranes were down-regulated at both time points. Conclusion This is the first report of global change in the prominent cellular pathways in the Fusarium host containing FgV1-DK21. The significant increase in transcripts for transcription and translation machinery in fungal host cells seems to be related to virus replication. In addition, significant down-regulation of genes required for metabolism and transporting systems in a fungal host containing the virus appears to be related to the host defense mechanism and fungal virulence. Taken together

  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.

    , 7, 10, 14, 17, 21 and 24 days post infection (dpi). The pigs infected with the “Bor59” virus developed higher body temperature and more severe clinical symptoms compared to the other three groups, although the clinical signs in general were mild. The acute phase response was measured in serum...... samples as an objective indicator of infection. Acute phase protein C-reactive protein (CRP) showed an increase in levels in pigs infected with the Eastern European viruses with an earlier rise for Bor59 than for Ili6, both peaking at 10 dpi. In contrast, the CRP level did not increase significantly...... in neither the subtype 1 virus inoculated pigs nor the sham-inoculated controls. Acute phase protein haptoglobin showed a very early increase in Bor59 infected pigs, peaking at 3 dpi, while no increase was observed in Ili6 infected pigs. All of the virus inoculated pigs seroconverted, as measured by IPMA...

  19. Experimental infections of mice and guinea pigs with Haemophilus parasuis.

    Science.gov (United States)

    Morozumi, T; Hiramune, T; Kobayashi, K

    1982-01-01

    The pathogenicity of Haemophilus parasuis for mice and guinea pigs was examined. Mice were inoculated intraperitoneally with 2 X 10(7) to 2 X 10(9) organisms suspended in saline or in broth containing fresh yeast extract. Most of them survived after inoculation. Death occurred only in mice inoculated with 2 X 10(9) organisms suspended in broth. The recovery rate of H. parasuis from all the dead mice varied from 28.9% of the brains to 71.4% of the lungs. There were no lesions observed in any mouse, except one. Guinea pigs were inoculated intraperitoneally with 1 X 10(8) to 1.6 X 10(10) organisms suspended in saline. Many of them died after showing septicemia and serofibrinous serositis, which were associated with purulent leptomeningitis or meningoencephalitis in some of them. H. parasuis was recovered abundantly from many organs, including the brain, in the guinea pigs. It was also recovered from guinea pigs inoculated with 1.8 X 10(9) organisms by various routes. Serositis was observed in guinea pigs inoculated intramuscularly or intrapulmonarily. These results suggested that guinea pigs might be available for investigation of the pathogenicity of H. parasuis.

  20. Thymic Stromal Lymphopoietin Is Critical for Regulation of Proinflammatory Cytokine Response and Resistance to Experimental Trypanosoma congolense Infection

    Directory of Open Access Journals (Sweden)

    Chukwunonso Onyilagha

    2017-07-01

    Full Text Available African trypanosomiasis (sleeping sickness poses serious threat to human and animal health in sub-Saharan Africa. Because there is currently no vaccine for preventing this disease and available drugs are not safe, understanding the mechanisms that regulate resistance and/or susceptibility to the disease could reveal novel targets for effective disease therapy and prevention. Thymic stromal lymphopoietin (TSLP plays a critical role in driving Th2 immune response. Although susceptibility to experimental Trypanosoma congolense infection in mice is associated with excessive proinflammatory responses due in part to impaired Th2 response, the role of TSLP in resistance to African trypanosomiasis has not been well studied. Here, we investigated whether TSLP is critical for maintaining Th2 environment necessary for survival of T. congolense-infected mice. We observed an increased TSLP level in mice after infection with T. congolense, suggesting a role for this cytokine in resistance to the infection. Indeed, TSLPR−/− mice were more susceptible to T. congolense infection and died significantly earlier than their wild-type (WT controls. Interestingly, serum levels of IFN-γ and TNF-α and the frequency of IFN-γ- and TNF-α-producing CD4+ T cells in the spleens and liver were significantly higher in infected TSLPR−/− mice than in the WT control mice. Susceptibility was also associated with excessive M1 macrophage activation. Treatment of TSLPR−/− mice with anti-IFN-γ mAb during infection abolished their enhanced susceptibility to T. congolense infection. Collectively, our study shows that TSLP plays a critical role in resistance to T. congolense infection by dampening the production of proinflammatory cytokines and its associated M1 macrophage activation.

  1. High rate of transplacental infection and transmission of Neospora caninum following experimental challenge of cattle at day 210 of gestation

    Directory of Open Access Journals (Sweden)

    Benavides Julio

    2012-12-01

    Full Text Available Abstract In order to investigate the pathogenesis of neosporosis following a primary infection in late pregnancy, cattle were subcutaneously challenged with 5 × 108Neospora caninum (NC1 isolate tachyzoites at day 210 of gestation and serial necropsies were then carried out at 14, 28, 42 and 56 days post-infection (dpi. No abortions occurred and all the foetuses were viable at the time of euthanasia. There was a high rate of vertical transmission, as parasites were detected by immunohistochemical labelling and PCR in all the foetuses from 28 dpi. Focal necrotic lesions were observed in the placentomes of the placenta from 28 dpi and showed resolution during later time points, denoted by infiltration of inflammatory cells at 42 dpi and fibrosis at 56 dpi. Foetuses at 28 and 42 dpi showed scarce and isolated lesions which are unlikely to represent a threat to foetal viability. No lesions were observed in the foetuses at 14 or 56 dpi suggesting control of the infection and resolution of the lesions by maternal and foetal immune responses. Once infection was established, it could not be cleared from the host and vertical transmission of the parasite occurred in all infected hosts. Parasite was detected in the placenta at 28 dpi, while in previous experimental infections of cattle at day 70 and 140 of gestation using the same challenge model, it was already present at day 14 post infection. This suggests that a change in the maternal immune response plays a crucial role in limiting the initial infection during the last term of pregnancy.

  2. Growth of cyprinid herpesvirus 2 (CyHV-2) in cell culture and experimental infection of goldfish Carassius auratus.

    Science.gov (United States)

    Ito, Takafumi; Kurita, Jun; Ozaki, Akiyuki; Sano, Motohiko; Fukuda, Hideo; Ototake, Mitsuru

    2013-09-03

    Herpesviral haematopoietic necrosis has caused great economic damage to goldfish Carassius auratus aquaculture in Japan. The existence of cyprinid herpesvirus 2 (CyHV-2), the causative agent, has also been reported from several other countries. To prevent spread to other areas, basic virological information such as viral kinetics in infected fish is essential. Experimental infection trials using reliably prepared CyHV-2 for defining viral kinetics are difficult to carry out because successful and sustainable propagation of this virus in cell culture has previously been limited. Here we describe a method for sustainable propagation of CyHV-2 in cell culture, and the results of fish infection experiments using the propagated virus. We found that goldfish fin (GFF) cells and standard Ryukin Takafumi (SRTF) cells established from goldfish fin can be used for continuous propagation of CyHV-2. Experimental infections using 2 varieties of goldfish, Ryukin and Edonishiki, were performed with the virus passaged 7 times in GFF cells. In transmission experiments with water temperature at 20°C, cumulative mortality was 30% in Ryukin infected by immersion, and 90 and 100% in Edonishiki and Ryukin intraperitoneally injected with the virus, respectively. In an experiment carried out at 25°C, 90% of Edonishiki challenged by immersion died. PCR detection of viral DNA from the organs of infected fish showed that systemic infection occurs and also that the kidney is a main viral multiplication site. Moreover, CyHV-2 was successfully re-isolated in GFF cells from the dead fish.

  3. 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...... MICOTC of 8.0 mug/ml and only little effect was seen when the strain MICOTC was 4.0 mug/ml. This shows that it is valid to predict the treatment efficiency of OTC from in vitro data facing an outbreak of rainbow trout fry syndrome. The importance of doing susceptibility testing is emphasized...

  4. 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

  5. Local Cellular Immune Responses and Pathogenesis of Buruli Ulcer Lesions in the Experimental Mycobacterium Ulcerans Pig Infection Model.

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    Miriam Bolz

    2016-04-01

    Full Text Available Buruli ulcer is a neglected tropical disease of the skin that is caused by infection with Mycobacterium ulcerans. We recently established an experimental pig (Sus scrofa infection model for Buruli ulcer to investigate host-pathogen interactions, the efficacy of candidate vaccines and of new treatment options.Here we have used the model to study pathogenesis and early host-pathogen interactions in the affected porcine skin upon infection with mycolactone-producing and non-producing M. ulcerans strains. Histopathological analyses of nodular lesions in the porcine skin revealed that six weeks after infection with wild-type M. ulcerans bacteria extracellular acid fast bacilli were surrounded by distinct layers of neutrophils, macrophages and lymphocytes. Upon ulceration, the necrotic tissue containing the major bacterial burden was sloughing off, leading to the loss of most of the mycobacteria. Compared to wild-type M. ulcerans bacteria, toxin-deficient mutants caused an increased granulomatous cellular infiltration without massive tissue necrosis, and only smaller clusters of acid fast bacilli.In summary, the present study shows that the pathogenesis and early immune response to M. ulcerans infection in the pig is very well reflecting BU disease in humans, making the pig infection model an excellent tool for the profiling of new therapeutic and prophylactic interventions.

  6. 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

  7. Seasonality and circadian variation of microfilaremia in dogs experimentally infected with Dirofilaria immitis.

    Science.gov (United States)

    Lovis, Léonore; Grandjean, Mélanie; Overney, Laurence; Seewald, Wolfgang; Sager, Heinz

    2017-08-30

    Periodicity, the cyclical rise and fall in microfilaria (mff) numbers in the peripheral blood over time, is observed in many filarial infections. It is correlated with the necessity for these larval stages to be ingested by the blood feeding vector before they can be transmitted to a new vertebrate host. Microfilariae of the dog heartworm Dirofilaria immitis have been described to show periodicity, but the circadian pattern does not seem to be consistent. Most publications describe the lowest mff-concentrations in the peripheral blood in the early morning, while the highest counts occurred either in the afternoon, in the late evening or shortly after midnight. Sixteen dogs were experimentally infected with D. immitis isolates originating from Italy (one isolate, 14 dogs), and the USA (two isolates, one dog each). The dogs were housed indoors with a natural light source (windows) and heating that prevented temperature-drops below 20°C during winter. When patency was reached, blood samples were collected at weekly and monthly intervals over a period of up to 3 years, and at given hours of the day (morning, noon, evening) for the duration of one year in order to determine seasonal, as well as daily variations of microfilaremia. Despite the fact that the dogs were kept indoors, there was an apparent seasonality of the D. immitis-microfilaremia, with peaks in summer and 5-49-times lower counts in winter. This difference was statistically significant and the ratio remained constant over the years, regardless of the fact that the mff-counts increased from the first to the second year of patency. Since the temperature was kept constantly in a range between 20 to 26°C (with some single outliners in both directions) the climatic conditions may not explain this observation. Therefore, day length may be the most obvious reason for the seasonality in the given study set-up. Interestingly, the Italian D. immitis-isolate lost seasonality after three passages of experimental

  8. 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.

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

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    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

  10. Infecção experimental por Trypanosoma vivax em ovinos Experimental infection by Trypanosoma vivax in sheep

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    Jael Soares Batista

    2006-03-01

    Full Text Available O presente estudo teve por objetivo avaliar as alterações clínicas, hematológicas e patológicas em ovinos infectados experimentalmente com Trypanosoma vivax, utilizando-se um isolado proveniente de bovinos infectados naturalmente no município de Catolé do Rocha, Paraíba. Quatro ovinos da raça Santa Inês foram infectados por via intravenosa com 1ml de sangue contendo 1,85x10(5 tripomastigotas de T. vivax e outros quatro ovinos foram destinados ao grupo controle. A parasitemia e a temperatura foram determinadas diariamente durante 30 dias após a infecção (dpi e quinzenalmente dos 31 aos 90 dias. A cada 15 dias os animais foram pesados e realizados coletas de sangue para hemograma. Um ovino morreu aos 75 dpi, os demais animais do grupo infectado e do grupo controle foram sacrificados 90 dias após o início do experimento. T. vivax foi evidenciado a partir do 4º dpi em todos os ovinos infectados. A parasitemia foi constante até os 15 dias e irregular entre os 16 e 30 dias. Após o 30º dia não foram observados parasitas no sangue. Foi observada correlação linear positiva entre temperatura retal e parasitemia [Y=0,027x + 38,515; R²=0,9444 (PThis paper has the objective to report clinical signs, hematologic changes, and macroscopic and microscopic alterations in sheep infected experimentally with Trypanosoma vivax, isolated from an outbreak in cattle in the semiarid region of the state of Paraíba, northeastern Brazil. Four Santa Inês sheep were inoculated intravenously with 1ml of blood containing 1.85x10(5 trypomastigotes. Other 4 sheep were used as control. The presence of trypanosomes in the blood and the temperature were recorded daily during the first 30 days and fortnightly from day 31 to day 90 after infection. Also fortnightly, the sheep were weighed and blood samples were obtained for hematological analysis. One inoculated sheep died 75 days after inoculation. The other 3 inoculated and the 4 control sheep were killed 90

  11. 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.

  12. Rainbow trout surviving infections of viral haemorrhagic septicemia virus (VHSV) show lasting antibodies to recombinant G protein fragments

    DEFF Research Database (Denmark)

    Encinas, P.; Gomez-Casado, E.; Grandes, Fregeneda

    2011-01-01

    sera from trout infected with the homologous VHSV isolate but also with the VHSV-DK-201433 heterologous isolate, which had 13 amino acid changes. Sera from healthy trout and/or from trout surviving infectious haematopoietic necrosis virus (IHNV) infection, were used to calculate cut-off absorbances...... refinements of the frg-ELISA could allow detection of anti-VHSV trout Abs in natural outbreaks caused by different heterologous VHSV isolates. The homologous frg-ELISA method could be useful to follow G immunization attempts during vaccine development and/or to best understand the fish Ab response during VHSV...... infections. The viral frgs approach might also be used with other fish species and/or viruses....

  13. Experimental porcine rubulavirus (La Piedad-Michoacan virus) infection in pregnant gilts.

    Science.gov (United States)

    Hernández-Jáuregui, P; Ramírez Mendoza, H; Mercado García, C; Moreno-López, J; Kennedy, S

    2004-01-01

    Porcine rubulavirus (La Piedad-Michoacan virus) (PoRV-LPMV) is a member of the Paramyxoviridae family that causes encephalitis in young piglets and infertility in adult sows and boars. Infertility in sows naturally infected by PoRV-LPMV is characterized by an increased number of returns to oestrus, stillbirths and mummified fetuses. In this study, nine seronegative gilts were inoculated intranasally with the PAC-3 strain of PoRV-LPMV at week 6 or 10 of gestation. These animals were then killed at weeks 8 or 15 of gestation (seven gilts) or after natural parturition (two gilts). Four control gilts were mock-infected at gestation week 6 or 10 and killed between 2 and 4 weeks later. Gross lesions of focal congestion and haemorrhage were seen in the placenta and endometrium of one gilt infected at gestation week 6 and one infected at gestation week 10. PoRV-LPMV was isolated, at 2-6 weeks post-inoculation (pi), from lung, tonsils, ovary, placenta, uterus and lymph nodes of three of the gilts infected at gestation week 6 and at 2-3 weeks pi from lung, tonsil and ovary of two gilts infected at gestation week 10. Many of the fetuses of eight infected gilts were smaller than normal and had dermal ecchymoses. Dehydrated or mummified fetuses were present in six of the infected gilts but not in any control animal. PoRV-LPMV was isolated from brain, lung and liver of fetuses from two gilts infected at gestation week 6, and from two infected at gestation week 10. These results indicate that, after experimental infection, PoRV can replicate in tissues of seronegative pregnant gilts, cross the placenta, and cause fetal death and mummification.

  14. 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...

  15. Schmallenberg virus detection in bovine semen after experimental infection of bulls.

    NARCIS (Netherlands)

    Poel, van der W.H.M.; Parlevliet, J.M.; Verstraten, E.R.A.M.; Kooi, E.A.; Hakze-van der Honing, van der R.W.; Stockhofe-Zurwieden, N.

    2014-01-01

    To study Schmallenberg virus (SBV) excretion in bovine semen after experimental infection, two bulls were inoculated subcutaneously with a SBV isolate (1 ml Vero cell culture 106 TCID50). After inoculation (at day 0), semen was collected daily from both animals for 21 days and samples were tested

  16. Detection of infectious laryngotracheitis virus by real-time PCR in naturally and experimentally infected chickens.

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    Yan Zhao

    Full Text Available Infectious laryngotracheitis (ILT is an acute, highly contagious upper-respiratory infectious disease of chickens. In this study, a real-time PCR method was developed for fast and accurate detection and quantitation of ILTV DNA of chickens experimentally infected with ILTV strain LJS09 and naturally infected chickens. The detection lower limit of the assay was 10 copies of DNA. There were no cross reactions with the DNA and RNA of infectious bursal disease virus, chicken anemia virus, reticuloendotheliosis virus, avian reovirus, Newcastle disease virus, and Marek's disease virus. The real-time PCR was reproducible as the coefficients of variation of reproducibility of the intra-assay and the inter-assay were less than 2%. The real-time PCR was used to detect the levels of the ILTV DNA in the tissues of specific pathogen free (SPF chickens infected with ILTV at different times post infection. ILTV DNA was detected by real-time PCR in the heart, liver, spleen, lung, kidney, larynx, tongue, thymus, glandular stomach, duodenum, pancreatic gland, small intestine, large intestine, cecum, cecal tonsil, bursa of Fabricius, and brain of chickens in the infection group and the contact-exposure group. The sensitivity, specificity, and reproducibility of the ILTV real-time PCR assay revealed its suitability for detection and quantitation of ILTV in the samples from clinically and experimentally ILTV infected chickens.

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

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    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.

  18. Toxoplasma gondii detection and viability assays in ham legs and shoulders from experimentally infected pigs.

    Science.gov (United States)

    Gomez-Samblas, M; Vilchez, S; Racero, J C; Fuentes, M V; Osuna, A

    2016-09-01

    Epidemiological studies of toxoplasmosis show that infection in humans is mainly caused by the consumption of raw, undercooked or cured meat. Cured "Serrano" ham is a typical pork product from the Mediterranean area, highly valued for its flavour. The "Serrano" ham is prepared from pork meat and undergoes a process known as curing and a subsequent fermentation without thermal or smoking treatments. The viability of Toxoplasma gondii in hams and shoulders from experimentally infected pigs that have been subject to different curing processes has been studied in order to evaluate the best method to completely eliminate the viable protozoa. The different treatments include, i) freezing the legs and shoulders below -20 °C for 3 days before salting with marine salt, ii) salting the meat with marine salt and nitrites, iii) salting only with marine salt (traditional process) and iv) salting with marine salt and then freezing at -20 °C for 3 days after the curing period. The ham leg samples were cured for 7 months and the shoulder samples for 5 months. The presence of T. gondii in the different treatments was studied by a "magnetic-capture" method for the isolation of T. gondii DNA and a quantitative real-time PCR to estimate the T. gondii burden in the ham legs and shoulders. The infectivity capacity of T. gondii in positive samples was assayed by bioassays in mice and some physicochemical parameters, such as pH, water activity (aw) and salt content, were evaluated at the end of the curing time. In all the cases where the samples were frozen the T. gondii infectivity was eliminated. In samples in which the meat was salted in marine salt plus nitrites, the parasite viability remained for longer than in the traditional salting process. The methods described here could be useful for producers to guarantee the safety of their products. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Two clinical isolates of Mycoplasma hyosynoviae showed differing pattern of lameness and pathogen detection in experimentally challenged pigs.

    Science.gov (United States)

    Gomes-Neto, João Carlos; Raymond, Matthew; Bower, Leslie; Ramirez, Alejandro; Madson, Darin M; Strait, Erin L; Rosey, Everett L; Rapp-Gabrielson, Vicki J

    2016-12-30

    Mycoplasma (M.) hyosynoviae is known to colonize and cause disease in growing-finishing pigs. In this study, two clinical isolates of M. hyosynoviae were compared by inoculating cesarean-derived colostrum-deprived and specific-pathogen-free growing pigs. After intranasal or intravenous inoculation, the proportion and distribution pattern of clinical cases was compared in addition to the severity of lameness. Tonsils were found to be the primary site of colonization, while bacteremia was rarely detected prior to the observation of clinical signs. Regardless of the clinical isolate, route of inoculation, or volume of inocula, histopathological alterations and tissue invasion were detected in multiple joints, indicating an apparent lack of specific joint tropism. Acute disease was primarily observed 7 to 10 days post-inoculation. The variability in the severity of synovial microscopic lesions and pathogen detection in joint cavities suggests that the duration of joint infection may influence the diagnostic accuracy. In summary, these findings demonstrate that diagnosis of M. hyosynoviae-associated arthritis can be influenced by the clinical isolate, and provides a study platform to investigate the colonization and virulence potential of field isolates. This approach can be particularly relevant to auxiliate in surveillance and testing of therapeutic and/or vaccine candidates.

  20. Treatment efficacy and regulatory host responses in chronic experimental Schistosoma bovis infections in goats.

    Science.gov (United States)

    Monrad, J; Sörén, K; Johansen, M V; Lindberg, R; Ornbjerg, N

    2006-08-01

    The aim of this study was to elucidate the regulatory responses and the long-term effect of praziquantel treatment in chronically Schistosoma bovis-infected West African Dwarf goats. Forty-two goats were used and the design comprised a primary infection followed by treatment at week 13, challenge infection at week 36 and termination at week 52. Dependent variables included clinico-pathological data, worm numbers, faecal and tissue egg counts, and gross pathology of the liver. The results showed that primary infections remained suppressed for up to 52 weeks and, although challenge infections imposed on 36-week-old primary infections established fully, the impairment of their egg production capacity provided protection against clinico-pathological consequences measured by body weight and haemoglobin levels. The study also confirmed a high efficacy (97.7%) of praziquantel for treatment of S. bovis infection in goats and showed that anthelminthic removal of primary infections does not interfere with the ability of the goat to elicit a marked resistance to a subsequent challenge infection. Although treated goats had more fibrous scarring of livers than untreated goats, no negative effects of liver lesions were reflected in weight gains of treated goats. This study provides strong evidence for the beneficial effects of anthelminthic treatment of young domestic stock as an element of treatment and preventive programmes.

  1. 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

    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...... 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...

  2. Induced expression of the antimicrobial peptide melittin inhibits experimental infection by Mycoplasma gallisepticum in chickens.

    Science.gov (United States)

    Lazarev, Vassili N; Stipkovits, Laszlo; Biro, Judit; Miklodi, Dora; Shkarupeta, Marina M; Titova, Galina A; Akopian, Tatiana A; Govorun, Vadim M

    2004-05-01

    The in vivo action of the antimicrobial peptide melittin, expressed from a recombinant plasmid vector, on chickens experimentally infected with Mycoplasma gallisepticum was studied. The plasmid vector pBI/mel2/rtTA includes the melittin gene under the control of an inducible tetracycline-dependent human cytomegalovirus promoter and the gene coding for the trans-activation protein rtTA. Aerosol administration of the vector, followed by infecting the chickens with M. gallisepticum 1226, is shown to inhibit development of infection. The inhibitory action was confirmed by a complex of clinical, pathomorphological, histological and serological studies, and also by comparing the M. gallisepticum reisolation frequency from the respiratory tract and internal organs. The data suggest that plasmid vectors expressing genes of antimicrobial peptides can be considered as potential agents for the prevention and treatment of mycoplasma infections in poultry farming.

  3. The challenge of using experimental infectivity data in risk assessment for Ebola virus: why ecology may be important.

    Science.gov (United States)

    Gale, P; Simons, R R L; Horigan, V; Snary, E L; Fooks, A R; Drew, T W

    2016-01-01

    Analysis of published data shows that experimental passaging of Zaire ebolavirus (EBOV) in guinea pigs changes the risk of infection per plaque-forming unit (PFU), increasing infectivity to some species while decreasing infectivity to others. Thus, a PFU of monkey-adapted EBOV is 10(7) -fold more lethal to mice than a PFU adapted to guinea pigs. The first conclusion is that the infectivity of EBOV to humans may depend on the identity of the donor species itself and, on the basis of limited epidemiological data, the question is raised as to whether bat-adapted EBOV is less infectious to humans than nonhuman primate (NHP)-adapted EBOV. Wildlife species such as bats, duikers and NHPs are naturally infected by EBOV through different species giving rise to EBOV with different wildlife species-passage histories (heritages). Based on the ecology of these wildlife species, three broad 'types' of EBOV-infected bushmeat are postulated reflecting differences in the number of passages within a given species, and hence the degree of adaptation of the EBOV present. The second conclusion is that the prior species-transmission chain may affect the infectivity to humans per PFU for EBOV from individuals of the same species. This is supported by the finding that the related Marburg marburgvirus requires ten passages in mice to fully adapt. It is even possible that the evolutionary trajectory of EBOV could vary in individuals of the same species giving rise to variants which are more or less virulent to humans and that the probability of a given trajectory is related to the heritage. Overall the ecology of the donor species (e.g. dog or bushmeat species) at the level of the individual animal itself may determine the risk of infection per PFU to humans reflecting the heritage of the virus and may contribute to the sporadic nature of EBOV outbreaks. © 2015 Crown copyright. © 2015 Society for Applied Microbiology.

  4. IL-6 KO mice develop experimental amoebic liver infection with eosinophilia.

    Science.gov (United States)

    Estrada-Villaseñor, Eréndira; Morales-Montor, Jorge; Rodríguez-Dorantes, Mauricio; Ramos-Martínez, Espiridión; Néquiz-Avendaño, Mario; Ostoa-Saloma, Pedro

    2007-12-01

    Interleukin 6 (IL-6) is a multifunctional cytokine that regulates various aspects of the immune response, such as acute phase reaction and hematopoiesis, and is an important signal that coordinates activities of liver cells, macrophages, and lymphocytes. Amoebic liver lesions have been studied, usually in hamsters, due to the problem of abscess development in mice. We report here the development of an experimental amoebic liver abscess (ALA) model in mice deficient in IL-6. Axenically grown amoebae were injected directly into the livers of C57BL/6 wild type (WT) and IL-6 KO -/- mice; the abscesses produced were counted and the inflammatory process was examined on 5, 10, and 20 days postinfection. Our results showed that IL-6 KO -/- mice develop ALA, in contrast to the WT strain, which usually do not have signs of abscess or infection. Histological analysis of the abscesses showed extended inflammatory response, mainly mediated by eosinophils, which strongly infiltrate the abscess in IL-6 K -/- mice. The present results suggest that in mice, IL-6 could play a role in the resistance against ALA.

  5. 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.

  6. Experimental infection of Pacific oyster Crassostrea gigas spat by ostreid herpesvirus 1: demonstration of oyster spat susceptibility

    Directory of Open Access Journals (Sweden)

    Schikorski David

    2011-02-01

    Full Text Available Abstract In 2008 and 2009, acute mortalities occurred in France among Pacific cupped oyster, Crassostrea gigas, spat. Different hypothesis including the implication of environmental factors, toxic algae and/or pathogens have been explored. Diagnostic tests indicated that OsHV-1 including a particular genotype, termed OsHV-1 μVar, was detected in most of samples and especially in moribund oysters with the highlighting of virus particles looking like herpes viruses by TEM examination. In this study, an experimental protocol to reproduce OsHV-1 infection in laboratory conditions was developed. This protocol was based on the intramuscular injection of filtered (0.22 μm tissue homogenates prepared from naturally OsHV-1 infected spat collected on French coasts during mortality outbreaks in 2008. Results of the experimental trials showed that mortalities were induced after injection. Moreover, filtered tissue homogenates induced mortalities whereas the same tissue homogenates exposed to an ultraviolet (UV treatment did not induce any mortality suggesting that oyster spat mortalities require the presence of a UV sensitive agent. Furthermore, analysis of injected oyster spat revealed the detection of high amounts of OsHV-1 DNA by real-time quantitative PCR. Finally, TEM analysis demonstrated the presence of herpes virus particles. The developed protocol allowed to maintain sources of infective virus which can be useful for the development of further studies concerning the transmission and the development of OsHV-1 infection.

  7. Qualitative evaluation of selective tests for detection of Neospora hughesi antibodies in serum and cerebrospinal fluid of experimentally infected horses.

    Science.gov (United States)

    Packham, Andrea E; Conrad, Patricia A; Wilson, W David; Jeanes, Lisa V; Sverlow, Karen W; Gardner, Ian A; Daft, Barbara M; Marsh, Antoinette E; Blagburn, Byron L; Ferraro, Gregory L; Barr, Bradd C

    2002-12-01

    Neospora hughesi is a newly recognized protozoan pathogen in horses that causes a myeloencephalitis similar to Sarcocystis neurona. There are no validated serologic tests using the gold standard sera that are currently available to detect specific N. hughesi antibodies and, thus, no tests available to detect antemortem exposure or estimate seroprevalence in the horse. The objectives of the present study were to establish a bank of gold standard equine sera through experimental infections with N. hughesi and to assess several serologic tests for the detection of related protozoan antibodies. Seven horses were inoculated with N. hughesi tachyzoites, and 7 horses received uninfected cell culture material. The horses were monitored, and blood and cerebrospinal fluid were collected repeatedly over a 4-mo period. With the sera, 4 different serologic techniques were evaluated. including a whole-parasite lysate enzyme-linked immunosorbent assay (ELISA), a recombinant protein ELISA, a modified direct agglutination test, and an indirect fluorescent antibody test. Qualitative and quantitative evaluation of the results showed that the N. hughesi indirect fluorescent antibody test (IFAT) consistently discriminated between experimentally infected and noninfected horses, using a cutoff of 1:640. Sera from 3 naturally infected horses had titers >1:640. Cerebrospinal fluid in all but I infected horse had very low N. hughesi IFAT titers (<1:160), starting at postinoculation day 30.

