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Sample records for agent coxiella burnetii

  1. Coxiella burnetii Genotyping

    PubMed Central

    Glazunova, Olga; Roux, Véronique; Freylikman, Olga; Sekeyova, Zuzana; Fournous, Ghislain; Tyczka, Judith; Tokarevich, Nikolai; Kovacova, Elena; Marrie, Thomas J.

    2005-01-01

    Coxiella burnetii is a strict intracellular bacterium with potential as a bioterrorism agent. To characterize different isolates of C. burnetii at the molecular level, we performed multispacer sequence typing (MST). MST is based on intergenic region sequencing. These regions are potentially variable since they are subject to lower selection pressure than the adjacent genes. We screened 68 spacers in 14 isolates and selected the 10 that exhibited the most variation. These spacers were then tested in 159 additional isolates obtained from different geographic areas or different hosts or were implicated in different manifestations of human disease caused by C. burnetii. The sequence analysis yielded 30 different allelic combinations. Phylogenic analysis showed 3 major clusters. MST allows easy comparison and exchange of results obtained in different laboratories and could be a useful tool for identifying bacterial strains. PMID:16102309

  2. Coxiella burnetii, the agent of Q fever, in domestic sheep flocks from Wyoming, United States.

    PubMed

    Loftis, Amanda D; Reeves, Will K; Miller, Myrna M; Massung, Robert F

    2012-03-01

    Coxiella burnetii, the agent of Q fever, is an intracellular bacterial pathogen. It has a nearly cosmopolitan distribution. We conducted a serological survey of domestic sheep herds for infections with C. burnetii in Wyoming following reports of abortion and open ewes. Based on the serologic evidence, there was no link between reproductive problems and exposure to C. burnetii. However, the overall prevalence of C. burnetii in WY sheep was 7%, which indicates that the agent is present in the environment and could pose a threat to public health.

  3. Persistence of Coxiella burnetii, the Agent of Q Fever, in Murine Adipose Tissue

    PubMed Central

    Bechah, Yassina; Verneau, Johanna; Ben Amara, Amira; Barry, Abdoulaye O.; Lépolard, Catherine; Achard, Vincent; Panicot-Dubois, Laurence; Textoris, Julien; Capo, Christian; Ghigo, Eric; Mege, Jean-Louis

    2014-01-01

    Coxiella burnetii, the agent of Q fever, is known to persist in humans and rodents but its cellular reservoir in hosts remains undetermined. We hypothesized that adipose tissue serves as a C. burnetii reservoir during bacterial latency. BALB/c and C57BL/6 mice were infected with C. burnetii by the intraperitoneal route or the intracheal route. Adipose tissue was tested for the presence of C. burnetii several months after infection. C. burnetii was detected in abdominal, inguinal and dorsal adipose tissue 4 months post-infection, when no bacteria were detected in blood, liver, lungs and spleen, regardless of the inoculation route and independently of mouse strain. The transfer of abdominal adipose tissue from convalescent BALB/c mice to naïve immunodeficient mice resulted in the infection of the recipient animals. It is likely that C. burnetii infects adipocytes in vivo because bacteria were found in adipocytes within adipose tissue and replicated within in vitro-differentiated adipocytes. In addition, C. burnetii induced a specific transcriptional program in in-vivo and in vitro-differentiated adipocytes, which was enriched in categories associated with inflammatory response, hormone response and cytoskeleton. These changes may account for bacterial replication in in-vitro and chronic infection in-vivo. Adipose tissue may be the reservoir in which C. burnetii persists for prolonged periods after apparent clinical cure. The mouse model of C. burnetii infection may be used to understand the relapses of Q fever and provide new perspectives to the follow-up of patients. PMID:24835240

  4. DNA microarray-based detection of Coxiella burnetii, the causative agent of Q fever

    PubMed Central

    2014-01-01

    Background An easy-to-handle microarray assay based on the cost-effective ArrayTube™ platform has been designed for the rapid and unequivocal identification of Coxiella burnetii, the causative agent of Q fever. The gene targets include the chromosomally coded markers icd, omp/com1, and IS1111 as well as the plasmid coded markers cbbE and cbhE. Results A representative panel comprising 50 German C. burnetii isolates and 10 clinical samples was examined to validate the test. All tested isolates harboured plasmid QpH1 and were correctly identified, corresponding to 100% sensitivity. The assay’s limit of detection was 100 genome equivalents (GE) for icd, omp/com1, cbbE and cbhE and 10 GE for IS1111. Assay specificity was 100% as determined by analysing a panel of 37 non-Coxiella strains. Conclusions The present array is a rational assembly of established and evaluated targets for the rapid and unequivocal detection of C. burnetii. This array could be applied to the screening of vaginal swabs from small ruminants; screening of environmental samples e.g. on farms or screening of human samples. PMID:24886299

  5. The survival of Coxiella burnetii in soils

    NASA Astrophysics Data System (ADS)

    Evstigneeva, A. S.; Ul'Yanova, T. Yu.; Tarasevich, I. V.

    2007-05-01

    Coxiella burnetii is a pathogen of Q-fever—a widespread zoonosis. The effective adaptation of C. burnetii to intracellular existence is in contrast with its ability to survive in the environment outside the host cells and its resistance to chemical and physical agents. Its mechanism of survival remains unknown. However, its survival appears to be related to the developmental cycle of the microorganism itself, i.e., to the formation of its dormant forms. The survival of Coxiella burnetii was studied for the first time. The pathogenic microorganism was inoculated into different types of soil and cultivated under different temperatures. The survival of the pathogen was verified using a model with laboratory animals (mice). Viable C. burnetii were found in the soil even 20 days after their inoculation. The relationship between the organic carbon content in the soils and the survival of C. burnetii was revealed. Thus, the results obtained were the first to demonstrate that the soil may serve as a reservoir for the preservation and further spreading of the Q-fever pathogen in the environment, on the one hand, and reduce the risk of epidemics, on the other.

  6. First molecular evidence of Coxiella burnetii infecting ticks in Cuba.

    PubMed

    Noda, Angel A; Rodríguez, Islay; Miranda, Jorge; Contreras, Verónica; Mattar, Salim

    2016-02-01

    Coxiella burnetii is the causative agent of Q fever. In order to explore the occurrence of C. burnetii in ticks, samples were collected from horses, dogs and humans living in a Cuban occidental community. The species most commonly recovered were Amblyomma mixtum (67%), Rhipicephalus sanguineus s.l. (27%) and Dermacentor nitens (6%). Specific IS1111 PCR and amplicon sequencing allowed the identification of C. burnetii DNA in A. mixtum collected from a domestic horse. These findings, for first time in Cuba, indicate the need for an in-depth assessment of the C. burnetii occurrence in hosts and humans at risk of infection.

  7. European Rabbits as Reservoir for Coxiella burnetii.

    PubMed

    González-Barrio, David; Maio, Elisa; Vieira-Pinto, Madalena; Ruiz-Fons, Francisco

    2015-06-01

    We studied the role of European rabbits (Oryctolagus cuniculus) as a reservoir for Coxiella burnetii in the Iberian region. High individual and population seroprevalences observed in wild and farmed rabbits, evidence of systemic infections, and vaginal shedding support the reservoir role of the European rabbit for C. burnetii.

  8. European Rabbits as Reservoir for Coxiella burnetii.

    PubMed

    González-Barrio, David; Maio, Elisa; Vieira-Pinto, Madalena; Ruiz-Fons, Francisco

    2015-06-01

    We studied the role of European rabbits (Oryctolagus cuniculus) as a reservoir for Coxiella burnetii in the Iberian region. High individual and population seroprevalences observed in wild and farmed rabbits, evidence of systemic infections, and vaginal shedding support the reservoir role of the European rabbit for C. burnetii. PMID:25988670

  9. Coxiella burnetii Shedding by Farmed Red Deer (Cervus elaphus).

    PubMed

    González-Barrio, D; Almería, S; Caro, M R; Salinas, J; Ortiz, J A; Gortázar, C; Ruiz-Fons, F

    2015-10-01

    Wildlife and notably deer species--due to the increasing relevance of deer farming worldwide--may contribute to the maintenance of Coxiella burnetii, the causal agent of Q fever. Currently, there are no precedents linking exposure to deer species with human Q fever cases. However, a human case of Q fever was recently diagnosed in a red deer (Cervus elaphus) farm, which led us to investigate whether deer could be a source for environmental contamination with C. burnetii and ascertain the implication of C. burnetii in reproductive failure in the farm. Blood serum and vaginal swabs were collected from hinds either experiencing or not reproductive failure and tested to detect the presence of antibodies and DNA, respectively, of C. burnetii, Chlamydia abortus, Neospora caninum and Toxoplasma gondii. Serology and PCR results suggest C. burnetii was the primary cause of the reproductive failure. We identified vaginal shedding of C. burnetii in hinds, confirming red deer as a source of Q fever zoonotic infection.

  10. Coxiella burnetii in wild-caught filth flies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Coxiella burnetii, the agent of Q fever, is a pathogen of vertebrates. In domestic animals, Q fever can cause abortion and reduced fertility. Infections in humans can be debilitating but are rarely fatal. House flies are vectors of Q fever in the laboratory, but infections in field caught flies have...

  11. Sec-mediated secretion by Coxiella burnetii

    PubMed Central

    2013-01-01

    Background Coxiella burnetii is a Gram-negative intracellular bacterial pathogen that replicates within a phagolysosome-like parasitophorous vacuole (PV) of macrophages. PV formation requires delivery of effector proteins directly into the host cell cytoplasm by a type IVB secretion system. However, additional secretion systems are likely responsible for modification of the PV lumen microenvironment that promote pathogen replication. Results To assess the potential of C. burnetii to secrete proteins into the PV, we analyzed the protein content of modified acidified citrate cysteine medium for the presence of C. burnetii proteins following axenic (host cell-free) growth. Mass spectrometry generated a list of 105 C. burnetii proteins that could be secreted. Based on bioinformatic analysis, 55 proteins were selected for further study by expressing them in C. burnetii with a C-terminal 3xFLAG-tag. Secretion of 27 proteins by C. burnetii transformants was confirmed by immunoblotting culture supernatants. Tagged proteins expressed by C. burnetii transformants were also found in the soluble fraction of infected Vero cells, indicating secretion occurs ex vivo. All secreted proteins contained a signal sequence, and deletion of this sequence from selected proteins abolished secretion. These data indicate protein secretion initially requires translocation across the inner-membrane into the periplasm via the activity of the Sec translocase. Conclusions C. burnetii secretes multiple proteins, in vitro and ex vivo, in a Sec-dependent manner. Possible roles for secreted proteins and secretion mechanisms are discussed. PMID:24093460

  12. Mouse Model of Coxiella burnetii Aerosolization.

    PubMed

    Melenotte, Cléa; Lepidi, Hubert; Nappez, Claude; Bechah, Yassina; Audoly, Gilles; Terras, Jérôme; Raoult, Didier; Brégeon, Fabienne

    2016-07-01

    Coxiella burnetii is mainly transmitted by aerosols and is responsible for multiple-organ lesions. Animal models have shown C. burnetii pathogenicity, but long-term outcomes still need to be clarified. We used a whole-body aerosol inhalation exposure system to mimic the natural route of infection in immunocompetent (BALB/c) and severe combined immunodeficient (SCID) mice. After an initial lung inoculum of 10(4) C. burnetii cells/lung, the outcome, serological response, hematological disorders, and deep organ lesions were described up to 3 months postinfection. C. burnetii-specific PCR, anti-C. burnetii immunohistochemistry, and fluorescent in situ hybridization (FISH) targeting C. burnetii-specific 16S rRNA completed the detection of the bacterium in the tissues. In BALB/c mice, a thrombocytopenia and lymphopenia were first observed, prior to evidence of C. burnetii replication. In all SCID mouse organs, DNA copies increased to higher levels over time than in BALB/c ones. Clinical signs of discomfort appeared in SCID mice, so follow-up had to be shortened to 2 months in this group. At this stage, all animals presented bone, cervical, and heart lesions. The presence of C. burnetii could be attested in situ for all organs sampled using immunohistochemistry and FISH. This mouse model described C. burnetii Nine Mile strain spread using aerosolization in a way that corroborates the pathogenicity of Q fever described in humans and completes previously published data in mouse models. C. burnetii infection occurring after aerosolization in mice thus seems to be a useful tool to compare the pathogenicity of different strains of C. burnetii. PMID:27160294

  13. High seroprevalence of Coxiella burnetii in dairy cattle in China.

    PubMed

    El-Mahallawy, Heba S; Kelly, Patrick; Zhang, Jilei; Yang, Yi; Zhang, Hui; Wei, Lanjing; Mao, Yongjiang; Yang, Zhangping; Zhang, Zhenwen; Fan, Weixing; Wang, Chengming

    2016-02-01

    Coxiella burnetii is the agent of Q fever, a zoonosis which occurs worldwide. As there is little reliable data on the organism in China, we investigated C. burnetii infections in dairy cattle herds around the country. Opportunistic whole blood samples were collected from 1140 dairy cattle in 19 herds, and antibodies to phase I and II C. burnetii antigens were detected using commercial ELISA kits. Seropositive cattle (381/1140, 33 %) were detected in 13 of the 15 surveyed provinces and in 16 of the 19 herds (84 %) studied. Our data indicates C. burnetii is widespread in China and that animal and human health workers should be aware of the possibility of Q fever infection in their patients.

  14. Proteomic comparison of phase I and II coxiella burnetii cells reveals potential virulence biomarkers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Coxiella burnetii, a category B biological warfare agent, causes several worldwide outbreaks of zoonotic disease each year. In order to identify C. burnetii virulence factors, the virulent phase I and avirulent phase II variants of the Nine Mile RSA strains, were propagated in embryonated hen eggs ...

  15. Coxiella burnetii in central Italy: novel genotypes are circulating in cattle and goats.

    PubMed

    Di Domenico, Marco; Curini, Valentina; De Massis, Fabrizio; Di Provvido, Andrea; Scacchia, Massimo; Cammà, Cesare

    2014-10-01

    Genotyping of bacteria is critical for diagnosis, treatment, and epidemiological surveillance. Coxiella burnetii, the etiological agent of Q fever, has been recognized to have a potential for bioterrorism purposes. Because few serosurveys have been conducted in Italy, there is still limited information about the distribution of this pathogen in natural conditions. In this paper, we describe the genotyping of C. burnetii strains by multispacer sequence typing (MST) detected in cattle and goat farms in the Abruzzi region of Italy. Biological samples (milk, aborted fetus) positive for C. burnetii DNA were sequenced in the spacer regions and compared with those already publicly available ( http://ifr48.timone.univ-mrs.fr/MST_Coxiella/mst/group_detail ). The MST profile of C. burnetii detected in milk samples demonstrated the presence of a new allele, whereas the C. burnetii spacer sequences from fetus and milk goat samples displayed a new allelic combination. The results suggest the circulation of novel genotypes of C. burnetii in Italy.

  16. Loss of TSS1 in hypervirulent Coxiella burnetii 175, the causative agent of Q fever in French Guiana.

    PubMed

    D'Amato, Felicetta; Eldin, Carole; Georgiades, Kalliopi; Edouard, Sophie; Delerce, Jeremy; Labas, Noémie; Raoult, Didier

    2015-08-01

    In French Guiana, the unique Coxiella burnetii circulating genotype 17 causes 24% of community-acquired pneumonia, the highest prevalence ever described. To explain this unusual virulence, we performed a comparative genomic analysis of strain Cb175, which was isolated from a patient from French Guiana. Cb175 has a greater number of mutations in genes involved in metabolism compared with the Nine Mile I strain. We found a 6105bp fragment missing in Cb175, which corresponds to the Type 1 secretion systems (T1SS) hlyCABD operon region. This deletion was detected by a specific qPCR in the 8 other strains available from this territory an in none of 298C.burnetii strains from other areas and other genotypes (8/8 vs 0/298, Fisher's exact test, p<0.0000001). Loss of genes implicated in secretion systems has been observed in other epidemic bacterial strains. Thus, the virulence of Cb175 may be linked to this genome reduction. PMID:25982513

  17. Loss of TSS1 in hypervirulent Coxiella burnetii 175, the causative agent of Q fever in French Guiana.

    PubMed

    D'Amato, Felicetta; Eldin, Carole; Georgiades, Kalliopi; Edouard, Sophie; Delerce, Jeremy; Labas, Noémie; Raoult, Didier

    2015-08-01

    In French Guiana, the unique Coxiella burnetii circulating genotype 17 causes 24% of community-acquired pneumonia, the highest prevalence ever described. To explain this unusual virulence, we performed a comparative genomic analysis of strain Cb175, which was isolated from a patient from French Guiana. Cb175 has a greater number of mutations in genes involved in metabolism compared with the Nine Mile I strain. We found a 6105bp fragment missing in Cb175, which corresponds to the Type 1 secretion systems (T1SS) hlyCABD operon region. This deletion was detected by a specific qPCR in the 8 other strains available from this territory an in none of 298C.burnetii strains from other areas and other genotypes (8/8 vs 0/298, Fisher's exact test, p<0.0000001). Loss of genes implicated in secretion systems has been observed in other epidemic bacterial strains. Thus, the virulence of Cb175 may be linked to this genome reduction.

  18. Virulent Coxiella burnetii pathotypes productively infect primary human alveolar macrophages.

    PubMed

    Graham, Joseph G; MacDonald, Laura J; Hussain, S Kauser; Sharma, Uma M; Kurten, Richard C; Voth, Daniel E

    2013-06-01

    The intracellular bacterial pathogen Coxiella burnetii is a category B select agent that causes human Q fever. In vivo, C. burnetii targets alveolar macrophages wherein the pathogen replicates in a lysosome-like parasitophorous vacuole (PV). In vitro, C. burnetii infects a variety of cultured cell lines that have collectively been used to model the pathogen's infectious cycle. However, differences in the cellular response to infection have been observed, and virulent C. burnetii isolate infection of host cells has not been well defined. Because alveolar macrophages are routinely implicated in disease, we established primary human alveolar macrophages (hAMs) as an in vitro model of C. burnetii-host cell interactions. C. burnetii pathotypes, including acute disease and endocarditis isolates, replicated in hAMs, albeit with unique PV properties. Each isolate replicated in large, typical PV and small, non-fused vacuoles, and lipid droplets were present in avirulent C. burnetii PV. Interestingly, a subset of small vacuoles harboured single organisms undergoing degradation. Prototypical PV formation and bacterial growth in hAMs required a functional type IV secretion system, indicating C. burnetii secretes effector proteins that control macrophage functions. Avirulent C. burnetii promoted sustained activation of Akt and Erk1/2 pro-survival kinases and short-termphosphorylation of stress-related p38. Avirulent organisms also triggered a robust, early pro-inflammatory response characterized by increased secretion of TNF-α and IL-6, while virulent isolates elicited substantially reduced secretion of these cytokines. A corresponding increase in pro- and mature IL-1β occurred in hAMs infected with avirulent C. burnetii, while little accumulation was observed following infection with virulent isolates. Finally, treatment of hAMs with IFN-γ controlled intracellular replication, supporting a role for this antibacterial insult in the host response to C. burnetii

  19. Seroprevalence of Coxiella burnetii in Australian dogs.

    PubMed

    Shapiro, A J; Norris, J M; Heller, J; Brown, G; Malik, R; Bosward, K L

    2016-09-01

    The role of dogs in the transmission of Coxiella burnetii to humans is uncertain, and extensive seroprevalence studies of dogs have not been previously conducted in Australia. This study determined C. burnetii exposure in four diverse canine subpopulations by adapting, verifying and comparing an indirect immunofluoresence assay (IFA) and an enzyme-linked immunosorbent assay (ELISA) used to detect anti-C. burnetii antibodies in humans. Canine serum samples (n = 1223) were tested with IFA from four subpopulations [breeding establishments; household pets; free-roaming dogs in Aboriginal communities; shelter dogs]. The proportions of seropositive dogs were as follows: breeding (7/309, 2.3%), household pets (10/328, 3%), Aboriginal communities (21/321, 6.5%) and shelters (5/265, 1.9%). Dogs from Aboriginal communities were 2.8 times (CI 1.5-5.1; P < 0.001) more likely to be seropositive than dogs from other populations. The ELISA was used on 86 of 1223 sera tested with IFA, and a Cohen's Kappa coefficient of 0.60 (CI 0.43-0.78) indicated good agreement between the two assays. This study has established that Australian dogs within all four subpopulations have been exposed to C. burnetii and that a higher seroprevalence was observed amongst free-roaming dogs associated with Aboriginal communities. As C. burnetii recrudesces during pregnancy and birth products contain the highest concentration of organism, individuals assisting at the time of parturition, those handling pups shortly after birth as well as those residing in the vicinity of whelping dogs are potentially at risk of developing Q fever. However, the identification of active antigen shed in excreta from seropositive dogs is required in order to accurately define and quantify the public health risk. PMID:26729351

  20. Diagnosis of Coxiella burnetii Infection: Comparison of a Whole Blood Interferon-Gamma Production Assay and a Coxiella ELISPOT

    PubMed Central

    Schoffelen, Teske; Limonard, Gijs J. M.; Bleeker-Rovers, Chantal P.; Bouwman, John J. M.; van der Meer, Jos W. M.; Nabuurs-Franssen, Marrigje; Sprong, Tom; van Deuren, Marcel

    2014-01-01

    Diagnosis of ongoing or past infection with Coxiella burnetii, the causative agent of Q fever, relies heavily on serology: the measurement of C. burnetii-specific antibodies, reflecting the host’s humoral immune response. However, cell-mediated immune responses play an important, probably even more relevant, role in infections caused by the intracellular C. burnetii bacterium. Recent studies have investigated interferon-gamma (IFN-γ) based assays, including a whole-blood IFN-γ production assay and a Coxiella enzyme-linked immunospot (Coxiella ELISPOT), as potential diagnostic tools for Q fever diagnosis. Both are in-house developed assays using stimulating antigens of different origin. The main objective of this study was to compare the test performance of the IFN-γ production assay and the Coxiella ELISPOT for detecting a cellular immune response to C. burnetii in Q fever patients, and to assess the correlation between both assays. To that end, both tests were performed in a well-defined patient group of chronic Q fever patients (n = 16) and a group of healthy seronegative individuals (n = 17). Among patients, both the Coxiella ELISPOT and the IFN-γ production assay detected positive response in 14/16. Among controls, none were positive in the Coxiella ELISPOT, whereas the IFN-γ production assay detected positive results in 1/17 and 3/17, when using Henzerling and Nine Mile as stimulating antigens, respectively. These results suggest the Coxiella ELISPOT has a somewhat higher specificity than the IFN-γ production assay when Nine Mile is used as antigen stimulus. The assays showed moderate correlation: the Spearman correlation coefficient r ranged between 0.37–0.60, depending on the antigens used. Further investigation of the diagnostic potential for C. burnetii infection of both assays is warranted. PMID:25084353

  1. Genome sequence of Coxiella burnetii strain Namibia

    PubMed Central

    2014-01-01

    We present the whole genome sequence and annotation of the Coxiella burnetii strain Namibia. This strain was isolated from an aborting goat in 1991 in Windhoek, Namibia. The plasmid type QpRS was confirmed in our work. Further genomic typing placed the strain into a unique genomic group. The genome sequence is 2,101,438 bp long and contains 1,979 protein-coding and 51 RNA genes, including one rRNA operon. To overcome the poor yield from cell culture systems, an additional DNA enrichment with whole genome amplification (WGA) methods was applied. We describe a bioinformatics pipeline for improved genome assembly including several filters with a special focus on WGA characteristics. PMID:25593636

  2. Structural genomics for drug design against the pathogen Coxiella burnetii.

    PubMed

    Franklin, Matthew C; Cheung, Jonah; Rudolph, Michael J; Burshteyn, Fiana; Cassidy, Michael; Gary, Ebony; Hillerich, Brandan; Yao, Zhong-Ke; Carlier, Paul R; Totrov, Maxim; Love, James D

    2015-12-01

    Coxiella burnetii is a highly infectious bacterium and potential agent of bioterrorism. However, it has not been studied as extensively as other biological agents, and very few of its proteins have been structurally characterized. To address this situation, we undertook a study of critical metabolic enzymes in C. burnetii that have great potential as drug targets. We used high-throughput techniques to produce novel crystal structures of 48 of these proteins. We selected one protein, C. burnetii dihydrofolate reductase (CbDHFR), for additional work to demonstrate the value of these structures for structure-based drug design. This enzyme's structure reveals a feature in the substrate binding groove that is different between CbDHFR and human dihydrofolate reductase (hDHFR). We then identified a compound by in silico screening that exploits this binding groove difference, and demonstrated that this compound inhibits CbDHFR with at least 25-fold greater potency than hDHFR. Since this binding groove feature is shared by many other prokaryotes, the compound identified could form the basis of a novel antibacterial agent effective against a broad spectrum of pathogenic bacteria.

  3. The Intervening Sequence of Coxiella burnetii: Characterization and Evolution

    PubMed Central

    Warrier, Indu; Walter, Mathias C.; Frangoulidis, Dimitrios; Raghavan, Rahul; Hicks, Linda D.; Minnick, Michael F.

    2016-01-01

    The intervening sequence (IVS) of Coxiella burnetii, the agent of Q fever, is a 428-nt selfish genetic element located in helix 45 of the precursor 23S rRNA. The IVS element, in turn, contains an ORF that encodes a hypothetical ribosomal S23 protein (S23p). Although S23p can be synthesized in vitro in the presence of an engineered E. coli promoter and ribosome binding site, results suggest that the protein is not synthesized in vivo. In spite of a high degree of IVS conservation among different strains of C. burnetii, the region immediately upstream of the S23p start codon is prone to change, and the S23p-encoding ORF is evidently undergoing reductive evolution. We determined that IVS excision from 23S rRNA was mediated by RNase III, and IVS RNA was rapidly degraded, thereafter. Levels of the resulting 23S rRNA fragments that flank the IVS, F1 (~1.2 kb) and F2 (~1.7 kb), were quantified over C. burnetii's logarithmic growth phase (1–5 d). Results showed that 23S F1 quantities were consistently higher than those of F2 and 16S rRNA. The disparity between levels of the two 23S rRNA fragments following excision of IVS is an interesting phenomenon of unknown significance. Based upon phylogenetic analyses, IVS was acquired through horizontal transfer after C. burnetii's divergence from an ancestral bacterium and has been subsequently maintained by vertical transfer. The widespread occurrence, maintenance and conservation of the IVS in C. burnetii imply that it plays an adaptive role or has a neutral effect on fitness.

  4. The Intervening Sequence of Coxiella burnetii: Characterization and Evolution.

    PubMed

    Warrier, Indu; Walter, Mathias C; Frangoulidis, Dimitrios; Raghavan, Rahul; Hicks, Linda D; Minnick, Michael F

    2016-01-01

    The intervening sequence (IVS) of Coxiella burnetii, the agent of Q fever, is a 428-nt selfish genetic element located in helix 45 of the precursor 23S rRNA. The IVS element, in turn, contains an ORF that encodes a hypothetical ribosomal S23 protein (S23p). Although S23p can be synthesized in vitro in the presence of an engineered E. coli promoter and ribosome binding site, results suggest that the protein is not synthesized in vivo. In spite of a high degree of IVS conservation among different strains of C. burnetii, the region immediately upstream of the S23p start codon is prone to change, and the S23p-encoding ORF is evidently undergoing reductive evolution. We determined that IVS excision from 23S rRNA was mediated by RNase III, and IVS RNA was rapidly degraded, thereafter. Levels of the resulting 23S rRNA fragments that flank the IVS, F1 (~1.2 kb) and F2 (~1.7 kb), were quantified over C. burnetii's logarithmic growth phase (1-5 d). Results showed that 23S F1 quantities were consistently higher than those of F2 and 16S rRNA. The disparity between levels of the two 23S rRNA fragments following excision of IVS is an interesting phenomenon of unknown significance. Based upon phylogenetic analyses, IVS was acquired through horizontal transfer after C. burnetii's divergence from an ancestral bacterium and has been subsequently maintained by vertical transfer. The widespread occurrence, maintenance and conservation of the IVS in C. burnetii imply that it plays an adaptive role or has a neutral effect on fitness. PMID:27595093

  5. The Intervening Sequence of Coxiella burnetii: Characterization and Evolution

    PubMed Central

    Warrier, Indu; Walter, Mathias C.; Frangoulidis, Dimitrios; Raghavan, Rahul; Hicks, Linda D.; Minnick, Michael F.

    2016-01-01

    The intervening sequence (IVS) of Coxiella burnetii, the agent of Q fever, is a 428-nt selfish genetic element located in helix 45 of the precursor 23S rRNA. The IVS element, in turn, contains an ORF that encodes a hypothetical ribosomal S23 protein (S23p). Although S23p can be synthesized in vitro in the presence of an engineered E. coli promoter and ribosome binding site, results suggest that the protein is not synthesized in vivo. In spite of a high degree of IVS conservation among different strains of C. burnetii, the region immediately upstream of the S23p start codon is prone to change, and the S23p-encoding ORF is evidently undergoing reductive evolution. We determined that IVS excision from 23S rRNA was mediated by RNase III, and IVS RNA was rapidly degraded, thereafter. Levels of the resulting 23S rRNA fragments that flank the IVS, F1 (~1.2 kb) and F2 (~1.7 kb), were quantified over C. burnetii's logarithmic growth phase (1–5 d). Results showed that 23S F1 quantities were consistently higher than those of F2 and 16S rRNA. The disparity between levels of the two 23S rRNA fragments following excision of IVS is an interesting phenomenon of unknown significance. Based upon phylogenetic analyses, IVS was acquired through horizontal transfer after C. burnetii's divergence from an ancestral bacterium and has been subsequently maintained by vertical transfer. The widespread occurrence, maintenance and conservation of the IVS in C. burnetii imply that it plays an adaptive role or has a neutral effect on fitness. PMID:27595093

  6. Right on Q: genetics begin to unravel Coxiella burnetii host cell interactions.

    PubMed

    Larson, Charles L; Martinez, Eric; Beare, Paul A; Jeffrey, Brendan; Heinzen, Robert A; Bonazzi, Matteo

    2016-07-01

    Invasion of macrophages and replication within an acidic and degradative phagolysosome-like vacuole are essential for disease pathogenesis by Coxiella burnetii, the bacterial agent of human Q fever. Previous experimental constraints imposed by the obligate intracellular nature of Coxiella limited knowledge of pathogen strategies that promote infection. Fortunately, new genetic tools facilitated by axenic culture now allow allelic exchange and transposon mutagenesis approaches for virulence gene discovery. Phenotypic screens have illuminated the critical importance of Coxiella's type 4B secretion system in host cell subversion and discovered genes encoding translocated effector proteins that manipulate critical infection events. Here, we highlight the cellular microbiology and genetics of Coxiella and how recent technical advances now make Coxiella a model organism to study macrophage parasitism. PMID:27418426

  7. Detection and differentiation of coxiella burnetii in biological fluids

    DOEpatents

    Frazier, Marvin E.; Mallavia, Louis P.; Samuel, James E.; Baca, Oswald G.

    1993-01-01

    Methods for detecting the presence of Coxiella burnetii in biological samples, as well as a method for differentiating strains of C. burnetii that are capable of causing acute disease from those strains capable of causing chronic disease are disclosed. The methods generally comprise treating cells contained within the biological sample to expose cellular DNA, and hybridizing the cellular DNA with a DNA probe containing DNA sequences that specifically hybridize with C. burnetii DNA of strains associated with the capacity to cause acute or chronic disease.

  8. Detection and differentiation of coxiella burnetii in biological fluids

    DOEpatents

    Frazier, Marvin E.; Mallavia, Louis P.; Baca, Oswald G.; Samuel, James E.

    1989-01-01

    Methods for detecting the presence of Coxiella burnetii in biological samples, as well as a method for differentiating strains of C. burnetii that are capable of causing acute disease from those strains capable of causing chronic disease are disclosed. The methods generally comprise treating cells contained within the biological sample to expose cellular DNA, and hybridizing the cellular DNA (specifically rickettsial DNA) with a C. burnetii-specific labeled DNA probe. Radioisotope and biotin labels are preferred, allowing detection through autoradiography and colorimetric assays, respectively.

  9. Coxiella burnetii in Central Italy: Novel Genotypes Are Circulating in Cattle and Goats

    PubMed Central

    Di Domenico, Marco; Curini, Valentina; De Massis, Fabrizio; Di Provvido, Andrea; Scacchia, Massimo

    2014-01-01

    Abstract Genotyping of bacteria is critical for diagnosis, treatment, and epidemiological surveillance. Coxiella burnetii, the etiological agent of Q fever, has been recognized to have a potential for bioterrorism purposes. Because few serosurveys have been conducted in Italy, there is still limited information about the distribution of this pathogen in natural conditions. In this paper, we describe the genotyping of C. burnetii strains by multispacer sequence typing (MST) detected in cattle and goat farms in the Abruzzi region of Italy. Biological samples (milk, aborted fetus) positive for C. burnetii DNA were sequenced in the spacer regions and compared with those already publicly available (http://ifr48.timone.univ-mrs.fr/MST_Coxiella/mst/group_detail). The MST profile of C. burnetii detected in milk samples demonstrated the presence of a new allele, whereas the C. burnetii spacer sequences from fetus and milk goat samples displayed a new allelic combination. The results suggest the circulation of novel genotypes of C. burnetii in Italy. PMID:25325314

  10. Detection of Coxiella burnetii in commercially available raw milk from the United States.

    PubMed

    Loftis, Amanda D; Priestley, Rachael A; Massung, Robert F

    2010-12-01

    Unpasteurized (raw) milk can be purchased in 39 U.S. states, with direct consumer purchase for human consumption permitted in 29 of those 39 states. Raw milk (n=21; cow, 14; goat, 7) was purchased in 12 states, and Coxiella burnetii, the agent of Q fever, was detected in 9 of 21 (42.9%) samples tested by polymerase chain reaction. Viability of the pathogen was demonstrated by isolation of the agent in tissue culture. The demonstration of viable C. burnetii in commercially available raw milk poses a potential public health risk.

  11. Detection of Coxiella burnetii in buffaloes aborted fetuses by IS111 DNA amplification: a preliminary report.

    PubMed

    Perugini, A G; Capuano, F; Esposito, A; Marianelli, C; Martucciello, A; Iovane, G; Galiero, G

    2009-10-01

    The aim of this study was to evaluate by PCR analyses the presence of Coxiella burnetii infection in fetuses of water buffalo (Bubalus bubalis) in the Campania region (Southern Italy). Samples were collected only from aborted fetuses and C. burnetii presence was evaluated by one-tube nested PCR amplification of the IS111 repetitive element. Of the 164 fetuses examined 14 (17.5%) were positive after DNA amplification, showing that C. burnetii occurs in this population of water buffaloes. However, more extensive prevalence studies need to be carried out to define the role of buffaloes as reservoirs for this pathogen and also the role of C. burnetii as an abortive agent in this animal.

  12. Biochemistry of Coxiella burnetii: Embden-Meyerhof pathway.

    PubMed

    McDonald, T L; Mallavia, L

    1971-09-01

    Purified preparations of Coxiella burnetii were examined for enzymes of the glycolytic pathway. Glucose-phosphate isomerase, fructose-1,6-diphosphatase, aldolase, glyceraldehyde-3-phosphate dehydrogenase, and pyruvate kinase were shown to be present in C. burnetii extracts. Heat-killed C. burnetii purified with normal yolk sacs demonstrated no activity after disruption. Aldolase was shown to be of the class II type by complete inhibition of activity in the presence of 8 x 10(-3)m ethylenediaminetetraacetic acid. The host enzyme activity (normal and infected yolk sacs) was not affected by the same treatment. When cellulose acetate electrophoresis was performed on the extracts, aldolase from both normal and infected yolk sacs exhibited five isozyme bands, whereas aldolase from the C. burnetii extract appeared as a single band.

  13. Coxiella burnetii infections in sheep or goats: an opinionated review.

    PubMed

    Van den Brom, R; van Engelen, E; Roest, H I J; van der Hoek, W; Vellema, P

    2015-12-14

    Q fever is an almost ubiquitous zoonosis caused by Coxiella burnetii, which is able to infect several animal species, as well as humans. Cattle, sheep and goats are the primary animal reservoirs. In small ruminants, infections are mostly without clinical symptoms, however, abortions and stillbirths can occur, mainly during late pregnancy. Shedding of C. burnetii occurs in feces, milk and, mostly, in placental membranes and birth fluids. During parturition of infected small ruminants, bacteria from birth products become aerosolized. Transmission to humans mainly happens through inhalation of contaminated aerosols. In the last decade, there have been several, sometimes large, human Q fever outbreaks related to sheep and goats. In this review, we describe C. burnetii infections in sheep and goats, including both advantages and disadvantages of available laboratory techniques, as pathology, different serological tests, PCR and culture to detect C. burnetii. Moreover, worldwide prevalences of C. burnetii in small ruminants are described, as well as possibilities for treatment and prevention. Prevention of shedding and subsequent environmental contamination by vaccination of sheep and goats with a phase I vaccine are possible. In addition, compulsory surveillance of C. burnetii in small ruminant farms raises awareness and hygiene measures in farms help to decrease exposure of people to the organism. Finally, this review challenges how to contain an infection of C. burnetii in small ruminants, bearing in mind possible consequences for the human population and probable interference of veterinary strategies, human risk perception and political considerations.