  8. Toxoplasma gondii infection can induce retinal DNA damage:an experimental study

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    Nagwa Mostafa El-Sayed

    2014-06-01

    Full Text Available AIM: To detect whether Toxoplasma gondii (T. gondii infection of mice can induce retinal DNA damage.METHODS: A total of 20 laboratory-bred male Swiss albino mice were used and divided into four groups:control group (non-infected animals; T. gondiiinfected group; immunosuppressed infected group; and infected#$NLgroup treated with sulfadiazine and pyrimethamine. Mice eyes were collected 6wk post infection and retinas were obtained. Each retina was immediately processed for comet assay and the frequency of tailed nuclei (DNA damage was calculated. In addition, retinal DNA damage was revealed by various comet assay parameters that were provided by the image analysis software including tail length, percentage of DNA in the tail, percentage of tailed cells and tail moment.RESULTS: The obtained results showed that T. gondii infectioninduced a statistically significant increase in the frequency of tailed nuclei, tail length, percentage of DNA in the tail, and tail moment in mice retinal cells compared to the control group (which showed some degree of DNA damage. In immunosuppressed infected group, retinal DNA damage was severing and there wassignificant increase in various comet assay parameters compared to both control and infected groups. After treatment with sulfadiazine and pyrimethamine, retinal DNA damage decreased and all comet assay parameters showed a statistical significant decrease compared to infected groups.CONCLUSION: T. gondii infectioncan induce DNA damage in mice retinal cells.

  9. 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.

  10. 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.

  11. Alcoholic Fractions F5 and F6 from Withania somnifera Leaves Show a Potent Antileishmanial and Immunomodulatory Activities to Control Experimental Visceral Leishmaniasis.

    Science.gov (United States)

    Chandrasekaran, Sambamurthy; Veronica, Jalaja; Sundar, Shyam; Maurya, Radheshyam

    2017-01-01

    Visceral leishmaniasis (VL) causes fatal life-threatening disease, if left untreated. The current drugs have various limitations; hence, natural products from medicinal plants are being focused in search of new drugs to treat leishmaniasis. The aim of the present study was to evaluate the antileishmanial and immunomodulatory activities of F5 and F6 alcoholic fractions from Withania somnifera leaves and purified withaferin-A in Leishmania donovani-infected peritoneal macrophages and BALB/c mice. We observed that F5 (15 µg/mL), F6 (10 µg/mL), and withaferin-A (1.5 µM) reduce amastigote count in peritoneal macrophages and induce reactive oxygen species and significant decrease in IL-10 mRNA expression compared to control upon treatment. Subsequently, in vivo study mice were treated with F5 (25 and 50 mg/kg b.wt.), F6 (25 and 50 mg/kg b.wt.) orally, and withaferin-A (2 mg/kg b.wt.) intraperitoneally for 10 consecutive days and a drastic reduction in parasite burden in both spleen and liver were observed. The treatment resulted in the reduction in IL-10, IL-4, and TGF-β mRNA expression and a significant increase in IFN-γ/IL-10 expression ratio in the treated group compared to control. The humoral response of these alcoholic fractions and withaferin-A shows increased IgG2a levels when compared with IgG1 in treated mice. Taken together, our result concludes that withanolides in alcoholic fractions demonstrate a potent antileishmanial and immunomodulatory activities in experimental VL.

  12. Alcoholic Fractions F5 and F6 from Withania somnifera Leaves Show a Potent Antileishmanial and Immunomodulatory Activities to Control Experimental Visceral Leishmaniasis

    Directory of Open Access Journals (Sweden)

    Sambamurthy Chandrasekaran

    2017-05-01

    Full Text Available Visceral leishmaniasis (VL causes fatal life-threatening disease, if left untreated. The current drugs have various limitations; hence, natural products from medicinal plants are being focused in search of new drugs to treat leishmaniasis. The aim of the present study was to evaluate the antileishmanial and immunomodulatory activities of F5 and F6 alcoholic fractions from Withania somnifera leaves and purified withaferin-A in Leishmania donovani-infected peritoneal macrophages and BALB/c mice. We observed that F5 (15 µg/mL, F6 (10 µg/mL, and withaferin-A (1.5 µM reduce amastigote count in peritoneal macrophages and induce reactive oxygen species and significant decrease in IL-10 mRNA expression compared to control upon treatment. Subsequently, in vivo study mice were treated with F5 (25 and 50 mg/kg b.wt., F6 (25 and 50 mg/kg b.wt. orally, and withaferin-A (2 mg/kg b.wt. intraperitoneally for 10 consecutive days and a drastic reduction in parasite burden in both spleen and liver were observed. The treatment resulted in the reduction in IL-10, IL-4, and TGF-β mRNA expression and a significant increase in IFN-γ/IL-10 expression ratio in the treated group compared to control. The humoral response of these alcoholic fractions and withaferin-A shows increased IgG2a levels when compared with IgG1 in treated mice. Taken together, our result concludes that withanolides in alcoholic fractions demonstrate a potent antileishmanial and immunomodulatory activities in experimental VL.

  13. An experimental displacement and over 50 years of tag-recoveries show that monarch butterflies are not true navigators

    DEFF Research Database (Denmark)

    Mourtisen, Henrik; Derbyshirec, Rachael; Stalleickena, Julia

    2013-01-01

    Monarch butterflies (Danaus plexippus) breeding in eastern North America are famous for their annual fall migration to their overwintering grounds in Mexico. However, the mechanisms they use to successfully reach these sites remain poorly understood. Here, we test whether monarchs are true...... directionality of migration from north to south is largely because of the presence of geographic barriers that guide individuals toward overwintering sites. Our work suggests that monarchs breeding in eastern North America likely combine simple orientation mechanisms with geographic features that funnel them...... show that the directional concentration and the angular SD of recoveries from tagged monarchs largely conformed to two mathematical models describing the directional distribution of migrants expected under a vector-navigation strategy. A third analysis of tagged recoveries shows that the increasing...

  14. Large-scale experimental studies show unexpected amino acid effects on protein expression and solubility in vivo in E. coli

    Science.gov (United States)

    2011-01-01

    The biochemical and physical factors controlling protein expression level and solubility in vivo remain incompletely characterized. To gain insight into the primary sequence features influencing these outcomes, we performed statistical analyses of results from the high-throughput protein-production pipeline of the Northeast Structural Genomics Consortium. Proteins expressed in E. coli and consistently purified were scored independently for expression and solubility levels. These parameters nonetheless show a very strong positive correlation. We used logistic regressions to determine whether they are systematically influenced by fractional amino acid composition or several bulk sequence parameters including hydrophobicity, sidechain entropy, electrostatic charge, and predicted backbone disorder. Decreasing hydrophobicity correlates with higher expression and solubility levels, but this correlation apparently derives solely from the beneficial effect of three charged amino acids, at least for bacterial proteins. In fact, the three most hydrophobic residues showed very different correlations with solubility level. Leu showed the strongest negative correlation among amino acids, while Ile showed a slightly positive correlation in most data segments. Several other amino acids also had unexpected effects. Notably, Arg correlated with decreased expression and, most surprisingly, solubility of bacterial proteins, an effect only partially attributable to rare codons. However, rare codons did significantly reduce expression despite use of a codon-enhanced strain. Additional analyses suggest that positively but not negatively charged amino acids may reduce translation efficiency in E. coli irrespective of codon usage. While some observed effects may reflect indirect evolutionary correlations, others may reflect basic physicochemical phenomena. We used these results to construct and validate predictors of expression and solubility levels and overall protein usability, and we

  15. No evidence of horizontal infection in horses kept in close contact with dogs experimentally infected with canine influenza A virus (H3N8

    Directory of Open Access Journals (Sweden)

    Yamanaka Takashi

    2012-04-01

    Full Text Available Abstract Background Since equine influenza A virus (H3N8 was transmitted to dogs in the United States in 2004, the causative virus, which is called canine influenza A virus (CIV, has become widespread in dogs. To date, it has remained unclear whether or not CIV-infected dogs could transmit CIV to horses. To address this, we tested whether or not close contact between horses and dogs experimentally infected with CIV would result in its interspecies transmission. Methods Three pairs of animals consisting of a dog inoculated with CIV (108.3 egg infectious dose50/dog and a healthy horse were kept together in individual stalls for 15 consecutive days. During the study, all the dogs and horses were clinically observed. Virus titres in nasal swab extracts and serological responses were also evaluated. In addition, all the animals were subjected to a gross pathological examination after euthanasia. Results All three dogs inoculated with CIV exhibited clinical signs including, pyrexia, cough, nasal discharge, virus shedding and seroconversion. Gross pathology revealed lung consolidations in all the dogs, and Streptococcus equi subsp. zooepidemicus was isolated from the lesions. Meanwhile, none of the paired horses showed any clinical signs, virus shedding or seroconversion. Moreover, gross pathology revealed no lesions in the respiratory tracts including the lungs of the horses. Conclusions These findings may indicate that a single dog infected with CIV is not sufficient to constitute a source of CIV infection in horses.

  16. Schmallenberg virus infection in South American camelids: Field and experimental investigations.

    Science.gov (United States)

    Schulz, Claudia; Beer, Martin; Hoffmann, Bernd

    2015-11-18

    During the first epizootic wave of the novel, teratogenic Schmallenberg virus (SBV, Orthobunyavirus) in ruminants in Northern Europe, serological evidence of a previous SBV-infection demonstrated that South American camelids (SAC) are also susceptible to SBV. However, their potential role in SBV spread remains unknown. To investigate the prevalence and course of SBV-infection in SAC, a German field study and an animal trial with three llamas and three alpacas were conducted. From September 2012 to December 2013, 313 of 502 SAC (62.35%) were found SBV seropositive, but negative for SBV-RNA. The estimated between-district (94.23% of 52) and median within-district (71.43%) and herd (73.13%) SBV seroprevalence in German SAC was similar to the seroprevalence reported in cattle herds and sheep flocks at the time. An age of >1 year was found a statistically significant risk factor for SBV-infection, which could be explained by the spatio-temporal spread of SBV in Germany during the study period. No clinical signs or an increase of abortion and congenital malformation associated with SBV-infection in SAC were reported by the study participants. Similar to SBV-infected ruminants, SBV-RNAemia in experimentally SBV-infected SAC was detected for a short time between days 3 and 7 after infection (dpi), and seroconversion occurred between 9 and 21 dpi. Despite the similar virological and serological results, the lack of clinical signs and congenital malformation associated with SBV-infection suggests that SBV causes subclinical infection in SAC. However, their role as reservoirs in the spread of SBV has to be further investigated. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Persistence of viral RNA in the brain of experimentally infected mice with coxsackievirus B5

    OpenAIRE

    Sobotova Z.; Marosova L.; Badurova M.; Sojka M.; Borsanyiova M.; Stipalova D.; Bopegamage S.

    2011-01-01

    The aim of our study was to follow the persistence of viral RNA in selected organs of experimentally infected with coxsackievirus (CV) B5 strains from different sources such as a patient’s sample, an environmental sample and a prototype virus strain. Methods . CD-1 mice were infected with CVB5 strain Faulkner the prototype, CVB5 – isolate from treated sewage waste and isolate from patient’s stool sample both identified as CVB5. The viral RNA was detected by RT-PCR using enterovirus primers sp...

  18. Experimental infections with rifampicin-resistant Clostridium perfringens strains in broiler chickens using isolator facilities

    DEFF Research Database (Denmark)

    Pedersen, Karl; Bjerrum, Lotte; Nauerby, Birgitte

    2003-01-01

    Experimental infection studies were carried out on the ability of three Clostridium perfringens type A rifampicin-resistant strains to colonize the intestinal tract of broiler chickens kept in isolators from 1-day-old. Various doses of C. perfringens were given orally at 22 days, 9 days or at 1 day...... replaced by naturally occurring strains of C. perfringens in all groups but they persisted for considerably longer in chickens inoculated at 1-day-old or at 9 days than those at 22 days, indicating a possible resistance to colonization with increasing age. The findings emphasize the difficulties...... of establishing a reproducible model for infection with C. perfringens in broiler chickens....

  19. 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

  20. Early Results Show Reduced Infection Rate Using No-touch Technique for Expander/ADM Breast Reconstruction

    Directory of Open Access Journals (Sweden)

    Henry B. Wilson, MD, FACS

    2015-03-01

    Full Text Available Summary: Infection is a common complication of immediate breast reconstruction that often leads to device removal, a result emotionally devastating to the patient and frustrating for her surgeon. “No-touch” techniques have been used in other surgical disciplines and plastic surgery, but they have not been reported for breast reconstruction with tissue expanders or implants and acellular dermis. We report a novel technique of tissue expander and acellular dermis placement using no-touch principles with a self-retaining retractor system that holds promise to decrease infectious complications of breast reconstruction.

  1. Preclinical deposition of pathological prion protein in muscle of experimentally infected primates.

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    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.

  2. 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.

  3. Experimental Infections with Mycoplasma agalactiae Identify Key Factors Involved in Host-Colonization

    Science.gov (United States)

    Baranowski, Eric; Bergonier, Dominique; Sagné, Eveline; Hygonenq, Marie-Claude; Ronsin, Patricia; Berthelot, Xavier; Citti, Christine

    2014-01-01

    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. PMID:24699671

  4. Expression of circulating leucocytes before, during and after myiasis by Dermatobia hominis in experimentally infected rats.

    Science.gov (United States)

    Gonçalves, Jomara M; Pereira, Mônica C T; Evangelista, Luciene G; Leite, Antônio C R

    2007-01-01

    Expression of circulating white blood cells was investigated in rats (Rattus norvegicus) experimentally infected with larvae of Dermatobia hominis, the human bot fly. Leucocytes were counted prior to infection (control group) as well as at 6, 10, 15, 20 and 28 days post-infection (dpi) and at 7, 15, 30 and 60 days post-larval emergence (dple). Total leucocyte numbers did not differ markedly among the groups. Significant differences were registered when values from control and animals harboring each larval stage of D. hominis were compared; with crescent rank: L1-, L2-, control and L3-infected groups. Leucocyte numbers were significantly higher in the control, 15, 20 or 28 dpi groups than in the 6 dpi animals. Higher counts were observed in control, L2- or L3-infected rats than L1-infected animals. Neutrophils, eosinophils and both large and small lymphocytes were also counted and analyzed. Basophils and monocytes were insufficient in number to permit statistical studies. These results stimulate the continuity of the studies about the host-parasite relationship in the dermatobiosis.

  5. The effect of salinity on experimental infections of a Hematodinium sp. in blue crabs, Callinectes sapidus.

    Science.gov (United States)

    Coffey, Anna H; Li, Caiwen; Shields, Jeffrey D

    2012-06-01

    The parasitic dinoflagellate Hematodinium sp. parasitizes blue crabs along the Atlantic seaboard of the United States. Infections in blue crabs have only been reported from waters where salinity is >11 practical salinity units (psu). Blue crabs maintain a hyperosmotic internal concentration at low salinities (0-5 psu), roughly comparable to 24 psu, and should be capable of maintaining an infection in low-salinity waters even if Hematodinium spp. cells are intolerant of low salinities. We tested this notion by observing the effect of low salinity on the progression of disease in crabs experimentally infected with the parasite. Blue crabs were acclimated to 5 psu or 30 psu salinity treatments. They were inoculated with Hematodinium sp. and necropsied 3, 7, 10, and 15 days post-inoculation. The low-salinity treatment did not have an effect on the proliferation of Hematodinium sp. infections in blue crabs; moreover, a greater proportion of infections in crabs in the low-salinity treatment developed dinospore stages than did those in the high-salinity treatment, indicating that salinity may affect the development of the parasite. However, dinospores from in vitro cultures rapidly became inactive when held in salinities <15 psu. Our experiments indicate that Hematodinium spp. can develop in blue crabs at low salinities, but that the parasite is incapable of transmission in this environment, which explains the lack of natural infections in crabs at low salinities.

  6. Genotyping of Trypanosoma cruzi DTUs and Trypanosoma rangeli genetic groups in experimentally infected Rhodnius prolixus by PCR-RFLP.

    Science.gov (United States)

    Sá, Amanda R N; Dias, Greicy B M; Kimoto, Karen Y; Steindel, Mário; Grisard, Edmundo C; Toledo, Max Jean O; Gomes, Mônica L

    2016-04-01

    The specific detection and genetic typing of trypanosomes that infect humans, mammalian reservoirs, and vectors is crucial for diagnosis and epidemiology. We utilized a PCR-RFLP assay that targeted subunit II of cytochrome oxidase and 24Sα-rDNA to simultaneously detect and discriminate six Trypanosoma cruzi discrete typing units (DTUs) and two genetic groups of Trypanosoma rangeli (KP1+/KP1-) in intestinal contents of experimentally infected Rhodnius prolixus. The PCR assays showed that in 23 of 29 (79.4%) mixed infections with the six T. cruzi DTUs and mixed infections with individual DTUs and/or groups KP1+ and KP1-, both parasites were successfully detected. In six mixed infections that involved TcIII, the TcI, TcII, TcV, and TcVI DTUs predominated to the detriment of TcIII, indicating the selection of genetic groups. Interactions between different genetic groups and vectors may lead to genetic selection over TcIII. The elimination of this DTU by the immune system of the vector appears unlikely because TcIII was present in other mixed infections (TcIII/TcIV and TcIII/KP1+). Both molecular markers used in this study were sensitive and specific, demonstrating their usefulness in a wide geographical area where distinct genotypes of these two species are sympatric. Although the cellular and molecular mechanisms that are involved in parasite-vector interactions are still poorly understood, our results indicate a dynamic selection toward specific T. cruzi DTUs in R. prolixus during mixed genotype infections. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Expression of immune-related genes in rohu Labeo rohita (Hamilton) by experimental freshwater lice Argulus siamensis (Wilson) infection.

    Science.gov (United States)

    Saurabh, Shailesh; Mohanty, B R; Sahoo, P K

    2011-01-10

    The crustacean ectoparasite, Argulus poses one of the major threats to carp culture due to absence of any suitable control measure. The study was undertaken to determine the expression of immune-related genes in three major immunocompetent organs viz., kidney, skin and liver of rohu (Labeo rohita) during experimental freshwater lice Argulus siamensis infection. Results showed that the expression of TLR 22-like, lysozyme G and β2-microglobulin genes in kidney was significantly (P ≤ 0.05) down-regulated in lice-infected fish. On the other hand, no significant difference (P>0.05) in CXCa, lysozyme C, TNFα and complement component 3 (C3) expression was found between uninfected control and different degrees of lice infected fish. In the skin, the expression of TLR 22-like and TNFα genes were significantly up-regulated whereas that of C3 was significantly (P ≤ 0.05) down-regulated in lice-infected fish with respect to control fish. The expression of CXCa, lysozyme C and transferrin was not detected in the skin samples of fish. In the liver, the expression of CXCa, lysozyme G, β2-microglobulin and transferrin was significantly (P≤0.05) up-regulated in lice-infected fish with respect to control fish whereas expression of C3 was significantly (P ≤ 0.05) down-regulated in lice-infected fish. The expression of TLR 22-like, lysozyme C, TNFα genes was not detected in the liver samples of fish. This study indicates that majority of the genes showed down-regulation in kidney tissue whereas up-regulation in liver and skin tissues except C3 in Argulus-infected fish. We show that infection with this parasite irrespective of intensity can also result in immune gene expression changes in tissues situated away from the site of parasite attachment and feeding. The information obtained here could be useful towards understanding the susceptibility of rohu to argulosis and mechanisms involved in protection of rohu to ectoparasitic infections, which is causing immense economic

  8. A novel life cycle modeling system for Ebola virus shows a genome length-dependent role of VP24 in virus infectivity.

    Science.gov (United States)

    Watt, Ari; Moukambi, Felicien; Banadyga, Logan; Groseth, Allison; Callison, Julie; Herwig, Astrid; Ebihara, Hideki; Feldmann, Heinz; Hoenen, Thomas

    2014-09-01

    Work with infectious Ebola viruses is restricted to biosafety level 4 (BSL4) laboratories, presenting a significant barrier for studying these viruses. Life cycle modeling systems, including minigenome systems and transcription- and replication-competent virus-like particle (trVLP) systems, allow modeling of the virus life cycle under BSL2 conditions; however, all current systems model only certain aspects of the virus life cycle, rely on plasmid-based viral protein expression, and have been used to model only single infectious cycles. We have developed a novel life cycle modeling system allowing continuous passaging of infectious trVLPs containing a tetracistronic minigenome that encodes a reporter and the viral proteins VP40, VP24, and GP1,2. This system is ideally suited for studying morphogenesis, budding, and entry, in addition to genome replication and transcription. Importantly, the specific infectivity of trVLPs in this system was ∼ 500-fold higher than that in previous systems. Using this system for functional studies of VP24, we showed that, contrary to previous reports, VP24 only very modestly inhibits genome replication and transcription when expressed in a regulated fashion, which we confirmed using infectious Ebola viruses. Interestingly, we also discovered a genome length-dependent effect of VP24 on particle infectivity, which was previously undetected due to the short length of monocistronic minigenomes and which is due at least partially to a previously unknown function of VP24 in RNA packaging. Based on our findings, we propose a model for the function of VP24 that reconciles all currently available data regarding the role of VP24 in nucleocapsid assembly as well as genome replication and transcription. Ebola viruses cause severe hemorrhagic fevers in humans, with no countermeasures currently being available, and must be studied in maximum-containment laboratories. Only a few of these laboratories exist worldwide, limiting our ability to study

  9. Physiological changes in Rhipicephalus microplus (Acari: Ixodidae) experimentally infected with entomopathogenic fungi.

    Science.gov (United States)

    Angelo, Isabele C; Tunholi-Alves, Vinícius M; Tunholi, Victor M; Perinotto, Wendell M S; Gôlo, Patrícia S; Camargo, Mariana G; Quinelato, Simone; Pinheiro, Jairo; Bittencourt, Vânia R E P

    2015-01-01

    Carbohydrate metabolism plays an important role in the physiology and maintenance of energy stores within living organisms. However, when organisms are exposed to adverse physiological conditions, such as during pathogenic infection, these organisms begin to use alternative substrates (proteins and lipids) for energy production. This paper studied the carbohydrate metabolism of Rhipicephalus microplus after infection with Beauveria bassiana and Metarhizium anisopliae. The parameters evaluated were glucose concentration, enzymatic activities of lactate dehydrogenase (LDH), alanine aminostransferase (ALT) and aspartate aminostransferase (AST), amounts of uric acid and urea in the hemolymph, and amount of glycogen in the fat body. The results showed changes in nitrogenous products, including an increase in the amount of urea detected 48 h after infection with both fungi. The enzymatic activities of LDH, ALT, and AST were increased after infection. The amount of glucose was increased 24 h after infection with B. bassiana and was reduced 48 h after infection with both fungi. The amount of glycogen in the fat body was reduced at different times of infection with both fungi. These results demonstrate, for the first time, the changes in carbohydrate metabolism of R. microplus after infection with M. anisopliae and B. bassiana and contribute to a better understanding of this host-parasite relationship. Together with knowledge of diseases that affect these ticks and their susceptibility to entomopathogens, an understanding of tick physiology will be necessary for the effective implementation of current biological control methods and will assist in the discovery of new methods to control this ectoparasite.

  10. Marginal vitamin A deficiency in pigs experimentally infected with Trichuris suis

    DEFF Research Database (Denmark)

    Pedersen, S; Saeed, I; Jensen, S K

    2001-01-01

    The development of an experimental model for marginal vitamin A deficiency in humans is of major interest, enabling the elucidation of possible interactions with helminth infections. We established a useful experimental model for human vitamin A deficiency in young pigs; deficiency was induced...... through a depletion method encompassing both sow and offspring. We report on a 2 x 2 study in which 18-week-old vitamin A deficient pigs and vitamin A sufficient littermates were infected with both of the intestinal nematodes Trichuris suis and Ascaris suum and followed for 14 weeks through 32 weeks...... of age. Forty-nine pigs were followed with respect to bodyweight, liver biopsies and blood samples for retinol concentration and faecal samples for parasite eggs and worms. Liver and serum concentrations of vitamin A were significantly diminished in the vitamin A deficient (VAD) group as compared...

  11. 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.

  12. 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.

  13. Metabolic and histopathological profile of Rattus norvegicus (Wistar) experimentally infected by Angiostrongylus cantonensis (Chen, 1935).

    Science.gov (United States)

    Garcia, Juberlan Silva; Lúcio, Camila dos Santos; Bonfim, Tatiane Cristina dos Santos; Junior, Arnaldo Maldonado; Tunholi, Victor Menezes; Tunholi-Alves, Vinícius Menezes; Mota, Esther Maria; Simões, Raquel de Oliveira; Santana, André Campos; Hooper, Cleber; Pinheiro, Jairo; Bóia, Marcio Neves

    2014-02-01

    Eosinophilic meningitis is a disease characterized by increased eosinophils in the cerebrospinal fluid (CSF), which is the most commonly caused by invasion of the central nervous system by helminths, as occurs in Angiostrongylus cantonensis infections. The rodent Rattus norvegicus is the definitive natural host and humans act as accidental hosts and can become infected by eating raw or undercooked snails or food contaminated with infective L3 larvae. Recently in Brazil there have been four cases of eosinophilic meningitis due to ingestion of infected Achatina fulica. To evaluate biochemical and histopathological changes caused by this parasite, R. norvegicus were experimentally infected with 100 L3 larvae of A. cantonensis. After the anesthetic procedure, serum from the rodents was collected from the inferior vena cava for evaluation of the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALKP), gamma-glutamyl transferase (GGT), total protein and its fractions. During the necropsy, the liver was collected and weighed. Then a 1-g fragment was extracted from the major lobe to quantify the hepatic glycogen and fragment remainder was taken from the same lobe and fixed in Milloning's formalin for histopathological examination. Additionally, helminths were collected from the brain and lungs of the rodents. The activities of AST, ALT, ALKP and GGT in the serum and hepatic glycogen increased in response to infection, while the levels of globulin and total protein increased only in the eighth week of infection and there was a reduction in the levels of serum glucose. Albumin and bilirubin concentrations remained stable during the experiment. Infection with A. cantonensis caused metabolic and histopathological changes in the rodents. This study can contribute to a better understanding of the relationship between A. cantonensis and R. norvegicus. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Macrophage activation associated with chronic murine cytomegalovirus infection results in more severe experimental choroidal neovascularization.

    Directory of Open Access Journals (Sweden)

    Scott W Cousins

    Full Text Available The neovascular (wet form of age-related macular degeneration (AMD leads to vision loss due to choroidal neovascularization (CNV. Since macrophages are important in CNV development, and cytomegalovirus (CMV-specific IgG serum titers in patients with wet AMD are elevated, we hypothesized that chronic CMV infection contributes to wet AMD, possibly by pro-angiogenic macrophage activation. This hypothesis was tested using an established mouse model of experimental CNV. At 6 days, 6 weeks, or 12 weeks after infection with murine CMV (MCMV, laser-induced CNV was performed, and CNV severity was determined 4 weeks later by analysis of choroidal flatmounts. Although all MCMV-infected mice exhibited more severe CNV when compared with control mice, the most severe CNV developed in mice with chronic infection, a time when MCMV-specific gene sequences could not be detected within choroidal tissues. Splenic macrophages collected from mice with chronic MCMV infection, however, expressed significantly greater levels of TNF-α, COX-2, MMP-9, and, most significantly, VEGF transcripts by quantitative RT-PCR assay when compared to splenic macrophages from control mice. Direct MCMV infection of monolayers of IC-21 mouse macrophages confirmed significant stimulation of VEGF mRNA and VEGF protein as determined by quantitative RT-PCR assay, ELISA, and immunostaining. Stimulation of VEGF production in vivo and in vitro was sensitive to the antiviral ganciclovir. These studies suggest that chronic CMV infection may serve as a heretofore unrecognized risk factor in the pathogenesis of wet AMD. One mechanism by which chronic CMV infection might promote increased CNV severity is via stimulation of macrophages to make pro-angiogenic factors (VEGF, an outcome that requires active virus replication.

  15. Quantification of Pasteurella multocida in experimentally infected pigs using a real-time PCR assay.

    Science.gov (United States)

    Tocqueville, V; Kempf, I; Paboeuf, F; Marois-Créhan, C

    2017-06-01

    The aim of the study was to quantify Pasteurella multocida in experimentally infected pigs using a new qPCR assay based on the sodA gene and validated with 35 P. multocida strains, including strains isolated from pigs with pneumonia, clinically healthy pigs (nasal cavities), and human infections. The specificity of the test was verified with a collection of 60 strains of bacterial species other than P. multocida. The estimated detection threshold was 10 genome equivalents per microliter. The amplification efficiency and value of the correlation coefficients were 95.5% (±3.5%) and 0.995 (±0.005), respectively. Analysis of P. multocida suspensions in Buffered Peptone Water Broth and of samples prepared from lungs experimentally spiked with P. multocida revealed detection thresholds of 1.4CFU/μl and 8.4CFU/μl, respectively. In live pigs, experimentally-infected, approximately 10(5), 10(7) and 10(8)genomeequivalents/ml of P. multocida DNA was detected on Day 8 post-infection in the nasal cavities, tonsils and trachea samples, respectively. In dead pigs, approximatively 10(7)genomeequivalents/ml of P. multocida DNA was detected in the lung tissue with pneumonia. The qPCR assay's diagnostic specificity and sensitivity were 100% and 96%, respectively. This new qPCR assay should be a very useful tool for controlling enzootic pneumonia and studying the dynamics of infections in pig herds. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. 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.

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

    Science.gov (United States)

    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.

  18. 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

    was attributed to broiler chickens and a minor part to isolators, whereas infection trials did not affect the total variance. The results showed that pooled samples within isolators had lower c.f.u./g compared to the arithmetic mean of the individual samples. There was a significant correlation between faecal c...... 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...

  19. Population dynamics of the minute intestinal trematode Haplorchis pumilio following experimental infection of young dogs

    DEFF Research Database (Denmark)

    Nissen, Sofie; Nguyen, Lan Anh; Thamsborg, Stig Milan

    2011-01-01

    to have the highest intensity of infection and contribute the most to the contamination of the environment with FZT eggs in the Nam Dinh province - a highly endemic area for FZTs. Given the free roaming and fish-eating behaviour of many dogs in rural Vietnam controlling the infection in dogs represents......Fishborne zoonotic trematodes (FZT) are highly prevalent in Southeast Asia. Recent studies on domestic animal’s role in the transmission of FZT in Northern Vietnam found that the most prevalent FZT was Haplorchis pumilio. The importance of dogs, cats and pigs was assessed, and dogs were found...... a major challenge. In particular knowledge is needed on the importance of the dog as reservoir to make evidence-based recommendations for control of FZT. On this background, we conducted an experimental infection in dogs with H. pumilio to elucidate population dynamics and host reactions. Eight household...

  20. 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.

  1. [Experimental infection of goats with Schistosoma bovis and S. curassoni: comparative pathogenic effects].

    Science.gov (United States)

    Labbo, R; Boulanger, D; Brémond, P; Chippaux, J P

    2007-03-01

    Specific mortality and morbidity have been quantified in goats experimentally infected with Schistosoma bovis or S. curassoni strains from Niger. The study involved nine animals followed during 380 days after infection with, respectively, 1,800 or 2,400 cercariae. S. bovis was significatively more pathogenic than S. curossoni in terms of mortality, weight loss and packed cell volume decrease. In addition, the intensity of clinical symptoms was significatively and positively correlated to the levels of fecal egg excretion. Compared to non-infected controls, a growth differential of, respectively, 1,600 and 880 grams per month should incite to consider S. bovis and S. curassoni as parasites of serious economical impact in sahelian countries.

  2. 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.

  3. Nelfinavir and lopinavir impair Trypanosoma cruzi trypomastigote infection in mammalian host cells and show anti-amastigote activity.

    Science.gov (United States)

    Sangenito, Leandro S; d'Avila-Levy, Claudia M; Branquinha, Marta H; Santos, André L S

    2016-12-01

    There is an urgent need to implement new strategies and to search for new chemotherapeutic targets to combat Chagas' disease. In this context, repositioning of clinically approved drugs appears as a viable tool to combat this and several other neglected pathologies. An example is the use of aspartic peptidase inhibitors (PIs) currently applied in human immunodeficiency virus (HIV) treatment against different infectious agents. Therefore, the main objective of this work was to verify the effects of the HIV-PIs nelfinavir and lopinavir against Trypanosoma cruzi using in vitro models of infection. Cytotoxicity assays with LLC-MK 2 epithelial cells and RAW macrophages allowed an evaluation of the effects of HIV-PIs on the interaction between trypomastigotes and these cells as well as the survival of intracellular amastigotes. Pre-treatment of trypomastigotes with nelfinavir and lopinavir inhibited the association index with LLC-MK 2 cells and RAW macrophages in a dose- and time-dependent manner. In addition, nelfinavir and lopinavir also significantly reduced the number of intracellular amastigotes in both mammalian cell lineages, particularly when administered in daily doses. Both compounds had no effect on nitric oxide production in infected RAW macrophages. These results open the possibility for the use of HIV-PIs as a tangible alternative in the treatment of Chagas' disease. However, the main mechanism of action of nelfinavir and lopinavir has yet to be elucidated, and more studies using in vivo models must be conducted. Copyright © 2016 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

  4. The Healing Effect of Licorice on Pseudomonas aeruginosa Infected Burn Wounds in Experimental Rat Model

    OpenAIRE

    Tanideh, Nader; Rokhsari, Pedram; Mehrabani, Davood; Mohammadi Samani, Soleiman; Sabet Sarvestani, Fatemeh; Ashraf, Mohammad Javad; Koohi Hosseinabadi, Omid; Shamsian, Shahram; AHMADI, Nasrollah

    2014-01-01

    BACKGROUND Burn is still one of the most devastating injuries in emergency medicine while improvements in wound healing knowledge and technology have resulted into development of new dressings. This study was undertaken to evaluate the healing effect of licorice in Pseudomonas aeruginosa infected burn wounds of experimental rat model. METHODS One hundred and twenty female Sprague-Dawley rats were randomly allocated to 4 equal groups. Group A received silver sulfadiazine ointment, Group B rece...

  5. Treatment of pigs experimentally infected with Mycoplasma hyopneumoniae, Pasteurella multocida, and Actinobacillus pleuropneumoniae with various antibiotics.

    OpenAIRE

    Stipkovits, L.; Miller, D; Glavits, R; Fodor, L; Burch, D

    2001-01-01

    The authors have performed a comparative study of the efficacy of various in-feed medications for the treatment of 5- to 6-week-old specific pathogen-free (SPF) piglets experimentally infected on day 1 with Mycoplasma hyopneumoniae, on day 8 with Pasteurella multocida (serotype A), and on day 15 with Actinobacillus pleuropneumoniae (serotype 2). The treatment started on day 9 and continued for 12 consecutive days, then the piglets were euthanized for examination of macroscopic, histologic, an...

  6. Lethal effect of oxamniquine and praziquantel on mice experimentally infected with Schistosoma mansoni

    OpenAIRE

    Sonia Maria A.F. Tonelli; Eugênio M.A. Goulart; Edward Tonelli; Paulo Marcos Zech Coelho

    1995-01-01

    Lethality caused by administration of oxamniquine and praziquantel to mice infected with Schistosoma mansoni, and their respective controls (uninfected), has been studied. As the results indicate, the infected animals clearly showed higher mortality rates when praziquantel was used. Surprisingly, it may be noted that exactly the contrary occurs in relation to the use of oxamniquine, inasmuch as marked higher mortality rates were seen in the control animals (uninfected). These observations lea...

  7. Experimental basis for the clinical epidemiology of fungal infections. A review.

    Science.gov (United States)

    Schaffner, A

    1989-10-01

    Based on the concept that the agents of deep fungal infections can be divided into primary pathogens and opportunists the experimental basis for the clinical epidemiology of mycoses is outlined. Kinetics of experimental infections with opportunists and primary pathogens discriminate between the two fungal categories. Natural resistance eliminates opportunists and prevents the establishment of progressive infection in the normal host. Primary pathogens call upon mechanisms of adoptive cell mediated immunity for their control. Therefore athymic mice which are not more susceptible to opportunists than control mice, cannot control infection with primary pathogens. In order to induce comparable overwhelming opportunistic mycoses with reasonable challenge doses, non-specific phagocytic resistance has to be eliminated. In agreement with in vivo studies, in vitro studies of the susceptibility of fungi to killing by phagocytes point out, that the susceptibility of the tissue phase of fungi to killing by "immunologically unarmed" phagocytes discriminates between opportunists and primary pathogens. In order to restrain primary pathogenic fungi, phagocytes have also in vitro to call upon adoptive, T cell-dependent immune mechanisms, which appear superfluous for control of opportunists. This difference explains the discrepant opportunistic proclivities of the two fungal categories. Patients with defective phagocytic defenses are prone to opportunistic mycoses, while deficient cell mediated immunity results in a greater vulnerability to primary pathogens.

  8. Semen variables of sheep (Ovis aries) experimentally infected with Toxoplasma gondii.

    Science.gov (United States)

    Lopes, W D Z; Costa, A J; Souza, F A; Rodrigues, J D F; Costa, G H N; Soares, V E; Silva, G S

    2009-04-01

    The influence of Toxoplasma gondii on semen variables and sperm morphology of sheep was evaluated in eight reproductive males distributed into three experimental groups: GI, three sheep inoculated with 2.0x10(5) of P strain oocytes; GII, three sheep infected with 1.0x10(6) of RH strain tachyzoites and; GIII two control sheep. Clinical (rectal temperature, cardiac and respiratory frequencies), parasite and serology exams (IIF) were realized. Sperm variables (volume, motility, vigor and concentration) and semen morphology for each sheep were also evaluated. Thus, semen and blood collections were assessed on post-inoculation days (PIDs)-1,3,5,7,11,14 and weekly thereafter up to PID 70. Clinical alterations were observed (hypothermia and anorexia) in infected sheep from groups GI and GII. Parasitic outbreaks were detected in five sheep. All the infected sheep produced antibodies against T. gondii from PID 5 onwards, reaching a peak of 4096 and 8192 for group GI and GII sheep, respectively. Differences (P<0.05) were observed regarding the ejaculate volume between the inoculated groups (oocytes and tachyzoites) and control. Even though experimental toxoplasmic infection resulted in clinical symptomology in the inoculated sheep, the minimal alterations in sperm pathologies could not be directly attributed to T. gondii.

  9. Modeling of EBV Infection and Antibody Responses in Kenyan Infants With Different Levels of Malaria Exposure Shows Maternal Antibody Decay is a Major Determinant of Early EBV Infection.

    Science.gov (United States)

    Reynaldi, Arnold; Schlub, Timothy E; Piriou, Erwan; Ogolla, Sidney; Sumba, Odada P; Moormann, Ann M; Rochford, Rosemary; Davenport, Miles P

    2016-11-01

    The combination of Epstein-Barr virus (EBV) infection and high malaria exposure are risk factors for endemic Burkitt lymphoma, and evidence suggests that infants in regions of high malaria exposure have earlier EBV infection and increased EBV reactivation. In this study we analyzed the longitudinal antibody response to EBV in Kenyan infants with different levels of malaria exposure. We found that high malaria exposure was associated with a faster decline of maternally derived immunoglobulin G antibody to both the EBV viral capsid antigen and EBV nuclear antigen, followed by a more rapid rise in antibody response to EBV antigens in children from the high-malaria-transmission region. We also observed the long-term persistence of anti-viral capsid antigen immunoglobulin M responses in children from the high-malaria region. More rapid decay of maternal antibodies was a major predictor of EBV infection outcome, because decay predicted time to EBV DNA detection, independent of high or low malaria exposure. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  10. Protein profile of lambs experimentally infected with Haemonchus contortus and supplemented with selenium and copper.

    Science.gov (United States)

    Fausto, Guilherme Costa; Pivoto, Felipe Lamberti; Costa, Márcio Machado; dos Anjos Lopes, Sônia Terezinha; França, Raqueli Teresinha; Molento, Marcelo Beltrão; Minervino, Antonio Humberto Hamad; da Rocha, João Batista Teixeira; Leal, Marta Lizandra do Rêgo

    2014-08-05

    Gastrointestinal nematodes cause significant economic losses in the sheep industry, with frequent reports of anthelmintic resistance. Therefore, alternative methods to control these parasites are necessary. Thus, the aim of the present study was to assess the effect of treatment with selenium and copper on the protein profile of sheep that were experimentally infected with Haemonchus contortus. Twenty-eight lambs were experimentally infected with H. contortus and divided into four experimental groups as follow: G1--untreated animals; G2--treated with sodium selenite; G3--treated with copper; G4--treated with sodium selenite and copper. The serum protein, body weight and egg count per gram of feces (EPG) were assessed at the baseline and after 20, 40, 60 and 80 days. The parasite burden was assessed 80 days after the beginning of the experiment. Higher levels of total protein and gamma globulin were observed in the lambs treated with sodium selenite and copper on D80. Copper acted as a growth promoter. The copper-supplemented groups exhibited higher daily and total weight gain. The association of selenium and copper altered the protein profile of sheep. Copper and selenium supplementation reduced EPG and worm burden at the end of the experiment. To the best of our knowledge, this is the first study to demonstrate the positive effect of the combined parenteral supplementation of Se and Cu on H. contortus infection. This injectable supplementation could be used as an auxiliary method to control H. contortus in sheep.

  11. Histopathological changes in the kidneys of vertebrate hosts infected naturally and experimentally with Paratanaisia bragai (Trematoda, Digenea).

    Science.gov (United States)

    Xavier, Vanessa Barreto; Oliveira-Menezes, Aleksandra; dos Santos, Marcos Antônio José; Amato, Suzana Bencke; Torres, Eduardo José Lopes; Pinheiro, Jairo; Brandolini, Solange Viana Paschoal Blanco

    2015-01-01

    Paratanaisia bragai is a trematode parasite that reaches sexual maturity in the kidney collecting ducts of domesticated and wild fowl and whose intermediate hosts are the snails Subulina octona and Leptinaria unilamellata. There are some discrepancies in descriptions of the pathology of this parasite in bird kidneys. Therefore, the purpose of this study was to analyze the kidneys of rock pigeons (Columba livia) naturally infected and of chickens (Gallus gallus) experimentally infected with Paratanaisia bragai, by means of macroscopic observation and by light and scanning electron microscopy. Both bird species showed significantly dilated collecting ducts. In addition, lymphocyte infiltration was observed in the kidneys of C. livia and metaplasia in the epithelial lining of the kidney collecting ducts of G. gallus.

  12. 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.

  13. Preliminary Results Indicate That Inactivated Vaccine against Paratuberculosis Could Modify the Course of Experimental Mycobacterium bovis Infection in Calves

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    Miriam Serrano

    2017-10-01

    Full Text Available Although paratuberculosis (PTB vaccination has been recognized as an effective tool to control the disease, its use has been limited in countries undergoing bovine tuberculosis (bTB eradication programs because of its interference with the diagnostic techniques. Due to this restraint, little is known about the effect of vaccinating against PTB on the progression of bTB infection. To assess this topic, an experimental infection was carried out including the following three groups of five calves each: non-vaccinated infected with Mycobacterium bovis (NVI, vaccinated against PTB infected with M. bovis (VI, and vaccinated against PTB non-infected (VNI. The level of infection attending to pathological and bacteriological parameters was evaluated at necropsy in collected tissue samples. Infection was confirmed in all challenged animals being the lung and thoracic regions most affected for all studied parameters. The VI group presented 15.62% less gross lesions in the thoracic region than the NVI, although no significant differences were found. Only one vaccinated animal presented gross lesions in the lung, compared to three non-vaccinated calves. NVI animals showed an average of 1.8 lung lobes with gross lesions whereas in the vaccinated group the average number of affected lobes was 0.2, representing an 89% reduction. Significant differences were not found, although a tendency was observed (p = 0.126. Pathological and culture scores showed the same tendency. Vaccination induced a 71.42 and 60% reduction in lesion and culture scores in the lung as well as a 23.75 and 26.66% decline, respectively, in the thoracic region. The VI group showed lower positivity in the rest of the areas for all measured criteria except for the head. In order to reinforce our results, further research on a larger sample size is needed, but the results from this study suggest that PTB vaccination could confer certain degree of protection against bTB infection, supporting

  14. Effects of atmospheric ammonia on young pigs experimentally infected with Ascaris suum

    Energy Technology Data Exchange (ETDEWEB)

    Drummond, J.G.; Curtis, S.E.; Simon, J.; Norton, H.W.

    1981-06-01

    Effects of atmospheric ammonia at 69.4 mg/m3 (100 ppm) on productive performance and respiratory tract health of young pigs (starting body weight averaged 7.5 kg) experimentally infected with Ascaris suum (50,000 embryonated ova administered by gavage when pigs were 5 weeks of age) were studied in 5 trials of 4 weeks each (when pigs were 5 to 9 weeks of age). Effects of atmospheric-ammonia exposure and ascarid infection on growth were additive. Compared with controls, percentage reductions in average daily gain were 32%, 28%, and 61% for ammonia-exposed, ascarid-infected, and combined ammonia plus ascarid groups, respectively. Ammonia exposure or ascarid infection alone depressed feed disappearance by 18%. Effects of the 2 factors were additive, resulting in a 35% reduction in feed disappearance. Pigs exposed to the combined factors had an average gain/feed ratio of 0.518, which was less than that of control pigs (0.546), but was greater than that of pigs exposed to atmospheric ammonia (0.489) or pigs infected with ascarids (0.501) alone. Liver scarring, due to larval migration, was not affected by ammonia exposure. Larval migration through the respiratory tract was not confirmed histopathologically in pigs killed 4 weeks after inoculation. A supplementary experiment was conducted which demonstrated that residual evidence of previous pulmonary larval migration was present 2 weeks after inoculation.

  15. Mucosal Immune Responses of Mice Experimentally Infected with Pygidiopsis summa (Trematoda: Heterophyidae)

    Science.gov (United States)

    Chai, Jong-Yil; Park, Young-Jin; Park, Jae-Hwan; Jung, Bong-Kwang

    2014-01-01

    Mucosal immune responses against Pygidiopsis summa (Trematoda: Heterophyidae) infection were studied in ICR mice. Experimental groups consisted of group 1 (uninfected controls), group 2 (infection with 200 metacercariae), and group 3 (immunosuppression with Depo-Medrol and infection with 200 metacercariae). Worms were recovered in the small intestine at days 1, 3, 5, and 7 post-infection (PI). Intestinal intraepithelial lymphocytes (IEL), mast cells, and goblet cells were counted in intestinal tissue sections stained with Giemsa, astra-blue, and periodic acid-Schiff, respectively. Mucosal IgA levels were measured by ELISA. Expulsion of P. summa from the mouse intestine began to occur from days 3-5 PI which sustained until day 7 PI. The worm expulsion was positively correlated with proliferation of IEL, mast cells, goblet cells, and increase of IgA, although in the case of mast cells significant increase was seen only at day 7 PI. Immunosuppression suppressed all these immune effectors and inhibited worm reduction in the intestine until day 7 PI. The results suggested that various immune effectors which include IEL, goblet cells, mast cells, and IgA play roles in regulating the intestinal mucosal immunity of ICR mice against P. summa infection. PMID:24623878

  16. Galectin-3: A Friend but Not a Foe during Trypanosoma cruzi Experimental Infection

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    Aline A. da Silva

    2017-11-01

    Full Text Available Trypanosoma cruzi interacts with host cells, including cardiomyocytes, and induces the production of cytokines, chemokines, metalloproteinases, and glycan-binding proteins. Among the glycan-binding proteins is Galectin-3 (Gal-3, which is upregulated after T. cruzi infection. Gal-3 is a member of the lectin family with affinity for β-galactose containing molecules; it can be found in both the nucleus and the cytoplasm and can be either membrane-associated or secreted. This lectin is involved in several immunoregulatory and parasite infection process. Here, we explored the consequences of Gal-3 deficiency during acute and chronic T. cruzi experimental infection. Our results demonstrated that lack of Gal-3 enhanced in vitro replication of intracellular parasites, increased in vivo systemic parasitaemia, and reduced leukocyte recruitment. Moreover, we observed decreased secretion of pro-inflammatory cytokines in spleen and heart of infected Gal-3 knockout mice. Lack of Gal-3 also led to elevated mast cell recruitment and fibrosis of heart tissue. In conclusion, galectin-3 expression plays a pivotal role in controlling T. cruzi infection, preventing heart damage and fibrosis.

  17. Cardiac plexus of dogs experimentally infected with Trypanosoma cruzi: inflammatory lesions and quantitative studies

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    Marcelo V. Caliari

    1995-03-01

    Full Text Available Qualitative and quantitative aspects of the superficial and profound cardiac plexus of dogs experimentally infected with Be-62 and Be-78 strains of Trypanosoma cruzi were studied. Animals were autopsied in the acute phase of infection. The inflammatory process, lesions and number of parasites were more intense and frequent in animals infected with the Be-78 strain than in those infected with Be-62. Despite this, no statistically significant differences could be found between the number of neuron bodies in the ganglia of infected and control dogs.Foi realizado estudo qualitativo e quantitativo dos plexos cardíacos superficiais e profundos em cães inoculados com o Trypanosoma cruzi das cepas Be-62 e Be-78 e sacrificados na fase aguda. O processo inflamatório, as lesões e o parasitismo dos plexos foram mais intensos e frequentes nos animais inoculados com a cepa Be-78 do que naqueles inoculados com a cepa Be- 62. Apesar deste fato, não foi verificada diferença estatisticamente significativa entre o número de corpos de neurônio por gânglio dos animais chagásicos e os controles.

  18. Testing sex ratio theory with the malaria parasite Plasmodium mexicanum in natural and experimental infections.

    Science.gov (United States)

    Neal, Allison T; Schall, Jos J

    2014-04-01

    The malaria parasite (Plasmodium) life history accords well with the assumptions of local mate competition (LMC) of sex ratio theory. Within a single meal of the blood-feeding vector, sexually dimorphic gametocyte cells produce gametes (females produce one, males several) that mate and undergo sexual recombination. The theory posits several factors drive the Plasmodium sex ratio: male fecundity (gametes/male gametocyte), number and relative abundance of parasite clones, and gametocyte density. We measured these traits for the lizard malaria parasite, Plasmodium mexicanum, with a large sample of natural infections and infections from experiments that manipulated clonal diversity. Sex ratio in single-clone infections was slightly female-biased, but matched predictions of theory for this low-fecundity species. Sex ratio was less female-biased in clonally diverse infections as predicted by LMC for the experimental, but not natural infections. Gametocyte density was not positively related to sex ratio. These results are explained by the P. mexicanum life history of naturally low clonal diversity and high gametocyte production. This is the first study of a natural malaria system that examines all traits relevant to LMC in individual vertebrate hosts and suggests a striking example of sex ratio theory having significance for human public health. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  19. Experimental Infection of Rabbits with Rabbit and Genotypes 1 and 4 Hepatitis E Viruses

    Science.gov (United States)

    Ma, Hongxia; Zheng, Lin; Liu, Yunbo; Zhao, Chenyan; Harrison, Tim J.; Ma, Yuyuan; Sun, Shuhua; Zhang, Jingang; Wang, Youchun

    2010-01-01

    Background A recent study provided evidence that farmed rabbits in China harbor a novel hepatitis E virus (HEV) genotype. Although the rabbit HEV isolate had 77–79% nucleotide identity to the mammalian HEV genotypes 1 to 4, their genomic organization is very similar. Since rabbits are used widely experimentally, including as models of infection, we investigated whether they constitute an appropriate animal model for human HEV infection. Methods Forty-two SPF rabbits were divided randomly into eleven groups and inoculated with six different isolates of rabbit HEV, two different doses of a second-passage rabbit HEV, and with genotype 1 and 4 HEV. Sera and feces were collected weekly after inoculation. HEV antigen, RNA, antibody and alanine aminotransferase in sera and HEV RNA in feces were detected. The liver samples were collected during necropsy subject to histopathological examination. Findings Rabbits inoculated with rabbit HEV became infected with HEV, with viremia, fecal virus shedding and high serum levels of viral antigens, and developed hepatitis, with elevation of the liver enzyme, ALT. The severity of disease corresponded to the infectious dose (genome equivalents), with the most severe hepatic disease caused by strain GDC54-18. However, only two of nine rabbits infected with HEV genotype 4, and none infected with genotype 1, developed hepatitis although six of nine rabbits inoculated with the genotype 1 HEV and in all rabbits inoculated with the genotype 4 HEV seroconverted to be positive for anti-HEV IgG antibody by 14 weeks post-inoculation. Conclusions These data indicate that rabbits are an appropriate model for rabbit HEV infection but are not likely to be useful for the study of human HEV. The rabbit HEV infection of rabbits may provide an appropriate parallel animal model to study HEV pathogenesis. PMID:20161794

  20. Experimental infection of rabbits with rabbit and genotypes 1 and 4 hepatitis E viruses.

    Science.gov (United States)

    Ma, Hongxia; Zheng, Lin; Liu, Yunbo; Zhao, Chenyan; Harrison, Tim J; Ma, Yuyuan; Sun, Shuhua; Zhang, Jingang; Wang, Youchun

    2010-02-11

    A recent study provided evidence that farmed rabbits in China harbor a novel hepatitis E virus (HEV) genotype. Although the rabbit HEV isolate had 77-79% nucleotide identity to the mammalian HEV genotypes 1 to 4, their genomic organization is very similar. Since rabbits are used widely experimentally, including as models of infection, we investigated whether they constitute an appropriate animal model for human HEV infection. Forty-two SPF rabbits were divided randomly into eleven groups and inoculated with six different isolates of rabbit HEV, two different doses of a second-passage rabbit HEV, and with genotype 1 and 4 HEV. Sera and feces were collected weekly after inoculation. HEV antigen, RNA, antibody and alanine aminotransferase in sera and HEV RNA in feces were detected. The liver samples were collected during necropsy subject to histopathological examination. Rabbits inoculated with rabbit HEV became infected with HEV, with viremia, fecal virus shedding and high serum levels of viral antigens, and developed hepatitis, with elevation of the liver enzyme, ALT. The severity of disease corresponded to the infectious dose (genome equivalents), with the most severe hepatic disease caused by strain GDC54-18. However, only two of nine rabbits infected with HEV genotype 4, and none infected with genotype 1, developed hepatitis although six of nine rabbits inoculated with the genotype 1 HEV and in all rabbits inoculated with the genotype 4 HEV seroconverted to be positive for anti-HEV IgG antibody by 14 weeks post-inoculation. These data indicate that rabbits are an appropriate model for rabbit HEV infection but are not likely to be useful for the study of human HEV. The rabbit HEV infection of rabbits may provide an appropriate parallel animal model to study HEV pathogenesis.

  1. Experimental infection of rabbits with rabbit and genotypes 1 and 4 hepatitis E viruses.

    Directory of Open Access Journals (Sweden)

    Hongxia Ma

    Full Text Available BACKGROUND: A recent study provided evidence that farmed rabbits in China harbor a novel hepatitis E virus (HEV genotype. Although the rabbit HEV isolate had 77-79% nucleotide identity to the mammalian HEV genotypes 1 to 4, their genomic organization is very similar. Since rabbits are used widely experimentally, including as models of infection, we investigated whether they constitute an appropriate animal model for human HEV infection. METHODS: Forty-two SPF rabbits were divided randomly into eleven groups and inoculated with six different isolates of rabbit HEV, two different doses of a second-passage rabbit HEV, and with genotype 1 and 4 HEV. Sera and feces were collected weekly after inoculation. HEV antigen, RNA, antibody and alanine aminotransferase in sera and HEV RNA in feces were detected. The liver samples were collected during necropsy subject to histopathological examination. FINDINGS: Rabbits inoculated with rabbit HEV became infected with HEV, with viremia, fecal virus shedding and high serum levels of viral antigens, and developed hepatitis, with elevation of the liver enzyme, ALT. The severity of disease corresponded to the infectious dose (genome equivalents, with the most severe hepatic disease caused by strain GDC54-18. However, only two of nine rabbits infected with HEV genotype 4, and none infected with genotype 1, developed hepatitis although six of nine rabbits inoculated with the genotype 1 HEV and in all rabbits inoculated with the genotype 4 HEV seroconverted to be positive for anti-HEV IgG antibody by 14 weeks post-inoculation. CONCLUSIONS: These data indicate that rabbits are an appropriate model for rabbit HEV infection but are not likely to be useful for the study of human HEV. The rabbit HEV infection of rabbits may provide an appropriate parallel animal model to study HEV pathogenesis.

  2. The effectiveness of domestic cook on inactivation of murine norovirus in experimentally infected Manila clams (Ruditapes philippinarum).

    Science.gov (United States)

    Toffan, A; Brutti, A; De Pasquale, A; Cappellozza, E; Pascoli, F; Cigarini, M; Di Rocco, M; Terregino, C; Arcangeli, G

    2014-01-01

    The aim of this work was to evaluate the efficacy of domestic cooking in inactivating Manila clams experimentally infected with murine norovirus (MNV). A cooking pan was modified to enable electronic temperature probes to be positioned to record both flesh and environment temperature. Manila clams were infected with 10(4) TCID 50% ml(-1) of MNV. The infected whole-in-shell clams, divided into three replicates, were cooked on an electric stove, and groups of nine clams were removed from the pan at fixed intervals. Pools of three digestive glands were examined by virus isolation to ascertain residual viral load. Results showed that 10 min of cooking by a traditional domestic method at a temperature close to 100°C, for at least 2 min, can completely devitalize the MNV in infected clams. This is generally the time needed for the majority of valves to open up. At present, it is highly recommended to label all lagoon products as 'requiring cooking before consumption', but no specifications are given on how long and at what temperature they should be cooked. Our results can provide the consumer with useful indications on how to cook clams to prevent any risk of foodborne illness. © 2013 The Society for Applied Microbiology.

  3. IL-6 is Upregulated in Late-Stage Disease in Monkeys Experimentally Infected with Trypanosoma brucei rhodesiense

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    Dawn Nyawira Maranga

    2013-01-01

    Full Text Available The management of human African trypanosomiasis (HAT is constrained by lack of simple-to-use diagnostic, staging, and treatment tools. The search for novel biomarkers is, therefore, essential in the fight against HAT. The current study aimed at investigating the potential of IL-6 as an adjunct parameter for HAT stage determination in vervet monkey model. Four adult vervet monkeys (Chlorocebus aethiops were experimentally infected with Trypanosoma brucei rhodesiense and treated subcuratively at 28 days after infection (dpi to induce late stage disease. Three noninfected monkeys formed the control group. Cerebrospinal fluid (CSF and blood samples were obtained at weekly intervals and assessed for various biological parameters. A typical HAT-like infection was observed. The late stage was characterized by significant (P<0.05 elevation of CSF IL-6, white blood cell count, and total protein starting 35 dpi with peak levels of these parameters coinciding with relapse parasitaemia. Brain immunohistochemical staining revealed an increase in brain glial fibrillary acidic protein expression indicative of reactive astrogliosis in infected animals which were euthanized in late-stage disease. The elevation of IL-6 in CSF which accompanied other HAT biomarkers indicates onset of parasite neuroinvasion and show potential for use as an adjunct late-stage disease biomarker in the Rhodesian sleeping sickness.

  4. IL-6 is Upregulated in Late-Stage Disease in Monkeys Experimentally Infected with Trypanosoma brucei rhodesiense

    Science.gov (United States)

    Nyawira Maranga, Dawn; Kagira, John Maina; Kinyanjui, Christopher Kariuki; Muturi Karanja, Simon; Wangari Maina, Naomi; Ngotho, Maina

    2013-01-01

    The management of human African trypanosomiasis (HAT) is constrained by lack of simple-to-use diagnostic, staging, and treatment tools. The search for novel biomarkers is, therefore, essential in the fight against HAT. The current study aimed at investigating the potential of IL-6 as an adjunct parameter for HAT stage determination in vervet monkey model. Four adult vervet monkeys (Chlorocebus aethiops) were experimentally infected with Trypanosoma brucei rhodesiense and treated subcuratively at 28 days after infection (dpi) to induce late stage disease. Three noninfected monkeys formed the control group. Cerebrospinal fluid (CSF) and blood samples were obtained at weekly intervals and assessed for various biological parameters. A typical HAT-like infection was observed. The late stage was characterized by significant (P < 0.05) elevation of CSF IL-6, white blood cell count, and total protein starting 35 dpi with peak levels of these parameters coinciding with relapse parasitaemia. Brain immunohistochemical staining revealed an increase in brain glial fibrillary acidic protein expression indicative of reactive astrogliosis in infected animals which were euthanized in late-stage disease. The elevation of IL-6 in CSF which accompanied other HAT biomarkers indicates onset of parasite neuroinvasion and show potential for use as an adjunct late-stage disease biomarker in the Rhodesian sleeping sickness. PMID:24194772

  5. The effect of experimental streptococcus infection in myocarditis on some biochemical and inflammatory markers in albino rats.