  14. Coxiella burnetii infections in sheep or goats: an opinionated review.

    PubMed

    Van den Brom, R; van Engelen, E; Roest, H I J; van der Hoek, W; Vellema, P

    2015-12-14

    Q fever is an almost ubiquitous zoonosis caused by Coxiella burnetii, which is able to infect several animal species, as well as humans. Cattle, sheep and goats are the primary animal reservoirs. In small ruminants, infections are mostly without clinical symptoms, however, abortions and stillbirths can occur, mainly during late pregnancy. Shedding of C. burnetii occurs in feces, milk and, mostly, in placental membranes and birth fluids. During parturition of infected small ruminants, bacteria from birth products become aerosolized. Transmission to humans mainly happens through inhalation of contaminated aerosols. In the last decade, there have been several, sometimes large, human Q fever outbreaks related to sheep and goats. In this review, we describe C. burnetii infections in sheep and goats, including both advantages and disadvantages of available laboratory techniques, as pathology, different serological tests, PCR and culture to detect C. burnetii. Moreover, worldwide prevalences of C. burnetii in small ruminants are described, as well as possibilities for treatment and prevention. Prevention of shedding and subsequent environmental contamination by vaccination of sheep and goats with a phase I vaccine are possible. In addition, compulsory surveillance of C. burnetii in small ruminant farms raises awareness and hygiene measures in farms help to decrease exposure of people to the organism. Finally, this review challenges how to contain an infection of C. burnetii in small ruminants, bearing in mind possible consequences for the human population and probable interference of veterinary strategies, human risk perception and political considerations. PMID:26315774

  15. Detection and differentiation of coxiella burnetii in biological fluids

    DOEpatents

    Frazier, Marvin E.; Mallavia, Louis P.; Samuel, James E.; Baca, Oswald G.

    1990-01-01

    Methods for detecting the presence of Coxiella burenetii in biological samples, as well as a method for differentiating strains of C. burnetii that are capable of causing acute disease from those strains capable of causing chronic disease are disclosed. The methods generally comprise treating cells contained within the biological sample to expose cellular DNA, and hybridizing the cellular DNA (specifically rickettsial DNA) with a C. burnetii-specific labeled DNA probe. Radioisotope and biotin labels are preferred, allowing detection through autoradiography and colorimetric assays, respectively.

  16. Detection and Genotyping of Coxiella burnetii and Coxiella-Like Bacteria in Horses in South Korea

    PubMed Central

    Seo, Min-Goo; Lee, Seung-Hun; VanBik, Dorene; Ouh, In-Ohk; Yun, Sun-Hee; Choi, Eunsang; Park, Yong-Soo; Lee, Sang-Eun; Kim, Jong Wan; Cho, Gil-Jae; Kwon, Oh-Deog

    2016-01-01

    Coxiella burnetii and Coxiella-like bacteria (CLB) are genetically and ecologically distinct despite some genetic similarities. Furthermore, CLB are exceptionally diverse and widespread in ticks, but rarely detected in domestic animals. Since Coxiella bacteria can be transmitted from infected horses by inhalation or by coming in contact with ticks during activities such as horseback riding, it is necessary to study their prevalence. To the best of our knowledge, this is the first large-scale nationwide investigation of the prevalence of C. burnetii and CLB among horses reared in South Korea. Of 816 blood samples collected between 2007 and 2013, 11 (1.3%) were identified as C. burnetii by ELISA, and six (0.7%) as CLB by 16S rRNA sequencing. While a sequence from Jeju Island was similar (97.9–100%) to those within clade B, five sequences obtained from the northern region were categorized into a new clade, indicating the sequence diversity of the genus Coxiella. Studies until date had detected CLB only in ticks; here, we describe their detection in mammals. Given their zoonotic potential, strategic monitoring and appropriate control programs for Coxiella species need to be established. PMID:27244230

  17. Detection and Genotyping of Coxiella burnetii and Coxiella-Like Bacteria in Horses in South Korea.

    PubMed

    Seo, Min-Goo; Lee, Seung-Hun; VanBik, Dorene; Ouh, In-Ohk; Yun, Sun-Hee; Choi, Eunsang; Park, Yong-Soo; Lee, Sang-Eun; Kim, Jong Wan; Cho, Gil-Jae; Kwon, Oh-Deog; Kwak, Dongmi

    2016-01-01

    Coxiella burnetii and Coxiella-like bacteria (CLB) are genetically and ecologically distinct despite some genetic similarities. Furthermore, CLB are exceptionally diverse and widespread in ticks, but rarely detected in domestic animals. Since Coxiella bacteria can be transmitted from infected horses by inhalation or by coming in contact with ticks during activities such as horseback riding, it is necessary to study their prevalence. To the best of our knowledge, this is the first large-scale nationwide investigation of the prevalence of C. burnetii and CLB among horses reared in South Korea. Of 816 blood samples collected between 2007 and 2013, 11 (1.3%) were identified as C. burnetii by ELISA, and six (0.7%) as CLB by 16S rRNA sequencing. While a sequence from Jeju Island was similar (97.9-100%) to those within clade B, five sequences obtained from the northern region were categorized into a new clade, indicating the sequence diversity of the genus Coxiella. Studies until date had detected CLB only in ticks; here, we describe their detection in mammals. Given their zoonotic potential, strategic monitoring and appropriate control programs for Coxiella species need to be established. PMID:27244230

  18. Detection and Genotyping of Coxiella burnetii and Coxiella-Like Bacteria in Horses in South Korea.

    PubMed

    Seo, Min-Goo; Lee, Seung-Hun; VanBik, Dorene; Ouh, In-Ohk; Yun, Sun-Hee; Choi, Eunsang; Park, Yong-Soo; Lee, Sang-Eun; Kim, Jong Wan; Cho, Gil-Jae; Kwon, Oh-Deog; Kwak, Dongmi

    2016-01-01

    Coxiella burnetii and Coxiella-like bacteria (CLB) are genetically and ecologically distinct despite some genetic similarities. Furthermore, CLB are exceptionally diverse and widespread in ticks, but rarely detected in domestic animals. Since Coxiella bacteria can be transmitted from infected horses by inhalation or by coming in contact with ticks during activities such as horseback riding, it is necessary to study their prevalence. To the best of our knowledge, this is the first large-scale nationwide investigation of the prevalence of C. burnetii and CLB among horses reared in South Korea. Of 816 blood samples collected between 2007 and 2013, 11 (1.3%) were identified as C. burnetii by ELISA, and six (0.7%) as CLB by 16S rRNA sequencing. While a sequence from Jeju Island was similar (97.9-100%) to those within clade B, five sequences obtained from the northern region were categorized into a new clade, indicating the sequence diversity of the genus Coxiella. Studies until date had detected CLB only in ticks; here, we describe their detection in mammals. Given their zoonotic potential, strategic monitoring and appropriate control programs for Coxiella species need to be established.

  19. Host Kinase Activity is Required for Coxiella burnetii Parasitophorous Vacuole Formation.

    PubMed

    Hussain, S Kauser; Broederdorf, Laura J; Sharma, Uma M; Voth, Daniel E

    2010-01-01

    Coxiella burnetii is the etiologic agent of human Q fever and targets alveolar phagocytic cells in vivo wherein the pathogen generates a phagolysosome-like parasitophorous vacuole (PV) for replication. C. burnetii displays a prolonged growth cycle, making PV maintenance critical for bacterial survival. Previous studies showed that C. burnetii mediates activation of eukaryotic kinases to inhibit cell death, indicating the importance of host signaling during infection. In the current study, we examined the role of eukaryotic kinase signaling in PV establishment. A panel of 113 inhibitors was analyzed for their impact on C. burnetii infection of human THP-1 macrophage-like cells and HeLa cells. Inhibition of 11 kinases or two phosphatases altered PV formation and prevented pathogen growth, with most inhibitor-treated cells harboring organisms in tight-fitting phagosomes, indicating kinase/phosphatase activation is required for PV maturation. Five inhibitors targeted protein kinase C (PKC), suggesting a critical role for this protein during intracellular growth. The PKC-specific substrate MARCKS was phosphorylated at 24 h post-infection and remained phosphorylated through 5 days post-infection, indicating prolonged regulation of the PKC pathway by C. burnetii. Infection also altered the activation status of p38, myosin light chain kinase, and cAMP-dependent protein kinase, suggesting C. burnetii subverts numerous phosphorylation cascades. These results underscore the importance of intracellular host signaling for C. burnetii PV biogenesis.

  20. Coxiella burnetii exposure in northern sea otters Enhydra lutris kenyoni.

    PubMed

    Duncan, Colleen; Gill, Verena A; Worman, Kristin; Burek-Huntington, Kathy; Pabilonia, Kristy L; Johnson, Sam; Fitzpatrick, Kelly A; Weller, Christina; Kersh, Gilbert J

    2015-05-11

    Valvular endocarditis has been well described in northern sea otters Enhydra lutris kenyoni of Alaska and in many cases no cause has been identified. It is also one of the most common conditions observed in people with chronic Coxiella burnetii infection. Given the high levels of C. burnetii exposure in marine mammals distributed throughout the same geographic range as the northern sea otter, and the presence of valvular lesions seen in otters, the objective of this study was to determine the level of C. burnetii exposure in otters and investigate any association between exposure, infection and valvular disease in this species. Archived serum from 75 live captured, apparently healthy otters (25 from each of 3 stocks) and 30 dead otters were tested for C. burnetii antibodies by indirect florescent antibody assay (IFA). Archived bone marrow and heart valves were tested for C. burnetii DNA by real-time PCR (qPCR). Overall, the seroprevalence in live otters was 17%, with significantly more exposed animals in the south central (40%) stock relative to the southwest (8%) and southeast (4%). The seroprevalence of animals sampled post mortem was 27%, although none of the bone marrow or heart valve samples were positive by qPCR. Results of this study failed to demonstrate a significant association between C. burnetii infection and valvular endocarditis in sea otters; however, the differing seroprevalence suggests that exposure opportunities vary geographically.

  1. Coxiella burnetii exposure in northern sea otters Enhydra lutris kenyoni.

    PubMed

    Duncan, Colleen; Gill, Verena A; Worman, Kristin; Burek-Huntington, Kathy; Pabilonia, Kristy L; Johnson, Sam; Fitzpatrick, Kelly A; Weller, Christina; Kersh, Gilbert J

    2015-05-11

    Valvular endocarditis has been well described in northern sea otters Enhydra lutris kenyoni of Alaska and in many cases no cause has been identified. It is also one of the most common conditions observed in people with chronic Coxiella burnetii infection. Given the high levels of C. burnetii exposure in marine mammals distributed throughout the same geographic range as the northern sea otter, and the presence of valvular lesions seen in otters, the objective of this study was to determine the level of C. burnetii exposure in otters and investigate any association between exposure, infection and valvular disease in this species. Archived serum from 75 live captured, apparently healthy otters (25 from each of 3 stocks) and 30 dead otters were tested for C. burnetii antibodies by indirect florescent antibody assay (IFA). Archived bone marrow and heart valves were tested for C. burnetii DNA by real-time PCR (qPCR). Overall, the seroprevalence in live otters was 17%, with significantly more exposed animals in the south central (40%) stock relative to the southwest (8%) and southeast (4%). The seroprevalence of animals sampled post mortem was 27%, although none of the bone marrow or heart valve samples were positive by qPCR. Results of this study failed to demonstrate a significant association between C. burnetii infection and valvular endocarditis in sea otters; however, the differing seroprevalence suggests that exposure opportunities vary geographically. PMID:25958809

  2. Coxiella burnetii in Humans and Ticks in Rural Senegal

    PubMed Central

    Mediannikov, Oleg; Fenollar, Florence; Socolovschi, Cristina; Diatta, Georges; Bassene, Hubert; Molez, Jean-François; Sokhna, Cheikh; Trape, Jean-François; Raoult, Didier

    2010-01-01

    Background Q fever is a worldwide zoonotic disease caused by Coxiella burnetii. Epidemiologically, animals are considered reservoirs and humans incidental hosts. Methodology/Principal Findings We investigated Q fever in rural Senegal. Human samples (e.g., sera, saliva, breast milk, feces) were screened in the generally healthy population of two villages of the Sine-Saloum region. Ticks were collected in four regions. Seroprevalence was studied by immunofluorescence, and all other samples were tested by two qPCR systems for detection of C. burnetii. Positive samples were genotyped (multispacer typing) by amplification and sequencing of three spacers. Strains were isolated by cell culture. We found that the seroprevalence may be as high as 24.5% (59 of 238 studied) in Dielmo village. We identified spontaneous excretion of C. burnetii by humans through faeces and milk. Hard and soft ticks (8 species) were infected in 0–37.6%. We identified three genotypes of C. burnetii. The previously identified genotype 6 was the most common in ticks in all studied regions and the only one found in human samples. Three strains of genotype 6 of C. burnetii were also recovered from soft tick Ornithodoros sonrai. Two other genotypes found in ticks, 35 and 36, were identified for the first time. Conclusions/Significance Q fever should be considered a significant public health threat in Senegal. Humans, similar to other mammals, may continuously excrete C. burnetii. PMID:20386603

  3. Endocytic SNAREs are involved in optimal Coxiella burnetii vacuole development.

    PubMed

    Campoy, Emanuel Martín; Mansilla, María Eugenia; Colombo, María Isabel

    2013-06-01

    Coxiella burnetii is a Gram-negative intracellular bacterium. As previously described, both the endocytic and the autophagic pathways contribute to the maturation of Coxiella replicative vacuoles (CRVs). The large CRVs share the properties of both phagolysosomal and autophagolysosomal compartments. Vamp3, Vamp7 and Vamp8 are v-SNAREs involved in the endocytic pathway which participate mainly in the fusion between endosomes and lysosomes. In the present study we observed that Vamp7 interacts with C. burnetii at different infection times (1 h-48 h p.i.). We have determined that a truncated mutant of Vamp7 (Vamp7 NT) and a siRNA against this SNARE protein affects the optimal development of CRVs, suggesting that Vamp7 mediates fusion events that are required for the biogenesis of CRVs. Indeed, we have observed that overexpression of Vamp7 NT inhibited the heterotypic fusion with lysosomes and the homotypic fusion between individual Coxiella phagosomes and CRVs. Moreover, we have detected in the vacuole membrane, at different infection times, the Vamp7 partners (Vti1a and Vti1b). Interestingly, treatment with chloramphenicol reduced the colocalization between C. burnetii and Vamp7, Vti1a or Vti1b, indicating that the recruitment of these SNAREs proteins is a bacteria-driven process that favours the CRV biogenesis, likely by facilitating the interaction with the endolysosomal compartment.

  4. Molecular methods routinely used to detect Coxiella burnetii in ticks cross-react with Coxiella-like bacteria

    PubMed Central

    Elsa, Jourdain; Duron, Olivier; Séverine, Barry; González-Acuña, Daniel; Sidi-Boumedine, Karim

    2015-01-01

    Background Q fever is a widespread zoonotic disease caused by Coxiella burnetii. Ticks may act as vectors, and many epidemiological studies aim to assess C. burnetii prevalence in ticks. Because ticks may also be infected with Coxiella-like bacteria, screening tools that differentiate between C. burnetii and Coxiella-like bacteria are essential. Methods In this study, we screened tick specimens from 10 species (Ornithodoros rostratus, O. peruvianus, O. capensis, Ixodes ricinus, Rhipicephalus annulatus, R. decoloratus, R. geigy, O. sonrai, O. occidentalis, and Amblyomma cajennense) known to harbor specific Coxiella-like bacteria, by using quantitative PCR primers usually considered to be specific for C. burnetii and targeting, respectively, the IS1111, icd, scvA, p1, and GroEL/htpB genes. Results We found that some Coxiella-like bacteria, belonging to clades A and C, yield positive PCR results when screened with primers initially believed to be C. burnetii-specific. Conclusions These results suggest that PCR-based surveys that aim to detect C. burnetii in ticks by using currently available methods must be interpreted with caution if the amplified products cannot be sequenced. Future molecular methods that aim at detecting C. burnetii need to take into account the possibility that cross-reactions may exist with Coxiella-like bacteria. PMID:26609691

  5. Coxiella burnetii Transcriptional Analysis Reveals Serendipity Clusters of Regulation in Intracellular Bacteria

    PubMed Central

    Leroy, Quentin; Lebrigand, Kevin; Armougom, Fabrice; Barbry, Pascal; Thiéry, Richard; Raoult, Didier

    2010-01-01

    Coxiella burnetii, the causative agent of the zoonotic disease Q fever, is mainly transmitted to humans through an aerosol route. A spore-like form allows C. burnetii to resist different environmental conditions. Because of this, analysis of the survival strategies used by this bacterium to adapt to new environmental conditions is critical for our understanding of C. burnetii pathogenicity. Here, we report the early transcriptional response of C. burnetii under temperature stresses. Our data show that C. burnetii exhibited minor changes in gene regulation under short exposure to heat or cold shock. While small differences were observed, C. burnetii seemed to respond similarly to cold and heat shock. The expression profiles obtained using microarrays produced in-house were confirmed by quantitative RT-PCR. Under temperature stresses, 190 genes were differentially expressed in at least one condition, with a fold change of up to 4. Globally, the differentially expressed genes in C. burnetii were associated with bacterial division, (p)ppGpp synthesis, wall and membrane biogenesis and, especially, lipopolysaccharide and peptidoglycan synthesis. These findings could be associated with growth arrest and witnessed transformation of the bacteria to a spore-like form. Unexpectedly, clusters of neighboring genes were differentially expressed. These clusters do not belong to operons or genetic networks; they have no evident associated functions and are not under the control of the same promoters. We also found undescribed but comparable clusters of regulation in previously reported transcriptomic analyses of intracellular bacteria, including Rickettsia sp. and Listeria monocytogenes. The transcriptomic patterns of C. burnetii observed under temperature stresses permits the recognition of unpredicted clusters of regulation for which the trigger mechanism remains unidentified but which may be the result of a new mechanism of epigenetic regulation. PMID:21203564

  6. Can Coxiella burnetii be transmitted by embryo transfer in goats?

    PubMed

    Alsaleh, A; Fieni, F; Rodolakis, A; Bruyas, J F; Roux, C; Larrat, M; Chatagnon, G; Pellerin, J L

    2013-10-01

    The detection of significant bacterial loads of Coxiella burnetii in flushing media and tissue samples from the genital tracts of nonpregnant goats represents a risk factor for in utero infection and transmission during embryo transfer. The aim of this study was to investigate (1) whether cells of early goat embryos isolated from in vivo-fertilized goats interact with C. burnetii in vitro, (2) whether the embryonic zona pellucida (ZP) protects early embryo cells from infection, and (3) the efficacy of the International Embryo Transfer Society (IETS) washing protocol for bovine embryos. The study was performed in triple replicate: 12 donor goats, certified negative by ELISA and polymerase chain reaction, were synchronized, superovulated, and subsequently inseminated by Q fever-negative males. Sixty-eight embryos were collected 4 days later by laparotomy. Two-thirds of the resulting ZP-intact and ZP-free 8- to 16-cell embryos (9-9, 11-11, and 4-4 in replicates 1, 2, and 3, respectively) were placed in 1 mL minimum essential medium containing 10(9)C. burnetii CBC1 (IASP, INRA Tours). After overnight incubation at 37 °C and 5% CO2, the embryos were washed according to the IETS procedure. In parallel, the remaining third ZP-intact and ZP-free uninfected embryos (3-3, 5-5, and 2-2 in replicates 1, 2, and 3, respectively) were subjected to the same procedures, but without C. burnetii, thus serving as controls. The 10 washing fluids for all batches of each replicate were collected and centrifuged for 1 hour at 13,000 × g. The washed embryos and pellets were tested by polymerase chain reaction. Coxiella burnetii DNA was found in all batches of ZP-intact and ZP-free infected embryos after 10 successive washes. It was also detected in the first five washing fluids for ZP-intact embryos and in the first eight washing fluids for ZP-free embryos. None of the control batches (embryos and washing fluids) were found to contain bacterial DNA. These results clearly indicate that

  7. Coxiella burnetii Seroprevalence in Small Ruminants in The Gambia

    PubMed Central

    Klaasen, Marieke; Roest, Hendrik-Jan; van der Hoek, Wim; Goossens, Bart; Secka, Arss; Stegeman, Arjan

    2014-01-01

    Background Q fever is a zoonosis caused by Coxiella burnetii, a Gram negative bacterium present worldwide. Small ruminants are considered the main reservoirs for infection of humans. This study aimed to estimate the extent of C. burnetii infection among sheep and goats in part of The Gambia. Methodology/Principal Findings This survey was carried out from March to May 2012 at two areas in The Gambia. The first area comprised a cluster of seven rural villages situated 5–15 km west of Farafenni as well as the local abattoir. A second sampling was done at the central abattoir in Abuko (30 km from the capital, Banjul) in the Western Region. Serum samples were obtained from 490 goats and 398 sheep. In addition, 67 milk samples were obtained from lactating dams. Sera were tested with a Q fever ELISA kit. C. burnetii DNA was extracted from milk samples and then detected using a specific quantitative multiplex PCR assay, targeting the IS1111a element. A multivariable mixed logistic regression model was used to examine the relationship between seropositivity and explanatory variables. An overall seroprevalence of 21.6% was found. Goats had a significantly higher seroprevalence than sheep, respectively 24.2% and 18.5%. Seropositive animals were significantly older than seronegative animals. Animals from the villages had a significantly lower seroprevalence than animals from the central abattoir (15.1% versus 29.1%). C. burnetii DNA was detected in 2 out of 67 milk samples, whereas 8 samples gave a doubtful result. Conclusion/Significance A substantial C. burnetii seroprevalence in sheep and goats in The Gambia was demonstrated. People living in close proximity to small ruminants are exposed to C. burnetii. Q fever should be considered as a possible cause of acute febrile illness in humans in The Gambia. Future studies should include a simultaneous assessment of veterinary and human serology, and include aetiology of febrile illness in local clinics. PMID:24454863

  8. Host cell-free growth of the Q fever bacterium Coxiella burnetii

    PubMed Central

    Omsland, Anders; Cockrell, Diane C.; Howe, Dale; Fischer, Elizabeth R.; Virtaneva, Kimmo; Sturdevant, Daniel E.; Porcella, Stephen F.; Heinzen, Robert A.

    2009-01-01

    The inability to propagate obligate intracellular pathogens under axenic (host cell-free) culture conditions imposes severe experimental constraints that have negatively impacted progress in understanding pathogen virulence and disease mechanisms. Coxiella burnetii, the causative agent of human Q (Query) fever, is an obligate intracellular bacterial pathogen that replicates exclusively in an acidified, lysosome-like vacuole. To define conditions that support C. burnetii growth, we systematically evaluated the organism's metabolic requirements using expression microarrays, genomic reconstruction, and metabolite typing. This led to development of a complex nutrient medium that supported substantial growth (approximately 3 log10) of C. burnetii in a 2.5% oxygen environment. Importantly, axenically grown C. burnetii were highly infectious for Vero cells and exhibited developmental forms characteristic of in vivo grown organisms. Axenic cultivation of C. burnetii will facilitate studies of the organism's pathogenesis and genetics and aid development of Q fever preventatives such as an effective subunit vaccine. Furthermore, the systematic approach used here may be broadly applicable to development of axenic media that support growth of other medically important obligate intracellular pathogens. PMID:19246385

  9. Prevalence of Coxiella burnetii antibodies in Portuguese dairy cattle herds.

    PubMed

    Pimenta, Luís; Alegria, Nuno; Anastácio, Sofia; Sidi-Boumedine, Karim; da Silva, Gabriela; Rabiço, Ângela; Simões, João

    2015-01-01

    Q fever is an important zoonotic disease which has been recently diagnosed, mainly in sheep and goats, in Portugal. The aim of the present study was to determine the prevalence of bovine Coxiella burnetii antibodies in dairy farms from the northwest of Portugal. Bulk tank milk samples were randomly obtained, on November 2013, from 90 dairy farms and assayed using an ELISA kit. The apparent prevalence was 61.1% (95% C.I. from 50.8 to 70.5%). The proportion of negative and intermediate (inconclusive) herds was 34.5% (25.5 to 44.7%) and 4.4% (1.7 to 10.9%), respectively. In conclusion, a high level of exposure to Coxiella burnetii was observed in Portuguese dairy cattle herds, highlighting the needs to better understand the epidemiology of Q fever in Portugal by the implementation of a monitoring program based on harmonized serologic and molecular methodologies and elucidation of the infection status of the herds. PMID:25339430

  10. When Outgroups Fail; Phylogenomics of Rooting the Emerging Pathogen, Coxiella burnetii

    PubMed Central

    Pearson, Talima; Hornstra, Heidie M.; Sahl, Jason W.; Schaack, Sarah; Schupp, James M.; Beckstrom-Sternberg, Stephen M.; O'Neill, Matthew W.; Priestley, Rachael A.; Champion, Mia D.; Beckstrom-Sternberg, James S.; Kersh, Gilbert J.; Samuel, James E.; Massung, Robert F.; Keim, Paul

    2013-01-01

    Rooting phylogenies is critical for understanding evolution, yet the importance, intricacies and difficulties of rooting are often overlooked. For rooting, polymorphic characters among the group of interest (ingroup) must be compared to those of a relative (outgroup) that diverged before the last common ancestor (LCA) of the ingroup. Problems arise if an outgroup does not exist, is unknown, or is so distant that few characters are shared, in which case duplicated genes originating before the LCA can be used as proxy outgroups to root diverse phylogenies. Here, we describe a genome-wide expansion of this technique that can be used to solve problems at the other end of the evolutionary scale: where ingroup individuals are all very closely related to each other, but the next closest relative is very distant. We used shared orthologous single nucleotide polymorphisms (SNPs) from 10 whole genome sequences of Coxiella burnetii, the causative agent of Q fever in humans, to create a robust, but unrooted phylogeny. To maximize the number of characters informative about the rooting, we searched entire genomes for polymorphic duplicated regions where orthologs of each paralog could be identified so that the paralogs could be used to root the tree. Recent radiations, such as those of emerging pathogens, often pose rooting challenges due to a lack of ingroup variation and large genomic differences with known outgroups. Using a phylogenomic approach, we created a robust, rooted phylogeny for C. burnetii. [Coxiella burnetii; paralog SNPs; pathogen evolution; phylogeny; recent radiation; root; rooting using duplicated genes.] PMID:23736103

  11. Detection of Coxiella burnetii in Ambient Air after a Large Q Fever Outbreak

    PubMed Central

    de Rooij, Myrna M. T.; Borlée, Floor; Smit, Lidwien A. M.; de Bruin, Arnout; Janse, Ingmar; Heederik, Dick J. J.; Wouters, Inge M.

    2016-01-01

    One of the largest Q fever outbreaks ever occurred in the Netherlands from 2007–2010, with 25 fatalities among 4,026 notified cases. Airborne dispersion of Coxiella burnetii was suspected but not studied extensively at the time. We investigated temporal and spatial variation of Coxiella burnetii in ambient air at residential locations in the most affected area in the Netherlands (the South-East), in the year immediately following the outbreak. One-week average ambient particulate matter < 10 μm samples were collected at eight locations from March till September 2011. Presence of Coxiella burnetii DNA was determined by quantitative polymerase chain reaction. Associations with various spatial and temporal characteristics were analyzed by mixed logistic regression. Coxiella burnetii DNA was detected in 56 out of 202 samples (28%). Airborne Coxiella burnetii presence showed a clear seasonal pattern coinciding with goat kidding. The spatial variation was significantly associated with number of goats on the nearest goat farm weighted by the distance to the farm (OR per IQR: 1.89, CI: 1.31–2.76). We conclude that in the year after a large Q fever outbreak, temporal variation of airborne Coxiella burnetii is suggestive to be associated with goat kidding, and spatial variation with distance to and size of goat farms. Aerosol measurements show to have potential for source identification and attribution of an airborne pathogen, which may also be applicable in early stages of an outbreak. PMID:26991094

  12. Detection of Coxiella burnetii in Ambient Air after a Large Q Fever Outbreak.

    PubMed

    de Rooij, Myrna M T; Borlée, Floor; Smit, Lidwien A M; de Bruin, Arnout; Janse, Ingmar; Heederik, Dick J J; Wouters, Inge M

    2016-01-01

    One of the largest Q fever outbreaks ever occurred in the Netherlands from 2007-2010, with 25 fatalities among 4,026 notified cases. Airborne dispersion of Coxiella burnetii was suspected but not studied extensively at the time. We investigated temporal and spatial variation of Coxiella burnetii in ambient air at residential locations in the most affected area in the Netherlands (the South-East), in the year immediately following the outbreak. One-week average ambient particulate matter < 10 μm samples were collected at eight locations from March till September 2011. Presence of Coxiella burnetii DNA was determined by quantitative polymerase chain reaction. Associations with various spatial and temporal characteristics were analyzed by mixed logistic regression. Coxiella burnetii DNA was detected in 56 out of 202 samples (28%). Airborne Coxiella burnetii presence showed a clear seasonal pattern coinciding with goat kidding. The spatial variation was significantly associated with number of goats on the nearest goat farm weighted by the distance to the farm (OR per IQR: 1.89, CI: 1.31-2.76). We conclude that in the year after a large Q fever outbreak, temporal variation of airborne Coxiella burnetii is suggestive to be associated with goat kidding, and spatial variation with distance to and size of goat farms. Aerosol measurements show to have potential for source identification and attribution of an airborne pathogen, which may also be applicable in early stages of an outbreak. PMID:26991094

  13. Genotyping of Coxiella burnetii from domestic ruminants in northern Spain

    PubMed Central

    2012-01-01

    Background Information on the genotypic diversity of Coxiella burnetii isolates from infected domestic ruminants in Spain is limited. The aim of this study was to identify the C. burnetii genotypes infecting livestock in Northern Spain and compare them to other European genotypes. A commercial real-time PCR targeting the IS1111a insertion element was used to detect the presence of C. burnetii DNA in domestic ruminants from Spain. Genotypes were determined by a 6-loci Multiple Locus Variable number tandem repeat analysis (MLVA) panel and Multispacer Sequence Typing (MST). Results A total of 45 samples from 4 goat herds (placentas, N = 4), 12 dairy cattle herds (vaginal mucus, individual milk, bulk tank milk, aerosols, N = 20) and 5 sheep flocks (placenta, vaginal swabs, faeces, air samples, dust, N = 21) were included in the study. Samples from goats and sheep were obtained from herds which had suffered abortions suspected to be caused by C. burnetii, whereas cattle samples were obtained from animals with reproductive problems compatible with C. burnetii infection, or consisted of bulk tank milk (BTM) samples from a Q fever surveillance programme. C. burnetii genotypes identified in ruminants from Spain were compared to those detected in other countries. Three MLVA genotypes were found in 4 goat farms, 7 MLVA genotypes were identified in 12 cattle herds and 4 MLVA genotypes were identified in 5 sheep flocks. Clustering of the MLVA genotypes using the minimum spanning tree method showed a high degree of genetic similarity between most MLVA genotypes. Overall 11 different MLVA genotypes were obtained corresponding to 4 different MST genotypes: MST genotype 13, identified in goat, sheep and cattle from Spain; MST genotype 18, only identified in goats; and, MST genotypes 8 and 20, identified in small ruminants and cattle, respectively. All these genotypes had been previously identified in animal and human clinical samples from several European countries, but

  14. Complete genome sequence of the Q-fever pathogen Coxiella burnetii

    PubMed Central

    Seshadri, Rekha; Paulsen, Ian T.; Eisen, Jonathan A.; Read, Timothy D.; Nelson, Karen E.; Nelson, William C.; Ward, Naomi L.; Tettelin, Hervé; Davidsen, Tanja M.; Beanan, Maureen J.; Deboy, Robert T.; Daugherty, Sean C.; Brinkac, Lauren M.; Madupu, Ramana; Dodson, Robert J.; Khouri, Hoda M.; Lee, Kathy H.; Carty, Heather A.; Scanlan, David; Heinzen, Robert A.; Thompson, Herbert A.; Samuel, James E.; Fraser, Claire M.; Heidelberg, John F.

    2003-01-01

    The 1,995,275-bp genome of Coxiella burnetii, Nine Mile phase I RSA493, a highly virulent zoonotic pathogen and category B bioterrorism agent, was sequenced by the random shotgun method. This bacterium is an obligate intracellular acidophile that is highly adapted for life within the eukaryotic phagolysosome. Genome analysis revealed many genes with potential roles in adhesion, invasion, intracellular trafficking, host-cell modulation, and detoxification. A previously uncharacterized 13-member family of ankyrin repeat-containing proteins is implicated in the pathogenesis of this organism. Although the lifestyle and parasitic strategies of C. burnetii resemble that of Rickettsiae and Chlamydiae, their genome architectures differ considerably in terms of presence of mobile elements, extent of genome reduction, metabolic capabilities, and transporter profiles. The presence of 83 pseudogenes displays an ongoing process of gene degradation. Unlike other obligate intracellular bacteria, 32 insertion sequences are found dispersed in the chromosome, indicating some plasticity in the C. burnetii genome. These analyses suggest that the obligate intracellular lifestyle of C. burnetii may be a relatively recent innovation. PMID:12704232

  15. Coxiella burnetii DNA detected in domestic ruminants and wildlife from Portugal.

    PubMed

    Cumbassá, Aminata; Barahona, Maria J; Cunha, Mónica V; Azórin, Beatriz; Fonseca, Carlos; Rosalino, Luís Miguel; Tilburg, Jeroen; Hagen, Ferry; Santos, Ana S; Botelho, Ana

    2015-10-22

    Coxiella burnetii is the etiological agent of Q fever or Coxiellosis, a zoonosis mainly affecting domestic ruminants. Information on the population structure and epidemiology of C. burnetii in animals is scarce in Portugal. Evidence of C. burnetti infection was sought in domestic, wild and captive animals based on the detection of bacterial DNA. Tissue samples from 152 domestic animals (cattle=24, goats=51, sheep=76 and swine=1), 55 wild carnivores (Egyptian mongoose=45, red fox=4, common genet=3, weasel=2 and European badger=1) and 22 zoo animals (antelopes=15, impala=1; rhinoceros=1, deer=2, zebras=2 and giraffe=1) were screened by nested-touchdown PCR. Cloacae swabs from 19 griffon vultures were also analysed. Among the domestic ruminants, goats presented the highest prevalence of infection (23.53%), followed by cattle, (20.83%) and sheep (10.53%). C. burnetii DNA was also detected in five Egyptian mongooses and two antelopes and one giraffe. Using a 6-locus multiple-locus variable-number tandem repeat analysis (MLVA-6) six complete genotypes, T, I and CM and the first reported CN, CO and CP, were identified, respectively, in small ruminants and Egyptian mongooses. Clustering analysis of genotypes exposed four distinct groups, according to detection source, enlightening an apparent association between C. burnetii genotype and host.

  16. Coxiella burnetii DNA detected in domestic ruminants and wildlife from Portugal.

    PubMed

    Cumbassá, Aminata; Barahona, Maria J; Cunha, Mónica V; Azórin, Beatriz; Fonseca, Carlos; Rosalino, Luís Miguel; Tilburg, Jeroen; Hagen, Ferry; Santos, Ana S; Botelho, Ana

    2015-10-22

    Coxiella burnetii is the etiological agent of Q fever or Coxiellosis, a zoonosis mainly affecting domestic ruminants. Information on the population structure and epidemiology of C. burnetii in animals is scarce in Portugal. Evidence of C. burnetti infection was sought in domestic, wild and captive animals based on the detection of bacterial DNA. Tissue samples from 152 domestic animals (cattle=24, goats=51, sheep=76 and swine=1), 55 wild carnivores (Egyptian mongoose=45, red fox=4, common genet=3, weasel=2 and European badger=1) and 22 zoo animals (antelopes=15, impala=1; rhinoceros=1, deer=2, zebras=2 and giraffe=1) were screened by nested-touchdown PCR. Cloacae swabs from 19 griffon vultures were also analysed. Among the domestic ruminants, goats presented the highest prevalence of infection (23.53%), followed by cattle, (20.83%) and sheep (10.53%). C. burnetii DNA was also detected in five Egyptian mongooses and two antelopes and one giraffe. Using a 6-locus multiple-locus variable-number tandem repeat analysis (MLVA-6) six complete genotypes, T, I and CM and the first reported CN, CO and CP, were identified, respectively, in small ruminants and Egyptian mongooses. Clustering analysis of genotypes exposed four distinct groups, according to detection source, enlightening an apparent association between C. burnetii genotype and host. PMID:26345258

  17. Proteomic and Systems Biology Analysis of the Monocyte Response to Coxiella burnetii Infection

    PubMed Central

    Shipman, Matt; Lubick, Kirk; Fouchard, David; Gurram, Rajani; Grieco, Paul; Jutila, Mark; Dratz, Edward A.

    2013-01-01

    Coxiella burnetii is an obligate intracellular bacterial pathogen and the causative agent of Q fever. Chronic Q fever can produce debilitating fatigue and C. burnetii is considered a significant bioterror threat. C. burnetii occupies the monocyte phagolysosome and although prior work has explained features of the host-pathogen interaction, many aspects are still poorly understood. We have conducted a proteomic investigation of human Monomac I cells infected with the Nine Mile Phase II strain of C. burnetii and used the results as a framework for a systems biology model of the host response. Our principal methodology was multiplex differential 2D gel electrophoresis using ZDyes, a new generation of covalently linked fluorescent protein detection dyes under development at Montana State University. The 2D gel analysis facilitated the detection of changes in posttranslational modifications on intact proteins in response to infection. The systems model created from our data a framework for the design of experiments to seek a deeper understanding of the host-pathogen interactions. PMID:23990884

  18. Coxiella burnetii seroprevalence and associated risk factors in dairy and mixed cattle farms from Ecuador.

    PubMed

    Carbonero, Alfonso; Guzmán, Lucía T; Montaño, Karen; Torralbo, Alicia; Arenas-Montes, Antonio; Saa, Luis R

    2015-03-01

    Q fever is a zoonotic disease caused by Coxiella burnetii, a bacterial agent for which ruminants are the main reservoir. An extensive cross-sectional study to determine the seroprevalence of and associated risk factors for Q fever was performed in dairy and mixed (dairy-beef) cattle herds in Ecuador. A total of 2668 serum samples from 386 herds were analyzed using an ELISA. In addition, a questionnaire with 57 variables related to management, feeding, facilities, biosecurity and animal health was completed for every cattle farm. A Generalized Estimating Equations model was used to determine the factors associated with C. burnetii seropositivity. The true prevalence of C. burnetii seropositivity in dairy and mixed cattle from Ecuador reached 12.6% (CI95%: 11.3-13.9%). The herd prevalence was 46.9% (181/386) (CI95%: 41.9-51.9%), and the within herd prevalence ranged between 8% and 100% (mean: 25.0%; Q1: 12.5%, Q2: 25.0%, Q3: 37.5%). Four factors were included in the GEE model for C. burnetii seropositivity: age of the cattle (OR: 1.01; CI95%: 1.006-1.014), feeding of calves with milk replacers (OR: 1.94; CI95%: 1.1-3.3), bovine respiratory syncytial virus seropositivity (OR: 1.54; CI95%: 1.1-2.3), and disinfection of the umbilical cord (OR: 0.60; CI95%: 0.4-0.9).