    Science.gov (United States)

    Kholoud, S R; Iman, M K A; Rasha, E H; Soha, S S A

    2013-12-01

    Myocarditis is an uncommon disease that presents with a wide range of symptoms in children and adults. It is histologically characterized by varying degrees of myocardialnecrosis, edema and cellular infiltration myocardial inflammation is a nonspecificresponse to many triggers such as bacterial infection, cardio toxic agents, ormechanical injury. This study was carried out to investigate the experimental Streptococcus faecalis induction of myocarditis and its effect on some blood parameters, inflammatory markers and histopathological changes in male albino rats. Rats were infected by intraperitoneal injection of 10 8 CFU/ml of Streptococcus faecalis and sacrificed after one, two and seven days post infection. Biochemical analyses of blood were carried out to investigate the serum biomarkers of inflammation, liver function tests, cardiac enzymes & kidney function tests. All biochemical analyses showed statistically significant increase in the measured parameters due to bacterial infections except for blood urea which appear to be normal. A significant positive correlation was observed between lactate dehydrogenase enzyme (LDH) with creatinine (r =0.778, P<0.01). In the 7 days group, there were significant positive correlations between aspartate aminotransferase (AST) and alanine aminotransferase (ALT) (r=0.675, P<0.05), erythrocyte sedimentation rate (ESR) with Urea (r=0.659, P<0.05) and alkaline phosphatase (ALP) with C-reactive protein (CRP) (r=0.765, p<0.01). Many of these biomarkers will provide important new insights into pathophysiology and aid in the diagnosis and management of cardiovascular patients.

  6. Characterization of the porcine transferrin gene (TF) and its association with disease severity following an experimental Actinobacillus pleuropneumoniae infection.

    Science.gov (United States)

    Daniłowicz, E; Martinez-Arias, R; Dolf, G; Singh, M; Probst, I; Tümmler, B; Höltig, D; Waldmann, K-H; Gerlach, G-F; Stanke, F; Leeb, T

    2010-08-01

    Transferrin (TF)-mediated provision of iron is essential for a productive infection by many bacterial pathogens, and iron-depletion of TF is a first line defence against bacterial infections. Therefore, the transferrin (TF) gene can be considered a candidate gene for disease resistance. We obtained the complete DNA sequence of the porcine TF gene, which spans 40 kb and contains 17 exons. We identified polymorphisms on a panel of 10 different pig breeds. Comparative intra- and interbreed sequence analysis revealed 62 polymorphisms in the TF gene including one microsatellite. Ten polymorphisms were located in the coding sequence of the TF gene. Four SNPs (c.902A>T, c.980G>A, c.1417A>G, c.1810A>C) were predicted to cause amino acid exchanges (p.Lys301Ile, p.Arg327Lys, p.Lys473Glu, p.Asn604His). We performed association analyses using six selected TF markers and 116 pigs experimentally infected with Actinobacillus pleuropneumoniae serotype 7. The analysis showed breed-specific TF allele frequencies. In German Landrace, we found evidence for a possible association of the severity of A. pleuropneumoniae infection with TF genotypes.

  7. [Genotyping and evaluation of infection dynamics in a Colombian isolate of Leptospira santarosai in hamster as an experimental model].

    Science.gov (United States)

    Agudelo-Flórez, Piedad; Durango, Harold; Aranzazu, Diego; Rodas, Juan David; Travi, Bruno

    2014-01-01

    Is necessary to develop models for the study of leptospirosis. To genotype a Colombian strain of Leptospira isolated from a human with Weil´s syndrome and to evaluate its infection dynamics in the hamster experimental model. Genotyping was performed by amplification and sequence analysis of the rrs 16S and lipL32 genes. The median lethal dose was determined in intraperitoneally inoculated hamsters. The patterns of clinical chemistry, the duration of leptospiremia, leptospiruria and pathological findings were studied and compared in the same animal model infected with L. interrogans (Fiocruz L1-130). Molecular typing revealed that the isolate corresponded to the pathogenic species L. santarosai, which was recovered from hamsters´ kidneys and lungs and detected by lipL32 PCR from day 3 post-infection in these organs. There was a marked increase of C-reactive protein in animals at day 5 post-infection (3.25 mg/dl; normal value: 0.3 mg/dl) with decreases by day 18 (2.60 mg/dl: normal value: 0.8 mg/dl). Biomarkers of urea showed changes consistent with possible renal acute failure (day 5 post-infection: 49.01 mg/dl and day 18 post-infection: 53.71 mg/dl). Histopathological changes included interstitial pneumonia with varying degrees of hemorrhage and interstitial nephritis. The pathogenic species L. santarosai was identified in Colombia. Its pathogenicity as determined by tropism to lung and kidney was comparable to that of L. interrogans Fiocruz L1-130, well known for its virulence and pulmonar tropism. The biological aspects studied here had never before been evaluated in an autochthonous isolate.

  8. Mild Illness during Outbreak of Shiga Toxin−Producing Escherichia coli O157 Infections Associated with Agricultural Show, Australia

    Science.gov (United States)

    Stafford, Russell J.; Jennison, Amy V.; Bennett, Sonya M.; Bell, Robert J.; Doyle, Christine J.; Young, Jeannette R.; Vlack, Susan A.; Titmus, Paul; El Saadi, Debra; Jarvinen, Kari A.J.; Coward, Patricia; Barrett, Janine; Staples, Megan; Graham, Rikki M.A.; Smith, Helen V.; Lambert, Stephen B.

    2017-01-01

    During a large outbreak of Shiga toxin−producing Escherichia coli illness associated with an agricultural show in Australia, we used whole-genome sequencing to detect an IS1203v insertion in the Shiga toxin 2c subunit A gene of Shiga toxin−producing E. coli. Our study showed that clinical illness was mild, and hemolytic uremic syndrome was not detected. PMID:28930030

  9. Oxidative Stress in Wild Boars Naturally and Experimentally Infected with Mycobacterium bovis.

    Directory of Open Access Journals (Sweden)

    Diana Gassó

    Full Text Available Reactive oxygen and nitrogen species (ROS-RNS are important defence substances involved in the immune response against pathogens. An excessive increase in ROS-RNS, however, can damage the organism causing oxidative stress (OS. The organism is able to neutralise OS by the production of antioxidant enzymes (AE; hence, tissue damage is the result of an imbalance between oxidant and antioxidant status. Though some work has been carried out in humans, there is a lack of information about the oxidant/antioxidant status in the presence of tuberculosis (TB in wild reservoirs. In the Mediterranean Basin, wild boar (Sus scrofa is the main reservoir of TB. Wild boar showing severe TB have an increased risk to Mycobacterium spp. shedding, leading to pathogen spreading and persistence. If OS is greater in these individuals, oxidant/antioxidant balance in TB-affected boars could be used as a biomarker of disease severity. The present work had a two-fold objective: i to study the effects of bovine TB on different OS biomarkers (namely superoxide dismutase (SOD, catalasa (CAT, glutathione peroxidase (GPX, glutathione reductase (GR and thiobarbituric acid reactive substances (TBARS in wild boar experimentally challenged with Mycobacterium bovis, and ii to explore the role of body weight, sex, population and season in explaining the observed variability of OS indicators in two populations of free-ranging wild boar where TB is common. For the first objective, a partial least squares regression (PLSR approach was used whereas, recursive partitioning with regression tree models (RTM were applied for the second. A negative relationship between antioxidant enzymes and bovine TB (the more severe lesions, the lower the concentration of antioxidant biomarkers was observed in experimentally infected animals. The final PLSR model retained the GPX, SOD and GR biomarkers and showed that 17.6% of the observed variability of antioxidant capacity was significantly correlated

  10. Cell-mediated immune response to Leishmania chagasi experimental infection of BALB/c immunosuppressed mice

    Directory of Open Access Journals (Sweden)

    JG Machado

    2010-01-01

    Full Text Available Leishmaniasis, a zoonosis of worldwide distribution, presents a significant impact on immunosupressed patients. This study aimed to evaluate Leishmania chagasi infection in BALB/c mice immunosuppressed with dexamethasone. Spleen cells stimulated or not with L. chagasi were cultured for cytokine quantification (IFN-γ, IL-2, IL-4 and IL-10 by sandwich ELISA. Parasite loads in the spleen and liver were determined by means of culture microtitration. Immunosuppressed groups showed statistically lower spleen weight and CD4-cell percentage in blood on the day of infection and produced Th1 and Th2 cytokines on other days of the study. The other infected groups, weather immunosupressed or not, also produced Th1 and Th2 cytokines. Parasite loads in the spleen and liver were not statistically different among the groups. It was concluded that L. chagasi infection was not affected by dexamethasone-induced immunosuppression, probably due the reversible effect of the treatment.

  11. Antibiotic embedded absorbable prosthesis for prevention of surgical mesh infection: experimental study in rats.

    Science.gov (United States)

    Suárez-Grau, J M; Morales-Conde, S; González Galán, V; Martín Cartes, J A; Docobo Durantez, F; Padillo Ruiz, F J

    2015-04-01

    Ventral hernias are a common problem in a general surgery and hernioplasty is an integral part of a general surgeon's practice. The use of prosthetic material has drastically reduced the risk of recurrence, but has introduced additional potential complications such as surgical wound infections, adhesion formation, graft rejection, etc. The development of a wound infection in a hernia that is repaired with a prosthetic material is a grave complication, often requiring removal of the prosthesis. This experimental study examined efficacy of completely absorbable, hydrophilic, PGA-TMC (polyglycolic acid-trimethylene carbonate) prosthesis impregnated with antibiotic for reduction of infectious complications. Antibiotic-impregnated PGA-TMC prostheses were placed intraperitoneally in 90 Wistar white rats that were randomized and distributed into four groups. Group 0 (23 rats): there were placed PGA-TMC prosthesis without antibiotic impregnation (control group). Group 1 (25 rats): meshes were placed and infected later with 1 × 10(8) UFC of S. aureus/1 ml/2 cm(2) (Staphylococcus aureus ATCC 6538 American Type Culture Collection, Rockville, MD). Group 2 (21 rats): cefazolin-impregnated prostheses were placed (1 g × 100 ml, at the rate of 1 ml/cm(2) of prosthesis) and were subsequently infected with the same bacterial inoculate. Group 3 (21 rats): cefazolin-impregnated prostheses with double quantity of cefazolin and infected. A week later these animals were killed and specimens were extracted for bacterial quantification and histological studies. Evident decrease of bacterial colonization was observed in series 2 and 3 [the ones impregnated with cefazolin, in comparison with the group 1 (infected without previous antibiotic impregnation)] with statistically significant results (p prosthesis when placing it in contact with intraabdominal viscera. However, cefazolin impregnation of the mesh has reduced an adhesion formation, mostly when the infection reached a

  12. The pathogen Batrachochytrium dendrobatidis disturbs the frog skin microbiome during a natural epidemic and experimental infection.

    Science.gov (United States)

    Jani, Andrea J; Briggs, Cheryl J

    2014-11-25

    Symbiotic microbial communities may interact with infectious pathogens sharing a common host. The microbiome may limit pathogen infection or, conversely, an invading pathogen can disturb the microbiome. Documentation of such relationships during naturally occurring disease outbreaks is rare, and identifying causal links from field observations is difficult. This study documented the effects of an amphibian skin pathogen of global conservation concern [the chytrid fungus Batrachochytrium dendrobatidis (Bd)] on the skin-associated bacterial microbiome of the endangered frog, Rana sierrae, using a combination of population surveys and laboratory experiments. We examined covariation of pathogen infection and bacterial microbiome composition in wild frogs, demonstrating a strong and consistent correlation between Bd infection load and bacterial community composition in multiple R. sierrae populations. Despite the correlation between Bd infection load and bacterial community composition, we observed 100% mortality of postmetamorphic frogs during a Bd epizootic, suggesting that the relationship between Bd and bacterial communities was not linked to variation in resistance to mortal disease and that Bd infection altered bacterial communities. In a controlled experiment, Bd infection significantly altered the R. sierrae microbiome, demonstrating a causal relationship. The response of microbial communities to Bd infection was remarkably consistent: Several bacterial taxa showed the same response to Bd infection across multiple field populations and the laboratory experiment, indicating a somewhat predictable interaction between Bd and the microbiome. The laboratory experiment demonstrates that Bd infection causes changes to amphibian skin bacterial communities, whereas the laboratory and field results together strongly support Bd disturbance as a driver of bacterial community change during natural disease dynamics.

  13. Different genotypes of Trypanosoma cruzi produce distinctive placental environment genetic response in chronic experimental infection.

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    Natalia Anahí Juiz

    2017-03-01

    Full Text Available Congenital infection of Trypanosoma cruzi allows transmission of this parasite through generations. Despite the problematic that this entails, little is known about the placenta environment genetic response produced against infection. We performed functional genomics by microarray analysis in C57Bl/6J mice comparing placentas from uninfected animals and from animals infected with two different T. cruzi strains: K98, a clone of the non-lethal myotropic CA-I strain (TcI, and VD (TcVI, isolated from a human case of congenital infection. Analysis of networks by GeneMANIA of differentially expressed genes showed that "Secretory Granule" was a pathway down-regulated in both infected groups, whereas "Innate Immune Response" and "Response to Interferon-gamma" were pathways up-regulated in VD infection but not in K98. Applying another approach, the GSEA algorithm that detects small changes in predetermined gene sets, we found that metabolic processes, transcription and macromolecular transport were down-regulated in infected placentas environment and some pathways related to cascade signaling had opposite regulation: over-represented in VD and down-regulated in K98 group. We also have found a stronger tropism to the placental organ by VD strain, by detection of parasite DNA and RNA, suggesting living parasites. Our study is the first one to describe in a murine model the genetic response of placental environment to T. cruzi infection and suggests the development of a strong immune response, parasite genotype-dependent, to the detriment of cellular metabolism, which may contribute to control infection preventing the risk of congenital transmission.

  14. Eimeria stiedae: experimental infection in rabbits and the effect of treatment with toltrazuril and ivermectin.

    Science.gov (United States)

    Cam, Yücel; Atasever, Ayhan; Eraslan, Gökhan; Kibar, Murat; Atalay, Oznur; Beyaz, Latife; Inci, Abdullah; Liman, Bilal Cem

    2008-05-01

    The aim of this study was to investigate the clinical, haematological, biochemical, lipid peroxidation, ultrasonographic and pathologic findings in hepatic coccidiosis induced by Eimeria stiedae in rabbits, and also to compare the treatment effects of both toltrazuril and ivermectin separately and in combination. In this study, 56 rabbits were divided into eight groups. The first group was designated as healthy control group. Rabbits were infected with 40.000 sporulated oocysts of E. stiedae. Groups 2, 3, 4, 5, 6, 7 and 8 were allocated as the infected control group, infected+toltrazuril-treated group, infected+ivermectin-treated group, infected+toltrazuril+ivermectin-treated group, non-infected+toltrazuril-treated group, non-infected+ivermectin-treated group, non-infected+toltrazuril+ivermectin-treated group, respectively. Haematocrit, Haemoglobin and MCV values as well as percentage of lymphocyte decreased in Groups 2 and 4 whereas leucocyte counts and percentage of granulocyte leucocyte increased. Serum GGT, ALT and AST activities increased but albumin value decreased. Plasma MDA concentrations increased whereas erythrocyte CAT, GSH-Px, and SOD activities decreased. Mean oocyst numbers in per gram faeces (epg values) increased in both groups during the study. Ultrasonographic examination revealed that the liver was enlarged and had hyperechogenic parenchyma. Bile ducts were dilated and hyperechogenic and the gall bladder was dilated. The livers of these animals were enlarged and typical macroscopic and microscopic findings of coccidiosis were present. Treatment with toltrazuril and toltrazuril+ivermectin combination were highly effective in reducing faecal oocyst output in infected rabbits. Haematological, biochemical and lipid peroxidation parameters and, ultrasonographic findings of the liver were close to control values for Groups 3 and 5. Necropsy of these animals showed no visible lesions related to hepatic coccidiosis although a few oocysts were detected

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

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    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.

  16. Common carp have two subclasses of bonyfish specific antibody IgZ showing differential expression in response to infection

    NARCIS (Netherlands)

    Ryo, S.; Wijdeven, R.H.M.; Tyagi, A.; Hermsen, G.J.; Kono, T.; Karunasagar, I.; Rombout, J.H.W.M.; Sakai, H.; Verburg-van Kemenade, B.M.L.; Savan, R.

    2010-01-01

    Immunoglobulin heavy chains identified in bony fish are broadly classified into three classes namely IgM, IgD and IgZ. The most recently described isotype is IgZ, a teleosts-fish specific isotype that shows variations in gene structure across teleosts. In this study we have identified two IgZ

  17. Molecular evolution of GB virus B hepatitis virus during acute resolving and persistent infections in experimentally infected tamarins

    DEFF Research Database (Denmark)

    Takikawa, Shingo; Engle, Ronald E; Faulk, Kristina N

    2010-01-01

    GB virus B (GBV-B) causes acute hepatitis in experimentally infected tamarins. We compared evolutionary features in acute resolving and persistent GBV-B infection. We detected no evidence of evolution in four animals with clearance during weeks 9-12, whereas three animals with clearance during......(-3) substitutions per site year(-1) during weeks 1-52 and 53-104, respectively. Thus, there was a significant decrease in evolution over time, as found for hepatitis C virus. The rate of non-synonymous substitution per non-synonymous site compared with that of synonymous substitution per synonymous site decreased...... weeks 13-26 had several substitutions in their polyprotein sequence. A single tamarin had long-term GBV-B viraemia; analysis of virus recovered at weeks 2, 5, 12, 20, 26, 52 and 104 demonstrated that mutations accumulated over time. Overall, the amino acid substitution rate was 3.5x10(-3) and 1.1x10...

  18. Experimental Ascaris suum infection in the pig: worm population kinetics following single inoculations with three doses of infective eggs.

    Science.gov (United States)

    Roepstorff, A; Eriksen, L; Slotved, H C; Nansen, P

    1997-10-01

    To study population kinetics during primary Ascaris suum infections, 3 groups of 52 pigs each were inoculated with 100, 1000, or 10,000 infective eggs. In all groups, the majority of larvae was found in the liver on day 3 post inoculation (p.i.) and in the lungs on day 7 p.i. Liver white spots, caused by migrating larvae, were most numerous at day 7 p.i., whereafter they gradually healed, and only low numbers of granulation-tissue type white spots and lymphonodular white spots persisted at days 21-56 p.i. Independent of dose level, 47-58% of the inoculated eggs were recovered as larvae in the small intestine on day 10 p.i., but most larvae were eliminated at days 17-21 p.i. This elimination started earlier and removed a higher percentage of the worms with increasing inoculation dose, resulting in small strongly aggregated worm populations by day 28 p.i. (k of the negative binomial distribution was low: 0.2-0.4) without significant differences between groups. Thus, overdispersion, which is a characteristic of both porcine and human ascarosis, is found here under experimental conditions where aggregation factors like host behaviour, transmission rate, host status etc have been partly or totally controlled.

  19. Duration of equine influenza virus shedding and infectivity in immunised horses after experimental infection with EIV A/eq2/Richmond/1/07.

    Science.gov (United States)

    Paillot, R; Prowse, L; Montesso, F; Stewart, B; Jordon, L; Newton, J R; Gilkerson, J R

    2013-09-27

    Equine influenza (EI) is a major respiratory disease of horses. Recent outbreaks of EI have demonstrated the ease with which EI virus (EIV) can be transmitted internationally. This study aimed to improve our understanding of EIV shedding after infection of vaccinated horses, which would inform possible changes to current quarantine requirements. Our objectives were to compare commonly used diagnostic tests and to evaluate the relative merits of nasal and nasopharyngeal swabs for detection of EIV in vaccinated and unvaccinated ponies following EIV infection and to use these data to inform optimal quarantine procedures for the safe international movement of horses. Five ponies vaccinated against EI were infected experimentally with A/eq/Richmond/1/07 (Florida clade 2), 11 weeks after V2. Nasal and nasopharyngeal swabs were taken daily for 14 days and every 2 days for another 2 weeks. The 5 vaccinates were introduced sequentially for 48h to 3 groups of 2 naïve sentinel ponies each on days 2, 4 and 6 post-challenge respectively. Clinical signs of disease and EIV shedding were monitored for 14 days after co-mingling. EIV was detected by 3 different methods of detection (EIV nucleoprotein ELISA, EIV nucleoprotein qRT-PCR and isolation/titration in embryonated hens' eggs). Directigen™ EZ Flu A+B tests were also performed on samples from the vaccinated ponies for 6 days after infection. Results show that nasopharyngeal swabs were superior to nasal swabs, with increased frequency and amount of virus detected. The average mean duration of shedding was 6-8 days in naïve animals. All 3 sentinel groups were infected successfully with EIV after commingling with vaccinates, indicating up to 6 days of transmission. EI protection induced by vaccination is a dynamic process, naturally fluctuating and dependent on the time since last immunisation, with periods of high immunity (peak of immunity shortly after boost immunisation) and periods of susceptibility to EIV infection. This

  20. Chemometric analysis of biofluids from mice experimentally infected with Schistosoma mansoni

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    Keiser Jennifer

    2011-09-01

    Full Text Available Abstract Background The urinary metabolic fingerprint of a patent Schistosoma mansoni infection in the mouse has been characterized using spectroscopic methods. However, the temporal dynamics of metabolic alterations have not been studied at the systems level. Here, we investigated the systems metabolic changes in the mouse upon S. mansoni infection by modeling the sequence of metabolic events in urine, plasma and faecal water. Methods Ten female NMRI mice, aged 5 weeks, were infected with 80 S. mansoni cercariae each. Ten age- and sex-matched mice remained uninfected and served as a control group. Urine, plasma and faecal samples were collected 1 day before, and on eight time points until day 73 post-infection. Biofluid samples were subjected to 1H nuclear magnetic resonance (NMR spectroscopy and multivariate statistical analyses. Results Differences between S. mansoni-infected and uninfected control mice were found from day 41 onwards. One of the key metabolic signatures in urine and faecal extracts was an alteration in several gut bacteria-related metabolites, whereas the plasma reflected S. mansoni infection by changes in metabolites related to energy homeostasis, such as relatively higher levels of lipids and decreased levels of glucose. We identified 12 urinary biomarkers of S. mansoni infection, among which hippurate, phenylacetylglycine (PAG and 2-oxoadipate were particularly robust with regard to disease progression. Thirteen plasma metabolites were found to differentiate infected from control mice, with the lipid components, D-3-hydroxybutyrate and glycerophosphorylcholine showing greatest consistency. Faecal extracts were highly variable in chemical composition and therefore only five metabolites were found discriminatory of infected mice, of which 5-aminovalerate was the most stable and showed a positive correlation with urinary PAG. Conclusions The composite metabolic signature of S. mansoni in the mouse derived from perturbations

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

    Directory of Open Access Journals (Sweden)

    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.

  2. Molecular typing of Salmonella from Sergipe, Northeastern Brazil, showing the epidemiological relationship between poultry and human infection.

    Science.gov (United States)

    Góis, P B P; Carneiro, M R P; Jain, S; Santos, M I S; Batista, M V A; Cândido, A L

    2015-09-25

    Randomly amplified polymorphic DNA (RAPD) has been widely used for epidemiological and phylogenetic purposes ow-ing to its rapidity and efficiency. The aim of this study was to perform genome typing of Salmonella samples isolated from different sources by RAPD profiling. Thirty-three Salmonella samples from the bacterial collection of the Laboratório de Virologia Comparada, Departamento de Morfologia, Universidade Federal de Sergipe, Brazil, and two standard samples were used. RAPD profiling was conducted using six primers of the Ready-To-Go RAPD system. The amplified products were electro-phoresed on 5% polyacrylamide gel and silver-stained. RAPD analysis resulted in reproducible and stable banding patterns and showed high genetic diversity among the isolated strains. The Primer P1-generated dendrogram showed an epidemiologic relationship between the human and poultry isolated samples, highlighting the usefulness of RAPD for molecular typing and epidemiological studies.

  3. 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.

  4. Pathophysiological variability of different genotypes of human Blastocystis hominis Egyptian isolates in experimentally infected rats.

    Science.gov (United States)

    Hussein, Eman M; Hussein, Abdalla M; Eida, Mohamed M; Atwa, Maha M

    2008-04-01

    The genotyping of Blastocystis hominis clinical isolates obtained from 28 gastrointestinal symptomatic patients and 16 asymptomatic individuals were identified by polymerase chain reaction using sequenced-tagged site (STS) primers. Then, pathophysiological variability between different B. hominis genotypes was evaluated in experimentally infected rats. Only four B. hominis subtypes (1, 2, 3, and 4) were detected (18.2%, 9.1%, 54.5%, and 18.2%, respectively) in human isolates. In symptomatic isolates, subtypes 1, 3, and 4 were detected in 8 (28.6%), 16 (57.1%), and 4 (14.3%) patients, respectively. In asymptomatic isolates, subtypes 2, 3, and 4 were identified in 4 (25%), 8 (50%), and 4 (25%), respectively. Subtype 3 was the commonest in humans. Different degrees of pathological changes were found among infected rats by symptomatic subtypes compared with asymptomatic subtypes. The moderate and severe degrees of pathological changes were found only in symptomatic subtypes infected rats while mild degree was found only in asymptomatic subtypes infected rats. Only subtype 1 induced mortality rate with 25% among infected rats. On evaluation of the intestinal cell permeability in the Ussing chamber, a prominent increase in short circuit current (DeltaIsc) was found in symptomatic subtype 1 compared to symptomatic subtypes 3 and 4 infected rats. Minimal effects were found in the asymptomatic and control groups. The results proved that subtype 1 was clinically and statistically highly relevant to the pathogenicity of B. hominis while subtype 2 was irrelevant. Also, the results suggest the presence of pathogenic and nonpathogenic strains among subtypes 3 and 4.

  5. Highly diluted medication reduces parasitemia and improves experimental infection evolution by Trypanosoma cruzi

    Directory of Open Access Journals (Sweden)

    Aleixo Denise

    2012-07-01

    Full Text Available Abstract Background There is no published information about the use of different protocols to administer a highly diluted medication. Evaluate the effect of different protocols for treatment with biotherapic T. cruzi 17 dH (BIOTTc17dH on clinical/parasitological evolution of mice infected with T. cruzi-Y strain. Methods A blind, randomized controlled trial was performed twice, using 60 28-day-old male Swiss mice infected with T. cruzi-Y strain, in five treatment groups: CI - treated with a 7% ethanol-water solution, diluted in water (10 μL/mL ad libitum; BIOTPI - treated with BIOTTc17dH in water (10 μL/mL ad libitum during a period that started on the day of infection; BIOT4DI - treated with BIOTTc17dH in water (10 μL/mL ad libitum beginning on the 4th day of infection; BIOT4-5–6 - treated with BIOTTc17dH by gavage (0.2 mL/ animal/day on the 4th, 5th and 6th days after infection; BIOT7-8–9 - treated with BIOTTc17dH by gavage (0.2 mL/ animal/day on the 7th, 8th and 9th days after infection. We evaluated: parasitemia; total parasitemia (Ptotal; maximum peak of parasites; prepatent period (PPP - time from infection to detection of the parasite in blood; patent period (PP - period when the parasitemia can be detected in blood; clinical aspects; and mortality. Results Parasitological parameters in the BIOTPI and mainly in the BIOT4PI group showed better evolution of the infection compared to the control group (CI, with lower Ptotal, lower maximum peak of parasites, higher PPP, lower PP and longer survival times. These animals showed stable body temperature and higher weight gain and water consumption, with more animals having normal-appearing fur for longer periods. In contrast, groups BIOT4-5–6 and BIOT7-8–9 showed worse evolution of the infection compared to the control group, considering both parasitological and clinical parameters. The correlation analysis combined with the other data from this study indicated that the prepatent

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

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    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. Different Infective Forms Trigger Distinct Immune Response in Experimental Chagas Disease

    Science.gov (United States)

    Vieira, Paula Melo de Abreu; Francisco, Amanda Fortes; Machado, Evandro Marques de Meneses; Nogueira, Nívia Carolina; Fonseca, Kátia da Silva; Reis, Alexandre Barbosa; Teixeira-Carvalho, Andrea; Martins-Filho, Olindo Assis; Tafuri, Washington Luiz; Carneiro, Cláudia Martins

    2012-01-01

    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. PMID:22412949

  8. Response of Cytokines and Hydrogen Peroxide to Sporothrix schenckii Exoantigen in Systemic Experimental Infection.

    Science.gov (United States)

    Maia, Danielle Cardoso Geraldo; Gonçalves, Amanda Costa; Ferreira, Lucas Souza; Manente, Francine Alessandra; Portuondo, Deivys Leandro; Vellosa, José Carlos Rebuglio; Polesi, Marisa Campos; Batista-Duharte, Alexander; Carlos, Iracilda Zeppone

    2016-04-01

    The response of hydrogen peroxide (H2O2) and cytokines during an experimental sporotrichosis in male Swiss mice was assessed over a period of 10 weeks by monitoring macrophage activation challenged with exoantigen (ExoAg) from the fungus Sporothrix schenckii. The studied endpoints were: H2O2 production, fungal burden at spleen, apoptosis in peritoneal macrophages, and IL-1β, IL-6, IL-2, IL-10 production. During the two first weeks of infection was observed low burden of yeast in spleen and high response of H2O2, IL-2, and IL-1β. The weeks of highest fungal burden (fourth-sixth) coincided with major apoptosis in peritoneal macrophages, normal production of IL-6 and lower production of H2O2, IL-2, and IL-1β, suggesting a role for these three last in the early control of infection. On the other hand, IL-1β (but not IL-6) was recovered since the sixth week, suggesting a possible role in the late phase of infection, contributing to the fungal clearance in conjunction with the specific mechanisms. The IL-10 was elevated until the sixth, principally in the second week. These results evidences that ExoAg is involved in the host immune modulation, influencing the S. Schenckii virulence, and its role is related with the time of the infection in the model used.

  9. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  11. Experimental Leishmania major infection suppresses HIV-1 DNA vaccine induced cellular immune response.

    Science.gov (United States)

    Robinson, Tara M; Nelson, Robin; Artis, David; Scott, Phillip; Boyer, Jean D

    2004-01-01

    The AIDS epidemic in the developing world represents a major global crisis and an effective vaccine is imperative. However, many parasites are common in developing countries and can result in a state of chronic immune activation that is polarized towards a Th2 profile and which can potentially impair responses to vaccines or other infectious challenges. In this study we demonstrate that experimental Leishmania major infection of BALB/c mice inhibits responses to a DNA-based HIV-1 gag vaccine. L. major infection in BALB/c results in a polarized Th2 immune response. In this study naïve BALB/c mice immunized with the HIV-1 gag DNA vaccine mounted a cellular immune response against the vaccine antigen, HIV-1 gag. CD8+ T lymphocytes were able to respond in vitro to HIV-1 gag stimulation and secrete interferon (IFN)-gamma. However, L. major-infected, vaccinated BALB/c mice had a significantly reduced number of IFN-gamma-producing CD8+ T cells following in vitro stimulation with gag antigen. These data suggest that parasitic infection, which results in a Th2 profile, reduces the efficacy of DNA vaccines that are designed to induce antiviral CD8+ T cell responses. Copyright 2004 S. Karger AG, Basel

  12. Allergy skin test responses during experimental infection with respiratory syncytial virus.

    Science.gov (United States)

    Skoner, David P; Gentile, Deborah A; Angelini, Betty; Doyle, William J

    2006-06-01

    Allergy skin testing is one of the most frequently performed physician office procedures. Many factors can affect the results of those tests, including the well-defined suppressive effect of systemic antihistamines. False-positive allergen skin test results are known to occur; however, contributing factors are not well understood. To determine whether a viral upper respiratory tract infection affects allergy skin test responsiveness. We performed skin tests with histamine and a panel of geographically relevant inhalant allergens on 16 adults before and 3, 6, and 21 days after experimental exposure to respiratory syncytial virus (RSV), a virus that causes signs and symptoms of a cold. The RSV exposure, with and without documented infection, caused increased wheal and flare areas to histamine and allergen and de novo positive allergen test responses in individuals with no measurable responses at baseline. These were noted as late as 21 days after RSV exposure and may be consistent with mediation by up-regulated neurogenic inflammation during RSV infection. These results may have implications for explaining the cause of such well-known complications of RSV infection as otitis media, bronchiolitis, and asthmatic exacerbation.

  13. The Effect of Marshallagia marshalli on Serum Gastrin Concentrations in Experimentally Infected Lambs.

    Science.gov (United States)

    Moradpour, Nona; Borji, Hassan; Razmi, Gholamreza; Maleki, Mohsen; Kazemi, Hossein

    2016-08-01

    :  Because there appeared to be no data available on serum gastrin concentrations in animals infected with Marshallagia marshalli, and considering the high prevalence of this parasite in livestock throughout many countries, we decided to perform research in the field using experimental infection. After surgical implantation of abomasal cannula into 10 male Baluchi sheep, each animal was orally infected with 5,000 M. marshalli larvae. Serum gastrin concentrations and abomasal pH were measured with a human ELISA kit and a PHM LE438 standard pH electrode, respectively. According to the results obtained from the study, serum gastrin increased after 14 and 21 days post-infection (dpi), while abomasal pH increased after 7 dpi and reached a maximal value 16 dpi. The increase in serum gastrin concentration was revealed 6 days after elevation in abomasal pH, which could be the result of reduced acid secretion. Generally, the present study pointed out that a limited number of M. marshalli could increase serum gastrin concentrations.

  14. Implications for a regulated replication of Borna disease virus in brains of experimentally infected Lewis rats.

    Science.gov (United States)

    Porombka, Doris; Baumgärtner, Wolfgang; Eickmann, Markus; Herden, Christiane

    2008-04-01

    The neurotropic Borna disease virus (BDV) causes typically a persistent virus infection of the central nervous system. In order to investigate whether an adapted virus replication contributes to BDV persistence in vivo, a fast and reliable real-time RT-PCR assay was constructed to quantify the amounts of leader-containing (leBDV) as a marker for virus replication, genomic (vBDV) and nucleoprotein-(BDV-N +ssRNA)-specific RNA. Therefore, leBDV, vBDV and BDV-N +ssRNA values were determined in experimentally infected Lewis rats between 14 and 90 days post infection (dpi). Surprisingly low leBDV values were found compared to vBDV and the abundantly expressed BDV-N transcripts. vBDV multiplied only in the acute phase of infection followed by constant expression until 90 dpi. Ratios of vBDV to leBDV were 401:1 at 14 dpi and diminished to 209:1 at 90 dpi, indicating a regulated co-expression of replicative intermediates as a potential prerequisite for viral persistence.

  15. Susceptibility to Yersinia pestis experimental infection in wild Rattus rattus, reservoir of plague in Madagascar.

    Science.gov (United States)

    Tollenaere, C; Rahalison, L; Ranjalahy, M; Duplantier, J-M; Rahelinirina, S; Telfer, S; Brouat, C

    2010-06-01

    In Madagascar, the black rat, Rattus rattus, is the main reservoir of plague (Yersinia pestis infection), a disease still responsible for hundreds of cases each year in this country. This study used experimental plague challenge to assess susceptibility in wild-caught rats to better understand how R. rattus can act as a plague reservoir. An important difference in plague resistance between rat populations from the plague focus (central highlands) and those from the plague-free zone (low altitude area) was confirmed to be a widespread phenomenon. In rats from the plague focus, we observed that sex influenced plague susceptibility, with males slightly more resistant than females. Other individual factors investigated (weight and habitat of sampling) did not affect plague resistance. When infected at high bacterial dose (more than 10⁵ bacteria injected), rats from the plague focus died mainly within 3-5 days and produced specific antibodies, whereas after low-dose infection (plague resistance level and the course of infection in the black rat would contribute to a better understanding of plague circulation in Madagascar.

  16. Efficacy of clorsulon for the treatment of experimentally induced infections of Fasciola hepatica in goats.

    Science.gov (United States)

    Sundlof, S F; Bliss, E L; Greiner, E C; Tran, T Q; Wertenberger, M A

    1991-01-01

    A dose titration study was undertaken to determine the efficacy of clorsulon against the adult stage of Fasciola hepatica in goats. Thirty-nine goats were experimentally infected with metacercariae of F hepatica. At 14 weeks after infection, each goat was assigned randomly to 1 of 5 groups. Goats in groups 1 to 4 received a single oral administration of clorsulon at dosages of 3.5, 7, 11, and 15 mg/kg of body weight, respectively. The fifth group of goats (control group) was infected with F hepatica, but were not treated with clorsulon. Postmortem examination of goats at 3 weeks after treatment revealed mean reductions in numbers of flukes of 83, 98, 99, and 100% for groups 1 to 4, respectively. Mean percentage of reduction in eggs following treatment of groups was 82, 98, 100, and 100%, respectively. The clinical effects of clorsulon in 24 goats that were not infected with F hepatica were studied. Goats in groups 1 to 3 received a single oral administration of clorsulon at dosages of 7, 21, and 35 mg/kg, respectively, every other day for a total of 3 doses/goat. Group-4 goats (control group) received a vehicle placebo. Goats in group 3 were subject to postmortem examination at 14 days after dosing. Abnormal signs or lesions that could be attributed to clorsulon were not found in any goat.

  17. 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

  18. Experimental mixed infection with Yersinia enterocolitica and Listeria monocytogenes in guinea pigs.

    Science.gov (United States)

    Najdenski, H; Nikolova, S; Wesselinova, D; Kazatchca, D; Vesselinova, A

    1998-12-01

    The pathogenesis and the cell immune response (CIR) of guinea pigs after mixed infection with Y. enterocolitica and L. monocytogenes was investigated. The guinea pigs were infected per os with 1.1 x 10(9) CFU Y. enterocolitica 0:3, (pYV+) and four days later with 1.1 x 10(9) CFU L. monocytogenes 4B. Clinical, paraclinical and morphological findings attending the infectious process were followed in dynamics up to the 28th day post infection (p.i.) with L. monocytogenes. The phagocyting activity of alveolar macrophages (aMa) was suppressed against Y. enterocolitica, in contrast to peritoneal macrophages (pMa) engulfing yersiniae more actively at the end of the study. Moreover, the tendency of augmented entering in both phagocytes of L. monocytogenes cells was well demonstrated, starting at the earlier intervals of examination. Histopathological studies showed a purulent meningoencephalitis and a catarrhal pneumonie, non-reactive micronecroses in the spleen and lymphadenitis catarrhalis in the mesenteric lymph nodes. Analysis of the T-cell immune response (T-CIR) showed maximal values in the spleen lymphocytes after Y. enterocolitica and L. monocytogenes mixed infection. The B-CIR occurred early (at the 7th day p.i.) and was maximal at the 28th day p.i. in blood lymphocytes. The results obtained demonstrated that the mixed infection of guinea pigs with Y. enterocolitica and L. monocytogenes runs has a non lethal, generalized illness with a dominant role of L. monocytogenes cells.

  19. Role of IL-1β in experimental cystic fibrosis upon P. aeruginosa infection.

    Directory of Open Access Journals (Sweden)

    Jennifer Palomo

    Full Text Available Cystic fibrosis is associated with increased inflammatory responses to pathogen challenge. Here we revisited the role of IL-1β in lung pathology using the experimental F508del-CFTR murine model on C57BL/6 genetic background (Cftr(tm1eur or d/d, on double deficient for d/d and type 1 interleukin-1 receptor (d/d X IL-1R1-/-, and antibody neutralization. At steady state, young adult d/d mice did not show any signs of spontaneous lung inflammation. However, IL-1R1 deficiency conferred partial protection to repeated P. aeruginosa endotoxins/LPS lung instillation in d/d mice, as 50% of d/d mice succumbed to inflammation, whereas all d/d x IL-1R1-/- double mutants survived with lower initial weight loss and less pulmonary collagen and mucus production, suggesting that the absence of IL-1R1 signaling is protective in d/d mice in LPS-induced lung damage. Using P. aeruginosa acute lung infection we found heightened neutrophil recruitment in d/d mice with higher epithelial damage, increased bacterial load in BALF, and augmented IL-1β and TNF-α in parenchyma as compared to WT mice. Thus, F508del-CFTR mice show enhanced IL-1β signaling in response to P. aeruginosa. IL-1β antibody neutralization had no effect on lung homeostasis in either d/d or WT mice, however P. aeruginosa induced lung inflammation and bacterial load were diminished by IL-1β antibody neutralization. In conclusion, enhanced susceptibility to P. aeruginosa in d/d mice correlates with an excessive inflammation and with increased IL-1β production and reduced bacterial clearance. Further, we show that neutralization of IL-1β in d/d mice through the double mutation d/d x IL-1R1-/- and in WT via antibody neutralization attenuates inflammation. This supports the notion that intervention in the IL-1R1/IL-1β pathway may be detrimental in CF patients.

  20. Comparison of Abortion and Infection after Experimental Challenge of Pregnant Bison and Cattle with Brucella abortus Strain 2308▿

    Science.gov (United States)

    Olsen, S. C.; Johnson, C.

    2011-01-01

    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 during midgestation. The incidence of abortion, fetal infection, uterine or mammary infection, or infection in maternal tissues after experimental challenge was greater (P abort, the time between experimental challenge and abortion was shorter (P abortion did not differ (P > 0.05) between cattle and bison. The results of our study suggest that naive bison and cattle have similarities and differences after experimental exposure to a virulent B. abortus strain. Although our data suggest that bison may be more susceptible to infection with Brucella, some pathogenic characteristics of brucellosis were similar between bison and cattle. PMID:21976222

  1. INVOLVEMENT OF BACTERICIDAL FACTORS FROM THROMBIN-STIMULATED PLATELETS IN CLEARANCE OF ADHERENT VIRIDANS STREPTOCOCCI IN EXPERIMENTAL INFECTIVE ENDOCARDITIS

    NARCIS (Netherlands)

    VANDERWERFF, J; ZAAT, SAJ; JOLDERSMA, W; HESS, J

    Platelets activated with thrombin release bactericidal factors. We studied the role of the susceptibility of viridans streptococci to these bactericidal factors in the development of infective endocarditis (IE). By using the experimental endocarditis rabbit model, the initial adherence and the

  2. Effect of diminazene aceturate, levamisole and vitamin C combination therapy in rats experimentally infected with Trypanosoma brucei brucei.

    Science.gov (United States)

    Chekwube, Adieme Ijeoma; Onyema, Ezeh Ikenna; Ikenna, Ugochukwu Emmanuel; Ezeokonkwo, Romanus Chukwuduruo

    2014-06-01

    To investigate the effect of diminazene aceturate (DA) alone or in combination with either levamisole and/or Vitamin C in albino rats experimentally infected with Trypanosoma brucei brucei. Thirty adult male albino rats, randomly assigned into 6 groups (A-F) of 5 rats each were used. They were either infected with 1×10(6) trypanosomes intraperitoneally (groups A-E) or uninfected (group F). The different groups were treated respectively as follows: group A-with 3.5 mg/kg DA; group B-3.5 mg/kg DA and 7.5 mg/kg levamisole; group C-3.5 mg/kg DA and 100 mg/kg vitamin C; and group D-3.5 mg/kg DA and 7.5 mg/kg levamisole and 100 mg/kg vitamin C. Group E was left untreated. Parameters assessed include: rectal temperature, body weight changes, packed cell volume (PCV), Haemoglobin concentration (Hb), total leucocyte count (TLC) differential leucocyte count (DLC), parasitaemia, clinical signs and survivability. Average pre-patent period of 5 days was recorded. Parasites in the blood were cleared in all treated groups (A-D) within 48 hours post treatment (PT). Untreated rats in group E died between 25 and 32 days post infection (PI). Relapse was not recorded in all the treated groups (A-D). The initial reduction in PCV, Hb, TLC and increases in rectal temperature following infection were reversed by the treatments. The rats that received drug combinations (groups B, C and D) showed faster and higher recovery rates than the uninfected control and group A. Levamisole and/or Vitamin C combination with DA were more effective in the treatment of rats infected with Trypanosoma brucei brucei. Copyright © 2014 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

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

    2014-08-19

    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 and viral tissue distribution. We inoculated sixteen black-headed gulls with 1 × 10(4) median tissue culture infectious dose HPAIV H5N1 (A/turkey/Turkey/1/2005) intratracheally and intraesophageally. Birds were monitored daily until 12 days post inoculation (dpi). Oropharyngeal and cloacal swabs were collected daily to detect viral shedding. Necropsies from birds were performed at 2, 4, 5, 6, 7, and 12 dpi. Sampling from selected tissues was done for histopathology, immunohistochemical detection of viral antigen, PCR, and viral isolation. Our study shows that all inoculated birds were productively infected, developed systemic disease, and had a high morbidity and mortality rate. Virus was detected mainly in the respiratory tract on the first days after inoculation, and then concentrated more in pancreas and central nervous system from 4 dpi onwards. Birds shed infectious virus until 7 dpi from the pharynx and 6 dpi from the cloaca. We conclude that black-headed gulls are highly susceptible to disease with a high mortality rate and are thus more likely to act as sentinel species for the presence of the virus than as long-distance carriers of the virus to new geographical areas.

  4. Comparative efficacy of tulathromycin and tildipirosin for the treatment of experimental Mycoplasma bovis infection in calves

    OpenAIRE

    Bartram, David J.; Moyaert, Hilde; Vanimisetti, Bindu H.; Ramage, Clifford P.; Reddick, David; Stegemann, Michael R

    2016-01-01

    Abstract The objective of this negative controlled, blinded, randomised, parallel group study was to compare the efficacy of two injectable macrolide antimicrobials, tulathromycin and tildipirosin, administered by single subcutaneous injection at dose rates of 2.5 and 4.0 mg kg−1 bodyweight, respectively, in the treatment of an experimentally induced Mycoplasma bovis infection in calves. A total of 238 M. bovis‐negative calves were challenged on three consecutive days with M. bovis by endobro...

  5. The pathology of experimental Schistosoma curassoni infections in mice and hamsters.

    Science.gov (United States)

    Vercruysse, J; Fransen, J; Southgate, V R; Rollinson, D

    1986-11-01

    The histopathology of experimental Schistosoma curassoni infections in white mice and hamsters was studied. In mice, hepatic lesions were severe with characteristic extensive perilobular fibrosis and large perilobular granulomas throughout the parenchyma. Only a few granulomas were detected in the lung, small intestine, and rectum of mice. In hamsters, lesions in the liver were limited. Few granulomas were found but the giant cell reaction was pronounced. Lesions in the lung and small intestine were minimal. Many subserosal and submucosal epithelioid cell granulomas were in the colon and rectum of hamsters. Parasites were not detected in the bladder of either mice or hamsters.

  6. Cellular and molecular immune responses of the sea bass (Dicentrarchus labrax) experimentally infected with betanodavirus

    DEFF Research Database (Denmark)

    Scapigliati, G.; Buonocore, F.; Randelli, E.

    2010-01-01

    Naïve sea bass juveniles (38.4 ± 4.5 g) were intramuscularly infected with a sublethal dose of betanodavirus isolate 378/I03, followed after 43 days by a similar boosting. This infection resulted in an overall mortality of 7.6%. At various intervals, sampling of fish tissues was performed to inve...... was also observed, while the other tested genes did not show any significant variations with respect to mock-treated fish. Overall, our work represents a first comprehensive analysis of cellular and molecular immune parameters in a fish species exposed to a pathogenic virus....

  7. 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

  8. Establishment of macrocyclic lactone resistant Dirofilaria immitis isolates in experimentally infected laboratory dogs.

    Science.gov (United States)

    Pulaski, Cassan N; Malone, John B; Bourguinat, Catherine; Prichard, Roger; Geary, Timothy; Ward, Danielle; Klei, Thomas R; Guidry, Tal; Smith, George 'Bud'; Delcambre, Brooke; Bova, Jonathan; Pepping, Jenny; Carmichael, James; Schenker, Rudolf; Pariaut, Romain

    2014-11-07

    Strains of Dirofilaria immitis suspected of lack of efficacy (LOE) to macrocyclic lactone (ML) preventive drugs have been increasingly reported in dogs by practicing veterinarians since 2005 in the Lower Mississippi Delta region. If proven, and not controlled in the early stages, the emergence of ML drug resistance threatens to become a widespread problem in the US that may limit the effectiveness of current preventive drug treatment methods. To validate practice reports, a statewide survey of Louisiana veterinarians was done to define the extent of the problem and identify focal 'hotspots' of reported ML LOEs using Geographic Information Systems (GIS) methods. The present study then utilized microfilariae (Mf) from two canine field cases from different state locations that fit criteria for a high index of suspicion of LOE against heartworms by ML drugs. Blood containing Mf from the canine field cases was used to infect and produce L3 in Aedes aegypti for experimental infection of two groups of dogs, each of which contained two laboratory dogs, one treated with prophylactic ivermectin (12 μg/kg) monthly for 6 months at twice the label dose (6 μg/kg), and one untreated control. Both treated and untreated dogs from Group I and Group II developed patent D. immitis infections by 218 DPI and 189 DPI, respectively, as evidenced by a positive occult heartworm antigen test and microfilaremia by the Knott's test. Mf counts gradually increased post-patency in test and control dogs. Infective larvae raised from microfilariae from the treated Group I dog were used to successfully establish a second generation isolate, confirming heritability of resistance in the face of a monthly ivermectin challenge dose of 24 μg/kg, given monthly for 3 months. These experimental infection studies provide in vivo evidence of the existence of ML drug resistance in dogs infected by D. immitis L3 from suspect field LOE cases in the Lower Mississippi Delta. Results encourage further work on

  9. 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...

  10. Differences in intermittent and continuous fecal shedding patterns between natural and experimental Mycobacterium avium subspecies paratuberculosis infections in cattle

    Science.gov (United States)

    The objective of this paper is to study shedding patterns of cows infected with Mycobacterium avium subsp. paratuberculosis (MAP). While multiple single farm studies of MAP dynamics were reported, there is not large-scale meta-analysis of both natural and experimental infections. Large difference...

  11. 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

  12. Diagnosis of the strongyloid nematode Strongyloides venezuelensis in experimentally infected rats.

    Science.gov (United States)

    Marques, P D; Malta, F M; Meisel, D M C L; Corral, M A; Pinho, J R; Costa-Cruz, J M; Chieffi, P P; Gryschek, R C B; Paula, F M

    2016-07-01

    Strongyloides venezuelensis is an intestinal nematode of rats, frequently used as a model for studying human and animal strongyloidiasis. In the present study, we evaluated parasitological, serological and molecular methods for the diagnosis of experimental S. venezuelensis in rats, Rattus norvegicus. Blood and faecal samples were collected and analysed up to 60 days post infection (pi) with adult worm recovery occurring from 5 to 45 days pi. Using an enzyme-linked immunosorbent assay (ELISA), serum levels of IgG antibodies increased up to 28 days pi, thereafter decreasing by day 60 pi. Polymerase chain reaction (PCR) assays detected S. venezuelensis DNA in faecal samples of rats from 5 to 21 days pi. The present study therefore represents the first step towards improving the diagnosis of experimental strongyloidiasis.

  13. Experimental infection of Foxes with European bat Lyssaviruses type-1 and 2

    Directory of Open Access Journals (Sweden)

    Biarnais Mélanie

    2009-05-01

    Full Text Available Abstract Background Since 1954, there have been in excess of 800 cases of rabies as a result of European Bat Lyssaviruses types 1 and 2 (EBLV-1, EBLV-2 infection, mainly in Serotine and Myotis bats respectively. These viruses have rarely been reported to infect humans and terrestrial mammals, as the only exceptions are sheep in Denmark, a stone marten in Germany and a cat in France. The purpose of this study was to investigate the susceptibility of foxes to EBLVs using silver foxes (Vulpes vulpes as a model. Results Our experimental studies have shown that the susceptibility of foxes to EBLVs is low by the intramuscular (IM route, however, animals were sensitive to intracranial (IC inoculation. Mortality was 100% for both EBLV-1 (~4.5 logs and EBLV-2 (~3.0 logs delivered by the IC route. Virus dissemination and inflammatory infiltrate in the brain were demonstrated but virus specific neutralising antibody (VNA was limited (log(ED50 = 0.24–2.23 and 0.95–2.39 respectively for specific EBLV-1 and EBLV-2. Foxes were also susceptible, at a low level, to peripheral (IM infection (~3.0 logs with EBLV-1 but not EBLV-2. Three out of 21 (14.3% foxes developed clinical signs between 14 and 24 days post-EBLV-1 infection. None of the animals given EBLV-2 developed clinical disease. Conclusion These data suggest that the chance of a EBLV spill-over from bat to fox is low, but with a greater probability for EBLV-1 than for EBLV-2 and that foxes seem to be able to clear the virus before it reaches the brain and cause a lethal infection.

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

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    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.

  15. 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.

  16. Bactericidal Efficacy of Photodynamic Therapy and Chitosan in Root Canals Experimentally Infected with Enterococcus faecalis: An In Vitro Study.

    Science.gov (United States)

    Camacho-Alonso, Fabio; Julián-Belmonte, Encarnación; Chiva-García, Fernando; Martínez-Beneyto, Yolanda

    2017-04-01

    To evaluate the antibacterial efficacy of photodynamic therapy (PDT) and chitosan against Enterococcus faecalis and assess the possible enhancive effect of chitosan on the photosensitizer methylene blue in experimentally infected root canals of extracted human teeth in vitro. E. faecalis is frequently found in persistent endodontic infections. In this context, the antimicrobial PDT or newer antibacterial alternatives such as chitosan could become modern alternatives to existing antibacterial treatment approaches. One hundred two single-rooted extracted teeth were used. The teeth were contaminated with 0.1 mL E. faecalis (3 × 10(8) cell/mL). These were randomized into six treatment groups (n = 17 teeth): Group 1 (2.5% NaOCl); Group 2 (PDT); Group 3 (chitosan 3 mg/mL); Group 4 (PDT+chitosan 3 mg/mL); Group 5 (positive control, no treatment); and Group 6 (negative control, no inoculation, no treatment). The canal content was sampled with sterile paper points. The samples were cultured on blood agar plates to determine the number of colony-forming units (CFU)/mL. Five teeth in each group were analyzed by scanning electron microscope (SEM) to determine the percentage of area with contamination and debris. The positive control group showed the highest number of CFU/mL, with statistically significant differences in comparison with the other treatment groups (p ≤ 0.05). Group 4 (PDT+chitosan) showed the lowest CFU/mL count, followed by Group 2 (PDT alone), which obtained similar results to Group 1 (NaOCl), but there was no significance between the treated groups. SEM images showed that Group 4 (PDT+Chitosan) showed the lowest area of contamination. Combination of PDT and chitosan showed antibacterial potential against endodontic infection by E. faecalis.

  17. Foot-and-Mouth Disease in Red Deer - Experimental Infection and Test Methods Performance.

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    Kittelberger, R; Nfon, C; Swekla, K; Zhang, Z; Hole, K; Bittner, H; Salo, T; Goolia, M; Embury-Hyatt, C; Bueno, R; Hannah, M; Swainsbury, R; O'Sullivan, C; Spence, R; Clough, R; McFadden, A; Rawdon, T; Alexandersen, S

    2017-02-01

    The aim of this study was to evaluate a number of foot-and-mouth disease (FMD) test methods for use in red deer. Ten animals were intranasally inoculated with the FMD virus (FMDV) O UKG 11/2001, monitored for clinical signs, and samples taken regularly (blood, serum, oral swabs, nasal swabs, probang samples and lesion swabs, if present) over a 4-week period. Only one animal, deer 1103, developed clinical signs (lesions under the tongue and at the coronary band of the right hind hoof). It tested positive by 3D and IRES real-time reverse transcription polymerase chain reaction (rRT-PCR) in various swabs, lesion materials and serum. In a non-structural protein (NSP) in-house ELISA (NSP-ELISA-IH), one commercial ELISA (NSP-ELISA-PR) and a commercial antibody NSP pen side test, only deer 1103 showed positive results from day post-inoculation (dpi) 14 onwards. Two other NSP-ELISAs detected anti-NSP serum antibodies with lower sensitivity. It also showed rising antibody levels in the virus neutralization test (VNT), the in-house SPO-ELISA-IH and the commercial SPO-ELISA-PR at dpi 9, and in another two commercial SPO-ELISAs at dpi 12 (SPO-ELISA-IV) and dpi 19 (SPO-ELISA-IZ), respectively. Six of the red deer that had been rRT-PCR and antibody negative were re-inoculated intramuscularly with the same O-serotype FMDV at dpi 14. None of these animals became rRT-PCR or NSP-ELISA positive, but all six animals became positive in the VNT, the in-house SPO-ELISA-IH and the commercial SPO-ELISA-PR. Two other commercial SPO-ELISAs were less sensitive or failed to detect animals as positive. The rRT-PCRs and the four most sensitive commercial ELISAs that had been used for the experimentally inoculated deer were further evaluated for diagnostic specificity (DSP) using 950 serum samples and 200 nasal swabs from non-infected animals. DSPs were 100% for the rRT-PCRs and between 99.8 and 100% for the ELISAs. © 2015 The Authors. Transboundary and Emerging Diseases Published by Blackwell

  18. A FURTHER EXPERIMENTAL STUDY ON EXCITATION OF INFECTIONS OF THE THROAT.

    Science.gov (United States)

    Grant, S B; Mudd, S; Goldman, A

    1920-06-30

    Improvements are described in the method of following temperature changes, and thus alterations in vasomotor tone, in exposed mucous membranes. Invention of an applicator holder, by means of which more sure and stable apposition of the thermopile terminals to the mucous surface may be effected has been the chief advance. Minor improvements have been the use of a saliva ejector and of better calibration technique. The palatine tonsils, like the palate, pharynx, and skin, react to chilling of the body surface with reflex vasoconstriction and ischemia. On rewarming the subject the tonsils quickly more than recover their former blood supply, actually becoming hyperemic; the skin returns to about its control condition; the pharynx and palate remain somewhat ischemic. The hypothesis is advanced that one factor in the beneficial hardening effect of cold bathing and outdoor living, with its incident heightened immunity to respiratory infection, may be the training of the vasomotor system in the direction of development in the pharynx of a reaction of hyperemia following chilling, similar to that observed in the tonsils of the present subjects. With inhalation of amyl nitrite, the skin temperature has always shown a sharp transient rise. The mucous membrane, if relatively ischemic, responds by a rise corresponding to the skin flush. If already hyperemic, local vasodilation in the mucous membrane with amyl nitrite is more than counterbalanced by the lowering of the general blood pressure, and the temperature falls. The flora of the pharynx and tonsils, studied by the unsatisfactory method described, showed, in several instances, after experimentation changes apparently due to proliferation of one of the microorganisms already present. In one case Streptococcus haemolyticus, in one Micrococcus catarrhalis, and in a third Bacillus influenzae was the organism showing a relative increase in numbers. The first two instances were associated with sore throat, the third with slight

  19. Understanding Experimental LCMV Infection of Mice: The Role of Mathematical Models

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    Gennady Bocharov

    2015-01-01

    Full Text Available Virus infections represent complex biological systems governed by multiple-level regulatory processes of virus replication and host immune responses. Understanding of the infection means an ability to predict the systems behaviour under various conditions. Such predictions can only rely upon quantitative mathematical models. The model formulations should be tightly linked to a fundamental step called “coordinatization” (Hermann Weyl, that is, the definition of observables, parameters, and structures that enable the link with a biological phenotype. In this review, we analyse the mathematical modelling approaches to LCMV infection in mice that resulted in quantification of some fundamental parameters of the CTL-mediated virus control including the rates of T cell turnover, infected target cell elimination, and precursor frequencies. We show how the modelling approaches can be implemented to address diverse aspects of immune system functioning under normal conditions and in response to LCMV and, importantly, make quantitative predictions of the outcomes of immune system perturbations. This may highlight the notion that data-driven applications of meaningful mathematical models in infection biology remain a challenge.