  19. Whole genome PCR scanning (WGPS) of Coxiella burnetii strains from ruminants.

    PubMed

    Sidi-Boumedine, Karim; Adam, Gilbert; Angen, Øysten; Aspán, Anna; Bossers, Alex; Roest, Hendrik-Jan; Prigent, Myriam; Thiéry, Richard; Rousset, Elodie

    2015-01-01

    Coxiella burnetii is the causative agent of Q fever, a zoonosis that spreads from ruminants to humans via the inhalation of aerosols contaminated by livestock's birth products. This study aimed to compare the genomes of strains isolated from ruminants by "Whole Genome PCR Scanning (WGPS)" in order to identify genomic differences. C. burnetii isolated from different ruminant hosts were compared to the Nine Mile reference strain using WGPS. The identified genomic regions of differences (RDs) were confirmed by sequencing. A set of 219 primers for amplification of 10 kbp segments covering the entire genome was obtained. The analyses revealed the presence of: i) conserved genomic regions, ii) genomic polymorphism including insertions and deletions and iii) amplification failures in some cases as well. WGPS, a descriptive approach, allowed the identification and localization of divergent genetic loci from various strains of C. burnetii which consisted of deletions, insertions and maybe genomic rearrangements. It also substantiates the role played by the IS1111 element in the genomic plasticity of C. burnetii. We believe that this approach could be combined with new sequencing technologies, as a selective/directed sequencing approach, particularly when repeated sequences are present in the analysed genomes. PMID:26315064

  20. Coxiella burnetii infection of a bovine jugular vein conduit in a child.

    PubMed

    Tasher, Diana; Stein, Michal; Raucher-Sternfeld, Alona; Somekh, Eli

    2012-06-01

    We report a case of an 11-year-old girl with Coxiella burnetii infection of a bovine jugular vein conduit which is an extremely rare manifestation of Q fever. The role of surgery in the management of C. burnetii endovascular infection and the use of serology are discussed. PMID:22349674

  1. Draft Genome Sequences of Six Ruminant Coxiella burnetii Isolates of European Origin

    PubMed Central

    Ellis, Richard J.; Adam, Gilbert; Prigent, Myriam; Angen, Øystein; Aspán, Anna; Thiéry, Richard; Rousset, Elodie

    2014-01-01

    Coxiella burnetii is responsible for Q fever, a worldwide zoonosis attributed to the inhalation of aerosols contaminated by livestock birth products. Six draft genome sequences of European C. burnetii isolates from ruminants are presented here. The availability of these genomes will help in understanding the potential host specificity and pathogenicity and in identifying pertinent markers for surveillance and tracing. PMID:24831135

  2. Genotyping and Axenic Growth of Coxiella burnetii Isolates Found in the United States Environment.

    PubMed

    Kersh, Gilbert J; Priestley, Rachael A; Hornstra, Heidie M; Self, Joshua S; Fitzpatrick, Kelly A; Biggerstaff, Brad J; Keim, Paul; Pearson, Talima; Massung, Robert F

    2016-09-01

    Coxiella burnetii is a gram-negative bacterium that is the etiologic agent of the zoonotic disease Q fever. Common reservoirs of C. burnetii include sheep, goats, and cattle. These animals shed C. burnetii into the environment, and humans are infected by inhalation of aerosols. A survey of 1622 environmental samples taken across the United States in 2006-2008 found that 23.8% of the samples contained C. burnetii DNA. To identify the strains circulating in the U.S. environment, DNA from these environmental samples was genotyped using an SNP-based approach to derive sequence types (ST) that are also compatible with multispacer sequence typing methods. Three different sequence types were observed in 31 samples taken from 19 locations. ST8 was associated with goats and ST20 with dairy cattle. ST16/26 was detected in locations with exposure to various animals and also in locations with no direct animal contact. Viable isolates were obtained for all three sequence types, but only the ST20 and ST16/26 isolates grew in acidified citrate cysteine medium (ACCM)-2 axenic media. Examination of a variety of isolates with different sequence types showed that ST8 and closely related isolates did not grow in ACCM-2. These results suggest that a limited number of C. burnetii sequence types are circulating in the U.S. environment and these strains have close associations with specific reservoir species. Growth in ACCM-2 may not be suitable for isolation of many C. burnetii strains. PMID:27304166

  3. Prevalence of Coxiella burnetii in western grey kangaroos (Macropus fuliginosus) in Western Australia.

    PubMed

    Potter, Abbey S; Banazis, Michael J; Yang, Rongchang; Reid, Simon A; Fenwick, Stan G

    2011-10-01

    We investigated the role of the western grey kangaroo (Macropus fuliginosus) in the maintenance and transmission of Coxiella burnetii in Western Australia. Sera from 1,017 kangaroos were tested using an indirect enzyme-linked immunosorbent assay (ELISA) for the presence of C. burnetii antibodies. The overall antibody prevalence across 12 locations throughout mid- to southwestern Western Australia was 24.1% (95% CI: 21.6-26.8). Feces from 990 of the same animals were tested using PCR to identify active shedding of C. burnetii in excreta. Coxiella burnetii DNA was detected in 4.1% (95% CI: 3.1-5.6) of samples. Our results suggest that kangaroos are reservoirs for C. burnetii in Western Australia and may contribute to transmission of the organism to domestic livestock and humans.

  4. Cortactin Is Involved in the Entry of Coxiella burnetii into Non-Phagocytic Cells

    PubMed Central

    Rosales, Eliana M.; Aguilera, Milton O.; Salinas, Romina P.; Carminati, Sergio A.; Colombo, María I.; Martinez-Quiles, Narcisa; Berón, Walter

    2012-01-01

    Background Cortactin is a key regulator of the actin cytoskeleton and is involved in pathogen-host cell interactions. Numerous pathogens exploit the phagocytic process and actin cytoskeleton to infect host cells. Coxiella burnetii, the etiologic agent of Q fever, is internalized by host cells through a molecular mechanism that is poorly understood. Methodology/Principal Finding Here we analyzed the role of different cortactin motifs in the internalization of C. burnetii by non-phagocytic cells. C. burnetii internalization into HeLa cells was significantly reduced when the cells expressed GFP-cortactin W525K, which carries a mutation in the SH3 domain that renders the protein unable to bind targets such as N-WASP. However, internalization was unaffected when the cells expressed the W22A mutant, which has a mutation in the N-terminal acidic region that destroys the protein’s ability to bind and activate Arp2/3. We also determined whether the phosphorylation status of cortactin is important for internalization. Expression of GFP-cortactin 3F, which lacks phosphorylatable tyrosines, significantly increased internalization of C. burnetii, while expression of GFP-cortactin 3D, a phosphotyrosine mimic, did not affect it. In contrast, expression of GFP-cortactin 2A, which lacks phosphorylatable serines, inhibited C. burnetii internalization, while expression of GFP-cortactin SD, a phosphoserine mimic, did not affect it. Interestingly, inhibitors of Src kinase and the MEK-ERK kinase pathway blocked internalization. In fact, both kinases reached maximal activity at 15 min of C. burnetii infection, after which activity decreased to basal levels. Despite the decrease in kinase activity, cortactin phosphorylation at Tyr421 reached a peak at 1 h of infection. Conclusions/Significance Our results suggest that the SH3 domain of cortactin is implicated in C. burnetii entry into HeLa cells. Furthermore, cortactin phosphorylation at serine and dephosphorylation at tyrosine favor C

  5. Evidence of Coxiella burnetii in Punjab province, Pakistan.

    PubMed

    Shabbir, Muhammad Zubair; Akram, Sidra; Hassan, Zia Ul; Hanif, Kashif; Rabbani, Masood; Muhammad, Javed; Chaudhary, Muhammad Hamid; Abbas, Tariq; Ghori, Muhammad Taslim; Rashid, Haroon; Jamil, Tariq; Islam, Zia-Ul-; Rasool, Haisem; Bano, Asghari; Ahmad, Arfan; Ali, Muhammad Asad; Yaqub, Tahir; McVey, Walt; Jayarao, Bhushan M

    2016-11-01

    Coxiella burnetii causes query (Q) fever, an important zoonotic disease with worldwide significance. The role of environment in the ecology of C. burnetti, and its influence on seroconversion in animals has not been elucidated in Pakistan. We carried out a cross-sectional study in Punjab province to (1) determine the prevalence and distribution of C. burnetii in soil using an ISIIII gene-based real time-polymerase chain reaction (RT-PCR) assay, (2) analyze association between the occurrence of C. burnetii in soil and its predictors i.e. soil characteristics (macro- and micro-nutrients) and several likely risk factors including the seroconversion in small ruminants at places where its genome had or had not been detected, and (3) predict homology and genetic diversity of the identified strains using sequences originated from different hosts worldwide. A total of 2425 soil samples from nine districts of Punjab province were processed. C. burnetii DNA was detected in 47 samples (1.94%, 95% CI: ±0.55) originating from 35 villages of studied districts (7.22%, 95% CI: ±2.30). The highest prevalence was found in Attock (7.11%, 95% CI: ±3.36), followed by Lahore (4.83%, 95% CI: ±3.49), Sahiwal (4.70%, 95% CI: ±2.6), Dera Ghazi Khan (2.33%, 95% CI: ±2.02), Faisalabad (1.35%, 95% CI: ±1.18) and Sheikhupura (0.68%, 95% CI: ±0.94). The odds of detecting bacterial DNA in soil was increased with a unit increase in organic matter [2.511 (95% CI: 1.453-4.340), p=0.001] and sodium [1.013 (95% CI: 1.005-1.022), p=0.001], whereas, calcium [0.984 (95% CI: 0.975-0.994), p=0.002] and potassium [0.994 (95% CI: 0.990-0.999), p=0.011] had protective effect where a unit increase in each analyte decreased odds for its occurrence by 1.0% approximately. Likewise, for categorical variables (risk factors), the odds of detecting C. burnetii were higher at locations >500m away from a main road [1.95 (95% CI: 1.06-3.78), p=0.04]. The enzyme-linked immunosorbent assay (ELISA

  6. Identification of Coxiella burnetii Type IV Secretion Substrates Required for Intracellular Replication and Coxiella-Containing Vacuole Formation

    PubMed Central

    Weber, Mary M.; Chen, Chen; Rowin, Kristina; Mertens, Katja; Galvan, Gloria; Zhi, Hui; Dealing, Christopher M.; Roman, Victor A.; Banga, Simran; Tan, Yunhao; Luo, Zhao-Qing

    2013-01-01

    Coxiella burnetii, the etiological agent of acute and chronic Q fever in humans, is a naturally intracellular pathogen that directs the formation of an acidic Coxiella-containing vacuole (CCV) derived from the host lysosomal network. Central to its pathogenesis is a specialized type IVB secretion system (T4SS) that delivers effectors essential for intracellular replication and CCV formation. Using a bioinformatics-guided approach, 234 T4SS candidate substrates were identified. Expression of each candidate as a TEM-1 β-lactamase fusion protein led to the identification of 53 substrates that were translocated in a Dot/Icm-dependent manner. Ectopic expression in HeLa cells revealed that these substrates trafficked to distinct subcellular sites, including the endoplasmic reticulum, mitochondrion, and nucleus. Expression in Saccharomyces cerevisiae identified several substrates that were capable of interfering with yeast growth, suggesting that these substrates target crucial host processes. To determine if any of these T4SS substrates are necessary for intracellular replication, we isolated 20 clonal T4SS substrate mutants using the Himar1 transposon and transposase. Among these, 10 mutants exhibited defects in intracellular growth and CCV formation in HeLa and J774A.1 cells but displayed normal growth in bacteriological medium. Collectively, these results indicate that C. burnetii encodes a large repertoire of T4SS substrates that play integral roles in host cell subversion and CCV formation and suggest less redundancy in effector function than has been found in the comparative Legionella Dot/Icm model. PMID:23813730

  7. The Development of Lyophilized Loop-mediated Isothermal Amplification Reagents for the Detection of Coxiella burnetii.

    PubMed

    Chen, Hua-Wei; Ching, Wei-Mei

    2016-04-18

    Coxiella burnetii, the agent causing Q fever, is an obligate intracellular bacterium. PCR based diagnostic assays have been developed for detecting C. burnetii DNA in cell cultures and clinical samples. PCR requires specialized equipment and extensive end user training, and therefore, it is not suitable for routine work especially in a resource-constrained area. We have developed a loop-mediated isothermal amplification (LAMP) assay to detect the presence of C. burnetii in patient samples. This method is performed at a single temperature around 60 °C in a water bath or heating block. The sensitivity of this LAMP assay is very similar to PCR with a detection limit of about 25 copies per reaction. This report describes the preparation of the reaction using lyophilized reagents and visualization of results using hydroxynaphthol blue (HNB) or a UV lamp with fluorescent intercalating dye in the reaction. The LAMP reagents were lyophilized and stored at room temperature (RT) for one month without loss of detection sensitivity. This LAMP assay is particularly robust because the reaction mixture preparation does not involve complex steps. This method is ideal for use in resource-limited settings where Q fever is endemic.

  8. The Development of Lyophilized Loop-mediated Isothermal Amplification Reagents for the Detection of Coxiella burnetii.

    PubMed

    Chen, Hua-Wei; Ching, Wei-Mei

    2016-01-01

    Coxiella burnetii, the agent causing Q fever, is an obligate intracellular bacterium. PCR based diagnostic assays have been developed for detecting C. burnetii DNA in cell cultures and clinical samples. PCR requires specialized equipment and extensive end user training, and therefore, it is not suitable for routine work especially in a resource-constrained area. We have developed a loop-mediated isothermal amplification (LAMP) assay to detect the presence of C. burnetii in patient samples. This method is performed at a single temperature around 60 °C in a water bath or heating block. The sensitivity of this LAMP assay is very similar to PCR with a detection limit of about 25 copies per reaction. This report describes the preparation of the reaction using lyophilized reagents and visualization of results using hydroxynaphthol blue (HNB) or a UV lamp with fluorescent intercalating dye in the reaction. The LAMP reagents were lyophilized and stored at room temperature (RT) for one month without loss of detection sensitivity. This LAMP assay is particularly robust because the reaction mixture preparation does not involve complex steps. This method is ideal for use in resource-limited settings where Q fever is endemic. PMID:27167168

  9. The Recent Evolution of a Maternally-Inherited Endosymbiont of Ticks Led to the Emergence of the Q Fever Pathogen, Coxiella burnetii

    PubMed Central

    Duron, Olivier; Noël, Valérie; McCoy, Karen D.; Bonazzi, Matteo; Sidi-Boumedine, Karim; Morel, Olivier; Vavre, Fabrice; Zenner, Lionel; Jourdain, Elsa; Durand, Patrick; Arnathau, Céline; Renaud, François; Trape, Jean-François; Biguezoton, Abel S.; Cremaschi, Julie; Dietrich, Muriel; Léger, Elsa; Appelgren, Anaïs; Dupraz, Marlène; Gómez-Díaz, Elena; Diatta, Georges; Dayo, Guiguigbaza-Kossigan; Adakal, Hassane; Zoungrana, Sébastien; Vial, Laurence; Chevillon, Christine

    2015-01-01

    Q fever is a highly infectious disease with a worldwide distribution. Its causative agent, the intracellular bacterium Coxiella burnetii, infects a variety of vertebrate species, including humans. Its evolutionary origin remains almost entirely unknown and uncertainty persists regarding the identity and lifestyle of its ancestors. A few tick species were recently found to harbor maternally-inherited Coxiella-like organisms engaged in symbiotic interactions, but their relationships to the Q fever pathogen remain unclear. Here, we extensively sampled ticks, identifying new and atypical Coxiella strains from 40 of 58 examined species, and used this data to infer the evolutionary processes leading to the emergence of C. burnetii. Phylogenetic analyses of multi-locus typing and whole-genome sequencing data revealed that Coxiella-like organisms represent an ancient and monophyletic group allied to ticks. Remarkably, all known C. burnetii strains originate within this group and are the descendants of a Coxiella-like progenitor hosted by ticks. Using both colony-reared and field-collected gravid females, we further establish the presence of highly efficient maternal transmission of these Coxiella-like organisms in four examined tick species, a pattern coherent with an endosymbiotic lifestyle. Our laboratory culture assays also showed that these Coxiella-like organisms were not amenable to culture in the vertebrate cell environment, suggesting different metabolic requirements compared to C. burnetii. Altogether, this corpus of data demonstrates that C. burnetii recently evolved from an inherited symbiont of ticks which succeeded in infecting vertebrate cells, likely by the acquisition of novel virulence factors. PMID:25978383

  10. Coxiella burnetii (Q fever) Infection in Farmed Ruminants in Three Northeastern Provinces and Inner Mongolia Autonomous Region, China.

    PubMed

    Cong, Wei; Meng, Qing-Feng; Shan, Xiao-Feng; Sun, Wu-Wen; Kang, Yuan-Huan; Chen, Long; Wang, Wei-Li; Qian, Ai-Dong

    2015-08-01

    Coxiella burnetii is the pathogenic agent of Q fever, a zoonosis that occurs worldwide. In China, the organism infects people and a wide range of wild and farmed animals. However, little is known about C. burnetii infection in farmed ruminants in northeastern China, and there appears to have been no previous study on sika deer. The present study was conducted to determine the seroprevalence of C. burnetii in farmed ruminants in this region of China. A total of 3147 domestic ruminants (784 sheep, 1016 cattle, and 1347 sika deer) were randomly collected for this study. An indirect enzyme-linked immunosorbent assay kit was used to detect the antibodies to C. burnetii. The results showed an overall seroprevalence of 16.7% in domestic ruminants (24.9%, 13.5%, and 12.3% in cattle, sheep, and sika deer, respectively). This is the first report of C. burnetii seroprevalence in sika deer in China. Protective and hygiene measures should be applied in farm management to reduce the risk of exposure of C. burnetii to humans. PMID:26273813

  11. In silico biosynthesis of virenose, a methylated deoxy-sugar unique to Coxiella burnetii lipopolysaccharide

    PubMed Central

    2012-01-01

    Background Coxiella burnetii is Gram-negative bacterium responsible for the zoonosis Q-fever. While it has an obligate intracellular growth habit, it is able to persist for extended periods outside of a host cell and can resist environmental conditions that would be lethal to most prokaryotes. It is these extracellular bacteria that are the infectious stage encountered by eukaryotic hosts. The intracellular form has evolved to grow and replicate within acidified parasitophorous vacuoles. The outer coat of C. burnetii comprises a complex lipopolysaccharide (LPS) component that includes the unique methylated-6-deoxyhexose, virenose. Although potentially important as a biomarker for C. burnetii, the pathway for its biosynthesis remains obscure. Results The 6-deoxyhexoses constitute a large family integral to the LPS of many eubacteria. It is believed that precursors of the methylated-deoxyhexoses traverse common early biosynthetic steps as nucleotide-monosaccharides. As a prelude to a full biosynthetic characterization, we present herein the results from bioinformatics-based, proteomics-supported predictions of the pathway for virenose synthesis. Alternative possibilities are considered which include both GDP-mannose and TDP-glucose as precursors. Conclusion We propose that biosynthesis of the unique C. burnetii biomarker, virenose, involves an early pathway similar to that of other C-3’-methylated deoxysugars which then diverges depending upon the nucleotide-carrier involved. The alternatives yield either the D- or L-enantiomers of virenose. Both pathways require five enzymatic steps, beginning with either glucose-6-phosphate or mannose-6-phosphate. Our in silico results comprise a model for virenose biosynthesis that can be directly tested. Definition of this pathway should facilitate the development of therapeutic agents useful for treatment of Q fever, as well as allowing improvements in the methods for diagnosing this highly infectious disease. PMID:23150954

  12. Serological evidence of Rickettsia and Coxiella burnetii in humans of Buenos Aires, Argentina.

    PubMed

    Cicuttin, Gabriel Leonardo; Degiuseppe, Juan Ignacio; Mamianetti, Andrea; Corin, Marcela Viviana; Linares, María Cielo; De Salvo, María Nazarena; Dohmen, Federico Eugenio Gury

    2015-12-01

    In Buenos Aires city (Argentina), the circulation of these agents has been detected mainly in vectors and animals, few human cases having been described. The aim of our study was to determine the seroprevalence of Rickettsia (spotted fever--SFG--and typhus--TG--groups) and Coxiella burnetii (Q fever agent) in residents of Buenos Aires city. The study involved 99 participants. Rickettsia IgG antibodies against SFG and TG were detected by IFA in 28.3% and 16.2% of serum samples, respectively. SFG titers were mostly 1/64 (53.6%) with a maximum of 1/512 (3.5%) whereas TG titers ranged between 1/64 (62.5%) and 1/256 (6.3%). Only one sample showed a titer of 1/32 for C. burnetii (phases I and II). The circulation of these pathogens in urban areas such as the city of Buenos Aires should be considered by health services, especially at the primary care level. PMID:26616661

  13. Serological evidence of Rickettsia and Coxiella burnetii in humans of Buenos Aires, Argentina.

    PubMed

    Cicuttin, Gabriel Leonardo; Degiuseppe, Juan Ignacio; Mamianetti, Andrea; Corin, Marcela Viviana; Linares, María Cielo; De Salvo, María Nazarena; Dohmen, Federico Eugenio Gury

    2015-12-01

    In Buenos Aires city (Argentina), the circulation of these agents has been detected mainly in vectors and animals, few human cases having been described. The aim of our study was to determine the seroprevalence of Rickettsia (spotted fever--SFG--and typhus--TG--groups) and Coxiella burnetii (Q fever agent) in residents of Buenos Aires city. The study involved 99 participants. Rickettsia IgG antibodies against SFG and TG were detected by IFA in 28.3% and 16.2% of serum samples, respectively. SFG titers were mostly 1/64 (53.6%) with a maximum of 1/512 (3.5%) whereas TG titers ranged between 1/64 (62.5%) and 1/256 (6.3%). Only one sample showed a titer of 1/32 for C. burnetii (phases I and II). The circulation of these pathogens in urban areas such as the city of Buenos Aires should be considered by health services, especially at the primary care level.

  14. Coxiella burnetii infection of marine mammals in the Pacific Northwest, 1997-2010.

    PubMed

    Kersh, Gilbert J; Lambourn, Dyanna M; Raverty, Stephen A; Fitzpatrick, Kelly A; Self, Joshua S; Akmajian, Adrianne M; Jeffries, Steven J; Huggins, Jessica; Drew, Clifton P; Zaki, Sherif R; Massung, Robert F

    2012-01-01

    Q fever is a zoonotic disease caused by the bacterium Coxiella burnetii. Humans are commonly exposed via inhalation of aerosolized bacteria derived from the waste products of domesticated sheep and goats, and particularly from products generated during parturition. However, many other species can be infected with C. burnetii, and the host range and full zoonotic potential of C. burnetii is unknown. Two cases of C. burnetii infection in marine mammal placenta have been reported, but it is not known if this infection is common in marine mammals. To address this issue, placenta samples were collected from Pacific harbor seals (Phoca vitulina richardsi), harbor porpoises (Phocoena phocoena), and Steller sea lions (Eumetopias jubatus). Coxiella burnetii was detected by polymerase chain reaction (PCR) in the placentas of Pacific harbor seals (17/27), harbor porpoises (2/6), and Steller sea lions (1/2) collected in the Pacific Northwest. A serosurvey of 215 Pacific harbor seals sampled in inland and outer coastal areas of the Pacific Northwest showed that 34.0% (73/215) had antibodies against either Phase 1 or Phase 2 C. burnetii. These results suggest that C. burnetii infection is common among marine mammals in this region. PMID:22247392

  15. Molecular investigation of Coxiella burnetii infections in aborted sheep in eastern Turkey

    PubMed Central

    Kılıç, A.; Kalender, H.; Koç, O.; Kılınç, Ü.; Irehan, B.; Berri, M.

    2016-01-01

    Q fever is a zoonotic disease that occurs worldwide and is caused by the obligate intracellular bacterium Coxiella burnetii. The aim of this study was to investigate the presence of C. burnetii infection in aborted sheep in eastern Turkey using PCR. A total of 200 fetuses were collected from aborted sheep belonging to 200 herds in different locations in the eastern part of Turkey. Foetal organ samples such as liver, spleen, lung and stomach were taken and the DNA was purified from two hundred pooled samples. PCR analysis of C. burnetii presence in infected organs was performed, and 4 samples (2%) were found positive. In addition, the pooled organ suspensions were inoculated to embryonated chicken eggs, and PCR analysis of yolk sacs showed C. burnetii DNA in 5 samples (2.5%). This study shows that C. burnetii infection has an important role in sheep abortions in eastern Anatolia region. PMID:27656228

  16. Molecular investigation of Coxiella burnetii infections in aborted sheep in eastern Turkey.

    PubMed

    Kılıç, A; Kalender, H; Koç, O; Kılınç, Ü; Irehan, B; Berri, M

    2016-01-01

    Q fever is a zoonotic disease that occurs worldwide and is caused by the obligate intracellular bacterium Coxiella burnetii. The aim of this study was to investigate the presence of C. burnetii infection in aborted sheep in eastern Turkey using PCR. A total of 200 fetuses were collected from aborted sheep belonging to 200 herds in different locations in the eastern part of Turkey. Foetal organ samples such as liver, spleen, lung and stomach were taken and the DNA was purified from two hundred pooled samples. PCR analysis of C. burnetii presence in infected organs was performed, and 4 samples (2%) were found positive. In addition, the pooled organ suspensions were inoculated to embryonated chicken eggs, and PCR analysis of yolk sacs showed C. burnetii DNA in 5 samples (2.5%). This study shows that C. burnetii infection has an important role in sheep abortions in eastern Anatolia region. PMID:27656228

  17. In silico biosynthesis of virenose, a methylated deoxy-sugar unique to Coxiella burnetii lipopolysaccharide

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Coxiella burnetii is Gram-negative bacterium responsible for the zoonosis Q-fever. While it has an obligate intracellulargrowth habit, it is able to persist for extended periods outside of a host cell and can resist environmental conditions that would be lethal to most prokaryotes. It is...

  18. Bartonella spp. and Coxiella burnetii Associated with Community-Acquired, Culture-Negative Endocarditis, Brazil.

    PubMed

    Siciliano, Rinaldo Focaccia; Castelli, Jussara Bianchi; Mansur, Alfredo Jose; Pereira dos Santos, Fabiana; Colombo, Silvia; do Nascimento, Elvira Mendes; Paddock, Christopher D; Brasil, Roosecelis Araújo; Velho, Paulo Eduardo Neves Ferreira; Drummond, Marina Rovani; Grinberg, Max; Strabelli, Tania Mara Varejao

    2015-08-01

    We evaluated culture-negative, community-acquired endocarditis by using indirect immunofluorescent assays and molecular analyses for Bartonella spp. and Coxiella burnetii and found a prevalence of 19.6% and 7.8%, respectively. Our findings reinforce the need to study these organisms in patients with culture-negative, community-acquired endocarditis, especially B. henselae in cat owners.

  19. Coxiella burnetii infection of a Steller sea lion (Eumetopias jubatus) found in Washington State.

    PubMed

    Kersh, Gilbert J; Lambourn, Dyanna M; Self, Joshua S; Akmajian, Adrianne M; Stanton, James B; Baszler, Timothy V; Raverty, Stephen A; Massung, Robert F

    2010-09-01

    A pregnant sea lion stranded in the State of Washington was found to have placentitis caused by a unique strain of Coxiella burnetii. This is the first description of coxiellosis in a sea lion and suggests that exposure to sea lions may be a risk factor for contracting Q fever. PMID:20592144

  20. Coxiella burnetii Infection of a Steller Sea Lion (Eumetopias jubatus) Found in Washington State ▿

    PubMed Central

    Kersh, Gilbert J.; Lambourn, Dyanna M.; Self, Joshua S.; Akmajian, Adrianne M.; Stanton, James B.; Baszler, Timothy V.; Raverty, Stephen A.; Massung, Robert F.

    2010-01-01

    A pregnant sea lion stranded in the State of Washington was found to have placentitis caused by a unique strain of Coxiella burnetii. This is the first description of coxiellosis in a sea lion and suggests that exposure to sea lions may be a risk factor for contracting Q fever. PMID:20592144

  1. Secondary Aortoesophageal Fistula Associated With Aneurysmal Graft Infection by Coxiella burnetii.

    PubMed

    Okwara, Chinemerem John; Petrasek, Jan; Gibson, Maeghan; Burstein, Ezra

    2016-04-01

    Aortoesophageal fistula is a rare and serious condition that carries a high mortality rate. We present a case of overt gastrointestinal bleeding from an aortoesophageal fistula in a patient with chronic infection of an endovascular prosthesis with Coxiella burnetii. PMID:27144194

  2. Secondary Aortoesophageal Fistula Associated With Aneurysmal Graft Infection by Coxiella burnetii

    PubMed Central

    Petrasek, Jan; Gibson, Maeghan; Burstein, Ezra

    2016-01-01

    Aortoesophageal fistula is a rare and serious condition that carries a high mortality rate. We present a case of overt gastrointestinal bleeding from an aortoesophageal fistula in a patient with chronic infection of an endovascular prosthesis with Coxiella burnetii. PMID:27144194

  3. Unique clone of Coxiella burnetii causing severe Q fever, French Guiana.

    PubMed

    Mahamat, Aba; Edouard, Sophie; Demar, Magalie; Abboud, Philippe; Patrice, Jean-Yves; La Scola, Bernard; Okandze, Antoine; Djossou, Félix; Raoult, Didier

    2013-07-01

    Acute Q fever is an emergent and severe disease in French Guiana. We obtained 5 Coxiella burnetii isolates from samples of patients from Cayenne and found an epidemic clone circulating in Cayenne. This clone has caused pneumonia and endocarditis and seems to be more virulent than previously described strains.

  4. The contribution of proteomics towards deciphering the enigma of Coxiella burnetii.

    PubMed

    Vranakis, Iosif; Papadioti, Anastasia; Tselentis, Yannis; Psaroulaki, Anna; Tsiotis, Georgios

    2013-01-01

    Coxiella burnetii, the causative agent of Q fever, is an intracellular bacterium and a potential weapon for bioterrorism. The widespread throughout the world, zoonosis is manifested clinically as a self-limited febrile illness, as pneumonia (acute Q fever) or as a chronic illness with endocarditis being its major complication. The recent Netherlands Q fever outbreak has driven the bacterium from a relatively cryptic, underappreciated, "niche" microorganism on the sideline of bacteriology, to one of possibly great impact on public health. Advances in the study of this microorganism proceeded slowly, primarily due to the, until recently, obligatory intracellular nature of the pathogen that in its virulent phase I must be manipulated under biosafety level-3 conditions. Proteomic studies, in particular, have generated a vast amount of information concerning several aspects of the bacterium such as virulence factors, detection/diagnostic and immunogenic biomarkers, inter-/intraspecies variation, resistance to antibiotics, and secreted effector proteins with significant clinical impact. The phenomenon observed following the genomics era, that of generation and accumulation of huge amount of data that ultimately end up unexploited on several databases, begins to emerge in the proteomics field as well. This review will focus on the advances in the field of C. burnetii proteomics through MS, attempting in parallel to utilize some of the proteomics findings by suggesting future directions for the improvement of Q fever diagnosis and therapy. PMID:23255407

  5. Multiple strains of Coxiella burnetii are present in the environment of St. Paul Island, Alaska.

    PubMed

    Duncan, C; Savage, K; Williams, M; Dickerson, B; Kondas, A V; Fitzpatrick, K A; Guerrero, J L; Spraker, T; Kersh, G J

    2013-08-01

    In 2010, Coxiella burnetii was identified at a high prevalence in the placentas of Northern fur seals (Callorhinus ursinus) collected at a single rookery on St. Paul Island Alaska; an area of the United States where the agent was not known to be present. As contamination was hypothesized as a potential cause of false positives, but nothing was known about environmental C. burnetii in the region, an environmental survey was conducted to look for the prevalence and distribution of the organism on the island. While environmental prevalence was low, two strains of the organism were identified using PCR targeting the COM1 and IS1111 genes. The two strains are consistent with the organism that has been increasingly identified in marine mammals as well as a strain type more commonly found in terrestrial environments and associated with disease in humans and terrestrial animals. Further work is needed to elucidate information regarding the ecology of this organism in this region, particularly in association with the coastal environment. PMID:22747976

  6. Multiple strains of Coxiella burnetii are present in the environment of St. Paul Island, Alaska

    PubMed Central

    Duncan, Colleen; Savage, Kate; Williams, Michael; Dickerson, Bobette; Kondas, Ashley V.; Fitzpatrick, Kelly A.; Guerrero, Juan Leon; Spraker, Terry; Kersh, Gilbert J.

    2015-01-01

    Summary In 2010, Coxiella burnetii was identified at a high prevalence in the placentas of Northern fur seals (Callorhinus ursinus) collected at a single rookery on St. Paul Island Alaska; an area of the United States where the agent was not known to be present. As contamination was hypothesized as a potential cause of false positives, but nothing was known about environmental C. burnetii in the region, an environmental survey was conducted to look for the prevalence and distribution of the organism on the island. While environmental prevalence was low, two strains of the organism were identified using PCR targeting the COM1 and IS1111 genes. The two strains are consistent with the organism that has been increasingly identified in marine mammals as well as a strain type more commonly found in terrestrial environments and associated with disease in humans and terrestrial animals. Further work is needed to elucidate information regarding the ecology of this organism in this region, particularly in association with the coastal environment. PMID:22747976

  7. Neutrophils play an important role in protective immunity against Coxiella burnetii infection.

    PubMed

    Elliott, Alexandra; Schoenlaub, Laura; Freches, Danielle; Mitchell, William; Zhang, Guoquan

    2015-08-01

    Coxiella burnetii is an obligate intracellular Gram-negative bacterium that causes the zoonotic disease Q fever. Although Q fever is mainly transmitted by aerosol infection, study of the immune responses in the lung following pulmonary C. burnetii infection is lacking. Neutrophils are considered the first immune cell to migrate into the lung and play an important role in host defense against aerosol infection with microbial pathogens. However, the role of neutrophils in the host defense against C. burnetii infection remains unclear. To determine the role of neutrophils in protective immunity against C. burnetii infection, the RB6-8C5 antibody was used to deplete neutrophils in mice before intranasal infection with C. burnetii. The results indicated that neutrophil-depleted mice developed more severe disease than their wild-type counterparts, suggesting that neutrophils play an important role in host defense against C. burnetii pulmonary infection. We also found that neither CXC chemokine receptor 2 (CXCR2) nor interleukin-17 (IL-17) receptor (IL-17R) deficiency changed the severity of disease following intranasal C. burnetii challenge, suggesting that keratinocyte-derived chemokine and IL-17 may not play essential roles in the response to C. burnetii infection. However, significantly higher C. burnetii genome copy numbers were detected in the lungs of IL-1R(-/-) mice at 14 days postinfection. This indicates that IL-1 may be important for the clearance of C. burnetii from the lungs following intranasal infection. Our results also suggest that neutrophils are involved in protecting vaccinated mice from C. burnetii challenge-induced disease. This is the first study to demonstrate an important role for neutrophils in protective immunity against C. burnetii infection.

  8. Identification of OmpA, a Coxiella burnetii Protein Involved in Host Cell Invasion, by Multi-Phenotypic High-Content Screening

    PubMed Central

    Martinez, Eric; Cantet, Franck; Fava, Laura; Norville, Isobel; Bonazzi, Matteo

    2014-01-01

    Coxiella burnetii is the agent of the emerging zoonosis Q fever. This pathogen invades phagocytic and non-phagocytic cells and uses a Dot/Icm secretion system to co-opt the endocytic pathway for the biogenesis of an acidic parasitophorous vacuole where Coxiella replicates in large numbers. The study of the cell biology of Coxiella infections has been severely hampered by the obligate intracellular nature of this microbe, and Coxiella factors involved in host/pathogen interactions remain to date largely uncharacterized. Here we focus on the large-scale identification of Coxiella virulence determinants using transposon mutagenesis coupled to high-content multi-phenotypic screening. We have isolated over 3000 Coxiella mutants, 1082 of which have been sequenced, annotated and screened. We have identified bacterial factors that regulate key steps of Coxiella infections: 1) internalization within host cells, 2) vacuole biogenesis/intracellular replication, and 3) protection of infected cells from apoptosis. Among these, we have investigated the role of Dot/Icm core proteins, determined the role of candidate Coxiella Dot/Icm substrates previously identified in silico and identified additional factors that play a relevant role in Coxiella pathogenesis. Importantly, we have identified CBU_1260 (OmpA) as the first Coxiella invasin. Mutations in ompA strongly decreased Coxiella internalization and replication within host cells; OmpA-coated beads adhered to and were internalized by non-phagocytic cells and the ectopic expression of OmpA in E. coli triggered its internalization within cells. Importantly, Coxiella internalization was efficiently inhibited by pretreating host cells with purified OmpA or by incubating Coxiella with a specific anti-OmpA antibody prior to host cell infection, suggesting the presence of a cognate receptor at the surface of host cells. In summary, we have developed multi-phenotypic assays for the study of host/pathogen interactions. By applying our

  9. Coxiella burnetii Effector Proteins That Localize to the Parasitophorous Vacuole Membrane Promote Intracellular Replication

    PubMed Central

    Larson, Charles L.; Beare, Paul A.; Voth, Daniel E.; Howe, Dale; Cockrell, Diane C.; Bastidas, Robert J.; Valdivia, Raphael H.