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

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    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

  1. Antischistosomal activity of acridanone- hydrazones in Cebus monkeys experimentally infected with the SJ strain of Schistosoma mansoni

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    Paulo Marcos Zech Coelho

    1995-09-01

    Full Text Available In this study, four compounds were utilized at the dose of 12.5mg/kg body weight, p.o., to treat Cebus monkeys experimentally infected with about 200 cercariae of Schistosoma mansoni (SJ strain, via transcutaneous route. The oograms performed with rectal snips, as well as stool examinations carried out periodically, showed no viable eggs of the parasite, from day 29 to 226post-treatment. The perfusion undertaken after killing the animals showed absence of worms in the treated monkeys, whereas 83 worms were recovered from the control, thus corroborating the results obtained by means of oograms and coproscopy. These results confirm the efficacy of 9-acridanone- hydrazones previously tested against the LE strain of S. mansoni. The low curative dose and apparent absence of toxicity render these dmgs an important therapeutic reserve, taking into consideration the reports on the resistance of S. mansoni to the modern drugs oxamniquine and praziquantel.

  2. The dynamic influence of the DRB1*1101 allele on the resistance of sheep to experimental Teladorsagia circumcincta infection

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    Hassan Musa

    2011-03-01

    Full Text Available Abstract Suffolk sheep carrying the DRB1*1101 (previously referred to as-DRB1*0203 or G2 allele have been reported to show increased resistance to natural Teladorsagia circumcincta infection compared to non-carriers. The objective of this study was to compare the biochemical and physiological responses of DRB1*1101 carrier and non-carrier twin lambs to an experimental infection with 3 × 104 L3 Teladorsagia circumcincta. The variables studied included worm burden, faecal egg count, abomasal mast cells, IgA, IgE, IgG1 plus IgG2 and haematological parameters at 0, 3, 7, 21 and 35 days post infection (dpi, and duodenal smooth muscle contractility at 0 and 35 dpi. DRB1*1101 carrier lambs had significantly lower worm burden, higher mast cell and plasma platelet counts than the DRB1*1101 non-carriers (P DRB1*1101 non-carrier lambs had a significantly higher plasma lymphocyte count, and produced greater duodenal contractile force relative to the carrier lambs (P DRB1*1101 is acquired rather than innate, depends on worm expulsion rather than fecundity and is dependent on mucosal mast cell proliferation, platelet activation, and IgA and IgE antibody responses.

  3. Pharmacodynamic evaluation of a reference and a generic toltrazuril preparation in broilers experimentally infected with Eimeria tenella or E. acervulina.

    Science.gov (United States)

    Alcala-Canto, Y; Ramos-Martinez, E; Tapia-Perez, G; Gutierrez, L; Sumano, H

    2014-02-01

    Abstract 1. The aim of this study was to investigate the effects on pigmentation, faecal oocyst output, immune responsiveness and reactive oxygen species (ROS) generation following treatment with either the reference toltrazuril (Baycox) or a generic preparation (gen-TTZ), during an experimental Eimeria tenella (Et) or E. acervulina (Ea) infection of 210 Ross broiler chickens. 2. Results showed a significant difference on the anticoccidial efficacy 6 d after treating infected animals with Baycox (Et: 99.69% and Ea: 99.52%) or gen-TTZ (Et:85.71% and Ea 81.81%). 3. Gen-TTZ-treated animals were less strongly carotenoid-pigmented than Baycox-treated broilers. Mean plasma carotenoid concentrations were significantly higher in groups treated with Baycox than in broilers given gen-TTZ. 4. Treatment of animals with Baycox led to a significant decrease in ability of the peripheral blood mononuclear cells to produce ROS in contrast to gen-TTZ-treated groups. Baycox, but not generic toltrazuril, increased IL-10 and decreased tumour necrosis factor alpha (TNF-α) concentrations in chickens infected with E. tenella and E. acervulina. 5. It is suggested that differences in anticoccidial efficacy may be observed when using a generic toltrazuril product. Hence, in addition to plasma profiles of drugs, standardised clinical control tests may be necessary for generic formulations, particularly if other parameters are important to achieve a better control of coccidiosis.

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

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    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

  5. Evaluation of animal performance, feed intake, and economic losses in sheep experimentally infected with Trypanosoma vivax

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    Parmênedes Dias de Brito

    2017-06-01

    Full Text Available Trypanosoma vivax is a protozoan originating from the African continent, which, although it has not yet been able to complete its biological cycle in South America, due to the absence of the tsetse fly, can still cause death in ruminants. The objective of this study was to verify the effects of T. vivax on the measurements and indices in sheep that characterize animal performance, as well as on economic losses in meat animals. Twenty intact adult male sheep were used for this study, all of approximately the same ages and weights, reared in confinement, and subjected to the same management and diet, which was balanced and supplemented with adequate minerals. The animals were divided into two groups: the control group (CG and the infected group (IG, which was inoculated intravenously with 1.3 x 105 trypomastigotes of T. vivax. Feed intake was verified daily, whereas the feed conversion (FC, feed efficiency index (FEI, and weight gain were obtained weekly. Total weight gain (TWG was determined after 70 days post-infection. The economic loss was calculated by subtracting the value obtained (IG from the expected value (CG, and the difference was expressed as a percentage. A randomized block design was used to isolate the effect of the initial weight. The means were compared by the Student “t” test at 5%. Of the 10 infected animals, one died from the parasitism, yielding a rate much lower than that observed in natural outbreaks. The groups presented similar feed intakes throughout the experimental period; however, the TWG of the infected group was significantly lower (50.7% than that of the CG. Similarly, the daily weight gain (DWG, feed conversion (FC, and feed efficiency index (FEI of the IG were significantly lower than those of the CG. In addition, the worst rates of FC and FEI coincided with parasitemia peaks and recurrences, probably due to immunological demand and tissue repair. The abdominal circumference of the infected animals was

  6. 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

  7. Proteomic analysis of Ascaridia galli. Identification of immunoreactive proteins in naturally and experimentally infected hens.

    Science.gov (United States)

    González-Miguel, Javier; Marcos-Atxutegi, Cristina; de Castello, Roberta Bottari; Carpani, Sara; Morchón, Rodrigo; Simón, Fernando

    2013-09-23

    Ascaridia galli, intestinal parasite of domestic fowl, is responsible of economic losses in avian exploitations. However, molecular mechanisms that govern avian ascaridiasis remain largely unknown. The aim of the present work was to identify proteins of A. galli recognized by the immune system of naturally and experimentally infected hens, using two-dimensional electrophoresis (2-DE) and mass spectrometry (MS). Sixteen immunoreactive proteins of A. galli were identified. These proteins are mainly related to different metabolic processes, cell motility and binding activities. The timing evolution of this recognition pattern was studied using serum samples from experimentally infected hens, allowing us to observe an early recognition of many of these antigens. Many of them were isoforms from lipid and plasminogen-binding proteins. Moreover, plasminogen-binding activity has been related in other parasites with the facilitation of intra-organic migration, which represents an important fact in avian ascaridiasis. This work represents the first proteomic study of A. galli and could contribute to explain some aspects of parasite/host relationships of avian ascaridiasis. Copyright © 2013 Elsevier B.V. All rights reserved.

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

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    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.

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

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    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.

  10. Lack of viable parasites in cured 'Parma Ham' (PDO), following experimental Toxoplasma gondii infection of pigs.

    Science.gov (United States)

    Genchi, Marco; Vismarra, Alice; Mangia, Carlo; Faccini, Silvia; Vicari, Nadia; Rigamonti, Sara; Prati, Paola; Marino, Anna Maria; Kramer, Laura; Fabbi, Massimo

    2017-09-01

    Twelve Large White pigs were experimentally infected with 1000 Toxoplasma gondii oocysts/each. Serology was carried out at different time points post infection (p.i.) and animals were slaughtered at four months p.i. One of two thighs was examined for T. gondii infection status by PCR and bioassay in mice. The other thigh was processed for Parma ham production. Four thighs were examined after twelve months of curing, four after fourteen months and four were examined after sixteen months. Cured hams were analyzed by PCR, bioassay and in-vitro cultivation on Vero cells followed by real-time PCR. Pigs seroconverted from day 21 p.i. Bioassays were positive for all fresh thighs, but negative for cured hams. PCR was positive for parasite DNA from most thighs both at slaughter and post curing, but parasite growth was not observed following in vitro cultivation and real-time PCR. Results indicate that the curing process of Parma Ham (PDO), when carried out according to the Parma Ham consortium regulations, can inactivate T. gondii tissue cysts. Results would suggest that food-borne transmission of T. gondii to consumers from Parma ham can be excluded. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Lipid A's structure mediates Neisseria gonorrhoeae fitness during experimental infection of mice and men.

    Science.gov (United States)

    Hobbs, Marcia M; Anderson, James E; Balthazar, Jacqueline T; Kandler, Justin L; Carlson, Russell W; Ganguly, Jhuma; Begum, Afrin A; Duncan, Joseph A; Lin, Jessica T; Sparling, P Frederick; Jerse, Ann E; Shafer, William M

    2013-11-19

    Phosphoethanolamine (PEA) on Neisseria gonorrhoeae lipid A influences gonococcal inflammatory signaling and susceptibility to innate host defenses in in vitro models. Here, we evaluated the role of PEA-decorated gonococcal lipid A in competitive infections in female mice and in male volunteers. We inoculated mice and men with mixtures of wild-type N. gonorrhoeae and an isogenic mutant that lacks the PEA transferase, LptA. LptA production conferred a marked survival advantage for wild-type gonococci in the murine female genital tract and in the human male urethra. Our studies translate results from test tube to animal model and into the human host and demonstrate the utility of the mouse model for studies of virulence factors of the human-specific pathogen N. gonorrhoeae that interact with non-host-restricted elements of innate immunity. These results validate the use of gonococcal LptA as a potential target for development of novel immunoprophylactic strategies or antimicrobial treatments. Gonorrhea is one of the most common bacterial sexually transmitted infections, and increasing antibiotic resistance threatens the use of currently available antimicrobial therapies. In this work, encompassing in vitro studies and in vivo studies of animal and human models of experimental genital tract infection, we document the importance of lipid A's structure, mediated by a single bacterial enzyme, LptA, in enhancing the fitness of Neisseria gonorrhoeae. The results of these studies suggest that novel agents targeting LptA may offer urgently needed prevention or treatment strategies for gonorrhea.

  12. Experimental West Nile Virus Infection in Rabbits: An Alternative Model for Studying Induction of Disease and Virus Control

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    Willy W. Suen

    2015-07-01

    Full Text Available The economic impact of non-lethal human and equine West Nile virus (WNV disease is substantial, since it is the most common presentation of the infection. Experimental infection with virulent WNV strains in the mouse and hamster models frequently results in severe neural infection and moderate to high mortality, both of which are not representative features of most human and equine infections. We have established a rabbit model for investigating pathogenesis and immune response of non-lethal WNV infection. Two species of rabbits, New Zealand White (Oryctolagus cuniculus and North American cottontail (Sylvilagus sp., were experimentally infected with virulent WNV and Murray Valley encephalitis virus strains. Infected rabbits exhibited a consistently resistant phenotype, with evidence of low viremia, minimal-absent neural infection, mild-moderate neuropathology, and the lack of mortality, even though productive virus replication occurred in the draining lymph node. The kinetics of anti-WNV neutralizing antibody response was comparable to that commonly seen in infected horses and humans. This may be explained by the early IFNα/β and/or γ response evident in the draining popliteal lymph node. Given this similarity to the human and equine disease, immunocompetent rabbits are, therefore, a valuable animal model for investigating various aspects of non-lethal WNV infections.

  13. Experimental West Nile Virus Infection in Rabbits: An Alternative Model for Studying Induction of Disease and Virus Control

    Science.gov (United States)

    Suen, Willy W.; Uddin, Muhammad J.; Wang, Wenqi; Brown, Vienna; Adney, Danielle R.; Broad, Nicole; Prow, Natalie A.; Bowen, Richard A.; Hall, Roy A.; Bielefeldt-Ohmann, Helle

    2015-01-01

    The economic impact of non-lethal human and equine West Nile virus (WNV) disease is substantial, since it is the most common presentation of the infection. Experimental infection with virulent WNV strains in the mouse and hamster models frequently results in severe neural infection and moderate to high mortality, both of which are not representative features of most human and equine infections. We have established a rabbit model for investigating pathogenesis and immune response of non-lethal WNV infection. Two species of rabbits, New Zealand White (Oryctolagus cuniculus) and North American cottontail (Sylvilagus sp.), were experimentally infected with virulent WNV and Murray Valley encephalitis virus strains. Infected rabbits exhibited a consistently resistant phenotype, with evidence of low viremia, minimal-absent neural infection, mild-moderate neuropathology, and the lack of mortality, even though productive virus replication occurred in the draining lymph node. The kinetics of anti-WNV neutralizing antibody response was comparable to that commonly seen in infected horses and humans. This may be explained by the early IFNα/β and/or γ response evident in the draining popliteal lymph node. Given this similarity to the human and equine disease, immunocompetent rabbits are, therefore, a valuable animal model for investigating various aspects of non-lethal WNV infections. PMID:26184326

  14. 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

    2018-01-23

    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

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

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    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.

  16. Airway inflammation and illness severity in response to experimental rhinovirus infection in asthma.

    Science.gov (United States)

    Zhu, Jie; Message, Simon D; Qiu, Yusheng; Mallia, Patrick; Kebadze, Tatiana; Contoli, Marco; Ward, Christine K; Barnathan, Elliot S; Mascelli, Mary Ann; Kon, Onn M; Papi, Alberto; Stanciu, Luminita A; Jeffery, Peter K; Johnston, Sebastian L

    2014-06-01

    The nature of bronchial mucosal inflammation and its physiologic and clinical significance in rhinovirus-induced asthma exacerbations is unclear. We investigated bronchial mucosal inflammatory response and its association with physiologic and clinical outcomes in an experimental model of rhinovirus-induced asthma exacerbations. We used immunohistochemistry methods to detect phenotypes of inflammatory cells infiltrating the bronchial mucosa before and after experimental rhinovirus infection in 10 subjects with asthma and 15 normal subjects. Compared with baseline, rhinovirus infection significantly increased the number of epithelial (P = .005) and subepithelial (P = .017) neutrophils in subjects with asthma only and subepithelial CD68+ macrophages in both subjects with asthma (P = .009) and normal subjects (P = .018) but more so in those with asthma (P = .021). Numbers of CD45+, CD68+, and CD20+ cells; neutrophils; and eosinophils at day 4 postinfection were positively associated with virus load (r = 0.50-0.72, P = .016-0.03). At acute infection in subjects with asthma, CD4+ cells correlated with chest symptom scores (r = 0.69, P = .029), the fall in the 10% fall in FEV1 (PC10) correlated with neutrophils (r = -0.89, P = .029), the PC10 correlated inversely with CD4+ (r = -0.67, P = .023) and CD8+ cells (r = -0.65, P = .03), the 20% fall in FEV1 was inversely associated with CD20+ cells (r = -0.65, P = .03), and higher epithelial CD8+ cell counts were significantly associated with a greater maximum fall in FEV1 (r = -0.72, P = .03), whereas higher subepithelial mast cell counts were significantly associated with a lower maximum percent fall in peak expiratory flow (r = 0.8, P = .024). In subjects with asthma, rhinovirus infection induces bronchial mucosal neutrophilia and more severe monocyte/macrophage infiltration than in normal subjects. Airway neutrophils, eosinophils, and T and B lymphocytes during infection are related to virus load and physiologic and

  17. ICAM-1-based rabies virus vaccine shows increased infection and activation of primary murine B cells in vitro and enhanced antibody titers in-vivo.

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    James E Norton

    Full Text Available We have previously shown that live-attenuated rabies virus (RABV-based vaccines infect and directly activate murine and human primary B cells in-vitro, which we propose can be exploited to help develop a single-dose RABV-based vaccine. Here we report on a novel approach to utilize the binding of Intracellular Adhesion Molecule-1 (ICAM-1 to its binding partner, Lymphocyte Function-associated Antigen-1 (LFA-1, on B cells to enhance B cell activation and RABV-specific antibody responses. We used a reverse genetics approach to clone, recover, and characterize a live-attenuated recombinant RABV-based vaccine expressing the murine Icam1 gene (rRABV-mICAM-1. We show that the murine ICAM-1 gene product is incorporated into virus particles, potentially exposing ICAM-1 to extracellular binding partners. While rRABV-mICAM-1 showed 10-100-fold decrease in viral titers on baby hamster kidney cells compared to the parental virus (rRABV, rRABV-mICAM-1 infected and activated primary murine B cells in-vitro more efficiently than rRABV, as indicated by significant upregulation of CD69, CD40, and MHCII on the surface of infected B cells. ICAM-1 expression on the virus surface was responsible for enhanced B cell infection since pre-treating rRABV-mICAM-1 with a neutralizing anti-ICAM-1 antibody reduced B cell infection to levels observed with rRABV alone. Furthermore, 100-fold less rRABV-mICAM-1 was needed to induce antibody titers in immunized mice equivalent to antibody titers observed in rRABV-immunized mice. Of note, only 10(3 focus forming units (ffu/mouse of rRABV-mICAM-1 was needed to induce significant anti-RABV antibody titers as early as five days post-immunization. As both speed and potency of antibody responses are important in controlling human RABV infection in a post-exposure setting, these data show that expression of Icam1 from the RABV genome, which is then incorporated into the virus particle, is a promising strategy for the development of a

  18. ICAM-1-based rabies virus vaccine shows increased infection and activation of primary murine B cells in vitro and enhanced antibody titers in-vivo.

    Science.gov (United States)

    Norton, James E; Lytle, Andrew G; Shen, Shixue; Tzvetkov, Evgeni P; Dorfmeier, Corin L; McGettigan, James P

    2014-01-01

    We have previously shown that live-attenuated rabies virus (RABV)-based vaccines infect and directly activate murine and human primary B cells in-vitro, which we propose can be exploited to help develop a single-dose RABV-based vaccine. Here we report on a novel approach to utilize the binding of Intracellular Adhesion Molecule-1 (ICAM-1) to its binding partner, Lymphocyte Function-associated Antigen-1 (LFA-1), on B cells to enhance B cell activation and RABV-specific antibody responses. We used a reverse genetics approach to clone, recover, and characterize a live-attenuated recombinant RABV-based vaccine expressing the murine Icam1 gene (rRABV-mICAM-1). We show that the murine ICAM-1 gene product is incorporated into virus particles, potentially exposing ICAM-1 to extracellular binding partners. While rRABV-mICAM-1 showed 10-100-fold decrease in viral titers on baby hamster kidney cells compared to the parental virus (rRABV), rRABV-mICAM-1 infected and activated primary murine B cells in-vitro more efficiently than rRABV, as indicated by significant upregulation of CD69, CD40, and MHCII on the surface of infected B cells. ICAM-1 expression on the virus surface was responsible for enhanced B cell infection since pre-treating rRABV-mICAM-1 with a neutralizing anti-ICAM-1 antibody reduced B cell infection to levels observed with rRABV alone. Furthermore, 100-fold less rRABV-mICAM-1 was needed to induce antibody titers in immunized mice equivalent to antibody titers observed in rRABV-immunized mice. Of note, only 10(3) focus forming units (ffu)/mouse of rRABV-mICAM-1 was needed to induce significant anti-RABV antibody titers as early as five days post-immunization. As both speed and potency of antibody responses are important in controlling human RABV infection in a post-exposure setting, these data show that expression of Icam1 from the RABV genome, which is then incorporated into the virus particle, is a promising strategy for the development of a single-dose RABV

  19. An in vitro experimental model of neuroinflammation: the induction of interleukin-6 in murine astrocytes infected with Theiler's murine encephalomyelitis virus, and its inhibition by oestrogenic receptor modulators

    Science.gov (United States)

    Rubio, Nazario; Cerciat, Marie; Unkila, Mikko; Garcia-Segura, Luis M; Arevalo, Maria-Angeles

    2011-01-01

    This paper describes an experimental model of neuroinflammation based on the production of interleukin-6 (IL-6) by neural glial cells infected with Theiler's murine encephalomyelitis virus (TMEV). Production of IL-6 mRNA in mock-infected and TMEV-infected SJL/J murine astrocytes was examined using the Affymetrix murine genome U74v2 DNA microarray. The IL-6 mRNA from infected cells showed an eightfold increase in hybridization to a sequence encoding IL-6 located on chromosome number 5. Quantitative real-time reverse transcription PCR (qPCR) was used to study the regulation of IL-6 expression. The presence of IL-6 in the supernatants of TMEV-infected astrocyte cultures was quantified by ELISA and found to be weaker than in cultures of infected macrophages. The IL-6 was induced by whole TMEV virions, but not by Ad.βGal adenovirus, purified TMEV capsid proteins, or UV-inactivated virus. Two recombinant inflammatory cytokines, IL-1α and tumour necrosis factor-α were also found to be potent inducers of IL-6. The secreted IL-6 was biologically active because it fully supported B9 hybridoma proliferation in a [3H]thymidine incorporation bioassay. The cerebrospinal fluid of infected mice contained IL-6 during the acute encephalitis phase, peaking at days 2–4 post-infection. Finally, this in vitro neuroinflammation model was fully inhibited, as demonstrated by ELISA and qPCR, by five selective oestrogen receptor modulators. PMID:21564094

  20. Experimental Infection of Calves by Two Genetically-Distinct Strains of Rift Valley Fever Virus

    Directory of Open Access Journals (Sweden)

    William C. Wilson

    2016-05-01

    Full Text Available Recent outbreaks of Rift Valley fever in ruminant livestock, characterized by mass abortion and high mortality rates in neonates, have raised international interest in improving vaccine control strategies. Previously, we developed a reliable challenge model for sheep that improves the evaluation of existing and novel vaccines in sheep. This sheep model demonstrated differences in the pathogenesis of Rift Valley fever virus (RVFV infection between two genetically-distinct wild-type strains of the virus, Saudi Arabia 2001 (SA01 and Kenya 2006 (Ken06. Here, we evaluated the pathogenicity of these two RVFV strains in mixed breed beef calves. There was a transient increase in rectal temperatures with both virus strains, but this clinical sign was less consistent than previously reported with sheep. Three of the five Ken06-infected animals had an early-onset viremia, one day post-infection (dpi, with viremia lasting at least three days. The same number of SA01-infected animals developed viremia at 2 dpi, but it only persisted through 3 dpi in one animal. The average virus titer for the SA01-infected calves was 1.6 logs less than for the Ken06-infected calves. Calves, inoculated with either strain, seroconverted by 5 dpi and showed time-dependent increases in their virus-neutralizing antibody titers. Consistent with the results obtained in the previous sheep study, elevated liver enzyme levels, more severe liver pathology and higher virus titers occurred with the Ken06 strain as compared to the SA01 strain. These results demonstrate the establishment of a virulent challenge model for vaccine evaluation in calves.

  1. Experimental infection of hamsters with avian paramyxovirus serotypes 1 to 9

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    Samuel Arthur S

    2011-02-01

    Full Text Available Abstract Avian paramyxoviruses (APMVs are frequently isolated from domestic and wild birds throughout the world and are separated into nine serotypes (APMV-1 to -9. Only in the case of APMV-1, the infection of non-avian species has been investigated. The APMVs presently are being considered as human vaccine vectors. In this study, we evaluated the replication and pathogenicity of all nine APMV serotypes in hamsters. The hamsters were inoculated intranasally with each virus and monitored for clinical disease, pathology, histopathology, virus replication, and seroconversion. On the basis of one or more of these criteria, each of the APMV serotypes was found to replicate in hamsters. The APMVs produced mild or inapparent clinical signs in hamsters except for APMV-9, which produced moderate disease. Gross lesions were observed over the pulmonary surface of hamsters infected with APMV-2 & -3, which showed petechial and ecchymotic hemorrhages, respectively. Replication of all of the APMVs except APMV-5 was confirmed in the nasal turbinates and lungs, indicating a tropism for the respiratory tract. Histologically, the infection resulted in lung lesions consistent with bronchointerstitial pneumonia of varying severity and nasal turbinates with blunting or loss of cilia of the epithelium lining the nasal septa. The majority of APMV-infected hamsters exhibited transient histological lesions that self resolved by 14 days post infection (dpi. All of the hamsters infected with the APMVs produced serotype-specific HI or neutralizing antibodies, confirming virus replication. Taken together, these results demonstrate that all nine known APMV serotypes are capable of replicating in hamsters with minimal disease and pathology.

  2. Analysis of Heavy-Chain Antibody Responses and Resistance to Parelaphostrongylus tenuis in Experimentally Infected Alpacas

    Science.gov (United States)

    Purdy, S. R.; Gagliardo, L. F.; Lefman, S.; Hamel, P. J. S.; Ku, S.; Mainini, T.; Hoyt, G.; Justus, K.; Daley-Bauer, L. P.; Duffy, M. S.

    2012-01-01

    The parasitic nematode Parelaphostrongylus tenuis is an important cause of neurologic disease of camelids in central and eastern North America. The aim of this study was to determine whether alpacas develop resistance to disease caused by P. tenuis in response to a previous infection or a combination of controlled infection and immunization. Alpacas were immunized with a homogenate of third-stage larvae (L3) and simultaneously implanted subcutaneously with diffusion chambers containing 20 live L3. Sham-treated animals received adjuvant alone and empty chambers. The protocol was not effective in inducing resistance to oral challenge with 10 L3, and disease developed between 60 and 71 days following infection. Immediately following the onset of neurologic disease, affected animals were treated with a regimen of anthelmintic and anti-inflammatory drugs, and all recovered. One year later, a subset of alpacas from this experiment was challenged with 20 L3 and the results showed that prior infection induced resistance to disease. Primary and secondary infections induced production of conventional and heavy-chain IgGs that reacted with soluble antigens in L3 homogenates but did not consistently recognize a recombinant form of a parasite-derived aspartyl protease inhibitor. Thus, the latter antigen may not be a good candidate for serology-based diagnostic tests. Antibody responses to parasite antigens occurred in the absence of overt disease, demonstrating that P. tenuis infection can be subclinical in a host that has been considered to be highly susceptible to disease. The potential for immunoprophylaxis to be effective in preventing disease caused by P. tenuis was supported by evidence of resistance to reinfection. PMID:22593238

  3. Restricted expression of Borna disease virus glycoprotein in brains of experimentally infected Lewis rats.

    Science.gov (United States)

    Werner-Keiss, N; Garten, W; Richt, J A; Porombka, D; Algermissen, D; Herzog, S; Baumgärtner, W; Herden, C

    2008-12-01

    Borna disease virus (BDV) induces a persistent infection in the central nervous system (CNS) accompanied by a non-purulent meningoencephalitis. BDV-infection of Lewis rats provides an important model to investigate basic principles of neurotropism, viral persistence and resulting dysfunctions. To date, the in vivo strategies of BDV to persist in the CNS are not fully understood. Viral glycoproteins are main targets of the antiviral defence implicating a controlled expression in case of persistent infections. Therefore, we analysed the expression profiles of the BDV-glycoprotein (BDV-GP) and corresponding BDV-intron II RNA in experimentally infected rat brains, focusing on their spatio-temporal occurrence, regional, cellular and intracellular locations. This was carried out by immunohistochemistry and in situ hybridization. The expression pattern of the most abundantly expressed BDV-nucleoprotein (BDV-N) served as a reference. BDV-N mRNA was detected preferentially in the cytoplasm of neurones, whereas BDV-intron II mRNA was found predominantly in the nucleus of brain cells. The genomic RNA was restricted to the nucleus. Expression of BDV-GP was significantly lower than BDV-N expression and mainly limited to cerebral cortex, hippocampus, amygdala and thalamus. BDV-GP was restricted to larger neurones; BDV-N occurred also in astrocytes, oligodendrocytes and ependymal cells. The expression profiles of BDV-GP, BDV-N and their mRNAs are significantly different, indicating that BDV-GP expression is regulated in vivo. This might be achieved by restricted nuclear export and/or maturation of BDV-intron II mRNA or limited translation as a viral mechanism to escape from the immune response and enable persistence in the CNS.

  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. Intrahepatic Vγ9Vδ2 T-cells from HCV-infected patients show an exhausted phenotype but can inhibit HCV replication.

    Science.gov (United States)

    Cimini, E; Bordoni, V; Sacchi, A; Visco-Comandini, U; Montalbano, M; Taibi, C; Casetti, R; Lalle, E; D'Offizi, G; Capobianchi, M R; Agrati, C

    2018-01-02

    Hepatitis C virus (HCV) persistence results from inefficiencies of both innate and adaptive immune responses to eradicate the infection. A functional impairment of circulating Vγ9Vδ2 T-cells was described but few data are available on Vγ9Vδ2 T-cells in the liver that, however, represents the battlefield in the HCV/host interaction. Aim of this work was to compare circulating and intrahepatic Vγ9Vδ2 T-cells in chronic HCV-infected patients (HCVpos) and in HCV-negative (HCVneg) subjects. Phenotypic and functional analysis was performed by flow cytometry. Anti-HCV activity was analyzed by using an in vitro autologous liver culture system. Independently from HCV infection, the liver was enriched of Vγ9Vδ2 T-cells expressing an effector/activated phenotype. In contrast, an enrichment of PD-1 expressing Vγ9Vδ2 T-cells was observed both in the peripheral blood and in the liver of HCVpos patients, probably due to a persistent antigenic stimulation. Moreover, a lower frequency of IFN-γ producing Vγ9Vδ2 T-cells was observed in the liver of HCVpos patients, suggesting a functional impairment in the cytokine production in HCVpos liver. Despite this hypo-responsiveness, intrahepatic Vγ9Vδ2 T-cells are able to exert an anti-HCV activity after specific stimulation. Altogether, our data show that HCV infection induced a dysregulation of intrahepatic Vγ9Vδ2 T cells that maintain their anti-HCV activity after specific stimulation. A study aimed to evaluate the mechanisms of the antiviral activity may be useful to identify new pathways able to improve Vγ9Vδ2 T-cells intrahepatic function during HCV infection. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Molecular characterisation of the early response in pigs to experimental infection with Actinobacillus pleuropneumoniae using cDNA microarrays

    DEFF Research Database (Denmark)

    Hedegaard, Jakob; Skovgaard, Kerstin; Mortensen, Shila

    2007-01-01

    of this study was hence to characterise the transcriptional response, measured by using cDNA microarrays, in pigs 24 hours after experimental inoculation with A. pleuropneumoniae. Methods: Microarray analyses were conducted to reveal genes being differentially expressed in inflamed versus non-inflamed lung......-infected animals and 130 genes differed in expression in tracheobronchial lymph node tissue from infected versus non-infected animals. Among these genes, several have previously been described to be part of a general host response to infections encoding immune response related proteins. In inflamed lung tissue...