    2014-01-01

    The intracellular bacterial pathogen Coxiella burnetii directs biogenesis of a parasitophorous vacuole (PV) that acquires host endolysosomal components. Formation of a PV that supports C. burnetii replication requires a Dot/Icm type 4B secretion system (T4BSS) that delivers bacterial effector proteins into the host cell cytosol. Thus, a subset of T4BSS effectors are presumed to direct PV biogenesis. Recently, the PV-localized effector protein CvpA was found to promote C. burnetii intracellular growth and PV expansion. We predict additional C. burnetii effectors localize to the PV membrane and regulate eukaryotic vesicle trafficking events that promote pathogen growth. To identify these vacuolar effector proteins, a list of predicted C. burnetii T4BSS substrates was compiled using bioinformatic criteria, such as the presence of eukaryote-like coiled-coil domains. Adenylate cyclase translocation assays revealed 13 proteins were secreted in a Dot/Icm-dependent fashion by C. burnetii during infection of human THP-1 macrophages. Four of the Dot/Icm substrates, termed Coxiella vacuolar protein B (CvpB), CvpC, CvpD, and CvpE, labeled the PV membrane and LAMP1-positive vesicles when ectopically expressed as fluorescently tagged fusion proteins. C. burnetii ΔcvpB, ΔcvpC, ΔcvpD, and ΔcvpE mutants exhibited significant defects in intracellular replication and PV formation. Genetic complementation of the ΔcvpD and ΔcvpE mutants rescued intracellular growth and PV generation, whereas the growth of C. burnetii ΔcvpB and ΔcvpC was rescued upon cohabitation with wild-type bacteria in a common PV. Collectively, these data indicate C. burnetii encodes multiple effector proteins that target the PV membrane and benefit pathogen replication in human macrophages. PMID:25422265

  10. Genetic variation in TLR10 is not associated with chronic Q fever, despite the inhibitory effect of TLR10 on Coxiella burnetii-induced cytokines in vitro.

    PubMed

    Ammerdorffer, Anne; Stappers, Mark H T; Oosting, Marije; Schoffelen, Teske; Hagenaars, Julia C J P; Bleeker-Rovers, Chantal P; Wegdam-Blans, Marjolijn C; Wever, Peter C; Roest, Hendrik-Jan; van de Vosse, Esther; Netea, Mihai G; Sprong, Tom; Joosten, Leo A B

    2016-01-01

    Coxiella burnetii, the causative agent of Q fever, is recognized by TLR2. TLR10 can act as an inhibitory receptor on TLR2-derived immune responses. Therefore, we investigated the role of TLR10 on C. burnetii-induced cytokine production and assessed whether genetic polymorphisms in TLR10 influences the development of chronic Q fever. HEK293 cells, transfected with TLR2, TLR10 or TLR2/TLR10, and human peripheral blood mononuclear cells (PBMCs) in the presence of anti-TLR10, were stimulated with C. burnetii. In both assays, the absence of TLR10 resulted in increased cytokine responses after C. burnetii stimulation. In addition, the effect of single nucleotide polymorphisms (SNPs) in TLR10 was examined in healthy volunteers whose PBMCs were stimulated with C. burnetii Nine Mile or the Dutch outbreak isolate C. burnetii 3262. Individuals bearing SNPs in TLR10 displayed increased cytokine production upon C. burnetii 3262 stimulation. Furthermore, 139 chronic Q fever patients and 220 controls were genotyped for TLR10 N241H, I775V and I369L. None of these polymorphisms were associated with increased susceptibility to chronic Q fever. In conclusion, TLR10 has an inhibitory effect on in vitro cytokine production by C. burnetii, but the presence of TLR10 polymorphisms does not lead to an increased risk of developing chronic Q fever. PMID:26364993

  11. Eight New Genomes and Synthetic Controls Increase the Accessibility of Rapid Melt-MAMA SNP Typing of Coxiella burnetii

    PubMed Central

    Byström, Mona; Forsman, Mats; Frangoulidis, Dimitrios; Janse, Ingmar; Larsson, Pär; Lindgren, Petter; Öhrman, Caroline; van Rotterdam, Bart; Sjödin, Andreas; Myrtennäs, Kerstin

    2014-01-01

    The case rate of Q fever in Europe has increased dramatically in recent years, mainly because of an epidemic in the Netherlands in 2009. Consequently, there is a need for more extensive genetic characterization of the disease agent Coxiella burnetii in order to better understand the epidemiology and spread of this disease. Genome reference data are essential for this purpose, but only thirteen genome sequences are currently available. Current methods for typing C. burnetii are criticized for having problems in comparing results across laboratories, require the use of genomic control DNA, and/or rely on markers in highly variable regions. We developed in this work a method for single nucleotide polymorphism (SNP) typing of C. burnetii isolates and tissue samples based on new assays targeting ten phylogenetically stable synonymous canonical SNPs (canSNPs). These canSNPs represent previously known phylogenetic branches and were here identified from sequence comparisons of twenty-one C. burnetii genomes, eight of which were sequenced in this work. Importantly, synthetic control templates were developed, to make the method useful to laboratories lacking genomic control DNA. An analysis of twenty-one C. burnetii genomes confirmed that the species exhibits high sequence identity. Most of its SNPs (7,493/7,559 shared by >1 genome) follow a clonal inheritance pattern and are therefore stable phylogenetic typing markers. The assays were validated using twenty-six genetically diverse C. burnetii isolates and three tissue samples from small ruminants infected during the epidemic in the Netherlands. Each sample was assigned to a clade. Synthetic controls (vector and PCR amplified) gave identical results compared to the corresponding genomic controls and are viable alternatives to genomic DNA. The results from the described method indicate that it could be useful for cheap and rapid disease source tracking at non-specialized laboratories, which requires accurate genotyping

  12. Eight new genomes and synthetic controls increase the accessibility of rapid melt-MAMA SNP typing of Coxiella burnetii.

    PubMed

    Karlsson, Edvin; Macellaro, Anna; Byström, Mona; Forsman, Mats; Frangoulidis, Dimitrios; Janse, Ingmar; Larsson, Pär; Lindgren, Petter; Ohrman, Caroline; van Rotterdam, Bart; Sjödin, Andreas; Myrtennäs, Kerstin

    2014-01-01

    The case rate of Q fever in Europe has increased dramatically in recent years, mainly because of an epidemic in the Netherlands in 2009. Consequently, there is a need for more extensive genetic characterization of the disease agent Coxiella burnetii in order to better understand the epidemiology and spread of this disease. Genome reference data are essential for this purpose, but only thirteen genome sequences are currently available. Current methods for typing C. burnetii are criticized for having problems in comparing results across laboratories, require the use of genomic control DNA, and/or rely on markers in highly variable regions. We developed in this work a method for single nucleotide polymorphism (SNP) typing of C. burnetii isolates and tissue samples based on new assays targeting ten phylogenetically stable synonymous canonical SNPs (canSNPs). These canSNPs represent previously known phylogenetic branches and were here identified from sequence comparisons of twenty-one C. burnetii genomes, eight of which were sequenced in this work. Importantly, synthetic control templates were developed, to make the method useful to laboratories lacking genomic control DNA. An analysis of twenty-one C. burnetii genomes confirmed that the species exhibits high sequence identity. Most of its SNPs (7,493/7,559 shared by >1 genome) follow a clonal inheritance pattern and are therefore stable phylogenetic typing markers. The assays were validated using twenty-six genetically diverse C. burnetii isolates and three tissue samples from small ruminants infected during the epidemic in the Netherlands. Each sample was assigned to a clade. Synthetic controls (vector and PCR amplified) gave identical results compared to the corresponding genomic controls and are viable alternatives to genomic DNA. The results from the described method indicate that it could be useful for cheap and rapid disease source tracking at non-specialized laboratories, which requires accurate genotyping

  13. Cell-Free Propagation of Coxiella burnetii Does Not Affect Its Relative Virulence

    PubMed Central

    Kuley, Runa; Smith, Hilde E.; Frangoulidis, Dimitrios; Smits, Mari A.; Jan Roest, Hendrik I.; Bossers, Alex

    2015-01-01

    Q fever is caused by the obligate intracellular bacterium Coxiella burnetii. In vitro growth of the bacterium is usually limited to viable eukaryotic host cells imposing experimental constraints for molecular studies, such as the identification and characterisation of major virulence factors. Studies of pathogenicity may benefit from the recent development of an extracellular growth medium for C. burnetii. However, it is crucial to investigate the consistency of the virulence phenotype of strains propagated by the two fundamentally different culturing systems. In the present study, we assessed the viability of C. burnetii and the lipopolysaccaride (LPS) encoding region of the bacteria in both culture systems as indirect but key parameters to the infection potential of C. burnetii. Propidium monoazide (PMA) treatment-based real-time PCR was used for enumeration of viable C. burnetii which were validated by fluorescent infectious focus forming unit counting assays. Furthermore, RNA isolated from C. burnetiipropagated in both the culture systems was examined for LPS-related gene expression. All thus far known LPS-related genes were found to be expressed in early passages in both culturing systems indicating the presence of predominantly the phase I form of C. burnetii. Finally, we used immune-competent mice to provide direct evidence, that the relative virulence of different C. burnetii strains is essentially the same for both axenic and cell-based methods of propagation. PMID:25793981

  14. Coxiella burnetii in northern fur seal (Callorhinus ursinus) placentas from St. Paul Island, Alaska.

    PubMed

    Duncan, Colleen; Kersh, Gilbert J; Spraker, Terry; Patyk, Kelly A; Fitzpatrick, Kelly A; Massung, Robert F; Gelatt, Tom

    2012-03-01

    The decline in the number of northern fur seal (NFS; Callorhinus ursinus) pups on St. Paul Island, Alaska, has led to multidisciplinary research, including investigation into issues of reproductive health and success. Given the recent identification of Coxiella burnetii in the placenta of two other marine mammal species, NFS placentas were collected from Reef rookery on St. Paul Island, Alaska, during the 2010 pupping season, examined histologically, and tested for C. burnetii using polymerase chain reaction (PCR). Of 146 placentas examined, gram-negative intratrophoblastic bacteria that were positive for C. burnetii on immunohistochemistry were observed in 5 (3%) placentas. Placental infection was usually devoid of associated inflammation or significant ancillary pathology. One hundred nine (75%) of the placentas were positive for C. burnetii on PCR. C. burnetii is globally distributed and persists for long periods in the environment, providing ample opportunity for exposure of many species. The significance of this finding for the declining fur seal population, potential human exposure and infection, and impact on other sympatric marine mammal or terrestrial species is unclear; further investigation into the epidemiology of Coxiella in the marine ecosystem is warranted.

  15. Growth of Coxiella burnetii in the Ixodes scapularis-derived IDE8 tick cell line.

    PubMed

    Herrin, Brian; Mahapatra, Saugata; Blouin, Edmour F; Shaw, Edward I

    2011-07-01

    Q fever, a zoonotic disease, is caused by a gram-negative intracellular bacterium, Coxiella burnetii. Although normally transmitted during exposure to infectious aerosols, C. burnetii is also found in arthropod vectors. In the environment, ticks are thought to play a crucial role in bacterial maintenance and transmission by infecting various mammalian species. However, the nature of the pathogen-tick relationship is not well defined. To determine C. burnetii's interactions with a cultured tick cell line, we introduced purified C. burnetii NMII into Ixodes scapularis-derived IDE8 cells and assayed for bacterial presence, replication, gene expression, and subsequent infectivity for mammalian cells. Tick cells were harvested at 24 h, 72 h, 7 days, and 11 days postinfection (PI). C. burnetii uptake and subsequent replication was demonstrated by indirect immunofluorescence assay, electron microscopy, and real-time polymerase chain reaction (PCR). When a genome equivalent multiplicity of infection of 30 was used, 30%-40% of exposed cells were seen to have small, rounded, vacuoles at 72 h PI, whereas at 7 and 11 days PI, 60%-70% of cells contained enlarged vacuoles harboring large numbers of bacteria. Quantitative PCR analysis of total genomic DNA confirmed that C. burnetii genome numbers increased significantly from 24 h to 11 days PI. Expression of C. burnetii type four secretion system homologs at 7 days PI was demonstrated by reverse transcriptase PCR. Finally, indirect immunofluorescence assay demonstrated that C. burnetii propagated within IDE8 cells were infectious for mammalian cells. These studies demonstrate the utility of cultured tick cell lines as a model to investigate C. burnetii's molecular interactions with its arthropod vectors.

  16. Coxiella burnetii associated reproductive disorders in domestic animals-a critical review

    PubMed Central

    2013-01-01

    The bacterium Coxiella burnetii has been detected in the fetal membranes, birth fluids and vaginal mucus, as well as in the milk and other excretions of several domestic mammals. The finding of C. burnetii in association with abortion, parturition and in the postpartum period has led to the hypothesis that C. burnetii causes a range of reproductive diseases. This review critically evaluates the scientific basis for this hypothesis in domestic mammals. The review demonstrates a solid evidence for the association between C. burnetii infection and sporadic cases of abortion, premature delivery, stillbirth and weak offspring in cattle, sheep and goats. C. burnetii induced in-herd epidemics of this complete expression of reproductive failure have been reported for sheep and goats, but not for cattle. The single entities occur only as part of the complex and not as single events such as generally increased stillbirth rate. Studies show that C. burnetii initially infects the placenta and that subsequent spread to the fetus may occur either haematogenous or by the amniotic-oral route. The consequences for the equine, porcine, canine and feline conceptus remains to the elucidated but that infection of the conceptus may occur is documented for most species. There is no solid evidence to support a hypothesis of C. burnetii causing disorders such as subfertility, endometritis/metritis, or retained fetal membranes in any kind of domestic animal species. There is a strong need to validate non-pathology based methods such as polymerase chain reaction for their use in diagnostic and research in relation to establishing C. burnetii as the cause of abortion and to adapt an appropriate study design and include adequate control animals when linking epidemiological findings to C. burnetii or when evaluating effects of vaccination in production herds. PMID:23419216

  17. Development of an Ex Vivo Tissue Platform To Study the Human Lung Response to Coxiella burnetii

    PubMed Central

    Graham, Joseph G.; Winchell, Caylin G.; Kurten, Richard C.

    2016-01-01

    Coxiella burnetii is an intracellular bacterial pathogen that causes human Q fever, an acute debilitating flu-like illness that can also present as chronic endocarditis. Disease typically occurs following inhalation of contaminated aerosols, resulting in an initial pulmonary infection. In human cells, C. burnetii generates a replication niche termed the parasitophorous vacuole (PV) by directing fusion with autophagosomes and lysosomes. C. burnetii requires this lysosomal environment for replication and uses a Dot/Icm type IV secretion system to generate the large PV. However, we do not understand how C. burnetii evades the intracellular immune surveillance that triggers an inflammatory response. We recently characterized human alveolar macrophage (hAM) infection in vitro and found that avirulent C. burnetii triggers sustained interleukin-1β (IL-1β) production. Here, we evaluated infection of ex vivo human lung tissue, defining a valuable approach for characterizing C. burnetii interactions with a human host. Within whole lung tissue, C. burnetii preferentially replicated in hAMs. Additionally, IL-1β production correlated with formation of an apoptosis-associated speck-like protein containing a caspase activation and recruitment domain (ASC)-dependent inflammasome in response to infection. We also assessed potential activation of a human-specific noncanonical inflammasome and found that caspase-4 and caspase-5 are processed during infection. Interestingly, although inflammasome activation is closely linked to pyroptosis, lytic cell death did not occur following C. burnetii-triggered inflammasome activation, indicating an atypical response after intracellular detection. Together, these studies provide a novel platform for studying the human innate immune response to C. burnetii. PMID:26902725

  18. A survey of Western Australian sheep, cattle and kangaroos to determine the prevalence of Coxiella burnetii.

    PubMed

    Banazis, Michael Janis; Bestall, Abbey Simone; Reid, Simon Andrew; Fenwick, Stan Gordon

    2010-07-14

    The objective of this study was to investigate the prevalence of Coxiella burnetii in two domestic ruminant species (cattle and sheep) and the western grey kangaroo (Macropus fuliginosus) in Western Australia (WA). The IDEXX CHEKiT Q Fever ELISA and CFT were used to test sera from 50 sheep and 329 head of cattle for anti-C. burnetii antibodies and 343 kangaroo sera were tested using an indirect ELISA developed specifically for this study. Faecal or urine samples collected from the same animals were tested with two PCR assays to identify active shedding of C. burnetii in excreta. Only two of the 379 ruminant sera had detectable levels of anti-C. burnetii antibodies according to the ELISA while the CFT did not detect any positive samples. In contrast 115 of the 343 western grey kangaroo serum samples were positive when tested with the antibody-ELISA. The first qPCR assay, targeting the IS1111a element, identified 41 of 379 ruminant and 42 of 343 kangaroo DNA samples as positive for C. burnetii DNA. The second qPCR, targeting the JB153-3 gene, identified nine C. burnetii DNA-positive ruminant samples and six positive kangaroo samples. Sequence comparisons showed high degrees of identity with C. burnetii. Isolation of C. burnetii from faeces was also attempted but was not successful. From the results presented here it appears that domestic ruminants may not be the most significant reservoir of C. burnetii in WA and that kangaroos may pose a significant threat for zoonotic transfer of this pathogen.

  19. Type I Interferon Counters or Promotes Coxiella burnetii Replication Dependent on Tissue.

    PubMed

    Hedges, Jodi F; Robison, Amanda; Kimmel, Emily; Christensen, Kelly; Lucas, Erin; Ramstead, Andrew; Jutila, Mark A

    2016-06-01

    Coxiella burnetii is an intracellular pathogen and the cause of Q fever. Gamma interferon (IFN-γ) is critical for host protection from infection, but a role for type I IFN in C. burnetii infection has not been determined. Type I IFN supports host protection from a related pathogen, Legionella pneumophila, and we hypothesized that it would be similarly protective in C. burnetii infection. In contrast to our prediction, IFN-α receptor-deficient (IFNAR(-/-)) mice were protected from C. burnetii-induced infection. Therefore, the role of type I IFN in C. burnetii infection was distinct from that in L. pneumophila Mice treated with a double-stranded-RNA mimetic were protected from C. burnetii-induced weight loss through an IFNAR-independent pathway. We next treated mice with recombinant IFN-α (rIFN-α). When rIFN-α was injected by the intraperitoneal route during infection, disease-induced weight loss was exacerbated. Mice that received rIFN-α by this route had dampened interleukin 1β (IL-1β) expression in bronchoalveolar lavage fluids. However, when rIFN-α was delivered to the lung, bacterial replication was decreased in all tissues. Thus, the presence of type I IFN in the lung protected from infection, but when delivered to the periphery, type I IFN enhanced disease, potentially by dampening inflammatory cytokines. To better characterize the capacity for type I IFN induction by C. burnetii, we assessed expression of IFN-β transcripts by human macrophages following stimulation with lipopolysaccharide (LPS) from C. burnetii Understanding innate responses in C. burnetii infection will support the discovery of novel therapies that may be alternative or complementary to the current antibiotic treatment. PMID:27068091

  20. The First Serological Study of Coxiella burnetii among Pregnant Women in Iran

    PubMed Central

    KHAYYAT KHAMENEIE, Maryam; ASADI, Javad; KHALILI, Mohammad; ABIRI, Zeinab

    2016-01-01

    Background: Q fever is a zoonotic disease caused by Coxiella burnetii. There is no information about this disease in pregnant women in Iran. The aim of this study was to investigate the seroprevalence of C. burnetii infection among pregnant women in southwestern (Ahvaz) and northern (Parsabad) Iran and further to comparison its prevalence in normal and abnormal pregnancies. Methods: A total of 400 samples were collected randomly from pregnant women who referred to diagnostic laboratories of Ahvaz and Parsabad in 2014. An indirect ELISA kit, designed in Veterinary Faculty, was used to detect the specific antibodies against phase II humanC. burnetii in serum samples. Results: The overall prevalence of C. burnetii in sera from pregnant women was 29.3% (95% confidence interval (CI): 25–34%). The prevalence of C. burnetii infection was significantly different in Ahvaz and Parsabad with, respectively, 22 (95% CI: 16–28%) and 36.5% (95% CI: 30–43%). Total prevalence of C. burnetii infection in serum was significantly higher in women with abnormal pregnancy history (39.8%) compared with normal pregnancies (23.8%). Furthermore, maternal age had significant association with seropositivity and the prevalence increased with maternal age. This could be due to higher probability of encountering C. burnetii in older women. Conclusion: The present study demonstrated ahigh seroprevalence of C. burnetii infection among pregnant women in Iran for the first time. Seropositivity was associated with adverse pregnancy outcomes and maternal age. The pregnant women who experienced abnormal pregnancy had higher seroprevalence of C. burnetii compared to women with normal pregnancy. PMID:27252922

  1. Inhibition of inflammasome activation by Coxiella burnetii type IV secretion system effector IcaA

    PubMed Central

    Cunha, Larissa D.; Ribeiro, Juliana M.; Fernandes, Talita D.; Massis, Liliana M.; Khoo, Chen Ai; Moffatt, Jennifer H.; Newton, Hayley J.; Roy, Craig R.; Zamboni, Dario S.

    2015-01-01

    Coxiella burnetii is a highly infectious bacterium that promotes its own replication in macrophages by inhibiting several host cell responses. Here, we show that C. burnetii inhibits caspase-1 activation in primary mouse macrophages. By using co-infection experiments, we determine that the infection of macrophages with C. burnetii inhibits the caspase-11-mediated non-canonical activation of the NLRP3 inflammasome induced by subsequent infection with Escherichia coli or Legionella pneumophila. Genetic screening using flagellin mutants of L. pneumophila as a surrogate host, reveals a novel C. burnetii gene (IcaA) involved in the inhibition of caspase activation. Expression of IcaA in L. pneumophila inhibited the caspase-11 activation in macrophages. Moreover, icaA- mutants of C. burnetii failed to suppress the caspase-11-mediated inflammasome activation induced by L. pneumophila. Our data reveal IcaA as a novel C. burnetii effector protein that is secreted by the Dot/Icm type IV secretion system and interferes with the caspase-11-induced, non-canonical activation of the inflammasome. PMID:26687278

  2. Dairy cows with metritis: Coxiella burnetii test results in uterine, blood and bulk milk samples.

    PubMed

    Muskens, J; van Maanen, C; Mars, M H

    2011-01-10

    In cattle, Coxiella burnetii infections are generally asymptomatic but can also be associated with reproductive disorders. Metritis is considered as one of the symptoms of C. burnetii infections, but reliable information is lacking. Therefore, information on the presence of C. burnetii in the uterine content of cows with metritis is important to increase our knowledge on this pathogen. In this study, the uterine content of 45 dairy cows with metritis belonging to 12 herds was tested for C. burnetii with a real-time PCR assay. Only one uterine sample tested PCR (highly) positive, all other samples were PCR negative. The PCR positive cow tested also positive for antibodies. Three other cows from other herds tested antibody positive. The bulk milk (BM) samples of these 12 herds were tested by real-time PCR assay and antibody-ELISA. Six BM samples (50%) were positive in PCR and 10 (83%) were positive in ELISA. Culturing the uterus samples by bacteriology, the most frequently cultured bacteria were arcanobacterium (n=24), E. coli (n=16), other streptococci (n=10), Streptococcus uberis (n=8) and Streptococcus dysgalactiae (n=5). This study indicates that C. burnetii is not an important cause for metritis in dairy herds, although apparently C. burnetii was or had been present in most of these herds.

  3. Long-Term Dynamics of Coxiella burnetii in Farmed Red Deer (Cervus elaphus).

    PubMed

    González-Barrio, David; Fernández-de-Mera, Isabel G; Ortiz, José Antonio; Queirós, João; Ruiz-Fons, Francisco

    2015-01-01

    Several aspects of the dynamics of Coxiella burnetii that are relevant for the implementation of control strategies in ruminant herds with endemic Q fever are unknown. We designed a longitudinal study to monitor the dynamics of exposure to C. burnetii in a red deer herd with endemic infection in order to allow the design of Q fever-specific control approaches. Other relevant aspects of the dynamics of C. burnetii - the effect of herd immune status, age, season, and early infection on exposure, the average half-life of antibodies, the presence and duration of maternal humoral immunity, and the age of first exposure - were analyzed. The dynamics of C. burnetii in deer herds seems to be modulated by host herd and host individual factors and by particular host life-history traits. Red deer females become exposed to C. burnetii at the beginning of their second year since maternal antibodies protect them after birth and during the main pathogen shedding season - at the end of spring-early summer. Infection pressure varies between years, probably associated with herd immunity effects, determining inter-annual variation in the risk of exposure. These results suggest that any strategy applied to control C. burnetii in deer herds should be designed to induce immunity in their first year of life immediately after losing maternal antibodies. The short average life of C. burnetii antibodies suggests that any protection based on humoral immunity would require re-vaccination every 6 months. PMID:26697437

  4. Coxiella burnetii seroprevalence and risk for humans on dairy cattle farms, the Netherlands, 2010-2011.

    PubMed

    Schimmer, B; Schotten, N; van Engelen, E; Hautvast, J L A; Schneeberger, P M; van Duijnhoven, Y T H P

    2014-03-01

    Q fever, caused by Coxiella burnetii, is a recognized occupational infection in persons who have regular contact with ruminants. We determined C. burnetii seroprevalence in residents living or working on dairy cattle farms with ≥50 adult cows and identified risk factors for seropositivity. Serum samples from farm residents, including employees, were tested for C. burnetii IgG and IgM; seroprevalence was 72.1% overall and 87.2%, 54.5%, and 44.2% among farmers, spouses, and children, respectively. Risk factors included farm location in southern region, larger herd size, farm employment, birds in stable, contact with pigs, and indirect contact with rats or mice. Protective factors included automatic milking of cows and fully compliant use of gloves during and around calving. We recommend strengthening general biosecurity measures, such as consistent use of personal protective equipment (e.g., boots, clothing, gloves) by farm staff and avoidance of birds and vermin in stables. PMID:24572637

  5. Serological evidence of Coxiella burnetii exposure in native marsupials and introduced animals in Queensland, Australia.

    PubMed

    Cooper, A; Goullet, M; Mitchell, J; Ketheesan, N; Govan, B

    2012-07-01

    The state of Queensland has the highest incidence of Q fever in Australia. In recent years, there has been an increase in human cases where no contacts with the typical reservoir animals or occupations were reported. The aim of this study was to determine the seroprevalence of Coxiella burnetii in Australian native animals and introduced animals in northern and southeastern Queensland. Australian native marsupials sampled included the brushtail possum (Trichosurus vulpecula) and common northern bandicoot (Isoodon macrourus). Introduced species sampled included dingoes (Canis lupus dingo), cats (Felis catus), foxes (Vulpes vulpes) and pigs (Sus scrofa). Serum samples were tested by ELISA for both phase II and phase I antigens of the organism using an Australian isolate. The serological evidence of C. burnetii infection demonstrated in these species has public health implications due to their increasing movement into residential areas in regional Queensland. This study is the first known investigation of C. burnetii seroprevalence in these species in northern Queensland. PMID:21892986

  6. Serological Evidence of Coxiella burnetii Infection in Cattle and Goats in Bangladesh.

    PubMed

    Haider, Najmul; Rahman, Md Shafiqur; Khan, Salah Uddin; Mikolon, Andrea; Osmani, Muzaffor G; Gurley, Emily S; Shanta, Ireen Sultana; Paul, Suman Kumer; Macfarlane-Berry, Laura; Islam, Ariful; Islam, Ausraful; Desmond, James; Epstein, Jonathan H; Priestley, Rachael A; Kersh, Gilbert J; Rahman, Mohammed Ziaur; Daszak, Peter; Luby, Stephen P; Massung, Robert F; Zeidner, Nord

    2015-06-01

    We tested 1149 ruminant sera conveniently collected from three districts of Bangladesh to identify the serological evidence of Coxiella burnetii infection in cattle and goats by enzyme-linked immunosorbent assay. We found that 0.7% (8/1149) of ruminants had detectable immunoglobulin G for C. burnetii: 0.65% (4/620) in cattle and 0.76% (4/529) in goats. A sub-set of ruminant samples was retested and confirmed by immunofluorescence assay (18/112). Although we cannot rule out false-positive reactions, our study suggests the presence of C. burnetii in cattle and goats in Bangladesh. Further studies are required to estimate disease burden at the population level and identify risk factors for Q fever in ruminants in Bangladesh.

  7. Identification of Coxiella burnetii genotypes in Croatia using multi-locus VNTR analysis.

    PubMed

    Račić, Ivana; Spičić, Silvio; Galov, Ana; Duvnjak, Sanja; Zdelar-Tuk, Maja; Vujnović, Anja; Habrun, Boris; Cvetnić, Zeljko

    2014-10-10

    Although Q fever affects humans and animals in Croatia, we are unaware of genotyping studies of Croatian strains of the causative pathogen Coxiella burnetii, which would greatly assist monitoring and control efforts. Here 3261 human and animal samples were screened for C. burnetii DNA by conventional PCR, and 335 (10.3%) were positive. Of these positive samples, 82 were genotyped at 17 loci using the relatively new method of multi-locus variable number tandem repeat analysis (MLVA). We identified 13 C. burnetii genotypes not previously reported anywhere in the world. Two of these 13 genotypes are typical of the continental part of Croatia and share more similarity with genotypes outside Croatia than with genotypes within the country. The remaining 11 novel genotypes are typical of the coastal part of Croatia and show more similarity to one another than to genotypes outside the country. Our findings shed new light on the phylogeny of C. burnetii strains and may help establish MLVA as a standard technique for Coxiella genotyping.

  8. Chronic Q Fever in Alberta: A Case of Coxiella burnetii Mycotic Aneurysm and Concomitant Vertebral Osteomyelitis.

    PubMed

    Stokes, William; Janvier, Jack; Vaughan, Stephen

    2016-01-01

    Chronic Q fever is a potentially life-threatening infection from the intracellular, Gram-negative Coxiella burnetii. It presents most commonly as endocarditis or vascular infection in people with underlying cardiac or vascular disease. We discuss a case of a 67-year-old male with Coxiella burnetii vascular infection of a perirenal abdominal aortic graft. The patient had a history of an abdominal aortic aneurysm (AAA) repair 5 years earlier. He presented with a 12 × 6 × 8 cm perirenal pseudoaneurysm and concomitant L1, L2, and L3 vertebral body discitis. He underwent an open repair which revealed a grossly infected graft perioperatively. Q fever serology revealed phase I serological IgG titer of 1 : 2048 and phase II 1 : 1024 consistent with chronic Q fever. Polymerase chain reaction (PCR) on infected vascular tissue was positive for C. burnetii. The patient was started on doxycycline and hydroxychloroquine with good clinical response and decreasing serological titers. Recognizing chronic Q fever is a difficult task as symptoms are nonspecific, exposure risk is difficult to ascertain, and diagnosis is hidden from conventional microbiological investigations. Its recognition, however, is critical as C. burnetii is inherently resistant to standard empiric therapies used in cardiovascular infections. PMID:27366178

  9. Chronic Q Fever in Alberta: A Case of Coxiella burnetii Mycotic Aneurysm and Concomitant Vertebral Osteomyelitis

    PubMed Central

    Janvier, Jack; Vaughan, Stephen

    2016-01-01

    Chronic Q fever is a potentially life-threatening infection from the intracellular, Gram-negative Coxiella burnetii. It presents most commonly as endocarditis or vascular infection in people with underlying cardiac or vascular disease. We discuss a case of a 67-year-old male with Coxiella burnetii vascular infection of a perirenal abdominal aortic graft. The patient had a history of an abdominal aortic aneurysm (AAA) repair 5 years earlier. He presented with a 12 × 6 × 8 cm perirenal pseudoaneurysm and concomitant L1, L2, and L3 vertebral body discitis. He underwent an open repair which revealed a grossly infected graft perioperatively. Q fever serology revealed phase I serological IgG titer of 1 : 2048 and phase II 1 : 1024 consistent with chronic Q fever. Polymerase chain reaction (PCR) on infected vascular tissue was positive for C. burnetii. The patient was started on doxycycline and hydroxychloroquine with good clinical response and decreasing serological titers. Recognizing chronic Q fever is a difficult task as symptoms are nonspecific, exposure risk is difficult to ascertain, and diagnosis is hidden from conventional microbiological investigations. Its recognition, however, is critical as C. burnetii is inherently resistant to standard empiric therapies used in cardiovascular infections. PMID:27366178

  10. Coxiella burnetii effector CvpB modulates phosphoinositide metabolism for optimal vacuole development.

    PubMed

    Martinez, Eric; Allombert, Julie; Cantet, Franck; Lakhani, Anissa; Yandrapalli, Naresh; Neyret, Aymeric; Norville, Isobel H; Favard, Cyril; Muriaux, Delphine; Bonazzi, Matteo

    2016-06-01

    The Q fever bacterium Coxiella burnetii replicates inside host cells within a large Coxiella-containing vacuole (CCV) whose biogenesis relies on the Dot/Icm-dependent secretion of bacterial effectors. Several membrane trafficking pathways contribute membranes, proteins, and lipids for CCV biogenesis. These include the endocytic and autophagy pathways, which are characterized by phosphatidylinositol 3-phosphate [PI(3)P]-positive membranes. Here we show that the C. burnetii secreted effector Coxiella vacuolar protein B (CvpB) binds PI(3)P and phosphatidylserine (PS) on CCVs and early endosomal compartments and perturbs the activity of the phosphatidylinositol 5-kinase PIKfyve to manipulate PI(3)P metabolism. CvpB association to early endosome triggers vacuolation and clustering, leading to the channeling of large PI(3)P-positive membranes to CCVs for vacuole expansion. At CCVs, CvpB binding to early endosome- and autophagy-derived PI(3)P and the concomitant inhibition of PIKfyve favor the association of the autophagosomal machinery to CCVs for optimal homotypic fusion of the Coxiella-containing compartments. The importance of manipulating PI(3)P metabolism is highlighted by mutations in cvpB resulting in a multivacuolar phenotype, rescuable by gene complementation, indicative of a defect in CCV biogenesis. Using the insect model Galleria mellonella, we demonstrate the in vivo relevance of defective CCV biogenesis by highlighting an attenuated virulence phenotype associated with cvpB mutations. PMID:27226300

  11. Coxiella burnetii and Leishmania mexicana residing within similar parasitophorous vacuoles elicit disparate host responses

    PubMed Central

    Millar, Jess A.; Valdés, Raquel; Kacharia, Fenil R.; Landfear, Scott M.; Cambronne, Eric D.; Raghavan, Rahul

    2015-01-01

    Coxiella burnetii is a bacterium that thrives in an acidic parasitophorous vacuole (PV) derived from lysosomes. Leishmania mexicana, a eukaryote, has also independently evolved to live in a morphologically similar PV. As Coxiella and Leishmania are highly divergent organisms that cause different diseases, we reasoned that their respective infections would likely elicit distinct host responses despite producing phenotypically similar parasite-containing vacuoles. The objective of this study was to investigate, at the molecular level, the macrophage response to each pathogen. Infection of THP-1 (human monocyte/macrophage) cells with Coxiella and Leishmania elicited disparate host responses. At 5 days post-infection, when compared to uninfected cells, 1057 genes were differentially expressed (746 genes up-regulated and 311 genes down-regulated) in C. burnetii infected cells, whereas 698 genes (534 genes up-regulated and 164 genes down-regulated) were differentially expressed in L. mexicana infected cells. Interestingly, of the 1755 differentially expressed genes identified in this study, only 126 genes (~7%) are common to both infections. We also discovered that 1090 genes produced mRNA isoforms at significantly different levels under the two infection conditions, suggesting that alternate proteins encoded by the same gene might have important roles in host response to each infection. Additionally, we detected 257 micro RNAs (miRNAs) that were expressed in THP-1 cells, and identified miRNAs that were specifically expressed during Coxiella or Leishmania infections. Collectively, this study identified host mRNAs and miRNAs that were influenced by Coxiella and/or Leishmania infections, and our data indicate that although their PVs are morphologically similar, Coxiella and Leishmania have evolved different strategies that perturb distinct host processes to create and thrive within their respective intracellular niches. PMID:26300862

  12. Seroprevalence of Coxiella burnetii in domesticated and feral cats in eastern Australia.

    PubMed

    Shapiro, Amanda J; Bosward, Katrina L; Heller, Jane; Norris, Jacqueline M

    2015-05-15

    The seroprevalence of Coxiella burnetii (C. burnetii) in cats in eastern Australia is unknown, and the risk of transmission from cats to humans is undetermined. This study aimed to determine the exposure of cats to C. burnetii in four distinct cat subpopulations. An indirect immunofluoresence assay (IFA) and an Enzyme-linked immunosorbent assay (ELISA) used for detection of anti-C. burnetii antibodies in humans were adapted, verified for use on feline serum, and compared. Cat serum samples (n=712) were tested with IFA from four subpopulations [cattery-confined breeding cats, pet cats, feral cats and shelter cats]. The proportions of seropositive cats were; cattery-confined breeding cats (35/376, 9.3%), pets (2/198, 1%), feral cats (0/50), shelter cats (0/88). The significant variables in C. burnetii seropositivity were cattery-confined breeding cat subpopulation and sterilisation status, with infected cats 17.1 (CI 4.2-70.2; P<0.001) times more likely to be cattery-confined breeding cats and 6.00 (CI 2.13-16.89; P<0.001) times more likely to be entire than sterilised. ELISA was used on 143 of 712 sera tested with IFA, and the Cohen's Kappa coefficient of 0.75 indicated 92.2% agreement between the two assays. These results confirm that Australian cats have been exposed to C. burnetii and that a higher seroprevalence of C. burnetii is seen amongst cattery-confined breeding cats. Cat breeders and veterinary personnel involved in feline reproductive procedures may be at higher risk of exposure to C. burnetii.

  13. Murine Alveolar Macrophages Are Highly Susceptible to Replication of Coxiella burnetii Phase II In Vitro.

    PubMed

    Fernandes, Talita D; Cunha, Larissa D; Ribeiro, Juliana M; Massis, Liliana M; Lima-Junior, Djalma S; Newton, Hayley J; Zamboni, Dario S

    2016-09-01

    Coxiella burnetii is a Gram-negative bacterium that causes Q fever in humans. Q fever is an atypical pneumonia transmitted through inhalation of contaminated aerosols. In mammalian lungs, C. burnetii infects and replicates in several cell types, including alveolar macrophages (AMs). The innate immunity and signaling pathways operating during infection are still poorly understood, in part because of the lack of relevant host cell models for infection in vitro In the study described here, we investigated and characterized the infection of primary murine AMs by C. burnetii phase II in vitro Our data reveal that AMs show a pronounced M2 polarization and are highly permissive to C. burnetii multiplication in vitro Murine AMs present an increased susceptibility to infection in comparison to primary bone marrow-derived macrophages. AMs support more than 2 logs of bacterial replication during 12 days of infection in culture, similar to highly susceptible host cells, such as Vero and THP-1 cells. As a proof of principle that AMs are useful for investigation of C. burnetii replication, we performed experiments with AMs from Nos2(-/-) or Ifng(-/-) mice. In the absence of gamma interferon and nitric oxide synthase 2 (NOS2), AMs were significantly more permissive than wild-type cells. In contrast, AMs from Il4(-/-) mice were more restrictive to C. burnetii replication, supporting the importance of M2 polarization for the permissiveness of AMs to C. burnetii replication. Collectively, our data account for understanding the high susceptibility of alveolar macrophages to bacterial replication and support the use of AMs as a relevant model of C. burnetii growth in primary macrophages. PMID:27297388

  14. Epidemiology of Coxiella burnetii Infection in Africa: A OneHealth Systematic Review

    PubMed Central

    Vanderburg, Sky; Rubach, Matthew P.; Halliday, Jo E. B.; Cleaveland, Sarah; Reddy, Elizabeth A.; Crump, John A.

    2014-01-01

    Background Q fever is a common cause of febrile illness and community-acquired pneumonia in resource-limited settings. Coxiella burnetii, the causative pathogen, is transmitted among varied host species, but the epidemiology of the organism in Africa is poorly understood. We conducted a systematic review of C. burnetii epidemiology in Africa from a “One Health” perspective to synthesize the published data and identify knowledge gaps. Methods/Principal Findings We searched nine databases to identify articles relevant to four key aspects of C. burnetii epidemiology in human and animal populations in Africa: infection prevalence; disease incidence; transmission risk factors; and infection control efforts. We identified 929 unique articles, 100 of which remained after full-text review. Of these, 41 articles describing 51 studies qualified for data extraction. Animal seroprevalence studies revealed infection by C. burnetii (≤13%) among cattle except for studies in Western and Middle Africa (18–55%). Small ruminant seroprevalence ranged from 11–33%. Human seroprevalence was <8% with the exception of studies among children and in Egypt (10–32%). Close contact with camels and rural residence were associated with increased seropositivity among humans. C. burnetii infection has been associated with livestock abortion. In human cohort studies, Q fever accounted for 2–9% of febrile illness hospitalizations and 1–3% of infective endocarditis cases. We found no studies of disease incidence estimates or disease control efforts. Conclusions/Significance C. burnetii infection is detected in humans and in a wide range of animal species across Africa, but seroprevalence varies widely by species and location. Risk factors underlying this variability are poorly understood as is the role of C. burnetii in livestock abortion. Q fever consistently accounts for a notable proportion of undifferentiated human febrile illness and infective endocarditis in cohort studies, but

  15. Comparative sensitivity of four different cell lines for the isolation of Coxiella burnetii.

    PubMed

    Lockhart, Michelle G; Islam, Aminul; Fenwick, Stan G; Graves, Stephen R; Stenos, John

    2012-09-01

    Coxiella burnetii is an obligate intracellular bacterium that causes the disease Q-fever. This is usually diagnosed by serology (immunofluorescence assay) and/or PCR detection of C. burnetii DNA. However, neither of these methods can determine the viability of the bacterium. Four different cell lines were compared for their ability to amplify very low numbers of viable C. burnetii. Two different isolates of C. burnetii were used. For the Henzerling isolate, DH82 (dog macrophage) cells were the most sensitive with an ID (50) (dose required to infect 50% of cell cultures) of 14.6 bacterial copies. For the Arandale isolate, Vero (monkey epithelial) cells were the most sensitive with an ID (50) of less than one bacterium in a 100-μL inoculum. The Vero cell line appeared highly useful as vacuoles could be seen microscopically in unstained infected cells. The findings of this study favour the use of Vero and DH82 tissue culture cell lines for isolation and growth of C. burnetii in vitro. The other cell lines, XTC-2 and L929, were less suitable.

  16. Molecular detection of Coxiella burnetii using an alternative loop-mediated isothermal amplification assay (LAMP).

    PubMed

    Raele, Donato Antonio; Garofolo, Giuliano; Galante, Domenico; Cafiero, Maria Assunta

    2015-01-01

    Q fever, caused by Coxiella burnetii, is a worldwide zoonosis with important consequences for human and animal health. In livestock, the diagnosis, using direct and indirect techniques, is challenging even if to tackle coxiellosis in domesticated animals a rapid diagnosis is crucial. In the recent years, new molecular methods have been developed to overcome these issues. Several polymerase chain reaction (PCR) assays have been studied, but loop mediated isothermal amplification (LAMP) has not been fully developed. This new methodology is emerging due to simplicity and speed in diagnosis of microbial diseases. In this study, we design a new LAMP assay against C. burnetii targeting the com1 gene as an actual alternative to conventional PCR. The assay was specific to C. burnetii reactive with sensitivity comparable to standard PCR. The application of the com1 LAMP on 10 clinical samples from water buffalo, sheep, and goats, previously tested positive, confirmed the presence of C. burnetii. To our knowledge, this study is the first report of LAMP targeting C. burnetii in Europe and the results also suggest that it may be an useful and cost-effective tool for the clinical and epidemiological surveillance of Q Fever.

  17. Emergence of Coxiella burnetii in ruminants on Reunion Island? Prevalence and risk factors.

    PubMed

    Cardinale, Eric; Esnault, Olivier; Beral, Marina; Naze, Florence; Michault, Alain

    2014-08-01

    Q fever is a widespread zoonosis that is caused by Coxiella burnetii (C. burnetii), and ruminants are identified as the main sources of human infections. Some human cases have been described, but very limited information was available about Q fever in ruminants on Reunion Island, a tropical island in the Indian Ocean. A cross-sectional study was undertaken from March 2011 to August 2012 to assess the Q fever prevalence and to identify the major risk factors of C. burnetii infection in ruminants. A total of 516 ruminants (245 cattle, 137 sheep and 134 goats) belonging to 71 farms and localized in different ecosystems of the island were randomly selected. Samples of blood, vaginal mucus and milk were concomitantly collected from females, and a questionnaire was submitted to the farmers. Ticks from positively detected farms were also collected. The overall seropositivity was 11.8% in cattle, 1.4% in sheep and 13.4% in goats. C. burnetii DNA was detected by PCR in 0.81%, 4.4% and 20.1% in cow, sheep and goat vaginal swabs, respectively. C. burnetii shedding in milk was observed in 1% of cows, 0% in sheep and 4.7% in goats. None of the ticks were detected to be positive for C. burnetii. C. burnetii infection increased when the farm was exposed to prevailing winds and when there were no specific precautions for a visitor before entering the farm, and they decreased when a proper quarantine was set up for any introduction of a new ruminant and when the animals returned to the farm at night. MLVA genotyping confirmed the role of these risk factors in infection.

  18. Emergence of Coxiella burnetii in Ruminants on Reunion Island? Prevalence and Risk Factors

    PubMed Central

    Cardinale, Eric; Esnault, Olivier; Beral, Marina; Naze, Florence; Michault, Alain

    2014-01-01

    Q fever is a widespread zoonosis that is caused by Coxiella burnetii (C. burnetii), and ruminants are identified as the main sources of human infections. Some human cases have been described, but very limited information was available about Q fever in ruminants on Reunion Island, a tropical island in the Indian Ocean. A cross-sectional study was undertaken from March 2011 to August 2012 to assess the Q fever prevalence and to identify the major risk factors of C. burnetii infection in ruminants. A total of 516 ruminants (245 cattle, 137 sheep and 134 goats) belonging to 71 farms and localized in different ecosystems of the island were randomly selected. Samples of blood, vaginal mucus and milk were concomitantly collected from females, and a questionnaire was submitted to the farmers. Ticks from positively detected farms were also collected. The overall seropositivity was 11.8% in cattle, 1.4% in sheep and 13.4% in goats. C. burnetii DNA was detected by PCR in 0.81%, 4.4% and 20.1% in cow, sheep and goat vaginal swabs, respectively. C. burnetii shedding in milk was observed in 1% of cows, 0% in sheep and 4.7% in goats. None of the ticks were detected to be positive for C. burnetii. C. burnetii infection increased when the farm was exposed to prevailing winds and when there were no specific precautions for a visitor before entering the farm, and they decreased when a proper quarantine was set up for any introduction of a new ruminant and when the animals returned to the farm at night. MLVA genotyping confirmed the role of these risk factors in infection. PMID:25101780

  19. Emergence of Coxiella burnetii in ruminants on Reunion Island? Prevalence and risk factors.

    PubMed

    Cardinale, Eric; Esnault, Olivier; Beral, Marina; Naze, Florence; Michault, Alain

    2014-08-01

    Q fever is a widespread zoonosis that is caused by Coxiella burnetii (C. burnetii), and ruminants are identified as the main sources of human infections. Some human cases have been described, but very limited information was available about Q fever in ruminants on Reunion Island, a tropical island in the Indian Ocean. A cross-sectional study was undertaken from March 2011 to August 2012 to assess the Q fever prevalence and to identify the major risk factors of C. burnetii infection in ruminants. A total of 516 ruminants (245 cattle, 137 sheep and 134 goats) belonging to 71 farms and localized in different ecosystems of the island were randomly selected. Samples of blood, vaginal mucus and milk were concomitantly collected from females, and a questionnaire was submitted to the farmers. Ticks from positively detected farms were also collected. The overall seropositivity was 11.8% in cattle, 1.4% in sheep and 13.4% in goats. C. burnetii DNA was detected by PCR in 0.81%, 4.4% and 20.1% in cow, sheep and goat vaginal swabs, respectively. C. burnetii shedding in milk was observed in 1% of cows, 0% in sheep and 4.7% in goats. None of the ticks were detected to be positive for C. burnetii. C. burnetii infection increased when the farm was exposed to prevailing winds and when there were no specific precautions for a visitor before entering the farm, and they decreased when a proper quarantine was set up for any introduction of a new ruminant and when the animals returned to the farm at night. MLVA genotyping confirmed the role of these risk factors in infection. PMID:25101780

  20. Coxiella burnetii Infects Primary Bovine Macrophages and Limits Their Host Cell Response.

    PubMed

    Sobotta, Katharina; Hillarius, Kirstin; Mager, Marvin; Kerner, Katharina; Heydel, Carsten; Menge, Christian

    2016-06-01

    Although domestic ruminants have long been recognized as the main source of human Q fever, little is known about the lifestyle that the obligate intracellular Gram-negative bacterium Coxiella burnetii adopts in its animal host. Because macrophages are considered natural target cells of the pathogen, we established primary bovine monocyte-derived macrophages (MDM) as an in vitro infection model to study reservoir host-pathogen interactions at the cellular level. In addition, bovine alveolar macrophages were included to take cell type peculiarities at a host entry site into account. Cell cultures were inoculated with the virulent strain Nine Mile I (NMI; phase I) or the avirulent strain Nine Mile II (NMII; phase II). Macrophages from both sources internalized NMI and NMII. MDM were particularly permissive for NMI internalization, but NMI and NMII replicated with similar kinetics in these cells. MDM responded to inoculation with a general upregulation of Th1-related cytokines such as interleukin-1β (IL-1β), IL-12, and tumor necrosis factor alpha (TNF-α) early on (3 h postinfection). However, inflammatory responses rapidly declined when C. burnetii replication started. C. burnetii infection inhibited translation and release of IL-1β and vastly failed to stimulate increased expression of activation markers, such as CD40, CD80, CD86, and major histocompatibility complex (MHC) molecules. Such capability of limiting proinflammatory responses may help Coxiella to protect itself from clearance by the host immune system. The findings provide the first detailed insight into C. burnetii-macrophage interactions in ruminants and may serve as a basis for assessing the virulence and the host adaptation of C. burnetii strains. PMID:27021246

  1. Seroepidemiologic survey in Thailand of Coxiella burnetii infection in cattle and chickens and presence in ticks attached to dairy cattle.

    PubMed

    Muramatsu, Yasukazu; Usaki, Noriyo; Thongchai, Chalermchaikit; Kramomtong, Indhira; Kriengsak, Poonsuk; Tamura, Yutaka

    2014-09-01

    A seroepidemiologic survey of Coxiella burnetii in cattle and chickens in Thailand was carried out using indirect fluorescent antibody test. Nine of the 130 serum samples from cattle were positive for antibodies against C. burnetii, with antibody titers ranging from 32 to 64. Only one of 113 serum samples from chickens was seropositive, with antibody titer of 16. No C. burnetii-specific DNA was detected using restriction fragment length polymorphism-nested PCR in spleens of cattle and chickens. However, coxiella DNA was detected in two of 102 engorged Rhipicephalus microplus ticks attached to dairy cattle. These results indicated that infestation of C. burnetii among cattle and chickens is considerably low in Thailand. PMID:25417520

  2. Coxiella burnetii Nine Mile II proteins modulate gene expression of monocytic host cells during infection

    PubMed Central

    2010-01-01

    Background Coxiella burnetii is an intracellular bacterial pathogen that causes acute and chronic disease in humans. Bacterial replication occurs within enlarged parasitophorous vacuoles (PV) of eukaryotic cells, the biogenesis and maintenance of which is dependent on C. burnetii protein synthesis. These observations suggest that C. burnetii actively subverts host cell processes, however little is known about the cellular biology mechanisms manipulated by the pathogen during infection. Here, we examined host cell gene expression changes specifically induced by C. burnetii proteins during infection. Results We have identified 36 host cell genes that are specifically regulated when de novo C. burnetii protein synthesis occurs during infection using comparative microarray analysis. Two parallel sets of infected and uninfected THP-1 cells were grown for 48 h followed by the addition of chloramphenicol (CAM) to 10 μg/ml in one set. Total RNA was harvested at 72 hpi from all conditions, and microarrays performed using Phalanx Human OneArray™ slides. A total of 784 (mock treated) and 901 (CAM treated) THP-1 genes were up or down regulated ≥2 fold in the C. burnetii infected vs. uninfected cell sets, respectively. Comparisons between the complementary data sets (using >0 fold), eliminated the common gene expression changes. A stringent comparison (≥2 fold) between the separate microarrays revealed 36 host cell genes modulated by C. burnetii protein synthesis. Ontological analysis of these genes identified the innate immune response, cell death and proliferation, vesicle trafficking and development, lipid homeostasis, and cytoskeletal organization as predominant cellular functions modulated by C. burnetii protein synthesis. Conclusions Collectively, these data indicate that C. burnetii proteins actively regulate the expression of specific host cell genes and pathways. This is in addition to host cell genes that respond to the presence of the pathogen whether or not

  3. Differential interaction with endocytic and exocytic pathways distinguish parasitophorous vacuoles of Coxiella burnetii and Chlamydia trachomatis.

    PubMed

    Heinzen, R A; Scidmore, M A; Rockey, D D; Hackstadt, T

    1996-03-01

    Coxiella burnetii and Chlamydia trachomatis are bacterial obligate intracellular parasites that occupy distinct vacuolar niches within eucaryotic host cells. We have employed immunofluorescence, cytochemistry, fluorescent vital stains, and fluid-phase markers in conjunction with electron, confocal, and conventional microscopy to characterize the vacuolar environments of these pathogens. The acidic nature of the C. burnetii-containing vacuole was confirmed by its acquisition of the acidotropic base acridine orange (AO). The presence of the vacuolar-type (H+) ATPase (V-ATPase) within the Coxiella vacuolar membrane was demonstrated by indirect immunofluorescence, and growth of C. burnetii was inhibited by bafilomycin A1 (Baf A), a specific inhibitor of the V-ATPase. In contrast, AO did not accumulate in C. trachomatis inclusions nor was the V-ATPase found in the inclusion membrane. Moreover, chlamydial growth was not inhibited by Baf A or the lysosomotropic amines methylamine, ammonium chloride, and chloroquine. Vacuoles harboring C. burnetii incorporated the fluorescent fluid- phase markers, fluorescein isothiocyanate-dextran (FITC-dex) and Lucifer yellow (LY), indicating trafficking between that vacuole and the endocytic pathway. Neither FITC-dex nor LY was sequestered by chlamydial inclusions. The late endosomal-prelysosomal marker cation-independent mannose 6-phosphate receptor was not detectable in the vacuolar membranes encompassing either parasite. However, the lysosomal enzymes acid phosphatase and cathepsin D and the lysosomal glycoproteins LAMP-1 and LAMP-2 localized to the C. burnetii vacuole but not the chlamydial vacuole. Interaction of C. trachomatis inclusions with the Golgi-derived vesicles was demonstrated by the transport of sphingomyelin, endogenously synthesized from C6-NBD-ceramide, to the chlamydial inclusion and incorporation into the bacterial cell wall. Similar trafficking of C-NBD-ceramide was not evident in C. burnetii-infected cells

  4. Differential interaction with endocytic and exocytic pathways distinguish parasitophorous vacuoles of Coxiella burnetii and Chlamydia trachomatis.

    PubMed Central

    Heinzen, R A; Scidmore, M A; Rockey, D D; Hackstadt, T

    1996-01-01

    Coxiella burnetii and Chlamydia trachomatis are bacterial obligate intracellular parasites that occupy distinct vacuolar niches within eucaryotic host cells. We have employed immunofluorescence, cytochemistry, fluorescent vital stains, and fluid-phase markers in conjunction with electron, confocal, and conventional microscopy to characterize the vacuolar environments of these pathogens. The acidic nature of the C. burnetii-containing vacuole was confirmed by its acquisition of the acidotropic base acridine orange (AO). The presence of the vacuolar-type (H+) ATPase (V-ATPase) within the Coxiella vacuolar membrane was demonstrated by indirect immunofluorescence, and growth of C. burnetii was inhibited by bafilomycin A1 (Baf A), a specific inhibitor of the V-ATPase. In contrast, AO did not accumulate in C. trachomatis inclusions nor was the V-ATPase found in the inclusion membrane. Moreover, chlamydial growth was not inhibited by Baf A or the lysosomotropic amines methylamine, ammonium chloride, and chloroquine. Vacuoles harboring C. burnetii incorporated the fluorescent fluid- phase markers, fluorescein isothiocyanate-dextran (FITC-dex) and Lucifer yellow (LY), indicating trafficking between that vacuole and the endocytic pathway. Neither FITC-dex nor LY was sequestered by chlamydial inclusions. The late endosomal-prelysosomal marker cation-independent mannose 6-phosphate receptor was not detectable in the vacuolar membranes encompassing either parasite. However, the lysosomal enzymes acid phosphatase and cathepsin D and the lysosomal glycoproteins LAMP-1 and LAMP-2 localized to the C. burnetii vacuole but not the chlamydial vacuole. Interaction of C. trachomatis inclusions with the Golgi-derived vesicles was demonstrated by the transport of sphingomyelin, endogenously synthesized from C6-NBD-ceramide, to the chlamydial inclusion and incorporation into the bacterial cell wall. Similar trafficking of C-NBD-ceramide was not evident in C. burnetii-infected cells

  5. Vasodilator-Stimulated Phosphoprotein Activity Is Required for Coxiella burnetii Growth in Human Macrophages

    PubMed Central

    Colonne, Punsiri M.; Winchell, Caylin G.; Graham, Joseph G.; Onyilagha, Frances I.; MacDonald, Laura J.; Doeppler, Heike R.; Storz, Peter; Kurten, Richard C.; Beare, Paul A.; Voth, Daniel E.

    2016-01-01

    Coxiella burnetii is an intracellular bacterial pathogen that causes human Q fever, an acute flu-like illness that can progress to chronic endocarditis and liver and bone infections. Humans are typically infected by aerosol-mediated transmission, and C. burnetii initially targets alveolar macrophages wherein the pathogen replicates in a phagolysosome-like niche known as the parasitophorous vacuole (PV). C. burnetii manipulates host cAMP-dependent protein kinase (PKA) signaling to promote PV formation, cell survival, and bacterial replication. In this study, we identified the actin regulatory protein vasodilator-stimulated phosphoprotein (VASP) as a PKA substrate that is increasingly phosphorylated at S157 and S239 during C. burnetii infection. Avirulent and virulent C. burnetii triggered increased levels of phosphorylated VASP in macrophage-like THP-1 cells and primary human alveolar macrophages, and this event required the Cα subunit of PKA. VASP phosphorylation also required bacterial protein synthesis and secretion of effector proteins via a type IV secretion system, indicating the pathogen actively triggers prolonged VASP phosphorylation. Optimal PV formation and intracellular bacterial replication required VASP activity, as siRNA-mediated depletion of VASP reduced PV size and bacterial growth. Interestingly, ectopic expression of a phospho-mimetic VASP (S239E) mutant protein prevented optimal PV formation, whereas VASP (S157E) mutant expression had no effect. VASP (S239E) expression also prevented trafficking of bead-containing phagosomes to the PV, indicating proper VASP activity is critical for heterotypic fusion events that control PV expansion in macrophages. Finally, expression of dominant negative VASP (S157A) in C. burnetii-infected cells impaired PV formation, confirming importance of the protein for proper infection. This study provides the first evidence of VASP manipulation by an intravacuolar bacterial pathogen via activation of PKA in human

  6. Long-Term Dynamics of Coxiella burnetii in Farmed Red Deer (Cervus elaphus)

    PubMed Central

    González-Barrio, David; Fernández-de-Mera, Isabel G.; Ortiz, José Antonio; Queirós, João; Ruiz-Fons, Francisco

    2015-01-01

    Several aspects of the dynamics of Coxiella burnetii that are relevant for the implementation of control strategies in ruminant herds with endemic Q fever are unknown. We designed a longitudinal study to monitor the dynamics of exposure to C. burnetii in a red deer herd with endemic infection in order to allow the design of Q fever-specific control approaches. Other relevant aspects of the dynamics of C. burnetii – the effect of herd immune status, age, season, and early infection on exposure, the average half-life of antibodies, the presence and duration of maternal humoral immunity, and the age of first exposure – were analyzed. The dynamics of C. burnetii in deer herds seems to be modulated by host herd and host individual factors and by particular host life-history traits. Red deer females become exposed to C. burnetii at the beginning of their second year since maternal antibodies protect them after birth and during the main pathogen shedding season – at the end of spring-early summer. Infection pressure varies between years, probably associated with herd immunity effects, determining inter-annual variation in the risk of exposure. These results suggest that any strategy applied to control C. burnetii in deer herds should be designed to induce immunity in their first year of life immediately after losing maternal antibodies. The short average life of C. burnetii antibodies suggests that any protection based on humoral immunity would require re-vaccination every 6 months. PMID:26697437

  7. Purification of large quantities of coxiella burnetii rickettsia by density gradient zonal centrifugation.

    PubMed

    Canonico, P G; Van Zwieten, M J; Christmas, W A

    1972-05-01

    The purification of large quantities of inactivated, phase II Coxiella burnetii by isopycnic zonal centrifugation for use as diagnostic antigen and as a vaccine is described. The fractionation of egg yolk sac-derived C. burnetii vaccine resulted in the separation of two distinct populations of organisms, each devoid of microscopically and serologically recognizable components of egg yolk sac. One population of organisms, characterized by an equilibrium density of 1.240, was rod shaped (1.0 by 0.5 mumole) with a thick, densely strained wall and prominent central body. The second population, with an equilibrium density of 1.280, had a coccobacillary shape (approximately 1 mumole in diameter), granular, sometimes fibrillar cytoplasm, thin cellular walls, and lacked a prominent nucleoid.

  8. Coxiella burnetii DNA in goat milk after vaccination with Coxevac(®).

    PubMed

    Hermans, Mirjam H A; Huijsmans, C Ronald J J; Schellekens, Jeroen J A; Savelkoul, Paul H M; Wever, Peter C

    2011-03-24

    Q fever is a zoonotic disease caused by Coxiella burnetii, a species of bacteria that is distributed globally. A large Q fever epidemic is currently spreading throughout the Netherlands with more than 3500 human cases notified from 2007 to 2009. Governmental measures to prevent further spread of the disease imposed in December 2009 included vaccination of all dairy goats and sheep and, in parallel, bulk tank milk testing to identify contaminated goat and sheep farms. When bulk tank milk was found to contain C. burnetii DNA, pregnant ruminants were culled. An important, but unsolved issue in this policy was whether vaccine-derived C. burnetii DNA is excreted in milk after vaccination. Using real time PCR and single nucleotide polymorphism (SNP) genotyping techniques, we show here that within hours and up to 9 days after vaccination with Coxevac(®), vaccine-derived C. burnetii DNA can be detected in the milk of dairy goats. This is the first report describing DNAlactia of vaccine-derived DNA after vaccination with a completely inactivated vaccine. This finding had implications for the Dutch policy to combat the Q fever epidemic. A 2-week interval was introduced between vaccination and bulk tank milk testing to identify infected farms.

  9. [Infrarenal aortic pseudo-aneurism due to Coxiella burnetii].

    PubMed

    Paumier, A; Penard, J; Maugin, E; Enon, B; Picquet, J

    2007-12-01

    Peripheral vascular expressions of Coxiella burnetti Q fever are not well known. Endocarditis with negative blood culture is the most frequent clinical presentation of chronic Q fever. To date, very few cases of aneurisms or vascular grafts infections have been described. We report the case of a 54-year-old man who presented an infrarenal abdominal aorta infection, leading to a giant pseudo aneurismal formation. Blood serology and polymerase chain reaction amplification identified C. burnetti from the aortic thrombus after pseudo aneurism surgery. The treatment associated infrarenal abdominal aorta repair using a cryopreserved aorta allograft, and long-term antibiotic therapy. PMID:17851006

  10. Treatment of an Abdominal Aortic Aneurysm Infected by Coxiella Burnetii Using a Cryopreserved Allograft.

    PubMed

    Jayet, Jérémie; Raux, Maxime; Allaire, Eric; Desgranges, Pascal; Cochennec, Frédéric

    2016-05-01

    Q fever is a worldwide zoonosis caused by an intracellular bacillus named Coxiella burnetii (CB) and is a rare cause of vascular infections. We report a case of abdominal aortic aneurysm infected by CB with bilateral paravertebral abscesses and contiguous spondylodiscitis treated by open repair using a cryopreserved allograft and long-term antibiotic therapy by oral doxycycline and oral hydroxychloroquine for a duration of 18 months. Twenty months after the operation, the patient had no infections signs and vascular complication. PMID:26968369

  11. A serologic survey for Coxiella burnetii in semi-wild ungulates in the Emirate of Dubai, United Arab Emirates.

    PubMed

    Chaber, Anne-Lise; Lloyd, Christopher; O'Donovan, Declan; McKeown, Sean; Wernery, Ulrich; Bailey, Tom

    2012-01-01

    Q fever, a highly infectious zoonotic disease caused by Coxiella burnetii, has not been officially reported in the United Arab Emirates (UAE). This first serosurvey of a large group of semi-free-ranging animals in the UAE indicates that a wide range of ungulates have been exposed C. burnettii in the region.

  12. Complementation of Arginine Auxotrophy for Genetic Transformation of Coxiella burnetii by Use of a Defined Axenic Medium

    PubMed Central

    Sandoz, Kelsi M.; Beare, Paul A.; Cockrell, Diane C.

    2016-01-01

    ABSTRACT Host cell-free (axenic) culture of Coxiella burnetii in acidified citrate cysteine medium-2 (ACCM-2) has provided important opportunities for investigating the biology of this naturally obligate intracellular pathogen and enabled the development of tools for genetic manipulation. However, ACCM-2 has complex nutrient sources that preclude a detailed study of nutritional factors required for C. burnetii growth. Metabolic reconstruction of C. burnetii predicts that the bacterium cannot synthesize all amino acids and therefore must sequester some from the host. To examine C. burnetii amino acid auxotrophies, we developed a nutritionally defined medium with known amino acid concentrations, termed ACCM-D. Compared to ACCM-2, ACCM-D supported longer logarithmic growth, a more gradual transition to stationary phase, and approximately 5- to 10-fold greater overall replication. Small-cell-variant morphological forms generated in ACCM-D also showed increased viability relative to that generated in ACCM-2. Lack of growth in amino acid-deficient formulations of ACCM-D revealed C. burnetii auxotrophy for 11 amino acids, including arginine. Heterologous expression of Legionella pneumophila argGH in C. burnetii permitted growth in ACCM-D missing arginine and supplemented with citrulline, thereby providing a nonantibiotic means of selection of C. burnetii genetic transformants. Consistent with bioinformatic predictions, the elimination of glucose did not impair C. burnetii replication. Together, these results highlight the advantages of a nutritionally defined medium in investigations of C. burnetii metabolism and the development of genetic tools. IMPORTANCE Host cell-free growth and genetic manipulation of Coxiella burnetii have revolutionized research of this intracellular bacterial pathogen. Nonetheless, undefined components of growth medium have made studies of C. burnetii physiology difficult and have precluded the development of selectable markers for genetic

  13. Early cytokine and antibody responses against Coxiella burnetii in aerosol infection of BALB/c mice

    PubMed Central

    Schoffelen, Teske; Self, Joshua S.; Fitzpatrick, Kelly A.; Netea, Mihai G.; van Deuren, Marcel; Joosten, Leo A. B.; Kersh, Gilbert J.

    2016-01-01

    Coxiella burnetii, a Gram-negative intracellular bacterium, can give rise to Q fever in humans and is transmitted mainly by inhalation of infected aerosols from animal reservoirs. Serology is commonly used to diagnose Q fever, but the early cellular immune response –i.e. C. burnetii-specific interferon(IFN)-γ production in response to antigen challenge– might be an additional diagnostic. Detection of IFN-γ responses has been used to identify past and chronic Q fever infections, but the IFN-γ response in acute Q fever has not been described. By challenging immunocompetent BALB/c mice with aerosols containing phase I C. burnetii, the timing and extent of IFN-γ recall responses was evaluated in an acute C. burnetii infection. Other cytokines were also measured in an effort to identify other potential diagnostic markers. The data show that after initial expansion of bacteria first in lungs and then in other tissues, the infection was cleared from day 10 onwards as reflected by the decreasing number of bacteria. The antigen-induced IFN-γ production by splenocytes coincided with emergence of IgM phase II-antibodies at day 10 post-infection, and preceded appearance of IgG-antibodies. This was accompanied by the production of pro-inflammatory cytokines including IL-6, KC and IP-10, followed by MCP-1, but not by IL-1β and TNF-α, and only very low production of the anti-inflammatory cytokine IL-10. These data suggest that analysis of antigen-specific IFN-γ responses could be a useful tool for diagnosis of acute Q-fever. Moreover, the current model of C.burnetii infection could be used to give new insights into immunological factors that predispose to development of persistent infection. PMID:25618420

  14. Identification of Novel Small RNAs and Characterization of the 6S RNA of Coxiella burnetii

    PubMed Central

    Warrier, Indu; Hicks, Linda D.; Battisti, James M.; Raghavan, Rahul; Minnick, Michael F.

    2014-01-01

    Coxiella burnetii, an obligate intracellular bacterial pathogen that causes Q fever, undergoes a biphasic developmental cycle that alternates between a metabolically-active large cell variant (LCV) and a dormant small cell variant (SCV). As such, the bacterium undoubtedly employs complex modes of regulating its lifecycle, metabolism and pathogenesis. Small RNAs (sRNAs) have been shown to play important regulatory roles in controlling metabolism and virulence in several pathogenic bacteria. We hypothesize that sRNAs are involved in regulating growth and development of C. burnetii and its infection of host cells. To address the hypothesis and identify potential sRNAs, we subjected total RNA isolated from Coxiella cultured axenically and in Vero host cells to deep-sequencing. Using this approach, we identified fifteen novel C. burnetii sRNAs (CbSRs). Fourteen CbSRs were validated by Northern blotting. Most CbSRs showed differential expression, with increased levels in LCVs. Eight CbSRs were upregulated (≥2-fold) during intracellular growth as compared to growth in axenic medium. Along with the fifteen sRNAs, we also identified three sRNAs that have been previously described from other bacteria, including RNase P RNA, tmRNA and 6S RNA. The 6S regulatory sRNA of C. burnetii was found to accumulate over log phase-growth with a maximum level attained in the SCV stage. The 6S RNA-encoding gene (ssrS) was mapped to the 5′ UTR of ygfA; a highly conserved linkage in eubacteria. The predicted secondary structure of the 6S RNA possesses three highly conserved domains found in 6S RNAs of other eubacteria. We also demonstrate that Coxiella’s 6S RNA interacts with RNA polymerase (RNAP) in a specific manner. Finally, transcript levels of 6S RNA were found to be at much higher levels when Coxiella was grown in host cells relative to axenic culture, indicating a potential role in regulating the bacterium’s intracellular stress response by interacting with RNAP during

  15. Host and Environmental Factors Modulate the Exposure of Free-Ranging and Farmed Red Deer (Cervus elaphus) to Coxiella burnetii

    PubMed Central

    Velasco Ávila, Ana Luisa; Boadella, Mariana; Beltrán-Beck, Beatriz; Barasona, José Ángel; Santos, João P. V.; Queirós, João; García-Pérez, Ana L.; Barral, Marta; Ruiz-Fons, Francisco

    2015-01-01

    The control of multihost pathogens, such as Coxiella burnetii, should rely on accurate information about the roles played by the main hosts. We aimed to determine the involvement of the red deer (Cervus elaphus) in the ecology of C. burnetii. We predicted that red deer populations from broad geographic areas within a European context would be exposed to C. burnetii, and therefore, we hypothesized that a series of factors would modulate the exposure of red deer to C. burnetii. To test this hypothesis, we designed a retrospective survey of 47 Iberian red deer populations from which 1,751 serum samples and 489 spleen samples were collected. Sera were analyzed by enzyme-linked immunosorbent assays (ELISA) in order to estimate exposure to C. burnetii, and spleen samples were analyzed by PCR in order to estimate the prevalence of systemic infections. Thereafter, we gathered 23 variables—within environmental, host, and management factors—potentially modulating the risk of exposure of deer to C. burnetii, and we performed multivariate statistical analyses to identify the main risk factors. Twenty-three populations were seropositive (48.9%), and C. burnetii DNA in the spleen was detected in 50% of the populations analyzed. The statistical analyses reflect the complexity of C. burnetii ecology and suggest that although red deer may maintain the circulation of C. burnetii without third species, the most frequent scenario probably includes other wild and domestic host species. These findings, taken together with previous evidence of C. burnetii shedding by naturally infected red deer, point at this wild ungulate as a true reservoir for C. burnetii and an important node in the life cycle of C. burnetii, at least in the Iberian Peninsula. PMID:26150466

  16. Host and Environmental Factors Modulate the Exposure of Free-Ranging and Farmed Red Deer (Cervus elaphus) to Coxiella burnetii.

    PubMed

    González-Barrio, David; Velasco Ávila, Ana Luisa; Boadella, Mariana; Beltrán-Beck, Beatriz; Barasona, José Ángel; Santos, João P V; Queirós, João; García-Pérez, Ana L; Barral, Marta; Ruiz-Fons, Francisco

    2015-09-01

    The control of multihost pathogens, such as Coxiella burnetii, should rely on accurate information about the roles played by the main hosts. We aimed to determine the involvement of the red deer (Cervus elaphus) in the ecology of C. burnetii. We predicted that red deer populations from broad geographic areas within a European context would be exposed to C. burnetii, and therefore, we hypothesized that a series of factors would modulate the exposure of red deer to C. burnetii. To test this hypothesis, we designed a retrospective survey of 47 Iberian red deer populations from which 1,751 serum samples and 489 spleen samples were collected. Sera were analyzed by enzyme-linked immunosorbent assays (ELISA) in order to estimate exposure to C. burnetii, and spleen samples were analyzed by PCR in order to estimate the prevalence of systemic infections. Thereafter, we gathered 23 variables-within environmental, host, and management factors-potentially modulating the risk of exposure of deer to C. burnetii, and we performed multivariate statistical analyses to identify the main risk factors. Twenty-three populations were seropositive (48.9%), and C. burnetii DNA in the spleen was detected in 50% of the populations analyzed. The statistical analyses reflect the complexity of C. burnetii ecology and suggest that although red deer may maintain the circulation of C. burnetii without third species, the most frequent scenario probably includes other wild and domestic host species. These findings, taken together with previous evidence of C. burnetii shedding by naturally infected red deer, point at this wild ungulate as a true reservoir for C. burnetii and an important node in the life cycle of C. burnetii, at least in the Iberian Peninsula.

  17. Coxiella burnetii DNA, but not viable bacteria, in dairy products in France.

    PubMed

    Eldin, Carole; Angelakis, Emmanouil; Renvoisé, Aurélie; Raoult, Didier

    2013-04-01

    Transmission by the oral route of Coxiella burnetii is controversial. Our objective was to evaluate dairy products in the transmission of Q fever. Pasteurized, unpasteurized, and thermized dairy products were tested for C. burnetii by using a quantitative polymerase chain reaction specific for IS1111 and IS30A spacers, culturing in human embryonic lung fibroblasts cells, and inoculation into BALB/c mice. We tested 201 products and C. burnetii was identified in 64%. Cow milk origin products were more frequently positive than goat or ewe products (P = 0.006 and P = 0.0001, respectively), and industrial food was more frequently positive than artisanal food (P < 0.0001). Food made from unpasteurized milk contained higher bacteria concentrations than food made from pasteurized milk (P = 0.02). All cultures were negative and mice did not show signs of illness. Farm animals are highly infected in France but consumption of cheese and yogurt does not seem to pose a public health risk for transmission of Q fever.