  7. Influence of etoposide and cyclophosphamide on the efficacy of cloxacillin and erythromycin in an experimental staphylococcal infection.

    Science.gov (United States)

    Calame, W; van der Waals, R; Mattie, H; van Furth, R

    1989-01-01

    The effect of monocytopenia and granulocytopenia on the outgrowth of Staphylococcus aureus as well as on antibiotic efficacy was studied in an experimental thigh infection in mice. Pretreatment with etoposide reduced monocyte numbers in blood to 14% and those of granulocytes to 54% at the time of infection. Monocytopenia did not affect the proliferation of bacteria in the infected thigh or the reduction of bacterial numbers after treatment with cloxacillin or erythromycin. Pretreatment with cyclophosphamide reduced monocyte numbers to 15% and granulocyte numbers to 3%. This resulted in a marked increase in the number of bacteria at the site of infection and a decrease in the efficacy of antibiotic treatment. PMID:2764550

  8. Energy deficit does not affect immune responses of experimentally infected pacu (Piaractus mesopotamicus).

    Science.gov (United States)

    Gimbo, Rodrigo Y; Fávero, Gisele C; Franco Montoya, Luz N; Urbinati, Elisabeth C

    2015-04-01

    We investigated if the energy deficit following a 30-day starvation period could affect the ability of fish to mount immune responses after experimental exposure to Aeromonas hydrophila. Fish were submitted to two feeding strategies during 30 days: starvation and continuously feeding. Fish were then sampled to allow for the assessment of baseline metabolic and immune system indicators, were next intraperitonially inoculated with A. hydrophila, and finally were sampled at 3 and 24 h after the challenge. The respiratory activity of leukocytes was lower in starved fish at baseline, increasing after bacterial inoculation to levels similar to those seen among fed fish. Levels of serum lysozyme were higher in starved fish at baseline. The same response profile was observed 3 h after inoculation, but among fed fish, these levels increased to values similar to those of starved fish 24 h after infection. Among starved fish, lysozyme concentration did not change over the course of the experiment. The serum ACH activity was lower in starved fish at baseline and increased after bacterial inoculation in both fish groups. Baseline levels of blood glucose of starved fish were lower than those of fed fish and increased 3 h after bacterial inoculation in both fish groups, decreasing in both groups at 24 h after inoculation. Baseline liver glycogen levels were similar in both fish groups and higher than at 3 and 24 h after inoculation. Three hours after bacterial inoculation, liver glycogen was less reduced in fed fish. Baseline levels of blood triglycerides were lower in starved fish and the profile remained unchanged 3 h after inoculation. There was a gradual decrease in fed fish, and the levels of starved fish remained unchanged throughout the observation period. Blood glycerol levels at baseline were higher in starved fish than in fed fish and remained unaltered at 3 h after inoculation. However those levels increased at 24 h. In fed fish there was a gradual increase of

  9. Activity of synthetic chalcones in hamsters experimentally infected with Leishmania (Viannia) braziliensis.

    Science.gov (United States)

    de Mello, Tatiane F P; Cardoso, Bruna M; Lopes, Sara N; Bitencourt, Heriberto R; Voltarelli, Evandra M; Hernandes, Luzmarina; Aristides, Sandra M A; Lonardoni, Maria V C; Silveira, Thais G V

    2015-10-01

    The purpose of this study is to evaluate the toxicity of synthetic chalcones 1 and 2 in uninfected hamsters and anti-Leishmania activity of synthetic chalcones 1 and 2 in hamsters infected with Leishmania (Viannia) braziliensis. For the toxicity test, uninfected animals were treated with chalcones 1 and 2, and clinical and biochemical parameters and histological aspects of the liver and kidneys were assessed. Chalcones 1 and 2 were then intraperitoneally or topically administered (10 mg/kg body weight) three times per week in animals infected with promastigotes of L. (V.) braziliensis. We monitored the thickness of the infected footpads, determined parasitic load, performed histological analysis, and detected apoptosis in situ. The results were analyzed using Student's t test and Mann-Whitney test at a significance level of 5%. Neither of the chalcones showed toxicity. Chalcone 2 administered intraperitoneally significantly reduced the thickness of the infected footpad compared with the beginning of treatment. The parasite load of the lymph node and spleen was reduced in the groups treated with chalcones 1 (topical) and 2 (intraperitoneal). Chalcone 2 (topical) reduced parasite burden only in the lymph node. The histological analysis revealed reconstitution of the tissue and reductions of inflammation and apoptosis in the infected footpad in these groups. The synthetic chalcones 1 (topical) and 2 (intraperitoneal and topical) at a dose of 10 mg/kg showed anti-Leishmania activity in vivo, no renal or hepatic toxicity, and a reduction of apoptosis of the cells in the lesions. These chalcones may have substantial potential for the treatment of cutaneous leishmaniasis.

  10. ITIH4 (inter-alpha-trypsin inhibitor heavy chain 4) is a new acute-phase protein isolated from cattle during experimental infection

    DEFF Research Database (Denmark)

    Pineiro, M.; Andres, M.; Iturralde, M.

    2004-01-01

    , and Peptostreptococcus indolicus to induce an acute-phase reaction. All animals developed moderate to severe clinical mastitis and exhibited remarkable increases in ITIH4 concentration in serum (from 3 to 12 times the initial values, peaking at 48 to 72 h after infection) that correlated with the severity of the disease....... Animals with experimental infections with bovine respiratory syncytial virus (BRSV) also showed increases in ITIH4 concentration (from two- to fivefold), which peaked at around 7 to 8 days after inoculation. Generally, no response was seen after a second infection of the same animals with the virus....... Because of the significant induction of the protein in the animals in the mastitis and BRSV infection models, we can conclude that ITIH4 is a new positive acute-phase protein in cattle....

  11. Immunization of pigs against experimental Ascaris suum infection by feeding ultraviolet-attenuated eggs

    Energy Technology Data Exchange (ETDEWEB)

    Tromba, F.G.

    1978-08-01

    Pigs fed Ascaris suum eggs attenuated by short-wave ultraviolet radiation developed a resistance to challenge infections that varied according to the protocols used. An analysis of the lengths of worms recovered showed that in controls fed varying doses of eggs, worm sizes were inversely related to the number of eggs in the challenge dose. A ratio of 18 female to 5 male worms indicated that males are more susceptible to ultraviolet radiation than females.

  12. Decal bone matrix as a local antibiotic delivery vehicle in a MRSA-infected bone model: An experimental study

    Directory of Open Access Journals (Sweden)

    Saraf Shyam

    2010-01-01

    Full Text Available Background: Polymethyl methacrylate (PMMA antibiotic beads though have proved their utility as a local antibiotic delivery system, however, there are limitations. Decalcified bone matrix (DBM as a vehicle of antibiotics can serve the purpose, provided a minimum inhibitory concentration is sustained. Healing of the defect and avoiding the second surgery is another advantage. We studied the DBM as the delivery vehicle for vancomycin in controlling the methicillin-resistant Staphylococcus aureus (MRSA osteomyelitis as well as healing of the cavity simultaneously in an experimental study. Materials and Methods: An in vitro study was conducted to optimize vancomycin impregnation in the DBM. For the in vivo study, a unicortical defect was created in the metaphysis of the distal femur in 18 rabbits. After contaminating the defect with MRSA, rabbits were divided into three groups. Group I (eight limbs received no graft. Defects in group II (11 limbs were filled with plain DBM chips and in group III (14 limbs, cavities were implanted with vancomycin-impregnated decal bone chips. Rabbits were assessed by clinical, radiological, histological, gross examination and bacterial load assay. High Performance Liquid Chromatography HPLC analysis of vancomycin in group III was done to assess the concentration in DBM chips. Results: In group I, the infection persisted throughout the period of the study. Group II showed the fulminated infection at the grafted site with DBM chips sequestrating out. Vancomycin-impregnated decal chips in group III did not show any sign of infection and eventually incorporated. The bacterial load study showed a progressive load change and HPLC revealed an effective antibiotic concentration up to 3 weeks in both in vitro and in vivo. Conclusion: Decal bone chips were effective as the local antibiotic delivery vehicle in preventing the MRSA osteomyelitis model. It eluted vancomycin significantly and the graft uptake was also excellent

  13. Detection and dissemination of Toxoplasma gondii in experimentally infected calves, a single test does not tell the whole story.

    Science.gov (United States)

    Burrells, Alison; Taroda, Alessandra; Opsteegh, Marieke; Schares, Gereon; Benavides, Julio; Dam-Deisz, Cecile; Bartley, Paul M; Chianini, Francesca; Villena, Isabella; van der Giessen, Joke; Innes, Elisabeth A; Katzer, Frank

    2018-01-18

    Although the detection of Toxoplasma gondii in bovine tissues is rare, beef might be an important source of human infection. The use of molecular techniques, such as magnetic capture qPCR (MC-qPCR), in combination with the gold standard method for isolating the parasite (mouse bioassay), may increase the sensitivity of T. gondii detection in infected cattle. The risk of transmission of the parasite to humans from undercooked/raw beef is not fully known and further knowledge about the predilection sites of T. gondii within cattle is needed. In the current study, six Holstein Friesian calves (Bos taurus) were experimentally infected with 10 6  T. gondii oocysts of the M4 strain and, following euthanasia (42 dpi), pooled tissues were tested for presence of the parasite by mouse bioassay and MC-qPCR. Toxoplasma gondii was detected by both MC-qPCR and mouse bioassay from distinct pools (100 g) of tissues comprising: liver, tongue, heart, diaphragm, semitendinosus (hindlimb), longissimus dorsi muscle (sirloin) and psoas major muscle (fillet). When a selection of individual tissues which had been used for mouse bioassay were examined by MC-qPCR, parasite DNA could only be detected from two animals, despite all calves showing seroconversion after infection. It is apparent that one individual test will not provide an answer as to whether a calf harbours T. gondii tissue cysts. Although the calves received a known number of infectious oocysts and highly sensitive methods for the detection of the parasite within bovine tissues were applied (mouse bioassay and MC-qPCR), the results confirm previous studies which report low presence of viable T. gondii in cattle and no clear predilection site within bovine tissues.

  14. Infecção experimental em cabritos pelo vírus da artrite encefalite Caprine arthritis encephalitis virus experimental infection in new-born kids

    Directory of Open Access Journals (Sweden)

    M.I.M.C. Guedes

    2001-02-01

    Full Text Available Vinte e quatro caprinos de uma semana de idade, soronegativos pela imunodifusão em gel de agar para artrite encefalite caprina (AEC, foram utilizados para estudo de infecção experimental pelo vírus da AEC. Dezesseis animais foram inoculados com lentivirus caprino, amostra Cork, oito pela via intravenosa e oito por instilação nasal. Oito animais serviram como controle, inoculados pelas vias intranasal ou intravenosa com 1ml de meio de cultura de células não infectadas. Os animais foram sacrificados aos 2, 6, 12 e 20 dias pós-inoculação (PI, e colhidas amostras do sistema nervoso central, articulações, tonsilas, linfonodos, pulmões, rins, timo, baço e intestinos delgado e grosso para histopatologia e imunoistoquímica. Um animal inoculado com o vírus da AEC pela via intranasal e sacrificado aos 20 dias PI apresentou imunomarcação positiva em um macrófago alveolar. Concluiu-se que a via aerógena é uma provável rota de infecção pelo vírus da AEC.The caprine arthritis encephalitis virus (CAEV experimental infection was studied in 24 one-week-old seronegative kids. Sixteen kids were inoculated with CAEV-Cork, with 10(6 TCID50/ml concentration, being eight inoculated intravenously, and eight intranasally. Eight animals were used as controls, being four inoculated intravenously, and four intranasally with non-infected cell culture medium. Since the day of the inoculation, clinical evaluation was performed daily, until the day of the sacrifice. Blood samples were taken for serological tests. The animals were killed in pairs at 2, 6, 12 and 20 days post-inoculation (PI and tissues samples of central nervous system, joints, tonsils, lymphonodes, lungs, kidneys, thymus, spleen, small and large intestine were collected for histopathological and immunohistochemical studies. One animal CAEV inoculated intranasally and killed at 20 days PI showed immunohistochemical positive reaction in an alveolar macrophage. It was concluded that

  15. Cutaneous manifestations of B-cell chronic lymphocytic leukemia associated with Borrelia burgdorferi infection showing a marginal zone B-cell lymphoma-like infiltrate.

    Science.gov (United States)

    Kash, Natalie; Fink-Puches, Regina; Cerroni, Lorenzo

    2011-10-01

    We report on a 69-year-old female patient with specific cutaneous manifestations of B-cell chronic lymphocytic leukemia that arose at the site of erythema chronicum migrans due to Borrelia burgdorferi infection. Histological examination revealed the presence of dense infiltrates of small hyperchromatic lymphocytes admixed with clusters of plasma cells. Immunohistology showed a CD5+/CD20+ phenotype of the lymphocytes and monoclonal expression of kappa immunoglobulin light chain by the plasma cells. Presence of Borrelia DNA was confirmed by polymerase chain reaction studies. The unusual histopathological and phenotypic findings described in this case of cutaneous manifestations of B-cell chronic lymphocytic leukemia associated with Borrelia burgdorferi infection may lead to the misdiagnosis of cutaneous marginal zone B-cell lymphoma.

  16. Haemophilus parainfluenzae Strain ATCC 33392 Forms Biofilms In Vitro and during Experimental Otitis Media Infections.

    Science.gov (United States)

    Pang, Bing; Swords, W Edward

    2017-09-01

    Haemophilus parainfluenzae is a nutritionally fastidious, Gram-negative bacterium with an oropharyngeal/nasopharyngeal carriage niche that is associated with a range of opportunistic infections, including infectious endocarditis and otitis media (OM). These infections are often chronic/recurrent in nature and typically involve bacterial persistence within biofilm communities that are highly resistant to host clearance. This study addresses the primary hypothesis that H. parainfluenzae forms biofilm communities that are important determinants of persistence in vivo The results from in vitro biofilm studies confirmed that H. parainfluenzae formed biofilm communities within which the polymeric matrix was mainly composed of extracellular DNA and proteins. Using a chinchilla OM infection model, we demonstrated that H. parainfluenzae formed surface-associated biofilm communities containing bacterial and host components that included neutrophil extracellular trap (NET) structures and that the bacteria mainly persisted in these biofilm communities. We also used this model to examine the possible interaction between H. parainfluenzae and its close relative Haemophilus influenzae, which is also commonly carried within the same host environments and can cause OM. The results showed that coinfection with H. influenzae promoted clearance of H. parainfluenzae from biofilm communities during OM infection. The underlying mechanisms for bacterial persistence and biofilm formation by H. parainfluenzae and knowledge about the survival defects of H. parainfluenzae during coinfection with H. influenzae are topics for future work. Copyright © 2017 American Society for Microbiology.

  17. Phosphorus kinetics in calves experimentally submitted to a trickle infection with Cooperia punctata.

    Science.gov (United States)

    Louvandini, H; Rodrigues, R R; Gennari, S M; McManus, C M; Vitti, D M S S

    2009-07-07

    Ten male Holstein calves (74.3+/-3.2 kg LW) were used for a trial with trickle infection with Cooperia punctata to evaluate phosphorus (P) kinetics. Five calves were inoculated with 10,000 L(3) stage larvae per week during 35 days, while the other group of five calves was kept as a control. On the 29th day each calf was intravenously injected with 29.6 MBq of a (32)P solution. Blood samples were taken at 24 h periods for 7 days, after which all calves were slaughtered and worms burdens. Faeces, urine and tissue samples were taken for analysis using isotopic dilution and modeling techniques. The number of eggs per gram of faeces (EPG) was 1920+/-168 on 28th day and the total number of worms burdens was 11,131+/-1500. Infected calves showed lower feed intake and live weight gain, as well as lower P intake, absorption and retention than control calves. The P flows between body compartments were lower for blood to gastrointestinal tract (TGI), TGI to blood, blood to soft tissues, bone balance and soft tissue balance in infected calves when compared to the control. The trickle infection of C. punctata affected P metabolism due to the decrease in P retained and live weight due to fall in feed intake.

  18. Different Therapeutic Outcomes of Benznidazole and VNI Treatments in Different Genders in Mouse Experimental Models of Trypanosoma cruzi Infection.

    Science.gov (United States)

    Guedes-da-Silva, F H; Batista, D G J; da Silva, C F; Meuser, M B; Simões-Silva, M R; de Araújo, J S; Ferreira, C G; Moreira, O C; Britto, C; Lepesheva, G I; Soeiro, Maria de Nazaré C

    2015-12-01

    The lack of translation between preclinical assays and clinical trials for novel therapies for Chagas disease (CD) indicates a need for more feasible and standardized protocols and experimental models. Here, we investigated the effects of treatment with benznidazole (Bz) and with the potent experimental T. cruzi CYP51 inhibitor VNI in mouse models of Chagas disease by using different animal genders and parasite strains and employing distinct types of therapeutic schemes. Our findings confirm that female mice are less vulnerable to the infection than males, show that male models are less susceptible to treatment with both Bz and VNI, and thus suggest that male models are much more suitable for selection of the most promising antichagasic agents. Additionally, we have found that preventive protocols (compound given at 1 dpi) result in higher treatment success rates, which also should be avoided during advanced steps of in vivo trials of novel anti-T. cruzi drug candidates. Another consideration is the relevance of immunosuppression methods in order to verify the therapeutic profile of novel compounds, besides the usefulness of molecular diagnostic tools (quantitative PCR) to ascertain compound efficacy in experimental animals. Our study aims to contribute to the development of more reliable methods and decision gates for in vivo assays of novel antiparasitic compounds in order to move them from preclinical to clinical trials for CD. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  19. 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

  20. Optimal times above MICs of ceftibuten and cefaclor in experimental intra-abdominal infections.

    Science.gov (United States)

    Onyeji, C O; Nicolau, D P; Nightingale, C H; Quintiliani, R

    1994-05-01

    The duration of time that serum drug levels remain above the MIC (time above the MIC) for the pathogen has been shown to be the most significant parameter determining the efficacies of beta-lactam antibiotics. In the described study, we investigated the optimal time above the MIC of ceftibuten and cefaclor using a nonneutropenic mouse model of intra-abdominal infections caused by Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, and Streptococcus pneumoniae. The abilities of the drugs to protect mice against the organisms were determined in mouse protection tests, and the doses were fractionated to produce various dosing regimens with different times above the MIC. All drug-organism combinations showed a significant correlation (r > 0.9) between drug efficacy and the time above the MIC. Also, with ceftibuten treatment, the different dosing regimens that produced equal times above the MIC resulted in the same efficacy, whereas with cefaclor, an apparent dose-dependent effect was observed. These results showed that for a 100% recovery from K. pneumoniae and E. coli infections, the optimal times above the MIC with ceftibuten treatment were 2.2 and 1.6 h, respectively. Relatively high doses of both antibiotics were required to ensure recovery from S. pneumoniae infections. In vitro time-kill studies demonstrated that cefaclor exhibits a marked inoculum effect against the pathogens, and there was a concentration-dependent killing at a large inoculum size. On the other hand, ceftibuten showed no inoculum effect. It is suggested that optimization of both dose and time above the MIC appears to be necessary for the treatment of S. aureus infections with cefaclor, and this may apply to other beta-lactams tht exhibit marked inoculum effects.

  1. Dengue virus detection by using reverse transcription-polymerase chain reaction in saliva and progeny of experimentally infected Aedes albopictus from Brazil

    OpenAIRE

    Márcia Gonçalves Castro; Rita Maria Ribeiro Nogueira; Hermann Gonçalves Schatzmayr; Marize Pereira Miagostovich; Ricardo Lourenço-de-Oliveira

    2004-01-01

    Oral susceptibility and vertical transmission of dengue virus type 2 (DENV-2) in an Aedes albopictus sample from Rio de Janeiro was estimated. The infection (36.7%) and transmission (83.3%) rates for Ae. albopictus were higher than those of an Ae. aegypti colony used as control, 32.8 and 60%, respectively. Fourth instar larvae and females descendants of 48.5 and 39.1% of experimentally infected Ae. albopictus showed to harbor the virus. The oral susceptibility and the high capacity to assure ...

  2. Freeze-tolerance of Trichinella muscle larvae in experimentally infected wild boars.

    Science.gov (United States)

    Lacour, Sandrine A; Heckmann, Aurélie; Macé, Pauline; Grasset-Chevillot, Aurélie; Zanella, Gina; Vallée, Isabelle; Kapel, Christian M O; Boireau, Pascal

    2013-05-20

    Freeze-tolerance of encapsulated Trichinella muscle larvae (ML) is mainly determined by Trichinella species, but is also influenced by host species, the age of the infection and the storage time and temperature of the infected meat. Moreover, the freeze-tolerance of the encapsulated species appears to be correlated to the development of thick capsule walls which increases with age. An extended infection period and the muscle composition in some hosts (e.g. herbivores) may provide freeze-avoiding matrices due to high carbohydrate contents. The present experiment compares freeze-tolerance of Trichinella spiralis and Trichinella britovi ML in wild boar meat 24 weeks post inoculation (wpi). Three groups of four wild boars were infected with 200, 2000 or 20,000 ML of T. britovi (ISS 1575), respectively. Additionally, three wild boars were inoculated with 20,000 ML of T. spiralis (ISS 004) and two animals served as negative controls. All wild boars were sacrificed 24 wpi. Muscle samples of 70 g were stored at -21°C for 19, 30 and 56 h, and for 1-8 weeks. Larvae were recovered by artificial digestion. Their mobilities were recorded using Saisam(®) image analysis software and their infectivities were evaluated using mouse bioassays. Samples frozen for 19, 30 and 56 h allowed recovery of mobile ML, but samples frozen for 1 or 2 weeks did not. Correspondingly, only T. spiralis and T. britovi larvae isolated from wild boar meat frozen for 19, 30 and 56 h established in mice. This study showed that freezing at -21°C for 1 week inactivated T. spiralis and T. britovi ML encapsulated in wild boar meat for 24 weeks. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. [Study on hepatocyte apoptosis of domestic pigs experimentally infected with Taenia asiatica and Taenia saginata].

    Science.gov (United States)

    Mou, Rong; Bao, Huai-En; Zhang, Ke; Wu, Jia-Hong; Lang, Shu-Yuan

    2012-10-30

    To investigate apoptosis in liver tissue of the domestic pigs infected with eggs of Taenia asiatica and Taenia saginata. The adult worms of T. asiatica and T. saginata were collected and identified from the taeniasis patients in Dunyun and Congjiang districts, Guizhou province. Eggs were collected from gravid proglottids and prepared by washing and centrifugation. Nineteen 20-day hybrid domestic pigs (Duroc-Yorkshire-Landrace strain) were randomly divided into T. asiatica group (6 pigs), T. saginata group (8 pigs) and control group (5 pigs). Each animal of experimental groups was infected with 1.5 x 10(5) eggs by stomach injection. On day 15, 32, 46 and 74 after infection, animals were sacrificed and liver samples were collected for further experiments. The liver tissues were sliced for glass slides and prepared for ultrathin sections. The apoptosis of hepatocytes was identified by terminal deoxynucleotidyl transferase-mediated dUTP nick and labeling. The morphological features of liver tissue were observed under transmission electron microscope. The infection rate of two experiment groups reached 100%. Better developed cysticerci were found in liver of T. asiatica group than that of T. saginata group, but the liver pathological changes caused by cysticerci were similar. On day 15 and 32 after infection, hydropic degeneration, obvious vacuolization and some balloon-like degeneration were found in hepatocytes, and focal hepatic necrosis was observed. On day 46, spotty necrosis occurred in some local liver tissues. On day 74, main damages were granulomatous reactions surrounding cysticercus and focal liver fibrosis. On day 46, apoptosis index in T. asiatica group [(15.07 +/- 3.42)6%] and T. saginata group [(17.13 +/- 1.62)5%] was considerably higher than that in the control [(9.53 +/- 1.06)%] (P saginata group [(34.20 +/- 0.73)%] was higher than that in the control [(13.60 +/- 2.26)%] (P saginata group was significantly higher than that of T. asiatica group (P

  4. Using experimental de-worming to measure the immunological and pathological impacts of lungworm infection in cane toads

    Directory of Open Access Journals (Sweden)

    Patrick B. Finnerty

    2017-12-01

    Full Text Available The immunological and pathological consequences of parasite infection can be more rigorously assessed from experimental manipulation than from correlational studies of natural infections. We used anthelmintic treatment to experimentally decrease intensities of lungworm infection in captive and free-ranging wild cane toads to assess parasite impacts on host immune responses. First, we administered the anthelmintic drug Ivermectin to both infected and uninfected toads, to distinguish drug effects per se from the impacts of killing lungworms. Worms began dying and decomposing <48 h after injection. The only immunological variables that were affected by anthelmintic treatment were bactericidal capacity of the blood which increased in parasitized toads (presumably triggered by decomposing worms in the lungs, and the phagocytic capacity of blood (which increased in both infected and uninfected toads; the latter effect presumably was caused by the injection of Ivermectin per se rather than removal of parasites. Second, we looked at correlates of variation in the infection intensity induced by de-worming (in both captive and free-ranging toads over an eight-week period. Heavier lungworm infection was associated with increased phagocytic ability of the host's blood, and a reduction in the host's liver mass (and hence, energy stores. Experimental de-worming thus revealed pathological and immunological costs of the presence of lungworms, and of their removal by anthelmintic injection. Keywords: Rhinella marina, Bufo marinus, Host, Parasite, Nematode

  5. Aseptic surgical preparation for upper eyelid blepharoplasty via full-face octenidine antiseptic without antibiotic medication shows effective prophylaxis against post-surgical wound infection.

    Science.gov (United States)

    Matiasek, Johannes; Kienzl, Philip; Otti, Gerlinde R; Turk, Bela R; Djedovic, Gabriel; Rieger, Ulrich M

    2018-02-01

    Blepharoplasty is the third most common plastic surgical procedure in the USA. Due to the emergence of multiresistant bacteria, optimising the antiseptic procedure is crucial. Choice of antiseptics plays an important role as they may cause skin irritation and colouring of disinfected areas. In this study, the use of the aqueous antiseptic octenisept® (octenidine) was evaluated in the outcome of blepharoplasties: incidence of wound dehiscence; haematoma; and infection in correlation with gender, medication, smoking habits and time of year. This retrospective surveillance study included 352 patients (median age 58·3 years). Skin disinfection was performed thrice prior to blepharoplasty. Sutures were removed on day 6. None of the patients suffered from wound infection. The total rate of wound dehiscence was 6·3%, with a higher ratio among male patients. Smokers and patients on anticoagulant medication showed a significantly higher incidence of wound dehiscence. Throughout the year, rates of wound dehiscence were highest in summer. Aseptic surgical preparation for blepharoplasty via full-face scrub with octenisept® without oral antibiotic prophylaxis is well tolerated, with no report of wound infection, which may improve antibiotic stewardship as well as patient comfort. Elective upper eyelid blepharoplasty may ideally be performed in winter. © 2017 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

  6. A chimeric plum pox virus shows reduced spread and cannot compete with its parental wild-type viruses in a mixed infection.

    Science.gov (United States)

    Dietrich, Christof; Al Abdallah, Qusai; Lintl, Lara; Pietruszka, Agnes; Maiss, Edgar

    2007-10-01

    The effect of a recombination event in the genomic 3' end on the biological properties and competitiveness of plum pox virus (PPV) was investigated. Therefore, a fragment spanning the coat protein (CP) coding region and a part of the 3' non-translated region of a non-aphid-transmissible strain of PPV (PPV-NAT) was replaced by the corresponding region of a PPV sour cherry isolate (PPV-SoC). The resulting chimera (PPV-NAT/SoC) caused severe symptoms in Nicotiana benthamiana, resembling those of PPV-NAT. In mixed infections with either of the parental viruses, the chimera PPV-NAT/SoC was less competitive. Labelling experiments with DsRed showed that PPV-NAT/SoC (PPV-NAT/SoC-red) moved more slowly from cell to cell than PPV-NAT (PPV-NAT-red). In mixed infections of PPV-NAT/SoC-red with a green fluorescent protein-expressing PPV-NAT (PPV-NAT-AgfpS), spatial separation of the viruses was observed. These data suggest that, in PPV infections, symptom severity and competitiveness are independent aspects and that spatial separation may contribute to the displacement of a recombinant virus.

  7. Experimental infection of the bat tick Carios fonsecai (Acari: Ixodidae with the rabies virus

    Directory of Open Access Journals (Sweden)

    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.

  8. Infectious Diseases in Wild Animals in Utah VI. Experimental Infection of Birds with Rickettsia rickettsii

    Science.gov (United States)

    Lundgren, D. L.; Thorpe, B. D.; Haskell, C. D.