  18. Apoptosis in normal and Coxiella burnetii-infected placentas from Alaskan northern fur seals (Callorhinus ursinus).

    PubMed

    Myers, E; Ehrhart, E J; Charles, B; Spraker, T; Gelatt, T; Duncan, C

    2013-07-01

    In 2010, Coxiella burnetii was identified in 75% of northern fur seal placentas from a single rookery in Alaska, but nothing was known about the significance of this organism in the population. Although many infectious organisms cause increased cell death, C. burnetii has been shown to suppress apoptosis of the host macrophages as an intracellular survival mechanism. To determine if infection induces a similar functional change in the placenta, immunohistochemistry for antibodies to cleaved caspase-3 (activated caspase-3) and the (TDT)-mediated dUTP-digoxigenin nick end labeling (TUNEL) technique were used to compare the amount of placental apoptosis in infected and noninfected placentas. There was a statistically significant difference in the frequency of apoptotic cells between infected and uninfected placentas, with more apoptosis identified in the uninfected placentas. This finding suggests that the survival mechanism of C. burnetii in host macrophages to reduce apoptosis may also be utilized in trophoblasts. The significance of decreased trophoblastic apoptosis for the northern fur seal fetus requires further investigation.

  19. Prevalence and risk factors for Coxiella burnetii (Q fever) in Dutch dairy cattle herds based on bulk tank milk testing.

    PubMed

    van Engelen, E; Schotten, N; Schimmer, B; Hautvast, J L A; van Schaik, G; van Duijnhoven, Y T H P

    2014-11-01

    Despite cattle herds can harbor Coxiella burnetii, risk factors for C. burnetii presence in dairy cattle herds are largely unknown. Therefore, C. burnetii herd prevalence and risk factors for bulk tank milk (BTM) positivity were investigated. In this cross-sectional study, a questionnaire was filled out by the farmer and BTM from 301 farms was tested by ELISA for presence of C. burnetii antibodies and PCR for presence of C. burnetii DNA. Risk factors were identified by univariable and multivariable logistic regression analyses. Antibodies to C. burnetii were detected in 81.6% (CI: 77.2-85.9) and C. burnetii DNA in 18.8% (CI: 14.4-23.1) of the BTM samples. Herd size (OR=1.1 per 10 cows), cleaning the bedding of the cubicles at most every other day (OR=2.8) and purchase of cattle from at least two addresses (OR=3.1) showed a significant and positive association with ELISA positivity and use of an automatic milking system a negative association (OR=0.3). Risk factors for PCR positivity were purchase of cattle from at least two delivery addresses (OR=3.2), presence of cows with ticks (OR=2.0), use of an automatic milking system (OR=0.2) and presence of goats or sheep on the farm (OR=0.4). Biosecurity and general hygiene seem associated with introduction and spread of C. burnetii in dairy herds. PMID:25239684

  20. Quantitation of viable Coxiella burnetii in milk using an integrated cell culture-polymerase chain reaction (ICC-PCR) assay.

    PubMed

    Stewart, Diana; Shieh, Y-Carol; Tortorello, Mary; Kukreja, Ankush; Shazer, Arlette; Schlesser, Joseph

    2015-11-01

    The obligate intracellular pathogen Coxiella burnetii has long been considered the most heat resistant pathogen in raw milk, making it the reference pathogen for determining pasteurisation conditions for milk products. New milk formulations and novel non-thermal processes require validation of effectiveness which requires a more practical method for analysis than using the currently used animal model for assessing Coxiella survival. Also, there is an interest in better characterising thermal inactivation of Coxiella in various milk formulations. To avoid the use of the guinea pig model for evaluating Coxiella survival, an Integrated Cell Culture-PCR (ICC-PCR) method was developed for determining Coxiella viability in milk. Vero cell cultures were directly infected from Coxiella-contaminated milk in duplicate 24-well plates. Viability of the Coxiella in milk was shown by a ≥ 0.5 log genome equivalent (ge)/ml increase in the quantity of IS111a gene from the baseline post-infection (day 0) level after 9-11 d propagation. Coxiella in skim, 2%, and whole milk, and half and half successfully infected Vero cells and increased in number by at least 2 logs using a 48-h infection period followed by 9-d propagation time. As few as 125 Coxiella ge/ml in whole milk was shown to infect and propagate at least 2 logs in the optimised ICC-PCR assay, though variable confirmation of propagation was shown for as low as 25 Coxiella ge/ml. Applicability of the ICC-PCR method was further proven in an MPN format to quantitate the number of viable Coxiella remaining in whole milk after 60 °C thermal treatment at 0, 20, 40, 60 and 90 min.

  1. Coxiella burnetii Induces Inflammatory Interferon-Like Signature in Plasmacytoid Dendritic Cells: A New Feature of Immune Response in Q Fever

    PubMed Central

    Ka, Mignane B.; Mezouar, Soraya; Ben Amara, Amira; Raoult, Didier; Ghigo, Eric; Olive, Daniel; Mege, Jean-Louis

    2016-01-01

    Plasmacytoid dendritic cells (pDCs) play a major role in antiviral immunity via the production of type I interferons (IFNs). There is some evidence that pDCs interact with bacteria but it is not yet clear whether they are protective or contribute to bacterial pathogenicity. We wished to investigate whether Coxiella burnetii, the agent of Q fever, interacts with pDCs. The stimulation of pDCs with C. burnetii increased the expression of activation and migratory markers (CD86 and CCR7) as determined by flow cytometry and modulated gene expression program as revealed by a microarray approach. Indeed, genes encoding for pro-inflammatory cytokines, chemokines, and type I INF were up-regulated. The up-regulation of type I IFN was correlated with an increase in IFN-α release by C. burnetii-stimulated pDCs. We also investigated pDCs in patients with Q fever endocarditis. Using flow cytometry and a specific gating strategy, we found that the number of circulating pDCs was significantly lower in patients with Q fever endocarditis as compared to healthy donors. In addition, the remaining circulating pDCs expressed activation and migratory markers. As a whole, our study identified non-previously reported activation of pDCs by C. burnetii and their modulation during Q fever. PMID:27446817

  2. Coxiella burnetii Induces Inflammatory Interferon-Like Signature in Plasmacytoid Dendritic Cells: A New Feature of Immune Response in Q Fever.

    PubMed

    Ka, Mignane B; Mezouar, Soraya; Ben Amara, Amira; Raoult, Didier; Ghigo, Eric; Olive, Daniel; Mege, Jean-Louis

    2016-01-01

    Plasmacytoid dendritic cells (pDCs) play a major role in antiviral immunity via the production of type I interferons (IFNs). There is some evidence that pDCs interact with bacteria but it is not yet clear whether they are protective or contribute to bacterial pathogenicity. We wished to investigate whether Coxiella burnetii, the agent of Q fever, interacts with pDCs. The stimulation of pDCs with C. burnetii increased the expression of activation and migratory markers (CD86 and CCR7) as determined by flow cytometry and modulated gene expression program as revealed by a microarray approach. Indeed, genes encoding for pro-inflammatory cytokines, chemokines, and type I INF were up-regulated. The up-regulation of type I IFN was correlated with an increase in IFN-α release by C. burnetii-stimulated pDCs. We also investigated pDCs in patients with Q fever endocarditis. Using flow cytometry and a specific gating strategy, we found that the number of circulating pDCs was significantly lower in patients with Q fever endocarditis as compared to healthy donors. In addition, the remaining circulating pDCs expressed activation and migratory markers. As a whole, our study identified non-previously reported activation of pDCs by C. burnetii and their modulation during Q fever. PMID:27446817

  3. Improved method for preparation of samples for the polymerase chain reaction for detection of Coxiella burnetii in milk using immunomagnetic separation.

    PubMed

    Muramatsu, Y; Maruyama, M; Yanase, T; Ueno, H; Morita, C

    1996-07-01

    Immunomagnetic separation (IMS) improved the detection of Coxiella burnetii in cow's milk by the polymerase chain reaction (PCR). IMS represents a novel approach to the isolation of microorganism from milk. The combination of IMS and PCR analysis has an adequate sensitivity for detection of C. burnetii.

  4. Rapid method for detection of Coxiella burnetii antibodies using high-density particle agglutination.

    PubMed Central

    Nguyen, S V; Otsuka, H; Zhang, G Q; To, H; Yamaguchi, T; Fukushi, H; Noma, A; Hirai, K

    1996-01-01

    A high-density particle agglutination test, using erythrocyte-sensitizing substance from phase II Coxiella burnetii adsorbed to high-density composite particles, was developed for rapid serodiagnosis of Q fever. The test was compared with the microimmunofluorescence test for sensitivity and specificity by using 3,036 human serum samples collected in Gifu Prefecture, Japan. An excellent agreement was found between the two tests for the acute-phase group and paired serum samples, but some discordant results were observed in the single-sample group. The sensitivity and specificity of the high-density particle agglutination test were both 100% in the former group and 81.6 and 99.9%, respectively, in the latter group. The test is a very promising tool for routine serodiagnosis of Q fever because of its simplicity, sensitivity, and specificity. PMID:8940428

  5. Occurrence of Coxiella burnetii and Chlamydiales species in abortions of domestic ruminants and in wild ruminants in Hungary, Central Europe.

    PubMed

    Kreizinger, Zsuzsa; Szeredi, Levente; Bacsadi, Árpád; Nemes, Csaba; Sugár, László; Varga, Tamás; Sulyok, Kinga M; Szigeti, Alexandra; Ács, Kornél; Tóbiás, Enikő; Borel, Nicole; Gyuranecz, Miklós

    2015-03-01

    Coxiella burnetii and certain members of the Chlamydiales order are zoonotic, intracellular, Gram-negative bacteria, with abortigenic potential in ruminants. These pathogens have a broad host range and worldwide geographical distribution. The current study aimed to reveal the importance of C. burnetii and Chlamydiales spp. in abortions in domestic ruminants and their occurrence in wild ruminants with real-time polymerase chain reaction (qPCR) assays, histology, and immunohistochemical staining (IHC). From the 111 abortion cases of domestic ruminants examined, C. burnetii was detected in 33 placenta samples (cattle, n = 22; sheep, n = 10; goat, n = 1), and members of the Chlamydiales order were detected in 32 placenta samples (cattle, n = 14; sheep, n = 16; goat, n = 2) using qPCR. Coinfection with both C. burnetii and Chlamydiales spp. were identified in 12 cases (cattle, n = 3; sheep, n = 8; goat, n = 1) out of the qPCR-positive samples. The presence of the relevant antigen was confirmed by IHC in 20 cases (C. burnetii, n = 2, in sheep; Chlamydiaceae, n = 17, in sheep [n = 15] and goat [n = 2]; and both pathogens in 1 sheep). Coxiella burnetii was identified in 2.2% (2/91) of the wild ruminants, but the samples were negative by IHC. Uncultured Chlamydiales spp. were detected in 4.4% (4/91) of the placenta samples by qPCR. In conclusion, Q fever is widespread among domestic ruminants in Hungary, and, in several cases, C. burnetii was implicated as the primary cause of abortions. Waddlia chondrophila, Parachlamydia spp., and uncultured Chlamydiales spp. were present only sporadically in samples from cattle and wild ruminants.

  6. Myeloid decidual dendritic cells and immunoregulation of pregnancy: defective responsiveness to Coxiella burnetii and Brucella abortus

    PubMed Central

    Gorvel, Laurent; Ben Amara, Amira; Ka, Mignane B.; Textoris, Julien; Gorvel, Jean-Pierre; Mege, Jean-Louis

    2014-01-01

    Dendritic cells (DCs) are a component of the placental immune system, but their role in pregnancy is still poorly understood. Decidual DCs (dDCs) were selected from at-term pregnancy on the basis of CD14 and CD11c expression. A phenotypic analysis revealed that dDCs are characterized by the expression of monocyte-derived DC (moDCs) markers and specific markers such as HLA-G and its ligand ILT4. As demonstrated by whole-genome microarray, dDCs expressed a specific gene program markedly distinct from that of moDCs; it included estrogen- and progesterone-regulated genes and genes encoding immunoregulatory cytokines, which is consistent with the context of foeto-maternal tolerance. A functional analysis of dDCs showed that they were unable to mature in response to bacterial ligands such as lipopolysaccharide or peptidoglycan, as assessed by the expression of HLA-DR, CD80, CD83, and CD86. When dDCs were incubated with bacteria known for their placenta tropism, Coxiella burnetii and Brucella abortus, they were also unable to mature and to produce inflammatory cytokines. It is likely that the defective maturation of dDCs and their inability to produce inflammatory cytokines is related to the spontaneous release of IL-10 by these cells. Taken together, these results suggest that dDCs exhibit an immunoregulatory program, which may favor the pathogenicity of C. burnetii or B. abortus. PMID:25566514

  7. Cloning and characterization of an autonomous replication sequence from Coxiella burnetii.

    PubMed Central

    Suhan, M; Chen, S Y; Thompson, H A; Hoover, T A; Hill, A; Williams, J C

    1994-01-01

    A Coxiella burnetii chromosomal fragment capable of functioning as an origin for the replication of a kanamycin resistance (Kanr) plasmid was isolated by use of origin search methods utilizing an Escherichia coli host. The 5.8-kb fragment was subcloned into phagemid vectors and was deleted progressively by an exonuclease III-S1 technique. Plasmids containing progressively shorter DNA fragments were then tested for their capability to support replication by transformation of an E. coli polA strain. A minimal autonomous replication sequence (ARS) was delimited to 403 bp. Sequencing of the entire 5.8-kb region revealed that the minimal ARS contained two consensus DnaA boxes, three A + T-rich 21-mers, a transcriptional promoter leading rightwards, and potential integration host factor and factor of inversion stimulation binding sites. Database comparisons of deduced amino acid sequences revealed that open reading frames located around the ARS were homologous to genes often, but not always, found near bacterial chromosomal origins; these included identities with rpmH and rnpA in E. coli and identities with the 9K protein and 60K membrane protein in E. coli and Pseudomonas species. These and direct hybridization data suggested that the ARS was chromosomal and not associated with the resident plasmid QpH1. Two-dimensional agarose gel electrophoresis did not reveal the presence of initiating intermediates, indicating that the ARS did not initiate chromosome replication during laboratory growth of C. burnetii. Images PMID:8071197

  8. Chloroform-Methanol Residue of Coxiella burnetii Markedly Potentiated the Specific Immunoprotection Elicited by a Recombinant Protein Fragment rOmpB-4 Derived from Outer Membrane Protein B of Rickettsia rickettsii in C3H/HeN Mice

    PubMed Central

    Gong, Wenping; Wang, Pengcheng; Xiong, Xiaolu; Jiao, Jun; Yang, Xiaomei; Wen, Bohai

    2015-01-01

    The obligate intracellular bacteria, Rickettsia rickettsii and Coxiella burnetii, are the potential agents of bio-warfare/bio-terrorism. Here C3H/HeN mice were immunized with a recombinant protein fragment rOmp-4 derived from outer membrane protein B, a major protective antigen of R. rickettsii, combined with chloroform-methanol residue (CMR) extracted from phase I C. burnetii organisms, a safer Q fever vaccine. These immunized mice had significantly higher levels of IgG1 and IgG2a to rOmpB-4 and interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α), two crucial cytokines in resisting intracellular bacterial infection, as well as significantly lower rickettsial loads and slighter pathological lesions in organs after challenge with R. rickettsii, compared with mice immunized with rOmpB-4 or CMR alone. Additionally, after challenge with C. burnetii, the coxiella loads in the organs of these mice were significantly lower than those of mice immunized with rOmpB-4 alone. Our results prove that CMR could markedly potentiate enhance the rOmpB-4-specific immunoprotection by promoting specific and non-specific immunoresponses and the immunization with the protective antigen of R. rickettsii combined with CMR of C. burnetii could confer effective protection against infection of R. rickettsii or C. burnetii. PMID:25909586

  9. Genotyping of Coxiella burnetii from domestic ruminants and human in Hungary: indication of various genotypes

    PubMed Central

    2014-01-01

    Background Information about the genotypic characteristic of Coxiella burnetii from Hungary is lacking. The aim of this study is to describe the genetic diversity of C. burnetii in Hungary and compare genotypes with those found elsewhere. A total of 12 samples: (cattle, n = 6, sheep, n = 5 and human, n = 1) collected from across Hungary were studied by a 10-loci multispacer sequence typing (MST) and 6-loci multiple-locus variable-number of tandem repeat analysis (MLVA). Phylogenetic relationships among MST genotypes show how these Hungarian samples are related to others collected around the world. Results Three MST genotypes were identified: sequence type (ST) 20 has also been identified in ruminants from other European countries and the USA, ST28 was previously identified in Kazakhstan, and the proposed ST37 is novel. All MST genotypes yielded different MLVA genotypes and three different MLVA genotypes were identified within ST20 samples alone. Two novel MLVA types 0-9-5-5-6-2 (AG) and 0-8-4-5-6-2 (AF) (Ms23-Ms24-Ms27-Ms28-Ms33-Ms34) were defined in the ovine materials correlated with ST28 and ST37. Samples from different parts of the phylogenetic tree were associated with different hosts, suggesting host-specific adaptations. Conclusions Even with the limited number of samples analysed, this study revealed high genetic diversity among C. burnetii in Hungary. Understanding the background genetic diversity will be essential in identifying and controlling outbreaks. PMID:24885415

  10. Molecular and serologic detection of Coxiella burnetii in native Korean goats (Capra hircus coreanae).

    PubMed

    Jung, Byeong Yeal; Seo, Min-Goo; Lee, Seung-Hun; Byun, Jae-Won; Oem, Jae-Ku; Kwak, Dongmi

    2014-09-17

    The occurrence of Q fever in native Korean goats (Capra hircus coreanae) was investigated for the first time in the country using ELISA and PCR. A total of 597 blood samples were collected from goats belonging to five different provinces of Korea. To detect Coxiella burnetii, sera were separated from the whole blood and analysed by ELISA; DNA was extracted directly from the whole blood and analysed by PCR. Overall, 114 (19.1%, 95% C.I.=16.1-22.4) and 57 goats (9.5%, 95% C.I.=7.5-12.2) tested positive for C. burnetii in the ELISA- and PCR-based screening, respectively, while 18 goats (3.0%, 95% C.I.=1.9-4.7) tested positive in both the assays. There was a significant difference between the number of ELISA- and PCR-positive goats (P<0.05). The seroprevalence of Q fever was significantly higher among the adult goats (≥1y, 22.0%) than among the young goats (<1y, 13.8%) (P<0.05). While the results of the serologic analysis showed no seasonal variation, data from the PCR-based assay indicated that there were a higher number of positive cases during the cold seasons. Because Q fever infection has high rates of prevalence in native Korean goats, further studies on humans at a high risk of contracting this disease should be conducted. The PCR-based assay used in this study is a useful method for the direct detection of C. burnetii in blood samples from small ruminants. PMID:25061007

  11. B-cell non-Hodgkin lymphoma linked to Coxiella burnetii.

    PubMed

    Melenotte, Cléa; Million, Matthieu; Audoly, Gilles; Gorse, Audrey; Dutronc, Hervé; Roland, Gauthier; Dekel, Michal; Moreno, Asuncion; Cammilleri, Serge; Carrieri, Maria Patrizia; Protopopescu, Camelia; Ruminy, Philippe; Lepidi, Hubert; Nadel, Bertrand; Mege, Jean-Louis; Xerri, Luc; Raoult, Didier

    2016-01-01

    Bacteria can induce human lymphomas, whereas lymphoproliferative disorders have been described in patients with Q fever. We observed a lymphoma in a patient with Q fever that prompted us to investigate the association between the 2 diseases. We screened 1468 consecutive patients of the 2004 to 2014 French National Referral Center for Q fever database. The standardized incidence ratios (SIRs) of diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL) were calculated comparatively to the 2012 Francim Registry. The presence of Coxiella burnetii was tested using immunofluorescence and fluorescence in situ hybridization using a specific 16S ribosomal RNA probe and genomic DNA probe. Seven patients (0.48%) presented mature B-cell lymphoma consisting of 6 DLBCL and 1 FL. An excess risk of DLBCL and FL was found in Q fever patients compared with the general population (SIR [95% confidence interval], 25.4 [11.4-56.4] and 6.7 [0.9-47.9], respectively). C burnetii was detected in CD68(+) macrophages within both lymphoma and lymphadenitis tissues but localization in CD123(+) plasmacytoid dendritic cells (pDCs) was found only in lymphoma tissues. Q fever patients with persistent focalized infection were found more at risk of lymphoma (hazard ratio, 9.35 [1.10-79.4]). Interleukin-10 (IL10) overproduction (P = .0003) was found in patients developing lymphoma. These results suggest that C burnetii should be added to the list of bacteria that promote human B-cell non-Hodgkin lymphoma, possibly by the infection of pDCs and IL10 overproduction. Screening for early lymphoma diagnosis should be considered in the management of patients with Q fever, especially those with persistent focalized infections. PMID:26463422

  12. Reproductive performance of high producing lactating cows in Coxiella-infected herds following vaccination with phase-I Coxiella burnetii vaccine during advanced pregnancy.

    PubMed

    López-Helguera, I; López-Gatius, F; Tutusaus, J; Garcia-Ispierto, I

    2013-06-26

    This study was designed to assess the safety of phase I vaccination against Coxiella burnetii in advanced pregnancy and the effect of vaccination on subsequent reproductive performance of high producing dairy cows. C. burnetii serostatus was determined in 719 dairy cows by individual serological testing. According to their serostatus, cows were randomly assigned to a control (n=359) or vaccine (n=360) group (inactivated phase I on Days 171-177 and 192-198 of gestation, Coxevac-Ceva Sante Animale). Using a χ(2)-test, vaccination had no effect on abortion before parturition, retention of placenta and stillbirth, either in seropositive as in seronegative cows. Cox's proportional hazards model revealed that cows in the vaccine group were 1.22 times more likely to conceive during the first 150 days in milk than cows in the control group. Moreover, the likelihood of pregnancy was lower in multiparous cows, cows with a retained placenta and cows undergoing first AI during the warm season compared to the remaining animals (by factors of 0.75, 0.69 and 0.69, respectively). In animals testing seronegative for C. burnetii, the likelihood of pregnancy was 1.25 times higher in vaccinated cows compared to non-vaccinated seronegative animals. No effect of vaccination on subsequent fertility was detected in seropositive animals. In conclusion, the results of this study indicate that phase I vaccination against C. burnetii during advanced pregnancy in dairy cows is safe and improves subsequent fertility of C. burnetii seronegative animals.

  13. LAMP proteins account for the maturation delay during the establishment of the Coxiella burnetii-containing vacuole.

    PubMed

    Schulze-Luehrmann, Jan; Eckart, Rita A; Ölke, Martha; Saftig, Paul; Liebler-Tenorio, Elisabeth; Lührmann, Anja

    2016-02-01

    The obligate intracellular pathogen Coxiella burnetii replicates in a large phagolysosomal-like vacuole. Currently, both host and bacterial factors required for creating this replicative parasitophorous C. burnetii-containing vacuole (PV) are poorly defined. Here, we assessed the contributions of the most abundant proteins of the lysosomal membrane, LAMP-1 and LAMP-2, to the establishment and maintenance of the PV. Whereas these proteins were not critical for uptake of C. burnetii, they influenced the intracellular replication of C. burnetii. In LAMP-1/2 double-deficient fibroblasts as well as in LAMP-1/2 knock-down cells, C. burnetii establishes a significantly smaller, yet faster maturing vacuole, which harboured more bacteria. The accelerated maturation of PVs in LAMP double-deficient fibroblasts, which was partially or fully reversed by ectopic expression of LAMP-1 or LAMP-2, respectively, was characterized by an increased fusion rate with endosomes, lysosomes and bead-containing phagosomes, but not by different fusion kinetics with autophagy vesicles. These findings establish that LAMP proteins are critical for the maturation delay of PVs. Unexpectedly, neither the creation of the spacious vacuole nor the delay in maturation was found to be prerequisites for the intracellular replication of C. burnetii.

  14. Coxiella burnetii Phagocytosis Is Regulated by GTPases of the Rho Family and the RhoA Effectors mDia1 and ROCK

    PubMed Central

    Distel, Jesús S.; Aguilera, Milton O.; Colombo, María I.; Berón, Walter

    2015-01-01

    The GTPases belonging to the Rho family control the actin cytoskeleton rearrangements needed for particle internalization during phagocytosis. ROCK and mDia1 are downstream effectors of RhoA, a GTPase involved in that process. Coxiella burnetii, the etiologic agent of Q fever, is internalized by the host´s cells in an actin-dependent manner. Nevertheless, the molecular mechanism involved in this process has been poorly characterized. This work analyzes the role of different GTPases of the Rho family and some downstream effectors in the internalization of C. burnetii by phagocytic and non-phagocytic cells. The internalization of C. burnetii into HeLa and RAW cells was significantly inhibited when the cells were treated with Clostridium difficile Toxin B which irreversibly inactivates members of the Rho family. In addition, the internalization was reduced in HeLa cells that overexpressed the dominant negative mutants of RhoA, Rac1 or Cdc42 or that were knocked down for the Rho GTPases. The pharmacological inhibition or the knocking down of ROCK diminished bacterium internalization. Moreover, C. burnetii was less efficiently internalized in HeLa cells overexpressing mDia1-N1, a dominant negative mutant of mDia1, while the overexpression of the constitutively active mutant mDia1-ΔN3 increased bacteria uptake. Interestingly, when HeLa and RAW cells were infected, RhoA, Rac1 and mDia1 were recruited to membrane cell fractions. Our results suggest that the GTPases of the Rho family play an important role in C. burnetii phagocytosis in both HeLa and RAW cells. Additionally, we present evidence that ROCK and mDia1, which are downstream effectors of RhoA, are involved in that process. PMID:26674774

  15. Coxiella burnetii Phagocytosis Is Regulated by GTPases of the Rho Family and the RhoA Effectors mDia1 and ROCK.

    PubMed

    Salinas, Romina P; Ortiz Flores, Rodolfo M; Distel, Jesús S; Aguilera, Milton O; Colombo, María I; Berón, Walter

    2015-01-01

    The GTPases belonging to the Rho family control the actin cytoskeleton rearrangements needed for particle internalization during phagocytosis. ROCK and mDia1 are downstream effectors of RhoA, a GTPase involved in that process. Coxiella burnetii, the etiologic agent of Q fever, is internalized by the host´s cells in an actin-dependent manner. Nevertheless, the molecular mechanism involved in this process has been poorly characterized. This work analyzes the role of different GTPases of the Rho family and some downstream effectors in the internalization of C. burnetii by phagocytic and non-phagocytic cells. The internalization of C. burnetii into HeLa and RAW cells was significantly inhibited when the cells were treated with Clostridium difficile Toxin B which irreversibly inactivates members of the Rho family. In addition, the internalization was reduced in HeLa cells that overexpressed the dominant negative mutants of RhoA, Rac1 or Cdc42 or that were knocked down for the Rho GTPases. The pharmacological inhibition or the knocking down of ROCK diminished bacterium internalization. Moreover, C. burnetii was less efficiently internalized in HeLa cells overexpressing mDia1-N1, a dominant negative mutant of mDia1, while the overexpression of the constitutively active mutant mDia1-ΔN3 increased bacteria uptake. Interestingly, when HeLa and RAW cells were infected, RhoA, Rac1 and mDia1 were recruited to membrane cell fractions. Our results suggest that the GTPases of the Rho family play an important role in C. burnetii phagocytosis in both HeLa and RAW cells. Additionally, we present evidence that ROCK and mDia1, which are downstream effectors of RhoA, are involved in that process.

  16. Coxiella burnetii (Q-Fever) Seroprevalence in Prey and Predators in the United Kingdom: Evaluation of Infection in Wild Rodents, Foxes and Domestic Cats Using a Modified ELISA.

    PubMed

    Meredith, A L; Cleaveland, S C; Denwood, M J; Brown, J K; Shaw, D J

    2015-12-01

    Coxiella burnetii, the agent of Q-fever, is recognized as a worldwide zoonosis with a wide host range and potentially complex reservoir systems. Infected ruminants are the main source of infection for humans, but cats and other mammals, including wild rodents, also represent potential sources of infection. There has been a recent upsurge of reported cases in humans, domestic ruminants and wildlife in many parts of the world, and studies have indicated that wild brown rats may act as true reservoirs for C. burnetii and be implicated in outbreaks in livestock and humans. However, investigation of reservoir systems is limited by lack of validated serological tests for wildlife or other non-target species. In this study, serum samples from 796 wild rodents (180 bank voles, 309 field voles, 307 wood mice) 102 wild foxes and 26 domestic cats from three study areas in the UK were tested for the presence of antibodies to C. burnetii using a commercial indirect ELISA kit modified for use in multiple wildlife species. Test thresholds were determined for each species in the absence of species-specific reference sera using a bi-modal latent class mixture model to discriminate between positive from negative results. Based on the thresholds determined, seroprevalence in the wild rodents ranged from 15.6% to 19.1% depending on species (overall 17.3%) and was significantly higher in both foxes (41.2%) and cats (61.5%) than in rodents. This is the first report to quantify seroprevalence to C. burnetii in bank voles, field voles, wood mice, foxes and cats in the UK and provides evidence that predator species could act as indicators for the presence of C. burnetii in rodents. The study demonstrates that wildlife species could be significant reservoirs of infection for both livestock and humans, and the high seroprevalence in domestic cats highlights the potential zoonotic risk from this species.

  17. Coxiella burnetii seropositivity and associated risk factors in goats in Ontario, Canada.

    PubMed

    Meadows, S; Jones-Bitton, A; McEwen, S; Jansen, J; Menzies, P

    2015-10-01

    Coxiella burnetii is a zoonotic bacterium, and infection in goats with this bacterium can result in abortion, stillbirth or birth of non-viable kids. A cross-sectional study was conducted to identify the seroprevalence and risk factors for C. burnetii exposure in Ontario goats. Sera were collected between August 2010 and February 2012, and tested for C. burnetii specific antibodies using an enzyme-linked immunosorbent assay (IDEXX). Overall, 63.2% (48/76, 95% CI=51.9-73.4) of farms had one or more seropositive goats. A higher farm-level seroprevalence of 78.6% (33/42) was found on dairy goat farms, compared to 44.1% (15/34) on meat goat farms (p<0.01). At the overall individual-animal level, 32.5% (714/2195, 95% CI=30.6-34.5) of goats were seropositive. Similarly, a higher individual-level seroprevalence was identified for dairy goats (43.7%, 633/1447) compared to meat goats (10.8%, 81/748) (p<0.001). A mixed multivariable logistic model that controlled for farm-level clustering identified risk factors associated with seropositivity (p<0.05). Increases in the female herd size (logarithmic scale) were associated with increased odds of seropositivity, while increases in male herd size had a negative association with seropositivity. If other sheep or goat farms were located in a 5-km radius, goats had 5.6 times (95% CI=1.01-30.8) times the odds of seropositivity compared to those that were not. Relative to goats from farms where all kidding pen hygiene was practiced (adding bedding, removing birth materials and disinfection after kidding), goats from farms which only added bedding and removed birth materials had a higher odds of seropositivity (OR=19.3, 95% CI=1.1-330.4), as did goats from farms which practiced none of these measures (OR=161.0, 95% CI=2.4-10822.2). An interaction term revealed kidding outdoors when there were no swine on farm had a protective effect on seropositivity compared to kidding indoors, or kidding outdoors with swine on the farm. These

  18. Applying Fluorescence Resonance Energy Transfer (FRET) to Examine Effector Translocation Efficiency by Coxiella burnetii during siRNA Silencing.

    PubMed

    Newton, Patrice; Latomanski, Eleanor A; Newton, Hayley J

    2016-07-06

    Coxiella burnetii, the causative agent of Q fever, is an intracellular pathogen that relies on a Type IV Dot/Icm Secretion System to establish a replicative niche. A cohort of effectors are translocated through this system into the host cell to manipulate host processes and allow the establishment of a unique lysosome-derived vacuole for replication. The method presented here involves the combination of two well-established techniques: specific gene silencing using siRNA and measurement of effector translocation using a FRET-based substrate that relies on β-lactamase activity. Applying these two approaches, we can begin to understand the role of host factors in bacterial secretion system function and effector translocation. In this study we examined the role of Rab5A and Rab7A, both important regulators of the endocytic trafficking pathway. We demonstrate that silencing the expression of either protein results in a decrease in effector translocation efficiency. These methods can be easily modified to examine other intracellular and extracellular pathogens that also utilize secretion systems. In this way, a global picture of host factors involved in bacterial effector translocation may be revealed.

  19. Applying Fluorescence Resonance Energy Transfer (FRET) to Examine Effector Translocation Efficiency by Coxiella burnetii during siRNA Silencing.

    PubMed

    Newton, Patrice; Latomanski, Eleanor A; Newton, Hayley J

    2016-01-01

    Coxiella burnetii, the causative agent of Q fever, is an intracellular pathogen that relies on a Type IV Dot/Icm Secretion System to establish a replicative niche. A cohort of effectors are translocated through this system into the host cell to manipulate host processes and allow the establishment of a unique lysosome-derived vacuole for replication. The method presented here involves the combination of two well-established techniques: specific gene silencing using siRNA and measurement of effector translocation using a FRET-based substrate that relies on β-lactamase activity. Applying these two approaches, we can begin to understand the role of host factors in bacterial secretion system function and effector translocation. In this study we examined the role of Rab5A and Rab7A, both important regulators of the endocytic trafficking pathway. We demonstrate that silencing the expression of either protein results in a decrease in effector translocation efficiency. These methods can be easily modified to examine other intracellular and extracellular pathogens that also utilize secretion systems. In this way, a global picture of host factors involved in bacterial effector translocation may be revealed. PMID:27501079

  20. Antigenic differences between Coxiella burnetii cells revealed by postembedding immunoelectron microscopy and immunoblotting.

    PubMed Central

    McCaul, T F; Banerjee-Bhatnagar, N; Williams, J C

    1991-01-01

    The aim of this study was to investigate the antigenic structures of the morphologically distinct cells of the Coxiella burnetii developmental cycle. Postembedding immunoelectron microscopy with polyclonal antibodies produced in rabbits to (i) phase I cells, (ii) a chloroform-methanol residue fraction of cells, (iii) the cell walls (CW) of large and small cells and small dense cells (SDC), and (iv) the peptidoglycan-protein complexes of small cells and SDC labelled the continuum of morphologically distinct cells. But these antibodies did not distinguish between the antigenic structures of the various cells. Monoclonal antibodies to the phase I lipopolysaccharide labelled the CW of a majority of the smaller cells, but there was diminished reactivity to the larger cells. Although monoclonal antibodies to a 29.5-kDa outer membrane protein labelled the CW of the large mother cells, the large cells, and the small cells, a minority of the SDC with compact CW were not labelled. The endogenous spore within the mother cell was not labelled by the polyclonal or monoclonal antibodies to cellular components. A selected population of SDC was prepared by osmotic lysis of large cells, differential centrifugation, Renografin step-gradient fractionation, and breakage of the small cells in a French press at 20,000 lb/in2. The pressure-resistant SDC collected as fraction CL did not contain the 29.5-kDa protein, as evidenced by the lack of (i) Coomassie brilliant blue staining of protein in the 29.5-kDa region of sodium dodecyl sulfate-polyacrylamide gels and (ii) reactivity of the 29.5-kDa protein antigenic epitopes in immunoblotting with monoclonal antibodies to the protein. In contrast, CW of the pressure-sensitive small cells contained the 29.5-kDa protein. Therefore, the observed ultrastructural differences between large and small cells and SDC reflect differences in sensitivity to breakage by pressure treatment and in cell-associated antigens. Although the process of

  1. Effects of long-term vaccination against Coxiella burnetii on the fertility of high-producing dairy cows.

    PubMed

    Garcia-Ispierto, Irina; López-Helguera, Irene; Tutusaus, Joan; Mur-Novales, Ramón; López-Gatius, Fernando

    2015-06-01

    The impact of long-term vaccination against Coxiella burnetii on the fertility of cows was studied. Double vaccinations three weeks apart at the start of the third trimester of gestation in each of two consecutive pregnancies were applied. The final study population consisted of 410 cows after the first vaccination round. Based on the odds ratios, the likelihood of early fetal loss (pregnancy loss following a positive pregnancy diagnosis before Day 90 of gestation) was higher in control cows (OR = 1.42) than in vaccinated cows. The final study population consisted of 336 cows after the second round of vaccination. According to the odds ratios, vaccinated C. burnetii seronegative cows were less likely to be subfertile (> 3 AI) (OR = 0.4) compared to non-vaccinated seronegative animals, and the likelihood of early fetal loss was lower in vaccinated C. burnetii seropositive animals (OR = 0.3) compared to non-vaccinated seronegative cows. Seropositivity to C. burnetii was positively related to twin pregnancy after the two rounds of vaccination (OR = 2.1 and 3.5, respectively). These results indicate that two consecutive vaccination rounds against C. burnetii in advanced gestation reduce subfertility and early fetal loss in dairy cows.

  2. Spread of Coxiella burnetii between dairy cattle herds in an enzootic region: modelling contributions of airborne transmission and trade.

    PubMed

    Pandit, Pranav; Hoch, Thierry; Ezanno, Pauline; Beaudeau, François; Vergu, Elisabeta

    2016-04-05

    Q fever, a worldwide zoonotic disease caused by Coxiella burnetii, is a looming concern for livestock and public health. Epidemiological features of inter-herd transmission of C. burnetii in cattle herds by wind and trade of cows are poorly understood. We present a novel dynamic spatial model describing the inter-herd regional spread of C. burnetii in dairy cattle herds, quantifying the ability of airborne transmission and animal trade in C. burnetii propagation in an enzootic region. Among all the new herd infections, 92% were attributed to airborne transmission and the rest to cattle trade. Infections acquired following airborne transmission were shown to cause relatively small and ephemeral intra-herd outbreaks. On the contrary, disease-free herds purchasing an infectious cow experienced significantly higher intra-herd prevalence. The results also indicated that, for short duration, both transmission routes were independent from each other without any synergistic effect. The model outputs applied to the Finistère department in western France showed satisfactory sensitivity (0.71) and specificity (0.80) in predicting herd infection statuses at the end of one year in a neighbourhood of 3 km around expected incident herds, when compared with data. The model developed here thus provides important insights into the spread of C. burnetii between dairy cattle herds and paves the way for implementation and assessment of control strategies.

  3. Spread of Coxiella burnetii between dairy cattle herds in an enzootic region: modelling contributions of airborne transmission and trade.

    PubMed

    Pandit, Pranav; Hoch, Thierry; Ezanno, Pauline; Beaudeau, François; Vergu, Elisabeta

    2016-01-01

    Q fever, a worldwide zoonotic disease caused by Coxiella burnetii, is a looming concern for livestock and public health. Epidemiological features of inter-herd transmission of C. burnetii in cattle herds by wind and trade of cows are poorly understood. We present a novel dynamic spatial model describing the inter-herd regional spread of C. burnetii in dairy cattle herds, quantifying the ability of airborne transmission and animal trade in C. burnetii propagation in an enzootic region. Among all the new herd infections, 92% were attributed to airborne transmission and the rest to cattle trade. Infections acquired following airborne transmission were shown to cause relatively small and ephemeral intra-herd outbreaks. On the contrary, disease-free herds purchasing an infectious cow experienced significantly higher intra-herd prevalence. The results also indicated that, for short duration, both transmission routes were independent from each other without any synergistic effect. The model outputs applied to the Finistère department in western France showed satisfactory sensitivity (0.71) and specificity (0.80) in predicting herd infection statuses at the end of one year in a neighbourhood of 3 km around expected incident herds, when compared with data. The model developed here thus provides important insights into the spread of C. burnetii between dairy cattle herds and paves the way for implementation and assessment of control strategies. PMID:27048416

  4. High prevalence and two dominant host-specific genotypes of Coxiella burnetii in U.S. milk

    PubMed Central

    2014-01-01

    Background Coxiella burnetii causes Q fever in humans and Coxiellosis in animals; symptoms range from general malaise to fever, pneumonia, endocarditis and death. Livestock are a significant source of human infection as they shed C. burnetii cells in birth tissues, milk, urine and feces. Although prevalence of C. burnetii is high, few Q fever cases are reported in the U.S. and we have a limited understanding of their connectedness due to difficulties in genotyping. Here, we develop canonical SNP genotyping assays to evaluate spatial and temporal relationships among C. burnetii environmental samples and compare them across studies. Given the genotypic diversity of historical collections, we hypothesized that the current enzootic of Coxiellosis is caused by multiple circulating genotypes. We collected A) 23 milk samples from a single bovine herd, B) 134 commercial bovine and caprine milk samples from across the U.S., and C) 400 bovine and caprine samples from six milk processing plants over three years. Results We detected C. burnetii DNA in 96% of samples with no variance over time. We genotyped 88.5% of positive samples; bovine milk contained only a single genotype (ST20) and caprine milk was dominated by a second type (mostly ST8). Conclusions The high prevalence and lack of genotypic diversity is consistent with a model of rapid spread and persistence. The segregation of genotypes between host species is indicative of species-specific adaptations or dissemination barriers and may offer insights into the relative lack of human cases and characterizing genotypes. PMID:24533573

  5. Modulation of the host transcriptome by Coxiella burnetii nuclear effector Cbu1314.

    PubMed

    Weber, Mary M; Faris, Robert; McLachlan, Juanita; Tellez, Andres; Wright, William U; Galvan, Gloria; Luo, Zhao-Qing; Samuel, James E

    2016-05-01

    Coxiella burnetii is a Gram-negative, obligate intracellular pathogen that directs the formation of a parasitophorous vacuole derived from the host lysosomal network. Biogenesis and maintenance of this replicative compartment is dependent on bacterial protein synthesis and results in differential expression of specific host genes. However, the mechanisms by which the pathogen induces changes in the host transcriptome is poorly understood. In the current study we identified a Dot/Icm secreted effector, Cbu1314, which encodes two nuclear localization signals that are required for nuclear localization and association with host chromatin. Chromatin immunoprecipitation (ChIP) and deep sequencing revealed that Cbu1314 associated with host genes involved in transcription, cell signaling, and the immune response. RNA sequencing of cells overexpressing Cbu1314 demonstrated that Cbu1314 modulates the host transcriptome and these transcriptional changes required a functional nuclear localization signal. Of the differentially expressed genes, sixteen were also identified as Cbu1314 targets using ChIP sequencing. Collectively these results suggest that Cbu1314 associates with host chromatin and plays a role in modulating the host transcriptome. PMID:26827929

  6. Analysis of the O-antigen biosynthesis regions of phase II isolates of Coxiella burnetii.

    PubMed

    Denison, Amy M; Massung, Robert F; Thompson, Herbert A

    2007-02-01

    The O-antigen-encoding region in the genomes of 14 isolates of Coxiella burnetii was examined by PCR. Five phase I isolates (Nine Mile clone 7, KAV, Ohio, Henzerling RSA 343, Q173) were analyzed and no deletions were detected. Two other isolates of unknown phase (Scottish, WAV) were examined, but no deletions were detected. In contrast, RSA 514 and three phase II isolates (Nine Mile phase II clone 4, Nine Mile phase II clone 1, Nine Mile Baca) contained large deletions, and the latter two were further characterized by DNA sequencing. Three other phase II isolates (Henzerling RSA 331, M44, Australian QD) contained no apparent deletions. Reactivity to phase I- and phase II-specific antibodies by immunofluorescence assay was used to further characterize isolates. Selected ORFs in Australian QD and M44 DNA were sequenced to detect mutations, and no significant changes were found. Australian QD RNA was examined by reverse transcriptase-PCR specific to the four ORFs hypothesized to encode the O-antigen sugar virenose, which this isolate has been shown to lack, as well as one that is predicted to encode part of the O-antigen ABC transporter. Each of these five genes was found to be expressed.

  7. Identification of Novel Coxiella burnetii Icm/Dot Effectors and Genetic Analysis of Their Involvement in Modulating a Mitogen-Activated Protein Kinase Pathway

    PubMed Central

    Lifshitz, Ziv; Burstein, David; Schwartz, Kierstyn; Shuman, Howard A.; Pupko, Tal

    2014-01-01

    Coxiella burnetii, the causative agent of Q fever, is a human intracellular pathogen that utilizes the Icm/Dot type IVB secretion system to translocate effector proteins into host cells. To identify novel C. burnetii effectors, we applied a machine-learning approach to predict C. burnetii effectors, and examination of 20 such proteins resulted in the identification of 13 novel effectors. To determine whether these effectors, as well as several previously identified effectors, modulate conserved eukaryotic pathways, they were expressed in Saccharomyces cerevisiae. The effects on yeast growth were examined under regular growth conditions and in the presence of caffeine, a known modulator of the yeast cell wall integrity (CWI) mitogen-activated protein (MAP) kinase pathway. In the presence of caffeine, expression of the effectors CBU0885 and CBU1676 caused an enhanced inhibition of yeast growth, and the growth inhibition of CBU0388 was suppressed. Furthermore, analysis of synthetic lethality effects and examination of the activity of the CWI MAP kinase transcription factor Rlm1 indicated that CBU0388 enhances the activation of this MAP kinase pathway in yeast, while CBU0885 and CBU1676 abolish this activation. Additionally, coexpression of CBU1676 and CBU0388 resulted in mutual suppression of their inhibition of yeast growth. These results strongly indicate that these three effectors modulate the CWI MAP kinase pathway in yeast. Moreover, both CBU1676 and CBU0885 were found to contain a conserved haloacid dehalogenase (HAD) domain, which was found to be required for their activity. Collectively, our results demonstrate that MAP kinase pathways are most likely targeted by C. burnetii Icm/Dot effectors. PMID:24958706

  8. Isolation from Animal Tissue and Genetic Transformation of Coxiella burnetii Are Facilitated by an Improved Axenic Growth Medium▿

    PubMed Central

    Omsland, Anders; Beare, Paul A.; Hill, Joshua; Cockrell, Diane C.; Howe, Dale; Hansen, Bryan; Samuel, James E.; Heinzen, Robert A.

    2011-01-01

    We recently described acidified citrate cysteine medium (ACCM), which supports host cell-free (axenic) growth of Coxiella burnetii. After 6 days of incubation, greater than 3 logs of growth was achieved with the avirulent Nine Mile phase II (NMII) strain. Here, we describe modified ACCM and culture conditions that support improved growth of C. burnetii and their use in genetic transformation and pathogen isolation from tissue samples. ACCM was modified by replacing fetal bovine serum with methyl-β-cyclodextrin to generate ACCM-2. Cultivation of NMII in ACCM-2 with moderate shaking and in 2.5% oxygen yielded 4 to 5 logs of growth over 7 days. Similar growth was achieved with the virulent Nine Mile phase I and G isolates of C. burnetii. Colonies that developed after 6 days of growth in ACCM-2 agarose were approximately 0.5 mm in diameter, roughly 5-fold larger than those formed in ACCM agarose. By electron microscopy, colonies consisted primarily of the C. burnetii small cell variant morphological form. NMII was successfully cultured in ACCM-2 when medium was inoculated with as little as 10 genome equivalents contained in tissue homogenates from infected SCID mice. A completely axenic C. burnetii genetic transformation system was developed using ACCM-2 that allowed isolation of transformants in about 2 1/2 weeks. Transformation experiments demonstrated clonal populations in colonies and a transformation frequency of approximately 5 × 10−5. Cultivation in ACCM-2 will accelerate development of C. burnetii genetic tools and provide a sensitive means of primary isolation of the pathogen from Q fever patients. PMID:21478315

  9. Survey of Laboratory Animal Technicians in the United States for Coxiella burnetii Antibodies and Exploration of Risk Factors for Exposure

    PubMed Central

    Whitney, Ellen A Spotts; Massung, Robert F; Kersh, Gilbert J; Fitzpatrick, Kelly A; Mook, Deborah M; Taylor, Douglas K; Huerkamp, Michael J; Vakili, Jessica C; Sullivan, Patrick J; Berkelman, Ruth L

    2013-01-01

    Little is known about the prevalence of zoonotic infections among laboratory animal care technicians (LAT). Q fever, a disease caused by Coxiella burnetii, is a known occupational hazard for persons caring for livestock. We sought to determine the seroprevalence of C. burnetii antibodies among LAT and to identify risk factors associated with C. burnetii seropositivity. A survey was administered and serum samples collected from a convenience sample of 97 LAT. Samples were screened by using a Q fever IgG ELISA. Immunofluorescent antibody assays for phase I and phase II IgG were used to confirm the status of samples that were positive or equivocal by ELISA; positive samples were titered to endpoint. Antibodies against C. burnetii were detected in 6 (6%) of the 97 respondents. In our sample of LAT, seropositivity to C. burnetii was therefore twice as high in LAT as compared with the general population. Age, sex, and working with sheep regularly were not associated with seropositivity. Risk factors associated with seropositivity included breeding cattle within respondent's research facility, any current job contact with waste from beef cattle or goats, and exposure to animal waste during previous jobs or outside of current job duties. Only 15% of responding LAT reported being aware that sheep, goats, and cattle can transmit Q fever. Research facilities that use cattle or goats should evaluate their waste-management practices and educational programs in light of these findings. Additional efforts are needed to increase awareness among LAT regarding Q fever and heightened risk of exposure to infectious materials. Physicians should consider the risk of infection with C. burnetii when treating LAT with potential occupational exposures. PMID:24351760

  10. Agglutinins to Coxiella burnetii and Brucella spp, with particular reference to Brucella canis, in wild animals of southern Texas.

    PubMed

    Randhawa, A S; Kelly, V P; Baker, E F

    1977-11-01

    The prevalence of agglutinins to Coxiella burnetii and Brucella spp, particularly Brucella canis, was determined in 269 wild animals (14 species) in southern Texas. Serologic evidence of coxiellosis and brucellosis, including B canis infection, was shown for coyotes, raccoons, opossums, badgers, jackrabbits, and feral hogs. Using the microagglutination test, the seroprevalence of C burnetii, phases I and II (titer greater than or equal to 4) was 4.1 and 27.9%, respectively. For brucella agglutinins, prevalence rates were 7.1, 8.9, and 6.7%, as determined by the brucellosis card test, the rapid slide agglutination test, and the salt 2-mercaptoethanol tube agglutination (titer greater than or equal to 50) test, respectively.

  11. Coxiella burnetii Infection in a Community Operating a Large-Scale Cow and Goat Dairy, Missouri, 2013.

    PubMed

    Biggs, Holly M; Turabelidze, George; Pratt, Drew; Todd, Suzanne R; Jacobs-Slifka, Kara; Drexler, Naomi A; McCurdy, Gail; Lloyd, Jennifer; Evavold, Charles L; Fitzpatrick, Kelly A; Priestley, Rachael A; Singleton, Joseph; Sun, David; Tang, Minh; Kato, Cecilia; Kersh, Gilbert J; Anderson, Alicia

    2016-03-01

    Coxiella burnetii is a zoonotic pathogen that causes Q fever in humans and is transmitted primarily from infected goats, sheep, or cows. Q fever typically presents as an acute febrile illness; however, individuals with certain predisposing conditions, including cardiac valvulopathy, are at risk for chronic Q fever, a serious manifestation that may present as endocarditis. In response to a cluster of Q fever cases detected by public health surveillance, we evaluated C. burnetii infection in a community that operates a large-scale cow and goat dairy. A case was defined as an individual linked to the community with a C. burnetii phase II IgG titer ≥ 128. Of 135 participants, 47 (35%) cases were identified. Contact with or close proximity to cows, goats, and their excreta was associated with being a case (relative risk 2.7, 95% confidence interval 1.3-5.3). Cases were also identified among individuals without cow or goat contact and could be related to windborne spread or tracking of C. burnetii on fomites within the community. A history of injection drug use was reported by 26/130 (20%) participants; follow-up for the presence of valvulopathy and monitoring for development of chronic Q fever may be especially important among this population.

  12. Molecular characterization by MLVA of Coxiella burnetii strains infecting dairy cows and goats of north-eastern Italy.

    PubMed

    Ceglie, Letizia; Guerrini, Eulalia; Rampazzo, Erika; Barberio, Antonio; Tilburg, Jeroen J H C; Hagen, Ferry; Lucchese, Laura; Zuliani, Federica; Marangon, Stefano; Natale, Alda

    2015-01-01

    Q fever is a worldwide zoonotic disease caused by Coxiella burnetii (C. burnetii), an obligate intracellular bacterium. In ruminants, shedding into the environment mainly occurs during parturition or abortion, but the bacterium is shed also in milk, vaginal mucus, stools and urine. In Italy few surveys have been conducted and reported seroprevalence values ranged between 10% and 60%, even if few human cases have been described. Genotyping of bacteria is crucial for enhancing diagnostic methods and for epidemiological surveillance. The objective of this study was to investigate genotypic differences of C. burnetii genotypes directly in 34 samples, collected during a 3-years survey among 11 dairy cattle and 11 goat farms in the north-eastern part of Italy using a 6-locus multiple loci variable number of tandem repeat analysis (MLVA) method. The samples analysed included 13 bulk tank milk (BTM), 6 individual milk, 11 vaginal swabs and 4 foetal spleens. MLVA-type 2 was determined as the most prevalent in cattle in this study. C. burnetii strains circulating in the studied cattle population are very similar to genotypes previously described, while genotypes from goats showed an important variability. Further investigation are needed to understand the reason of this pattern.

  13. [A 42-year-old farmer with nonspecific leucocytosis and elevated transaminases. Acute septic reaction in Coxiella burnetii infection].

    PubMed

    Hempel, U; Schäffler, A; Salzberger, B; Rümmele, P; Schölmerich, J

    2008-06-01

    We report about a 42-year-old farmer with leucocytosis, elevation of transaminases and liver cirrhosis as an underlying condition. The diagnosis of Q fever hepatitis was made through liver biopsy and serology. Under therapy with doxycycline, transaminases initially increased again; after switching to ciprofloxacin, the patient could be discharged 3 weeks after admission. Q fever is caused by Coxiella burnetii. The most frequent acute manifestation is a self-limiting flu-like illness. Chronic Q fever mostly presents as endocarditis. The diagnosis is made through histology ("doughnut" granulomas), PCR, serology (acute: anti-phase II antibodies, chronic: anti-phase I antibodies) and culture. Standard therapy is doxycycline.

  14. A Screen of Coxiella burnetii Mutants Reveals Important Roles for Dot/Icm Effectors and Host Autophagy in Vacuole Biogenesis

    PubMed Central

    Newton, Hayley J.; Kohler, Lara J.; McDonough, Justin A.; Temoche-Diaz, Morayma; Crabill, Emerson; Hartland, Elizabeth L.; Roy, Craig R.

    2014-01-01

    Coxiella burnetii is an intracellular pathogen that replicates in a lysosome-derived vacuole. The molecular mechanisms used by this bacterium to create a pathogen-occupied vacuole remain largely unknown. Here, we conducted a visual screen on an arrayed library of C. burnetii NMII transposon insertion mutants to identify genes required for biogenesis of a mature Coxiella-containing vacuole (CCV). Mutants defective in Dot/Icm secretion system function or the PmrAB regulatory system were incapable of intracellular replication. Several mutants with intracellular growth defects were found to have insertions in genes encoding effector proteins translocated into host cells by the Dot/Icm system. These included mutants deficient in the effector proteins Cig57, CoxCC8 and Cbu1754. Mutants that had transposon insertions in genes important in central metabolism or encoding tRNA modification enzymes were identified based on the appearance filamentous bacteria intracellularly. Lastly, mutants that displayed a multi-vacuolar phenotype were identified. All of these mutants had a transposon insertion in the gene encoding the effector protein Cig2. Whereas vacuoles containing wild type C. burnetii displayed robust accumulation of the autophagosome protein LC3, the vacuoles formed by the cig2 mutant did not contain detectible amounts of LC3. Furthermore, interfering with host autophagy during infection by wild type C. burnetii resulted in a multi-vacuolar phenotype similar to that displayed by the cig2 mutant. Thus, a functional Cig2 protein is important for interactions between the CCV and host autophagosomes and this drives a process that enhances the fusogenic properties of this pathogen-occupied organelle. PMID:25080348

  15. The natural infection of birds and ticks feeding on birds with Rickettsia spp. and Coxiella burnetii in Slovakia.

    PubMed

    Berthová, Lenka; Slobodník, Vladimír; Slobodník, Roman; Olekšák, Milan; Sekeyová, Zuzana; Svitálková, Zuzana; Kazimírová, Mária; Špitalská, Eva

    2016-03-01

    Ixodid ticks (Acari: Ixodidae) are known as primary vectors of many pathogens causing diseases in humans and animals. Ixodes ricinus is a common ectoparasite in Europe and birds are often hosts of subadult stages of the tick. From 2012 to 2013, 347 birds belonging to 43 species were caught and examined for ticks in three sites of Slovakia. Ticks and blood samples from birds were analysed individually for the presence of Rickettsia spp. and Coxiella burnetii by PCR-based methods. Only I. ricinus was found to infest birds. In total 594 specimens of bird-attached ticks were collected (451 larvae, 142 nymphs, 1 female). Altogether 37.2% (16/43) of bird species were infested by ticks and some birds carried more than one tick. The great tit, Parus major (83.8%, 31/37) was the most infested species. In total, 6.6 and 2.7% of bird-attached ticks were infected with Rickettsia spp. and C. burnetii, respectively. Rickettsia helvetica predominated (5.9%), whereas R. monacensis (0.5%) was only sporadically detected. Coxiella burnetii was detected in 0.9%, Rickettsia spp. in 8.9% and R. helvetica in 4.2% of bird blood samples. The great tit was the bird species most infested with I. ricinus, carried R. helvetica and C. burnetti positive tick larvae and nymphs and was found to be rickettsaemic in its blood. Further studies are necessary to define the role of birds in the circulation of rickettsiae and C. burnetii in natural foci.

  16. A screen of Coxiella burnetii mutants reveals important roles for Dot/Icm effectors and host autophagy in vacuole biogenesis.

    PubMed

    Newton, Hayley J; Kohler, Lara J; McDonough, Justin A; Temoche-Diaz, Morayma; Crabill, Emerson; Hartland, Elizabeth L; Roy, Craig R

    2014-07-01

    Coxiella burnetii is an intracellular pathogen that replicates in a lysosome-derived vacuole. The molecular mechanisms used by this bacterium to create a pathogen-occupied vacuole remain largely unknown. Here, we conducted a visual screen on an arrayed library of C. burnetii NMII transposon insertion mutants to identify genes required for biogenesis of a mature Coxiella-containing vacuole (CCV). Mutants defective in Dot/Icm secretion system function or the PmrAB regulatory system were incapable of intracellular replication. Several mutants with intracellular growth defects were found to have insertions in genes encoding effector proteins translocated into host cells by the Dot/Icm system. These included mutants deficient in the effector proteins Cig57, CoxCC8 and Cbu1754. Mutants that had transposon insertions in genes important in central metabolism or encoding tRNA modification enzymes were identified based on the appearance filamentous bacteria intracellularly. Lastly, mutants that displayed a multi-vacuolar phenotype were identified. All of these mutants had a transposon insertion in the gene encoding the effector protein Cig2. Whereas vacuoles containing wild type C. burnetii displayed robust accumulation of the autophagosome protein LC3, the vacuoles formed by the cig2 mutant did not contain detectible amounts of LC3. Furthermore, interfering with host autophagy during infection by wild type C. burnetii resulted in a multi-vacuolar phenotype similar to that displayed by the cig2 mutant. Thus, a functional Cig2 protein is important for interactions between the CCV and host autophagosomes and this drives a process that enhances the fusogenic properties of this pathogen-occupied organelle.

  17. Backbone and side-chain ¹H, ¹³C and ¹⁵N assignments of the PPIase domain of macrophage infectivity potentiator (Mip) protein from Coxiella burnetii.

    PubMed

    Tse, Man-Kit; Cheung, Stanley K K; Ke, Yi-hong; Lau, Candy C Y; Sze, Kong-Hung; Yuen, Kwok-Yung

    2014-04-01

    Coxiella burnetii is an obligate intracellular gram-negative bacterium uniquely evolved to thrive in the inhospitable phagolysosome of macrophage. C. burnetii causes Q fever in humans and animals, which is emerging as a global public health concern. It is highly infectious and designated as a category B biowarfare agent because of its ubiquitous nature, abundant natural reservoirs, high resistance to environmental conditions, ease of transmission and low infectious dose. The lack of knowledge and awareness of C. burnetii leads to under-reporting and under-diagnosing of Q fever cases. Therefore, further understanding of the interactions between the infected host and the bacteria is necessary. C. burnetii macrophage infectivity potentiator (cb-Mip) is a secreted protein of 230 amino acids involving in intracellular survival of the pathogen. cb-Mip belongs to the family of FK506 binding protein, which possesses peptidyl-prolyl cis/trans isomerase (PPIase) activity. Besides acting as a PPIase, Mip protein homolog has been identified as virulence factor of many intracellular pathogenic microorganisms. In the present study, we report the near complete resonance assignments of the PPIase domain-containing region of Mip protein of C. burnetii. Secondary structure prediction based on chemical shift index analysis indicates that the protein adopts a predominately beta-strand structure, which is consistent with the crystal structure of homologous Mip protein in Legionella pneumophila.

  18. Prevalence and spatial distribution of antibodies to bovine viral diarrhea virus and Coxiella burnetii in white-tailed deer (Odocoileus virginianus) in New York and Pennsylvania.

    PubMed

    Kirchgessner, Megan S; Dubovi, Edward J; Porter, William F; Zylich, Nancy C; Whipps, Christopher M

    2012-09-01

    Significant pathogens of domestic livestock and public-health related pathogens, such as bovine viral diarrhea virus (BVDV) and Coxiella burnetii, are commonly diagnosed in some wildlife species. BVDV is an economically important pathogen of domestic bovids and Coxiella burnetii is a highly infectious zoonotic bacterium. As a result of recent shifting patterns of disease, it is critical that baseline information regarding the status of both significant pathogens of domestic livestock and public-health related pathogens are established for commonly encountered wildlife such as white-tailed deer (Odocoileus virginianus). White-tailed deer are susceptible to both BVDV and C. burnetii infection, and the purpose of this study was to investigate for the presence of antibodies to these two pathogens in New York and Pennsylvania white-tailed deer. Exposure to BVDV and C. burnetii was determined using sera collected from 333 (219 males and 114 females) wild white-tailed deer in New York and 291 (130 males and 161 females) wild white-tailed deer from Pennsylvania. Samples were collected from hunter-harvested deer in central New York State in 2009 and live-captured deer in Pennsylvania in 2010. Sera were screened for anti-BVDV antibodies via a commercial blocking BVDV enzyme-linked immunosorbent assay. Coxiella burnetii phase II whole-cell antigen-coated slides were used to screen sera via an indirect microimmunofluorescence assay. Antibody prevalence was compared by sex class and location of collection. Deer in New York had higher antibody prevalence to BVDV (6.01%) than did deer in Pennsylvania (0.34%). Conversely, C. burnetii phase II antibodies were more common in Pennsylvania (20.96%) than in New York (14.41%). No statistically significant difference between locations was observed in either BVDV or C. burnetii antibody prevalence when data were analyzed by sex-class. Overall, C. burnetii seroprevalence was not significantly higher in Pennsylvania than in New York.

  19. [Detection of Coxiella burnetii in dairy cattle bulk tank milk and single tank milk samples by confirmatory testing].

    PubMed

    Hilbert, Angela; Andres, Tatjana; Werner, Ralf; Wehr, Roswitha; Fröhlich, Andreas; Conraths, Franz J; Henning, Klaus

    2015-01-01

    Q fever is a worldwide zoonotic disease caused by the pathogen Coxiella (C.) burnetii. A wide range of animal species is susceptible to this intracellular bacterium with great importance in ruminants. Human infections occur mainly by airborne transmission. C burnetii was detected in animal products such as raw milk, raw-milk cheese and butter prepared from raw milk as well as in the meat of infected animals. In cattle milk, the pathogen was detected up to 13 months after calving. The risk of human foodborne C. Burnetii infection is still considered to be low, but cannot be completely ruled out and remains under discussion. The aim of this study was to compare different laboratory diagnostic methods for C. burnetii in milk sample. The bulk tank and individual milk samples were sent and studied at the National Reference Laboratory for Q-fever in the context of confirmatory laboratory testing after clinical suspicion or retesting of previously antibody detection was in the analysis of 888 individual milk samples a match of 93.3% (Cohen-kappa). A total of 173 bulk milk samples and 2,807 individual milk samples from bovine herds for the presence of C. burnetii DNA and antibodies were tested against the pathogen. The pathogen was detected in 62.5% of the bulk milk samples and up to 60% in individual milk samples. The highest proportion of positive bulk milks was determined as 68.3% in 2012. In individual milk samples, the highest proportion of seropositive samples was 62.2%.

  20. Coxiella burnetii antibody dynamics in heifers born to vaccinated versus non-vaccinated dams in a chronically infected dairy herd.

    PubMed

    Tutusaus, Joan; Garcia-Ispierto, Irina; López-Gatius, Fernando

    2015-09-01

    This study was designed to compare Coxiella burnetii antibody dynamics in heifers born to vaccinated or non-vaccinated dams in a single high-producing dairy herd chronically infected with the bacterium. Antibody dynamics were examined from birth to the postpartum period in replacement heifers (n = 14) born to non-vaccinated dams (n = 7) or to dams that had been vaccinated on gestation days 171-177 (n = 7) and 192-198. Samples of blood, milk, faeces, vaginal fluid, colostrum and cotyledons (the latter two only at parturition) were obtained in the dams over the period from gestation days 171-177 to postpartum days 91-97. Blood samples were used to detect antibodies against C. burnetii and remaining samples for PCR identification of the bacterium. In their calves/heifers, blood samples for antibody determinations were collected from birth to postpartum at the time points 1-7 and 22-28 days and 3, 6 and 12 months of age; 90-96 and 210-216 days of gestation; and 22-28 days postpartum. All calves were born seronegative for C. burnetii. Irrespective of the shedding status of their mothers (7 were C. burnetii shedders), seroconversion occurred after colostrum intake in all calves born to seropositive cows (n = 9) and in two of three vaccinated seronegative dams. Thereafter antibody titres gradually declined and by 6 months of age all calves were seronegative. Seronegativity persisted until their first postpartum period. These findings indicate that cows vaccinated during advanced pregnancy transfer immunity to their calves via the colostrum. Maternal C. burnetii antibodies in calves persisted for three months in calves born both to seronegative vaccinated and seropositive dams.

  1. Identification of ElpA, a Coxiella burnetii pathotype-specific Dot/Icm type IV secretion system substrate.

    PubMed

    Graham, Joseph G; Winchell, Caylin G; Sharma, Uma M; Voth, Daniel E

    2015-03-01

    Coxiella burnetii causes human Q fever, a zoonotic disease that presents with acute flu-like symptoms and can result in chronic life-threatening endocarditis. In human alveolar macrophages, C. burnetii uses a Dot/Icm type IV secretion system (T4SS) to generate a phagolysosome-like parasitophorous vacuole (PV) in which to replicate. The T4SS translocates effector proteins, or substrates, into the host cytosol, where they mediate critical cellular events, including interaction with autophagosomes, PV formation, and prevention of apoptosis. Over 100 C. burnetii Dot/Icm substrates have been identified, but the function of most remains undefined. Here, we identified a novel Dot/Icm substrate-encoding open reading frame (CbuD1884) present in all C. burnetii isolates except the Nine Mile reference isolate, where the gene is disrupted by a frameshift mutation, resulting in a pseudogene. The CbuD1884 protein contains two transmembrane helices (TMHs) and a coiled-coil domain predicted to mediate protein-protein interactions. The C-terminal region of the protein contains a predicted Dot/Icm translocation signal and was secreted by the T4SS, while the N-terminal portion of the protein was not secreted. When ectopically expressed in eukaryotic cells, the TMH-containing N-terminal region of the CbuD1884 protein trafficked to the endoplasmic reticulum (ER), with the C terminus dispersed nonspecifically in the host cytoplasm. This new Dot/Icm substrate is now termed ElpA (ER-localizing protein A). Full-length ElpA triggered substantial disruption of ER structure and host cell secretory transport. These results suggest that ElpA is a pathotype-specific T4SS effector that influences ER function during C. burnetii infection.

  2. Coxiella burnetii antibody dynamics in heifers born to vaccinated versus non-vaccinated dams in a chronically infected dairy herd.

    PubMed

    Tutusaus, Joan; Garcia-Ispierto, Irina; López-Gatius, Fernando

    2015-09-01

    This study was designed to compare Coxiella burnetii antibody dynamics in heifers born to vaccinated or non-vaccinated dams in a single high-producing dairy herd chronically infected with the bacterium. Antibody dynamics were examined from birth to the postpartum period in replacement heifers (n = 14) born to non-vaccinated dams (n = 7) or to dams that had been vaccinated on gestation days 171-177 (n = 7) and 192-198. Samples of blood, milk, faeces, vaginal fluid, colostrum and cotyledons (the latter two only at parturition) were obtained in the dams over the period from gestation days 171-177 to postpartum days 91-97. Blood samples were used to detect antibodies against C. burnetii and remaining samples for PCR identification of the bacterium. In their calves/heifers, blood samples for antibody determinations were collected from birth to postpartum at the time points 1-7 and 22-28 days and 3, 6 and 12 months of age; 90-96 and 210-216 days of gestation; and 22-28 days postpartum. All calves were born seronegative for C. burnetii. Irrespective of the shedding status of their mothers (7 were C. burnetii shedders), seroconversion occurred after colostrum intake in all calves born to seropositive cows (n = 9) and in two of three vaccinated seronegative dams. Thereafter antibody titres gradually declined and by 6 months of age all calves were seronegative. Seronegativity persisted until their first postpartum period. These findings indicate that cows vaccinated during advanced pregnancy transfer immunity to their calves via the colostrum. Maternal C. burnetii antibodies in calves persisted for three months in calves born both to seronegative vaccinated and seropositive dams. PMID:26551423

  3. Circulation of Coxiella burnetii in a Naturally Infected Flock of Dairy Sheep: Shedding Dynamics, Environmental Contamination, and Genotype Diversity.

    PubMed

    Joulié, A; Laroucau, K; Bailly, X; Prigent, M; Gasqui, P; Lepetitcolin, E; Blanchard, B; Rousset, E; Sidi-Boumedine, K; Jourdain, E

    2015-10-01

    Q fever is a worldwide zoonosis caused by Coxiella burnetii. Domestic ruminants are considered to be the main reservoir. Sheep, in particular, may frequently cause outbreaks in humans. Because within-flock circulation data are essential to implementing optimal management strategies, we performed a follow-up study of a naturally infected flock of dairy sheep. We aimed to (i) describe C. burnetii shedding dynamics by sampling vaginal mucus, feces, and milk, (ii) assess circulating strain diversity, and (iii) quantify barn environmental contamination. For 8 months, we sampled vaginal mucus and feces every 3 weeks from aborting and nonaborting ewes (n=11 and n=26, respectively); for lactating females, milk was obtained as well. We also sampled vaginal mucus from nine ewe lambs. Dust and air samples were collected every 3 and 6 weeks, respectively. All samples were screened using real-time PCR, and strongly positive samples were further analyzed using quantitative PCR. Vaginal and fecal samples with sufficient bacterial burdens were then genotyped by multiple-locus variable-number tandem-repeat analysis (MLVA) using 17 markers. C. burnetii burdens were higher in vaginal mucus and feces than in milk, and they peaked in the first 3 weeks postabortion or postpartum. Primiparous females and aborting females tended to shed C. burnetii longer and have higher bacterial burdens than nonaborting and multiparous females. Six genotype clusters were identified; they were independent of abortion status, and within-individual genotype diversity was observed. C. burnetii was also detected in air and dust samples. Further studies should determine whether the within-flock circulation dynamics observed here are generalizable.

  4. Molecular method for the characterization of Coxiella burnetii from clinical and environmental samples: variability of genotypes in Spain

    PubMed Central

    2012-01-01

    Background Coxiella burnetii is a highly clonal microorganism which is difficult to culture, requiring BSL3 conditions for its propagation. This leads to a scarce availability of isolates worldwide. On the other hand, published methods of characterization have delineated up to 8 different genomic groups and 36 genotypes. However, all these methodologies, with the exception of one that exhibited limited discriminatory power (3 genotypes), rely on performing between 10 and 20 PCR amplifications or sequencing long fragments of DNA, which make their direct application to clinical samples impracticable and leads to a scarce accessibility of data on the circulation of C. burnetii genotypes. Results To assess the variability of this organism in Spain, we have developed a novel method that consists of a multiplex (8 targets) PCR and hybridization with specific probes that reproduce the previous classification of this organism into 8 genomic groups, and up to 16 genotypes. It allows for a direct characterization from clinical and environmental samples in a single run, which will help in the study of the different genotypes circulating in wild and domestic cycles as well as from sporadic human cases and outbreaks. The method has been validated with reference isolates. A high variability of C. burnetii has been found in Spain among 90 samples tested, detecting 10 different genotypes, being those adaA negative associated with acute Q fever cases presenting as fever of intermediate duration with liver involvement and with chronic cases. Genotypes infecting humans are also found in sheep, goats, rats, wild boar and ticks, and the only genotype found in cattle has never been found among our clinical samples. Conclusions This newly developed methodology has permitted to demonstrate that C. burnetii is highly variable in Spain. With the data presented here, cattle seem not to participate in the transmission of C. burnetii to humans in the samples studied, while sheep, goats, wild

  5. The Type IV Secretion System Effector Protein CirA Stimulates the GTPase Activity of RhoA and Is Required for Virulence in a Mouse Model of Coxiella burnetii Infection.

    PubMed

    Weber, Mary M; Faris, Robert; van Schaik, Erin J; McLachlan, Juanita Thrasher; Wright, William U; Tellez, Andres; Roman, Victor A; Rowin, Kristina; Case, Elizabeth Di Russo; Luo, Zhao-Qing; Samuel, James E

    2016-09-01

    Coxiella burnetii, the etiological agent of Q fever in humans, is an intracellular pathogen that replicates in an acidified parasitophorous vacuole derived from host lysosomes. Generation of this replicative compartment requires effectors delivered into the host cell by the Dot/Icm type IVb secretion system. Several effectors crucial for C. burnetii intracellular replication have been identified, but the host pathways coopted by these essential effectors are poorly defined, and very little is known about how spacious vacuoles are formed and maintained. Here we demonstrate that the essential type IVb effector, CirA, stimulates GTPase activity of RhoA. Overexpression of CirA in mammalian cells results in cell rounding and stress fiber disruption, a phenotype that is rescued by overexpression of wild-type or constitutively active RhoA. Unlike other effector proteins that subvert Rho GTPases to modulate uptake, CirA is the first effector identified that is dispensable for uptake and instead recruits Rho GTPase to promote biogenesis of the bacterial vacuole. Collectively our results highlight the importance of CirA in coopting host Rho GTPases for establishment of Coxiella burnetii infection and virulence in mammalian cell culture and mouse models of infection. PMID:27324482

  6. Absence of serological evidence of Rickettsia spp., Bartonella spp., Ehrlichia spp. and Coxiella burnetii infections in American Samoa.