    1966-01-01

    Lundgren, D. L. (University of Utah, Salt Lake City), B. D. Thorpe, and C. D. Haskell. Infectious diseases in wild animals in Utah. VI. Experimental infection of birds with Rickettsia rickettsii. J. Bacteriol. 91:963–966. 1966.—Chickens, pigeons, pheasants, sparrow hawks, red-tailed hawks, ravens, magpies, and a marsh hawk were inoculated with Rickettsia rickettsii, the etiological agent of Rocky Mountain spotted fever. The development and persistence of complement-fixing (CF) antibodies and rickettsemias were tested for in these birds. Rickettsiae were recovered from the blood of a number of birds up to the 16th day after inoculation, whereas only the pigeon was found to develop high CF antibody titers. It was concluded that certain species of birds have the potential of contributing to the dissemination of R. rickettsii in nature, and that the CF test is generally unsuitable for serological diagnosis of this organism in birds. PMID:4956338

  9. [Experimental infection of fattening swine with rotavirus: study of local immunity using coproantibodies].

    Science.gov (United States)

    Bernard, S; Groom, J; Lantier, I

    1984-01-01

    Fattened pigs were experimentally infected with porcine rotavirus (OSU strain). Viral antigens found in the faeces were analysed over a period of two months (ELISA method). We have found no correlation between virus excretion and the clinical manifestation of disease. The local immunity has been analysed in the faeces by the coproantibodies antirotavirus. The different classes of antibody, G, M, A and immune complexes have been determined using the ELISA method. The level of IgA antibodies was higher (10 fold) than IgG and IgM, and the timing of the appearance of these antibodies antivirus was also different. No correlation was found between local immunity and virus excretion in the faeces.

  10. Treatment of pigs experimentally infected with Mycoplasma hyopneumoniae, Pasteurella multocida, and Actinobacillus pleuropneumoniae with various antibiotics.

    Science.gov (United States)

    Stipkovits, L; Miller, D; Glavits, R; Fodor, L; Burch, D

    2001-10-01

    The authors have performed a comparative study of the efficacy of various in-feed medications for the treatment of 5- to 6-week-old specific pathogen-free (SPF) piglets experimentally infected on day 1 with Mycoplasma hyopneumoniae, on day 8 with Pasteurella multocida (serotype A), and on day 15 with Actinobacillus pleuropneumoniae (serotype 2). The treatment started on day 9 and continued for 12 consecutive days, then the piglets were euthanized for examination of macroscopic, histologic, and pathologic lesions and for the presence of mycoplasmas and bacteria in the lungs. Based on the results of clinical observations (respiratory signs, rectal temperature, body weight gain, and feed conversion efficiency), macroscopic and histologic lesions of the lungs, and microbiologic findings, the best results were obtained by treatment of pigs with Econor + chlortetracycline, followed by Tetramutin, Pulmotil, Cyfac, and lincomycin + chlortetracycline.

  11. Experimental Salmonella typhimurium infections in rats. III. Transfer of immunity with primed lymphocyte subpopulations

    DEFF Research Database (Denmark)

    Hougen, H P; Jensen, E T

    1990-01-01

    The protective effect of primed lymphocytes against a lethal dose of Salmonella typhimurium was studied in athymic and euthymic LEW rats. Primed lymphocytes were obtained by inoculating euthymic and thymus-grafted animals with a non-lethal dose of Salmonella typhimurium. Four weeks after...... as low as 10(4) cells from both euthymic or thymus-grafted animals were effective, and athymic and euthymic recipients survived equally well. Four weeks after the infection both athymic and euthymic animals housed very few bacteria and had high antibacterial antibody titres. The percentages of splenic...... and lymph node CD4+ cells in the athymic rats were comparable to those found in the euthymic animals. The study shows that primed CD4+ lymphocytes even in very low doses are able to induce immunity against a Salmonella typhimurium infection....

  12. Evaluation of the efficacy of a specific hyperimmune serum in experimental influenza infection in mice.

    Science.gov (United States)

    Marinescu, Bogdan; Coman, Cristin; Iancu, Adina Daniela; Stavaru, Crina; Lupulescu, Emilia; Onu, Adrian; Radu, Dorel Lucian

    2009-01-01

    Serotherapy still remains a way of treatment in some diseases, and it could be consider superior to any other mode of action because the protecting substances of the body are the products of the organism itself. The aim of the study was to establish an "in vivo" method for testing the efficacy of therapeutic serum. Hyperimmune serum for influenza A/PR8/34 viral strain, was prepared in sheep, and tested for inhibition of haemagglutination and microneutralisation. Seroprotection was evaluated in mice one day after being challenged with a lethal dose of the same virus. Our study shows that protection occurred in all mice treated with undiluted hyperimmune serum one day post infection (no clinical signs, faster recovery of the body weight after the first three days of the infection, all mice survived).

  13. Experimental caprine neosporosis: the influence of gestational stage on the outcome of infection.

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    Porto, Wagnner José Nascimento; Regidor-Cerrillo, Javier; Kim, Pomy de Cássia Peixoto; Benavides, Julio; Silva, Ana Clécia dos Santos; Horcajo, Pilar; Oliveira, Andrea Alice da Fonseca; Ferre, Ignacio; Mota, Rinaldo Aparecido; Ortega-Mora, Luis Miguel

    2016-02-11

    Here, we assessed outcome of experimental infection by Neospora caninum in goats intravenously inoculated with 10(6) tachyzoites of the Nc-Spain7 isolate at 40 (G1), 90 (G2) and 120 (G3) days of gestation. Infected goats had fever between 5 and 9 days post inoculation (dpi); all were seropositive at the time of abortion/birth. Foetal death occurred in G1 from 10 to 21 dpi (n = 7) and in G2 from 27 to 35 dpi (n = 4). Goats in G2 also had seropositive stillbirth (n = 1) and healthy kids (n = 2). G3 goats (n = 7) had 3 seropositive and 3 seronegative weak kids, and 2 seronegative healthy kids. Parasite DNA detection in placentomes was 100% in G2, 85.7% in G3 and in G1 was detected only in placentomes from the goats with foetal losses from 17 dpi (100%). Parasites were detected in foetal/kid brain (>85.7%) and liver (≥ 50%) of G2 and G3, and in G1 after 17 dpi (100%). The highest parasite loads were detected in the placentomes of G1 from 17 dpi and G2, and in foetal tissues of G1 from 17 dpi and G3. Multifocal necrotic lesions were observed in the placentas of the three groups, but they were larger and more frequent in G1 and G2. Similar lesions were observed in foetal tissues, but they were more frequent in G3. These findings suggest that, as observed in cattle and sheep, the clinical consequences of N. caninum in pregnant goats are dependent in part on the time of gestation when animals were infected.

  14. Human rhinovirus in experimental infection after peroral Lactobacillus rhamnosus GG consumption, a pilot study.

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    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 GG when compared to placebo. HRV load positively correlated with the total symptom scores. © 2016 ARS-AAOA, LLC.

  15. The efficacy of antihelminthic compound; Clorsulon against experimental Schistosoma mansoni infection.

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    Mossallam, Shereen F; Ali, Safia M; El Zawawy, Lobna A; Said, Doaa E

    2007-04-01

    The efficacy of Clorsulon (CLS) against experimental schistosomiasis mansoni, using Praziquantel (PZQ) as a therapeutic control was evaluated. Swiss Albino mice were divided into infected non-treated control, PZQ-treated group given a single dose of 500 mg/kg four weeks post infection (PI), and infected mice treated with single, double, and triple doses of 5 mg/kg CLS per dose, one week apart starting from the 4th week PI. All animals were perfused for adults count. Parts of livers and intestines were examined for granulomata number and sizes. Pathological changes in hepatic parenchyma by H&E and Masson trichrome stains were also examined. Results revealed that a single treatment with PZQ caused a significant percentage reduction (%R) of worm load (92.68%), mean egg count in liver and intestine (91.20 & 94.01% respectively), and mean size of liver granulomata was reduced (92.06%). Regarding CLS, the worm burden was reduced proportionally with number of doses given; 87.80, 96.34 & 97.56% in single, double and triple exposures successively. Egg count in liver was decreased by 85.90, 97.01 & 96.23% respectively in treated mice. Number of intestinal granulomata was decreased by 85.28, 94.24 & 95.49% in a similar way. Size of hepatic granulomata was decreased by 89.02, 94.51 & 95.05% by 1, 2 & 3 doses consecutively. All parameters reflected non significant difference between 2 & 3 dose of CLS. The results were critically discussed.

  16. An explorative study to assess the efficacy of Toltrazuril-sulfone (Ponazuril in calves experimentally infected with Neospora caninum

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    Greif Gisela

    2002-10-01

    Full Text Available Abstract Background Neospora caninum is an important cause of infectious abortion and stillbirth in cattle world-wide. Infection is common and may frequently be passed from mother to calf (vertical transmission with no signs of disease. Based on our previous observation that N. caninum-infection can be efficiently controlled with Toltrazuril-sulfone (Ponazuril in experimentally infected mice, we addressed the question if efficacy could also be obtained in experimentally infected calves. Material and Methods The study included 19 calves and represents an initial explorative approach to document a basic effectiveness at first. Fifteen animals received each 2 x 108N. caninum trophozoites, half of the dose being injected intravenously and the other half subcutaneously. Efficacy of treatment was assessed using molecular detection of parasite DNA with PCR and pathological alterations by immunohistochemistry in different organs of the animals. Assessment included also clinical, serological and pathophysiological parameters. Results In those calves medicated with ponazuril (one, or six consecutive days, respectively, starting one day after infection, a complete abrogation of the parasite detectability was obtained in the brain and other organs, while 50% of non-treated calves became PCR-positive in brain and muscles. Clinically, ponazuril chemotherapy of infected calves – in comparison to non-treated infected animals – reduced symptoms (fever, but no differences were observed between treated and non-treated animals with regard to serum enzymes and metabolites. Efficacy of a six-day treament was also reflected by significantly lower anti-Neospora antibody concentrations developed after infection, when compared to non-treated animals. Conclusion Based on our findings in this initially explorative approach that indicate a basic effectiveness of ponazuril against experimental N. caninum infection in calves, we plan to follow our chemotherapeutical

  17. An explorative study to assess the efficacy of toltrazuril-sulfone (ponazuril) in calves experimentally infected with Neospora caninum.

    Science.gov (United States)

    Kritzner, Sandra; Sager, Heinz; Blum, Jürg; Krebber, Ralph; Greif, Gisela; Gottstein, Bruno

    2002-10-18

    Neospora caninum is an important cause of infectious abortion and stillbirth in cattle world-wide. Infection is common and may frequently be passed from mother to calf (vertical transmission) with no signs of disease. Based on our previous observation that N. caninum-infection can be efficiently controlled with toltrazuril-sulfone (ponazuril) in experimentally infected mice, we addressed the question if efficacy could also be obtained in experimentally infected calves. The study included 19 calves and represents an initial explorative approach to document a basic effectiveness at first. Fifteen animals received each 2 x 10(8) N. caninum trophozoites, half of the dose being injected intravenously and the other half subcutaneously. Efficacy of treatment was assessed using molecular detection of parasite DNA with PCR and pathological alterations by immunohistochemistry in different organs of the animals. Assessment included also clinical, serological and pathophysiological parameters. In those calves medicated with ponazuril (one, or six consecutive days, respectively, starting one day after infection), a complete abrogation of the parasite detectability was obtained in the brain and other organs, while 50% of non-treated calves became PCR-positive in brain and muscles. Clinically, ponazuril chemotherapy of infected calves--in comparison to non-treated infected animals--reduced symptoms (fever), but no differences were observed between treated and non-treated animals with regard to serum enzymes and metabolites. Efficacy of a six-day treatment was also reflected by significantly lower anti-Neospora antibody concentrations developed after infection, when compared to non-treated animals. Based on our findings in this initially explorative approach that indicate a basic effectiveness of ponazuril against experimental N. caninum infection in calves, we plan to follow our chemotherapeutical intervention strategy to control bovine neosporosis with a subsequent more

  18. 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 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 (Pmastitis than in others which did not (0.709 and 0.162 versus 0.662 and 0.136, respectively; Pmastitis (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; Pmastitis. 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.

  19. Experimental Oral Herpes Simplex Virus-1 (HSV-1 Co-infection in Simian Immunodeficiency Virus (SIV-Infected Rhesus Macaques

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    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.

  20. 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.

  1. [Prevention of surgical infection using reabsorbable antibacterial suture (Vicryl Plus) versus reabsorbable conventional suture in hernioplasty. An experimental study in animals].

    Science.gov (United States)

    Suárez Grau, Juan Manuel; De Toro Crespo, María; Docobo Durántez, Fernando; Rubio Chaves, Carolina; Martín Cartes, Juan Antonio; Docobo Pérez, Fernando

    2007-06-01

    Surgical site infections are frequent in daily surgical practice. One of the main challenges currently facing surgeons is the prevention and treatment of infections, especially those involving prosthetic material. A new suture (Vicryl Plus) has become available. In vitro studies and experimental models have demonstrated the ability of this suture to inhibit bacterial growth and consequently prevent postsurgical infection. To compare infections provoked in prosthetic implants fixed with reabsorbable conventional sutures with those in meshes fixed with reabsorbable sutures with antiseptic impregnation. Twenty white Wistar rats were used. In each rat, two hernioplasties were performed: one fixed with Vicryl Plus and the other with normal Vicryl. Subsequently, each polypropylene mesh was infected with S. aureus, and the rats remained in individual cages for a week. After 1 week, the rats were sacrificed and the meshes were extracted for macroscopic, microscopic and microbiologic study. Most of the meshes fixed with the new suture (Vicryl Plus) showed macroscopically fewer infections than those fixed with conventional suture, without abscesses and without dehiscence of the hernioplasty. In the microbiological quantitative bacterial study, the number of bacteria quantified per gram of sample was also lower in prostheses fixed with Vicryl Plus. Pathological analysis showed lesser colonization of the mesh and lower inflammatory response with Vicryl Plus than with normal Vicryl. In the statistical analysis, comparison of the medians of both groups and the interquartile ranges of microbial quantification revealed a lower infection rate in the Vicryl Plus group. The infection rate in the surgical site can be reduced by mesh fixation using the new antimicrobial suture (Vicryl Plus). We believe that this type of suture constitutes a new weapon in the fight against postoperative infection, especially in hernioplasty, emergency surgery, and dirty or potentially contaminated

  2. 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.

  3. 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

  4. Experimental infection in cattle: kinetics of production of IgM and IgG against bovine cysticercosis and inflammatory response

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    Rafaella Paola Meneguete dos Guimarães-Peixoto

    2015-04-01

    Full Text Available Bovine cysticercosis is a zoonosis that affects humans in their adult form (taeniasis and its larval is found inserted in the musculature of infected cattle (cysticerci. It is still not entirely clear how animal immune response against infection occurs, being the comprehension of this process necessary for the enhancement of diagnostic capacity and disease prevention. This work aimed to evaluate the evolution of the immune response in experimentally infected cattle, compared with findings in cell response by optical microscopy. Nine animals were infected at a rate of 120,000 eggs of Taenia saginata. Five of the animals were similar in the kinetics of antibody production against cysticerci, with maximal levels of IgG and IgM. The other four animals showed an immune response different from the majority, with two of them showing delayed response to infection by cysticerci while the others apparently did not have initial contact with antigens secreted by cysticerci. Regarding the cellular response, it was found that, in lesions of viable cysticerci, inflammatory cells predominated, whereas in nonviable cysticerci there were tissue repair cells in the most part, being possible to notice that the amount of migratory calcareous corpuscles are related to the death stage of the parasite. These findings are important for the understanding immune response of cattle infected with cysticercosis.

  5. The effects of experimentally infecting Australian tree frogs with lungworms (Rhabdias pseudosphaerocephala) from invasive cane toads.

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    Pizzatto, Lígia; Shine, Richard

    2011-08-01

    Invasive species may transmit novel pathogens to native taxa, and lacking a history of coevolutionary interactions with the pathogen, the new hosts may be severely affected. Cane toads (Rhinella marina) were introduced to Australia in 1935, bringing with them a lungworm (Rhabdias pseudosphaerocephala) not found in Australian frogs. Previous studies suggest that most frog species are unaffected by this parasite, but one tree-frog (Litoria caerulea) can harbour high numbers of lungworm. More detailed laboratory studies confirm and extend the earlier results on L. caerulea and show that Rhabdias infection severely depresses the viability of metamorphs of an allied tree-frog species, Litoria splendida. Parasitic larvae infected both of these two closely related tree-frog species, but the two anurans differed in the consequences of infection. Parasitism reduced the survivorship of L. splendida and the stamina of both species. Lungworms did not consistently reduce growth rates or affect heart rates in either tree-frog species. Although L. splendida is potentially vulnerable to the arrival of toad-transported lungworms, rates of host-switching may be reduced by low levels of habitat overlap between the frogs (which are rock-dwelling and arboreal) and the toads (which are terrestrial and most abundant in disturbed habitats). Copyright © 2011 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

  6. Observations on Arthritis in Broiler Breeder Chickens Experimentally Infected with Staphylococcus aureus

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    Chang-Qin Gu§, Xue-Ying Hu§, Chang-Qing Xie1, Wan-Po Zhang, De-Hai Wang, Quan Zhou and Guo-Fu Cheng1*

    2013-04-01

    Full Text Available Staphylococcus aureus is the most common cause of bacterial arthritis in broiler breeder chickens. In this study, we established a model of broiler breeder chicken arthritis inoculated with Staph. aureus isolated from a spontaneously occurring bacterial arthritis in chickens. We evaluated the model by bacteriology, serology, pathology, and immunology. The results showed that 2.5 × 109 cfu Staph. aureus injected into the right joint cavity can successfully induce a chicken arthritis model. The majority of the infected chickens suffered lameness and joint swelling at 3 days post-inoculation (DPI. The death peak time was on 7 DPI and the mortality rate was 51.1%. Staph. aureus can be continuously isolated from the blood and left joint synovial fluid of the infected chickens. Lesions found on the infected chickens consisted of swollen joints full of caseous exudates, cartilage injury, and synovial membrane thickening with infiltration of inflammatory cells. The center of the lesion contained many round bacterial cocci. With joint injury aggravation, intra-articular hyaluronic acid gradually decreased, and serum interleukin-6 became significantly higher compared with the control (P<0.01 from 3 DPI. The results indicated that the chicken models of Staph. aureus-mediated arthritis were successful, and can be used to gain a better understanding of the host-bacterium relationship.

  7. Therapeutic Effects of Allium sativum and Allium cepa in Schistosoma mansoni experimental infection

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    Mona Mohamed Mantawy

    2011-06-01

    Full Text Available The effects of both garlic (Allium sativum and onion (Allium cepa on some biochemical parameters in Schistosoma mansoni infected mice individually and mixed either with or without the currently used drug, praziquantel (PZQ were investigated. These involved some immunological parameters, namely IgM, IgG, interleukins 2 and 6 (IL-2 and 6 and tumor necrosis factor (TNF-α, some antioxidant enzymes [catalase, superoxide dismutase (SOD and glutathione peroxidase (GPX]. In addition, parasitological and histopathological investigations were performed. No changes were observed in the normal control mice treated with dry extract of onion or garlic, individually or mixed, with or without PZQ, compared to the normal healthy control group. Infection with S. mansoni showed an increase in IgG, IgM, IL-2, IL-6, TNF-α and catalase enzyme, accompanied with a decrease in GPX and SOD antioxidant enzyme activities. Remarkable amelioration was noticed in the levels of all the measured parameters in S. mansoni infected mice after administration of the studied extracts. Moreover a significant reduction in worm burden, hepatic and intestinal eggs and oogram count was noticed which was reflected in normalization of liver architecture.

  8. Genome wide host gene expression analysis in mice experimentally infected with Pasteurella multocida.

    Science.gov (United States)

    Priya, G Bhuvana; Nagaleekar, Viswas Konasagara; Milton, A Arun Prince; Saminathan, M; Kumar, Amod; Sahoo, Amit Ranjan; Wani, Sajad Ahmad; Kumar, Amit; Gupta, S K; Sahoo, Aditya P; Tiwari, A K; Agarwal, R K; Gandham, Ravi Kumar

    2017-01-01

    Pasteurella multocida causes acute septicemic and respiratory diseases, including haemorrhagic septicaemia, in cattle and buffalo with case fatality of 100%. In the present study, mice were infected with P. multocida (1.6 × 103 cfu, intraperitoneal) to evaluate host gene expression profile at early and late stages of infection using high throughput microarray transcriptome analyses. Several differentially expressed genes (DEGs) at both the time points were identified in P.multocida infected spleen, liver and lungs. Functional annotation of these DEGs showed enrichment of key pathways such as TLR, NF-κB, MAPK, TNF, JAK-STAT and NOD like receptor signaling pathways. Several DEGs overlapped across different KEGG pathways indicating a crosstalk between them. The predicted protein-protein interaction among these DEGs suggested, that the recognition of P. multocida LPS or outer membrane components by TLR4 and CD14, results in intracellular signaling via MyD88, IRAKs and/or TRAF6 leading to activation of NFκB and MAPK pathways and associated cytokines.

  9. Effect of Eimeria adenoeides Challenge upon the Course of an Experimental Salmonella Enteritidis Infection in Turkey Poults

    OpenAIRE

    KOINARSKI, Ventsislav; LYUTSKANOV, Mihni; URUMOVA, Valentina

    2006-01-01

    The aim of the present study was to perform a controlled experiment in order to evaluate the predisposing role of Eimeria adenoeides invasion on the appearance, development and severity of a Salmonella Enteritidis infection, with both infectious agents being field isolates obtained from spontaneous cases of the disease. Furthermore, we aimed to examine the principal epidemiological parameters of the mixed infection. The effect of an experimental Eimeria adenoeides invasion upon an artificial...

  10. Transcriptional Profiling of Hilar Nodes from Pigs after Experimental Infection with Actinobacillus Pleuropneumoniae

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    Shumin Yu

    2013-11-01

    Full Text Available The gram-negative bacterium Actinobacillus pleuropneumoniae (APP is an inhabitant of the porcine upper respiratory tract and the causative agent of porcine pleuropneumonia (PP. In recent years, knowledge about the proinflammatory cytokine and chemokine gene expression that occurs in lung and lymph node of the APP-infected swine has been advanced. However, systematic gene expression profiles on hilar nodes from pigs after infection with Actinobacillus pleuropneumoniae have not yet been reported. The transcriptional responses were studied in hilar nodes (HN from swine experimentally infected with APP and the control groupusing Agilent Porcine Genechip, including 43,603 probe sets. 9,517 transcripts were identified as differentially expressed (DE at the p ≤ 0.01 level by comparing the log2 (normalized signal of the two groups named treatment group (TG and controls (CG. Eight hundred and fifteen of these DE transcripts were annotated as pig genes in the GenBank database (DB. Two hundred and seventy-two biological process categories (BP, 75 cellular components and 171 molecular functions were substantially altered in the TG compared to CG. Many BP were involved in host immune responses (i.e., signaling, signal transmission, signal transduction, response to stimulus, oxidation reduction, response to stress, immune system process, signaling pathway, immune response, cell surface receptor linked signaling pathway. Seven DE gene pathways (VEGF signaling pathway, Long-term potentiation, Ribosome, Asthma, Allograft rejection, Type I diabetes mellitus and Cardiac muscle contraction and statistically significant associations with host responses were affected. Many cytokines (including NRAS, PI3K, MAPK14, CaM, HSP27, protein phosphatase 3, catalytic subunit and alpha isoform, mediating the proliferation and migration of endothelial cells and promoting survival and vascular permeability, were activated in TG, whilst many immunomodulatory cytokines were

  11. An experimental approach to the immuno-modulatory basis of host-parasite local adaptation in tapeworm-infected sticklebacks.

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    Hamley, Madeleine; Franke, Frederik; Kurtz, Joachim; Scharsack, Jörn Peter

    2017-09-01

    The evolutionary arms race of hosts and parasites often results in adaptations, which may differ between populations. Investigation of such local adaptation becomes increasingly important to understand dynamics of host-parasite interactions and co-evolution. To this end we performed an infection experiment involving pairs of three-spined sticklebacks and their tapeworm parasite Schistocephalus solidus from three geographically separated origins (Germany, Spain and Iceland) in a fully-crossed design for sympatric and allopatric host/parasite combinations. We hypothesized that local adaptation of the hosts results in differences in parasite resistance with variation in parasite infection rates and leukocyte activation, whereas parasites from different origins might differ in virulence reflected in host exploitation rates (parasite indices) and S. solidus excretory-secretory products (SsESP) involved in immune manipulation. In our experimental infections, sticklebacks from Iceland were more resistant to S. solidus infection compared to Spanish and German sticklebacks. Higher resistance of Icelandic sticklebacks seemed to depend on adaptive immunity, whereas sticklebacks of German origin, which were more heavily afflicted by S. solidus, showed elevated activity of innate immune traits. German S. solidus were less successful in infecting and exploiting allopatric hosts compared to their Icelandic and Spanish conspecifics. Nevertheless, exclusively SsESP from German S. solidus triggered significant in vitro responses of leukocytes from naïve sticklebacks. Interestingly, parasite indices were almost identical across the sympatric combinations. Differences in host resistance and parasite virulence between the origins were most evident in allopatric combinations and were consistent within origin; i.e. Icelandic sticklebacks were more resistant and their S. solidus were more virulent in all allopatric combinations, whereas German sticklebacks were less resistant and

  12. Efficacy of extended pirlimycin therapy for treatment of experimentally induced Streptococcus uberis intramammary infections in lactating dairy cattle.

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    Oliver, Stephen P; Almeida, Raul A; Gillespie, Barbara E; Ivey, Susan J; Moorehead, Hugh; Lunn, Phillip; Dowlen, Henry H; Johnson, David L; Lamar, Ken C

    2003-01-01

    Streptococcus uberis is an important cause of mastitis in dairy cows throughout the world, particularly during the dry period, around the time of calving, and during early lactation. Strategies for controlling S. uberis mastitis have not received adequate research attention and are therefore poorly defined and inadequate. Objectives of the present study were to evaluate the efficacy of extended therapy regimens with pirlimycin for treatment of experimentally induced S. uberis intramammary infections in lactating dairy cows during early lactation and to evaluate the usefulness of the S. uberis experimental infection model for evaluating antimicrobial efficacy in dairy cows. The efficacy of extended pirlimycin intramammary therapy regimens was investigated in 103 mammary glands of 68 dairy cows that became infected following experimental challenge with S. uberis during early lactation. Cows infected with S. uberis in one or both experimentally challenged mammary glands were randomly allocated to three groups, representing three different treatment regimens with pirlimycin, including 2-day (n = 21 cows, 31 mammary quarters), 5-day (n = 21 cows, 32 quarters), and 8-day (n = 26 cows, 40 quarters). For all groups, pirlimycin was administered at a rate of 50 mg of pirlimycin hydrochloride via intramammary infusion. A cure was defined as an experimentally infected mammary gland that was treated with pirlimycin and was bacteriologically negative for the presence of S. uberis at 7, 14, 21, and 28 days after treatment. Experimental S. uberis intramammary infections were eliminated in 58.1% of the infected quarters treated with the pirlimycin 2-day regimen, 68.8% for the 5-day regimen, and 80.0% for the 8-day regimen. Significant differences (P <.05) in efficacy were observed between the 2-day and 8-day treatment regimens. The number of somatic cells in milk decreased significantly following therapy in quarters for which treatment was successful in eliminating S. uberis

  13. Respiratory syncytial virus human experimental infection model: provenance, production, and sequence of low-passaged memphis-37 challenge virus.

    Directory of Open Access Journals (Sweden)

    Young-In Kim

    Full Text Available Respiratory syncytial virus (RSV is the leading cause of lower respiratory tract infections in children and is responsible for as many as 199,000 childhood deaths annually worldwide. To support the development of viral therapeutics and vaccines for RSV, a human adult experimental infection model has been established. In this report, we describe the provenance and sequence of RSV Memphis-37, the low-passage clinical isolate used for the model's reproducible, safe, experimental infections of healthy, adult volunteers. The predicted amino acid sequences for major proteins of Memphis-37 are compared to nine other RSV A and B amino acid sequences to examine sites of vaccine, therapeutic, and pathophysiologic interest. Human T- cell epitope sequences previously defined by in vitro studies were observed to be closely matched between Memphis-37 and the laboratory strain RSV A2. Memphis-37 sequences provide baseline data with which to assess: (i virus heterogeneity that may be evident following virus infection/transmission, (ii the efficacy of candidate RSV vaccines and therapeutics in the experimental infection model, and (iii the potential emergence of escape mutants as a consequence of experimental drug treatments. Memphis-37 is a valuable tool for pre-clinical research, and to expedite the clinical development of vaccines, therapeutic immunomodulatory agents, and other antiviral drug strategies for the protection of vulnerable populations against RSV disease.

  14. Respiratory syncytial virus human experimental infection model: provenance, production, and sequence of low-passaged memphis-37 challenge virus.

    Science.gov (United States)

    Kim, Young-In; DeVincenzo, John P; Jones, Bart G; Rudraraju, Rajeev; Harrison, Lisa; Meyers, Rachel; Cehelsky, Jeff; Alvarez, Rene; Hurwitz, Julia L

    2014-01-01

    Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract infections in children and is responsible for as many as 199,000 childhood deaths annually worldwide. To support the development of viral therapeutics and vaccines for RSV, a human adult experimental infection model has been established. In this report, we describe the provenance and sequence of RSV Memphis-37, the low-passage clinical isolate used for the model's reproducible, safe, experimental infections of healthy, adult volunteers. The predicted amino acid sequences for major proteins of Memphis-37 are compared to nine other RSV A and B amino acid sequences to examine sites of vaccine, therapeutic, and pathophysiologic interest. Human T- cell epitope sequences previously defined by in vitro studies were observed to be closely matched between Memphis-37 and the laboratory strain RSV A2. Memphis-37 sequences provide baseline data with which to assess: (i) virus heterogeneity that may be evident following virus infection/transmission, (ii) the efficacy of candidate RSV vaccines and therapeutics in the experimental infection model, and (iii) the potential emergence of escape mutants as a consequence of experimental drug treatments. Memphis-37 is a valuable tool for pre-clinical research, and to expedite the clinical development of vaccines, therapeutic immunomodulatory agents, and other antiviral drug strategies for the protection of vulnerable populations against RSV disease.

  15. Emergence of quinolone-resistant, topoisomerase-mutant Brucella after treatment with fluoroquinolones in a macrophage