    PubMed

    Lau, Colleen; Musso, Didier; Fournier, Pierre-Edouard; Parola, Philippe; Raoult, Didier; Weinstein, Philip

    2016-07-01

    Little is known about the epidemiology of zoonotic diseases in American Samoa (Pacific). A review of literature did not identify any published information on human Rickettsia spp., Bartonella spp., Ehrlichia spp. or Coxiella burnetii infections in this country. To determine the presence of these diseases, we conducted a serosurvey of American Samoans. The presence of immunoglobulin G antibodies against Rickettsia felis, Rickettsia typhi, Rickettsia conorii, C. burnetii, Bartonella henselae, Bartonella quintana, and Ehrlichia chaffeensis was evaluated by indirect immunofluorescence assay in sera from 197 American Samoan adults. None of the samples had antibodies at a significant level against Rickettsia spp., Bartonella spp., Ehrlichia spp. or C. burnetii (seroprevalence 0%; one-tailed 95% CI 0-1.86%). We cannot conclude that these pathogens are absent in American Samoa but, if present, their prevalence is probably very low. Q fever has been reported worldwide except in New Zealand and French Polynesia; these new data suggest that the prevalence of Q fever is likely to be very low in the Pacific Islands. PMID:26965788

  7. Seroprevalence for Coxiella burnetii, Francisella tularensis, Brucella abortus and Brucella melitensis in Austrian adults: a cross-sectional survey among military personnel and civilians.

    PubMed

    Tobudic, Selma; Nedomansky, Klara; Poeppl, Wolfgang; Müller, Maria; Faas, Angelus; Mooseder, Gerhard; Allerberger, Franz; Stanek, Gerold; Burgmann, Heinz

    2014-04-01

    The prevalence of Coxiella burnetii, Francisella tularensis, Brucella abortus, and Brucella melitensis infections in Austria and the exposure risk of military personnel were assessed in an exploratory nationwide cross-sectional seroprevalence survey in 526 healthy adult individuals, 222 of which were soldiers and 304 were civilians. Screening for IgA/IgG antibodies to C. burnetii (Phase I) and IgG/IgM antibodies to C. burnetii (Phase II), and to F. tularensis was done with commercial enzyme-linked immunosorbent assays. To detect antibodies against B. abortus and B. melitensis, an in-house complement fixation test was used. Overall, 11 individuals (2.0%) showed antibodies to C. burnetii, 3 individuals (0.5%) were seropositive for F. tularensis, and one (0.3%) individual was borderline positive. All individuals positive or borderline for F. tularensis tested negative for antibodies against C. burnetii. All individuals tested negative for antibodies against B. melitensis/B. abortus. There were no significant differences between the seroprevalence of C. burnetii and F. tularensis among military personnel and civilians. Our data demonstrate serological evidence of a low rate of exposure to C. burnetii and F. tularensis among the Austrian adult population and military personnel.

  8. Seroepidemiologic survey for Coxiella burnetii among US military personnel deployed to Southwest and Central Asia in 2005.

    PubMed

    Royal, Joseph; Riddle, Mark S; Mohareb, Emad; Monteville, Marshall R; Porter, Chad K; Faix, Dennis J

    2013-11-01

    We used a seroepidemiologic study to estimate Q fever (Coxiella burnetii) seroprevalence, seroincidence, and risk factors for seroconversion in two deployed military populations in 2005. The first study group resided in an area with a known Q fever outbreak history (Al Asad, Iraq). Of this population, 7.2% seroconverted for an incidence rate of 10.6 seroconversions per 1,000 person-months. The second population included personnel transiting through Qatar on mid-deployment leave from southwest/central Asia. In this group, we found 2.1% prevalence with 0.92 seroconversions per 1,000 person-months. However, no significant risk factors for Q fever seroconversion were found in either population.

  9. Vaccination using phase I vaccine is effective to control Coxiella burnetii shedding in infected dairy cattle herds.

    PubMed

    Taurel, Anne-Frieda; Guatteo, Raphaël; Lehebel, Anne; Joly, Alain; Beaudeau, François

    2014-01-01

    The effectiveness of the vaccination of dairy cows combined or not with antibiotics (i.e. oxytetracycline) to control Coxiella burnetii (Cb) shedding at herd level was investigated in 77 Q fever clinically affected herds. In addition to nulliparous heifers' vaccination, one out of the four following medical strategies was randomly assigned to dairy cows in each herd: vaccination (using a phase I vaccine) alone, vaccination combined with oxytetracycline, oxytetracycline alone or nothing. Their effectiveness to reduce Cb load in quarterly samples of bulk tank milk (BTM) and of pooled milk of primiparous (MP) was assessed through logistic hierarchical models. A significant reduction in Cb load was observed in herds where the vaccination of ≥80% of dairy cows was implemented; whereas the use of antibiotics was uneffective. Our findings support the interest of a whole vaccination strategy and provide evidence for decreasing the use of antibiotics in dairy cattle herds.

  10. Transcriptional Profiling of Coxiella burnetii Reveals Extensive Cell Wall Remodeling in the Small Cell Variant Developmental Form.

    PubMed

    Sandoz, Kelsi M; Popham, David L; Beare, Paul A; Sturdevant, Daniel E; Hansen, Bryan; Nair, Vinod; Heinzen, Robert A

    2016-01-01

    A hallmark of Coxiella burnetii, the bacterial cause of human Q fever, is a biphasic developmental cycle that generates biologically, ultrastructurally, and compositionally distinct large cell variant (LCV) and small cell variant (SCV) forms. LCVs are replicating, exponential phase forms while SCVs are non-replicating, stationary phase forms. The SCV has several properties, such as a condensed nucleoid and an unusual cell envelope, suspected of conferring enhanced environmental stability. To identify genetic determinants of the LCV to SCV transition, we profiled the C. burnetii transcriptome at 3 (early LCV), 5 (late LCV), 7 (intermediate forms), 14 (early SCV), and 21 days (late SCV) post-infection of Vero epithelial cells. Relative to early LCV, genes downregulated in the SCV were primarily involved in intermediary metabolism. Upregulated SCV genes included those involved in oxidative stress responses, arginine acquisition, and cell wall remodeling. A striking transcriptional signature of the SCV was induction (>7-fold) of five genes encoding predicted L,D transpeptidases that catalyze nonclassical 3-3 peptide cross-links in peptidoglycan (PG), a modification that can influence several biological traits in bacteria. Accordingly, of cross-links identified, muropeptide analysis showed PG of SCV with 46% 3-3 cross-links as opposed to 16% 3-3 cross-links for LCV. Moreover, electron microscopy revealed SCV with an unusually dense cell wall/outer membrane complex as compared to LCV with its clearly distinguishable periplasm and inner and outer membranes. Collectively, these results indicate the SCV produces a unique transcriptome with a major component directed towards remodeling a PG layer that likely contributes to Coxiella's environmental resistance. PMID:26909555

  11. Effect of a phase I Coxiella burnetii inactivated vaccine on body temperature and milk yield in dairy cows.

    PubMed

    Schulze, L S-Ch; Borchardt, S; Ouellet, V; Heuwieser, W

    2016-01-01

    Q fever is a zoonotic disease caused by Coxiella burnetii. The pathogen is prevalent in ruminants (goats, sheep, cows), which are the main sources of human infection. In the cattle industry around the world, animal (15 to 20%) and herd (38 to 72%) level prevalences of C. burnetii are high. Vaccination of ruminants against Q fever is considered important to prevent spreading of the disease and risk of infection in humans. However, published information on side effects of the Q fever vaccination under field conditions is limited for cows. The objective of this study was to investigate the effect of the phase I C. burnetii inactivated vaccine Coxevac on body temperature and milk yield in dairy cows. In 2 experiments, a total of 508 cows were randomly divided into 2 groups to determine the effect of first vaccination on body temperature and milk yield. The C. burnetii serostatus of all cows was tested before vaccination with an indirect ELISA. The first experiment took place in the teaching and research barn of the Clinic of Animal Reproduction at the Freie Universität Berlin. Temperature was measured vaginally in 10 cows in a crossover design. The second experiment was conducted on a commercial dairy farm. Milk yield of 498 cows was measured 1 wk before and 1 wk after vaccination. In a subset of 41 cows, temperature was measured rectally. In both experiments, body temperature increased significantly after vaccination (1.0 ± 0.9°C and 0.7 ± 0.8°C). A significant difference was also found in body temperature between vaccinated and control cows. Thirty percent of the vaccinated animals in experiment 1 showed reversible swelling at the injection site as a reaction to the vaccination. The results indicate that vaccination against Q fever causes a transient increase of body temperature that peaks in the first 12 to 24h and declines after that. In experiment 2, vaccinated cows (26.8 ± 0.39 kg/d) produced significantly less milk than did control cows (28.2 ± 0.44 kg

  12. Effect of a phase I Coxiella burnetii inactivated vaccine on body temperature and milk yield in dairy cows.

    PubMed

    Schulze, L S-Ch; Borchardt, S; Ouellet, V; Heuwieser, W

    2016-01-01

    Q fever is a zoonotic disease caused by Coxiella burnetii. The pathogen is prevalent in ruminants (goats, sheep, cows), which are the main sources of human infection. In the cattle industry around the world, animal (15 to 20%) and herd (38 to 72%) level prevalences of C. burnetii are high. Vaccination of ruminants against Q fever is considered important to prevent spreading of the disease and risk of infection in humans. However, published information on side effects of the Q fever vaccination under field conditions is limited for cows. The objective of this study was to investigate the effect of the phase I C. burnetii inactivated vaccine Coxevac on body temperature and milk yield in dairy cows. In 2 experiments, a total of 508 cows were randomly divided into 2 groups to determine the effect of first vaccination on body temperature and milk yield. The C. burnetii serostatus of all cows was tested before vaccination with an indirect ELISA. The first experiment took place in the teaching and research barn of the Clinic of Animal Reproduction at the Freie Universität Berlin. Temperature was measured vaginally in 10 cows in a crossover design. The second experiment was conducted on a commercial dairy farm. Milk yield of 498 cows was measured 1 wk before and 1 wk after vaccination. In a subset of 41 cows, temperature was measured rectally. In both experiments, body temperature increased significantly after vaccination (1.0 ± 0.9°C and 0.7 ± 0.8°C). A significant difference was also found in body temperature between vaccinated and control cows. Thirty percent of the vaccinated animals in experiment 1 showed reversible swelling at the injection site as a reaction to the vaccination. The results indicate that vaccination against Q fever causes a transient increase of body temperature that peaks in the first 12 to 24h and declines after that. In experiment 2, vaccinated cows (26.8 ± 0.39 kg/d) produced significantly less milk than did control cows (28.2 ± 0.44 kg

  13. Analysis of the cbhE' plasmid gene from acute disease-causing isolates of Coxiella burnetii.

    PubMed

    Minnick, M F; Small, C L; Frazier, M E; Mallavia, L P

    1991-07-15

    A gene termed cbhE' was cloned from the QpH1 plasmid of Coxiella burnetii. Expression of recombinants containing cbhE' in vitro and in Escherichia coli maxicells, produced an insert-encoded polypeptide of approx. 42 kDa. The CbhE protein was not cleaved when intact maxicells were treated with trypsin. Hybridizations of total DNA isolated from the six strains of C. burnetii indicate that this gene is unique to C. burnetii strains associated with acute disease, i.e., Hamilton[I], Vacca[II], and Rasche[III]. The cbhE' gene was not detected in strains associated with chronic disease (Biotzere[IV] and Corazon[V]) or the Dod[VI] strain. The cbhE' open reading frame (ORF) is 1022 bp in length and is preceded by a predicted promoter/Shine-Dalgarno (SD) region of TCAACT(-35)-N16-TAAAAT(-10)-N14-AGAAGGA (SD) located 10 nucleotides (nt) before the presumed AUG start codon. The ORF ends with a single UAA stop codon and has no apparent Rho-factor-independent terminator following it. The cbhE' gene codes for the CbhE protein of 341 amino acid (aa) residues with a deduced Mr of 39,442. CbhE is predominantly hydrophilic with a predicted pI of 4.43. The function of CbhE is unknown. No nt or aa sequences with homology to cbhE' or CbhE, respectively, were found in searches of a number of data bases.

  14. A probably minor role for land-applied goat manure in the transmission of Coxiella burnetii to humans in the 2007-2010 Dutch Q fever outbreak.

    PubMed

    van den Brom, René; Roest, Hendrik-Jan; de Bruin, Arnout; Dercksen, Daan; Santman-Berends, Inge; van der Hoek, Wim; Dinkla, Annemiek; Vellema, Jelmer; Vellema, Piet

    2015-01-01

    In 2007, Q fever started to become a major public health problem in the Netherlands, with small ruminants as most probable source. In order to reduce environmental contamination, control measures for manure were implemented because of the assumption that manure was highly contaminated with Coxiella burnetii. The aims of this study were 1) to clarify the role of C. burnetii contaminated manure from dairy goat farms in the transmission of C. burnetii to humans, 2) to assess the impact of manure storage on temperature profiles in dunghills, and 3) to calculate the decimal reduction time of the Nine Mile RSA 493 reference strain of C. burnetii under experimental conditions in different matrices. For these purposes, records on distribution of manure from case and control herds were mapped and a potential relation to incidences of human Q fever was investigated. Additionally, temperatures in two dunghills were measured and related to heat resistance of C. burnetii. Results of negative binomial regression showed no significant association between the incidence of human Q fever cases and the source of manure. Temperature measurements in the core and shell of dunghills on two farms were above 40°C for at least ten consecutive days which would result in a strong reduction of C. burnetii over time. Our findings indicate that there is no relationship between incidence of human Q fever and land applied manure from dairy goat farms with an abortion wave caused by C. burnetii. Temperature measurements in dunghills on two farms with C. burnetii shedding dairy goat herds further support the very limited role of goat manure as a transmission route during the Dutch human Q fever outbreak. It is very likely that the composting process within a dunghill will result in a clear reduction in the number of viable C. burnetii. PMID:25816149

  15. A Probably Minor Role for Land-Applied Goat Manure in the Transmission of Coxiella burnetii to Humans in the 2007–2010 Dutch Q Fever Outbreak

    PubMed Central

    van den Brom, René; Roest, Hendrik-Jan; de Bruin, Arnout; Dercksen, Daan; Santman-Berends, Inge; van der Hoek, Wim; Dinkla, Annemiek; Vellema, Jelmer; Vellema, Piet

    2015-01-01

    In 2007, Q fever started to become a major public health problem in the Netherlands, with small ruminants as most probable source. In order to reduce environmental contamination, control measures for manure were implemented because of the assumption that manure was highly contaminated with Coxiella burnetii. The aims of this study were 1) to clarify the role of C. burnetii contaminated manure from dairy goat farms in the transmission of C. burnetii to humans, 2) to assess the impact of manure storage on temperature profiles in dunghills, and 3) to calculate the decimal reduction time of the Nine Mile RSA 493 reference strain of C. burnetii under experimental conditions in different matrices. For these purposes, records on distribution of manure from case and control herds were mapped and a potential relation to incidences of human Q fever was investigated. Additionally, temperatures in two dunghills were measured and related to heat resistance of C. burnetii. Results of negative binomial regression showed no significant association between the incidence of human Q fever cases and the source of manure. Temperature measurements in the core and shell of dunghills on two farms were above 40°C for at least ten consecutive days which would result in a strong reduction of C. burnetii over time. Our findings indicate that there is no relationship between incidence of human Q fever and land applied manure from dairy goat farms with an abortion wave caused by C. burnetii. Temperature measurements in dunghills on two farms with C. burnetii shedding dairy goat herds further support the very limited role of goat manure as a transmission route during the Dutch human Q fever outbreak. It is very likely that the composting process within a dunghill will result in a clear reduction in the number of viable C. burnetii. PMID:25816149

  16. Coxiella burnetii Seroprevalence and Risk Factors in Cattle Farmers and Farm Residents in Three Northeastern Provinces and Inner Mongolia Autonomous Region, China.

    PubMed

    Sun, Wu-Wen; Cong, Wei; Li, Mao-Hui; Wang, Chun-Feng; Shan, Xiao-Feng; Qian, Ai-Dong

    2016-01-01

    Little is known about Coxiella burnetii infection among cattle farmers and farm residents in China. Thus, the present study was conducted to detect the seroprevalence of C. burnetii infection and estimate associated risk factors among cattle farmers and farm residents in China. A cross-sectional study was designed, and sera of 362 people living or working on 106 cattle farms were tested for C. burnetii IgG and IgM antibodies by immunofluorescence assay. Overall C. burnetii seroprevalence was 35.6% (129/362, 95% CI: 30.70-40.57), and 112 participants had experienced a past infection and seventeen (4.7%) had experienced a relatively recent infection. In the final combined multilevel model, the following activities were significantly associated with presence of antibodies against C. burnetii: milking cattle, providing general healthcare to cattle, providing birth assistance, contact dead-born animals, urbanization, and presence of mice and/or rats in the stable. Moreover, presence of disinfection equipment was a significant protective factor. This is the first study addressing the seroprevalence and risk factors of C. burnetii infection in cattle farmers and farm residents in three northeastern provinces and Inner Mongolia Autonomous Region, China. PMID:26966688

  17. Coxiella burnetii Seroprevalence and Risk Factors in Cattle Farmers and Farm Residents in Three Northeastern Provinces and Inner Mongolia Autonomous Region, China

    PubMed Central

    Sun, Wu-Wen; Cong, Wei; Li, Mao-Hui; Wang, Chun-Feng; Shan, Xiao-Feng; Qian, Ai-Dong

    2016-01-01

    Little is known about Coxiella burnetii infection among cattle farmers and farm residents in China. Thus, the present study was conducted to detect the seroprevalence of C. burnetii infection and estimate associated risk factors among cattle farmers and farm residents in China. A cross-sectional study was designed, and sera of 362 people living or working on 106 cattle farms were tested for C. burnetii IgG and IgM antibodies by immunofluorescence assay. Overall C. burnetii seroprevalence was 35.6% (129/362, 95% CI: 30.70–40.57), and 112 participants had experienced a past infection and seventeen (4.7%) had experienced a relatively recent infection. In the final combined multilevel model, the following activities were significantly associated with presence of antibodies against C. burnetii: milking cattle, providing general healthcare to cattle, providing birth assistance, contact dead-born animals, urbanization, and presence of mice and/or rats in the stable. Moreover, presence of disinfection equipment was a significant protective factor. This is the first study addressing the seroprevalence and risk factors of C. burnetii infection in cattle farmers and farm residents in three northeastern provinces and Inner Mongolia Autonomous Region, China. PMID:26966688

  18. Generation and Multi-phenotypic High-content Screening of Coxiella burnetii Transposon Mutants

    PubMed Central

    Martinez, Eric; Cantet, Franck; Bonazzi, Matteo

    2015-01-01

    Invasion and colonization of host cells by bacterial pathogens depend on the activity of a large number of prokaryotic proteins, defined as virulence factors, which can subvert and manipulate key host functions. The study of host/pathogen interactions is therefore extremely important to understand bacterial infections and develop alternative strategies to counter infectious diseases. This approach however, requires the development of new high-throughput assays for the unbiased, automated identification and characterization of bacterial virulence determinants. Here, we describe a method for the generation of a GFP-tagged mutant library by transposon mutagenesis and the development of high-content screening approaches for the simultaneous identification of multiple transposon-associated phenotypes. Our working model is the intracellular bacterial pathogen Coxiellaburnetii, the etiological agent of the zoonosis Q fever, which is associated with severe outbreaks with a consequent health and economic burden. The obligate intracellular nature of this pathogen has, until recently, severely hampered the identification of bacterial factors involved in host pathogen interactions, making of Coxiella the ideal model for the implementation of high-throughput/high-content approaches. PMID:25992686

  19. Serological survey of antibodies to Toxoplasma gondii and Coxiella burnetii in rodents in north-western African islands (Canary Islands and Cape Verde).

    PubMed

    Foronda, Pilar; Plata-Luis, Josué; del Castillo-Figueruelo, Borja; Fernández-Álvarez, Ángela; Martín-Alonso, Aarón; Feliu, Carlos; Cabral, Marilena D; Valladares, Basilio

    2015-01-01

    Coxiella burnetii and Toxoplasma gondii are intracellular parasites that cause important reproductive disorders in animals and humans worldwide, resulting in high economic losses. The aim of the present study was to analyse the possible role of peridomestic small mammals in the maintenance and transmission of C. burnetii and T. gondii in the north-western African archipelagos of the Canary Islands and Cape Verde, where these species are commonly found affecting humans and farm animals. Between 2009 and 2013, 108 black rats (Rattus rattus) and 77 mice (Mus musculus) were analysed for the presence of Coxiella and Toxoplasma antibodies by enzyme-linked immunosorbent assay (ELISA) and indirect immunofluorescence (IFA), respectively. Our results showed a wide distribution of C. burnetii and T. gondii, except for T. gondii in Cape Verde, in both rodent species. The overall seroprevalence of C. burnetii antibodies was 12.4%; 21.1% for Cape Verde and 10.2% for the Canary Islands. With respect to T. gondii, seropositive rodents were only observed in the Canary Islands, with an overall seroprevalence of 15%. Considering the fact that both pathogens can infect a large range of hosts, including livestock and humans, the results are of public health and veterinary importance and could be used by governmental entities to manage risk factors and to prevent future cases of Q fever and toxoplasmosis. PMID:26244685

  20. Studying Coxiella burnetii Type IV Substrates in the Yeast Saccharomyces cerevisiae: Focus on Subcellular Localization and Protein Aggregation.

    PubMed

    Rodríguez-Escudero, María; Cid, Víctor J; Molina, María; Schulze-Luehrmann, Jan; Lührmann, Anja; Rodríguez-Escudero, Isabel

    2016-01-01

    Coxiella burnetii is a Gram-negative obligate parasitic bacterium that causes the disease Q-fever in humans. To establish its intracellular niche, it utilizes the Icm/Dot type IVB secretion system (T4BSS) to inject protein effectors into the host cell cytoplasm. The host targets of most cognate and candidate T4BSS-translocated effectors remain obscure. We used the yeast Saccharomyces cerevisiae as a model to express and study six C. burnetii effectors, namely AnkA, AnkB, AnkF, CBU0077, CaeA and CaeB, in search for clues about their role in C. burnetii virulence. When ectopically expressed in HeLa cells, these effectors displayed distinct subcellular localizations. Accordingly, GFP fusions of these proteins produced in yeast also decorated distinct compartments, and most of them altered cell growth. CaeA was ubiquitinated both in yeast and mammalian cells and, in S. cerevisiae, accumulated at juxtanuclear quality-control compartments (JUNQs) and insoluble protein deposits (IPODs), characteristic of aggregative or misfolded proteins. AnkA, which was not ubiquitinated, accumulated exclusively at the IPOD. CaeA, but not AnkA or the other effectors, caused oxidative damage in yeast. We discuss that CaeA and AnkA behavior in yeast may rather reflect misfolding than recognition of conserved targets in the heterologous system. In contrast, CBU0077 accumulated at vacuolar membranes and abnormal ER extensions, suggesting that it interferes with vesicular traffic, whereas AnkB associated with the yeast nucleolus. Both effectors shared common localization features in HeLa and yeast cells. Our results support the idea that C. burnetii T4BSS effectors manipulate multiple host cell targets, which can be conserved in higher and lower eukaryotic cells. However, the behavior of CaeA and AnkA prompt us to conclude that heterologous protein aggregation and proteostatic stress can be a limitation to be considered when using the yeast model to assess the function of bacterial effectors.

  1. Studying Coxiella burnetii Type IV Substrates in the Yeast Saccharomyces cerevisiae: Focus on Subcellular Localization and Protein Aggregation

    PubMed Central

    Rodríguez-Escudero, María; Cid, Víctor J.; Molina, María; Schulze-Luehrmann, Jan; Lührmann, Anja; Rodríguez-Escudero, Isabel

    2016-01-01

    Coxiella burnetii is a Gram-negative obligate parasitic bacterium that causes the disease Q-fever in humans. To establish its intracellular niche, it utilizes the Icm/Dot type IVB secretion system (T4BSS) to inject protein effectors into the host cell cytoplasm. The host targets of most cognate and candidate T4BSS-translocated effectors remain obscure. We used the yeast Saccharomyces cerevisiae as a model to express and study six C. burnetii effectors, namely AnkA, AnkB, AnkF, CBU0077, CaeA and CaeB, in search for clues about their role in C. burnetii virulence. When ectopically expressed in HeLa cells, these effectors displayed distinct subcellular localizations. Accordingly, GFP fusions of these proteins produced in yeast also decorated distinct compartments, and most of them altered cell growth. CaeA was ubiquitinated both in yeast and mammalian cells and, in S. cerevisiae, accumulated at juxtanuclear quality-control compartments (JUNQs) and insoluble protein deposits (IPODs), characteristic of aggregative or misfolded proteins. AnkA, which was not ubiquitinated, accumulated exclusively at the IPOD. CaeA, but not AnkA or the other effectors, caused oxidative damage in yeast. We discuss that CaeA and AnkA behavior in yeast may rather reflect misfolding than recognition of conserved targets in the heterologous system. In contrast, CBU0077 accumulated at vacuolar membranes and abnormal ER extensions, suggesting that it interferes with vesicular traffic, whereas AnkB associated with the yeast nucleolus. Both effectors shared common localization features in HeLa and yeast cells. Our results support the idea that C. burnetii T4BSS effectors manipulate multiple host cell targets, which can be conserved in higher and lower eukaryotic cells. However, the behavior of CaeA and AnkA prompt us to conclude that heterologous protein aggregation and proteostatic stress can be a limitation to be considered when using the yeast model to assess the function of bacterial effectors

  2. The Sero-epidemiology of Coxiella burnetii in Humans and Cattle, Western Kenya: Evidence from a Cross-Sectional Study

    PubMed Central

    Thomas, Lian F.; Cook, Elizabeth A. J.; de Glanville, William A.; Atkinson, Peter M.; Wamae, Claire N.; Fèvre, Eric M.

    2016-01-01

    Evidence suggests that the intracellular bacterial pathogen Coxiella burnetii (which causes Q fever) is widespread, with a near global distribution. While there has been increasing attention to Q fever epidemiology in high-income settings, a recent systematic review highlighted significant gaps in our understanding of the prevalence, spatial distribution and risk factors for Q fever infection across Africa. This research aimed to provide a One Health assessment of Q fever epidemiology in parts of Western and Nyanza Provinces, Western Kenya, in cattle and humans. A cross-sectional survey was conducted: serum samples from 2049 humans and 955 cattle in 416 homesteads were analysed for C. burnetii antibodies. Questionnaires covering demographic, socio-economic and husbandry information were also administered. These data were linked to environmental datasets based on geographical locations (e.g., land cover). Correlation and spatial-cross correlation analyses were applied to assess the potential link between cattle and human seroprevalence. Multilevel regression analysis was used to assess the relationships between a range of socio-economic, demographic and environmental factors and sero-positivity in both humans and animals. The overall sero-prevalence of C. burnetii was 2.5% in humans and 10.5% in cattle, but we found no evidence of correlation between cattle and human seroprevalence either within households, or when incorporating spatial proximity to other households in the survey. Multilevel modelling indicated the importance of several factors for exposure to the organism. Cattle obtained from market (as opposed to those bred in their homestead) and those residing in areas with lower precipitation levels had the highest sero-prevalence. For humans, the youngest age group had the highest odds of seropositivity, variations were observed between ethnic groups, and frequent livestock contact (specifically grazing and dealing with abortion material) was also a risk

  3. Transcriptional Profiling of Coxiella burnetii Reveals Extensive Cell Wall Remodeling in the Small Cell Variant Developmental Form

    PubMed Central

    Sandoz, Kelsi M.; Popham, David L.; Beare, Paul A.; Sturdevant, Daniel E.; Hansen, Bryan; Nair, Vinod; Heinzen, Robert A.

    2016-01-01

    A hallmark of Coxiella burnetii, the bacterial cause of human Q fever, is a biphasic developmental cycle that generates biologically, ultrastructurally, and compositionally distinct large cell variant (LCV) and small cell variant (SCV) forms. LCVs are replicating, exponential phase forms while SCVs are non-replicating, stationary phase forms. The SCV has several properties, such as a condensed nucleoid and an unusual cell envelope, suspected of conferring enhanced environmental stability. To identify genetic determinants of the LCV to SCV transition, we profiled the C. burnetii transcriptome at 3 (early LCV), 5 (late LCV), 7 (intermediate forms), 14 (early SCV), and 21 days (late SCV) post-infection of Vero epithelial cells. Relative to early LCV, genes downregulated in the SCV were primarily involved in intermediary metabolism. Upregulated SCV genes included those involved in oxidative stress responses, arginine acquisition, and cell wall remodeling. A striking transcriptional signature of the SCV was induction (>7-fold) of five genes encoding predicted L,D transpeptidases that catalyze nonclassical 3–3 peptide cross-links in peptidoglycan (PG), a modification that can influence several biological traits in bacteria. Accordingly, of cross-links identified, muropeptide analysis showed PG of SCV with 46% 3–3 cross-links as opposed to 16% 3–3 cross-links for LCV. Moreover, electron microscopy revealed SCV with an unusually dense cell wall/outer membrane complex as compared to LCV with its clearly distinguishable periplasm and inner and outer membranes. Collectively, these results indicate the SCV produces a unique transcriptome with a major component directed towards remodeling a PG layer that likely contributes to Coxiella’s environmental resistance. PMID:26909555

  4. Essential Role for the Response Regulator PmrA in Coxiella burnetii Type 4B Secretion and Colonization of Mammalian Host Cells

    PubMed Central

    Beare, Paul A.; Sandoz, Kelsi M.; Larson, Charles L.; Howe, Dale; Kronmiller, Brent

    2014-01-01

    Successful host cell colonization by the Q fever pathogen, Coxiella burnetii, requires translocation of effector proteins into the host cytosol by a Dot/Icm type 4B secretion system (T4BSS). In Legionella pneumophila, the two-component system (TCS) PmrAB regulates the Dot/Icm T4BSS and several additional physiological processes associated with pathogenesis. Because PmrA consensus regulatory elements are associated with some dot/icm and substrate genes, a similar role for PmrA in regulation of the C. burnetii T4BSS has been proposed. Here, we constructed a C. burnetii pmrA deletion mutant to directly probe PmrA-mediated gene regulation. Compared to wild-type bacteria, C. burnetii ΔpmrA exhibited severe intracellular growth defects that coincided with failed secretion of effector proteins. Luciferase gene reporter assays demonstrated PmrA-dependent expression of 5 of 7 dot/icm operons and 9 of 11 effector-encoding genes with a predicted upstream PmrA regulatory element. Mutational analysis verified consensus sequence nucleotides required for PmrA-directed transcription. RNA sequencing and whole bacterial cell mass spectrometry of wild-type C. burnetii and the ΔpmrA mutant uncovered new components of the PmrA regulon, including several genes lacking PmrA motifs that encoded Dot/Icm substrates. Collectively, our results indicate that the PmrAB TCS is a critical virulence factor that regulates C. burnetii Dot/Icm secretion. The presence of PmrA-responsive genes lacking PmrA regulatory elements also suggests that the PmrAB TCS controls expression of regulatory systems associated with the production of additional C. burnetii proteins involved in host cell parasitism. PMID:24610709

  5. Treatment and Prophylactic Strategy for Coxiella burnetii Infection of Aneurysms and Vascular Grafts: A Retrospective Cohort Study.

    PubMed

    Eldin, Carole; Mailhe, Morgane; Lions, Caroline; Carrieri, Patrizia; Safi, Hazem; Brouqui, Philippe; Raoult, Didier

    2016-03-01

    Coxiella burnetii vascular infections continue to be very severe diseases and no guidelines exist about their prevention. In terms of treatment, the benefit of the surgical removal of infected tissues has been suggested by 1 retrospective study.We present a case of a C burnetii abdominal aortic graft infection for which we observed a dramatic clinical and biological recovery after surgery. We thus performed a retrospective cohort study to evaluate the impact of surgery on survival and serological outcome for patients with Q fever vascular infections diagnosed in our center.Between 1986 and February 2015, 100 patients were diagnosed with Q fever vascular infections. The incidence of these infections has significantly increased over the past 5 years, in comparison with the mean annual incidence over the preceding 22 years (8.83 cases per year versus 3.14 cases per year, P = 0.001). A two-and-a-half-year follow-up was available for 66 patients, of whom 18.2% died. We observed 6.5% of deaths in the group of patients who were operated upon at 2 and a half years, in comparison with 28.6% in the group which were not operated upon (P = 0.02). Surgery was the only factor that had a positive impact on survival at 2 and a half years using univariate analysis [hazard ratio: 0.17 [95% CI]: [0.039-0.79]; P = 0.024]. Surgery was also associated with a good serological outcome (74.1% vs 57.1% of patients, P = 0.03). In the group of patients with vascular graft infections (n = 47), surgery had a positive impact on serological outcome at 2 and a half years (85.7% vs 42.9%, P < 0.001) [hazard ratio: 0.40 [95% CI]: [0.17-098]; P = 0.046] and tended to be associated with lower although not statistically significant mortality (11.1% vs 27.6% of deaths, P = 0.19).Surgical treatment confers a benefit in terms of survival following C burnetii vascular infections. However, given the high mortality of these infections and their rising incidence, we propose a

  6. Pore-forming activity of Coxiella burnetii outer membrane protein oligomer comprised of 29.5- and 31-kDa polypeptides. Inhibition of porin activity by monoclonal antibodies 4E8 and 4D6.

    PubMed

    Banerjee-Bhatnagar, N; Bolt, C R; Williams, J C

    1996-07-23

    Envelopes of large-cell variant Coxiella burnetii, the agent of Q fever, were the starting material for purification of an outer membrane protein (OMP) oligomer with aggregate molecular mass of approximately 2 x 10(4) kDa. The oligomer was resistant to trypsin and dissociation by SDS at 100 degrees C. Reducing agents dissociated the oligomer into monomers of 29.5 and 31 kDa, which migrated as a doublet during SDS-polyacrylamide gel electrophoresis. Both monomers were reactive in an immunoblot assay with monoclonal antibodies (mAbs) 4E8 and 4D6, which were previously selected for their reactivity with purified and SDS-denatured 29.5 kDa protein. Proteoliposomes were functional in an equilibrium assay at pH 7 and a swelling assay at pH 7 and 4.5. The pores in proteoliposomes allowed the passage of arabinose, glucose, and sucrose, but restricted stachyose. Polyclonal antibodies to C. burnetii cells and the mAbs were able to bind C. burnetii at pH 7 and 4.5. The uptake of 14C-glucose at pH 4.5 was inhibited by polyclonal antibodies and mAbs after binding to cells at pH 7. The mAbs did not inhibit 14C-glucose uptake at pH 4.5 after binding to cells at pH 4.5. Although the mAbs bind C. burnetii porin epitopes before and after acid activation, the mAbs bound under acidic conditions were unable to inhibit porin function. The inhibition of porin channel function by mAbs confirms the role of porin as a permeability barrier for the subsequent active transport of glucose by C. burnetii. In another study, we showed that the 29.5 kDa OMP antigen induced active immunity against virulent challenge. This information, combined with the recent confirmation that porins are important antigens in the induction of specific protective immune responses against infection by gram-negative bacteria, suggests that humoral immunity directed against C. burnetii porins might play an important role in immunity against Q fever (human infection) and coxiellosis (animal infection), global enzootic

  7. Massive Infection of Seabird Ticks with Bacterial Species Related to Coxiella burnetii

    PubMed Central

    Dietrich, Muriel; Lebarbenchon, Camille; Jaeger, Audrey; Le Rouzic, Céline; Bastien, Matthieu; Lagadec, Erwan; McCoy, Karen D.; Pascalis, Hervé; Le Corre, Matthieu; Dellagi, Koussay; Tortosa, Pablo

    2014-01-01

    Seabird ticks are known reservoirs of bacterial pathogens of medical importance; however, ticks parasitizing tropical seabirds have received less attention than their counterparts from temperate and subpolar regions. Recently, Rickettsia africae was described to infect seabird ticks of the western Indian Ocean and New Caledonia, constituting the only available data on bacterial pathogens associated with tropical seabird tick species. Here, we combined a pyrosequencing-based approach with a classical molecular analysis targeting bacteria of potential medical importance in order to describe the bacterial community in two tropical seabird ticks, Amblyomma loculosum and Carios (Ornithodoros) capensis. We also investigated the patterns of prevalence and host specificity within the biogeographical context of the western Indian Ocean islands. The bacterial community of the two tick species was characterized by a strong dominance of Coxiella and Rickettsia. Our data support a strict Coxiella-host tick specificity, a pattern resembling the one found for Rickettsia spp. in the same two seabird tick species. Both the high prevalence and stringent host tick specificity suggest that these bacteria may be tick symbionts with probable vertical transmission. Detailed studies of the pathogenicity of these bacteria will now be required to determine whether horizontal transmission can occur and to clarify their status as potential human pathogens. More generally, our results show that the combination of next generation sequencing with targeted detection/genotyping approaches proves to be efficient in poorly investigated fields where research can be considered to be starting from scratch. PMID:24657860

  8. Massive infection of seabird ticks with bacterial species related to Coxiella burnetii.

    PubMed

    Wilkinson, David A; Dietrich, Muriel; Lebarbenchon, Camille; Jaeger, Audrey; Le Rouzic, Céline; Bastien, Matthieu; Lagadec, Erwan; McCoy, Karen D; Pascalis, Hervé; Le Corre, Matthieu; Dellagi, Koussay; Tortosa, Pablo

    2014-06-01

    Seabird ticks are known reservoirs of bacterial pathogens of medical importance; however, ticks parasitizing tropical seabirds have received less attention than their counterparts from temperate and subpolar regions. Recently, Rickettsia africae was described to infect seabird ticks of the western Indian Ocean and New Caledonia, constituting the only available data on bacterial pathogens associated with tropical seabird tick species. Here, we combined a pyrosequencing-based approach with a classical molecular analysis targeting bacteria of potential medical importance in order to describe the bacterial community in two tropical seabird ticks, Amblyomma loculosum and Carios (Ornithodoros) capensis. We also investigated the patterns of prevalence and host specificity within the biogeographical context of the western Indian Ocean islands. The bacterial community of the two tick species was characterized by a strong dominance of Coxiella and Rickettsia. Our data support a strict Coxiella-host tick specificity, a pattern resembling the one found for Rickettsia spp. in the same two seabird tick species. Both the high prevalence and stringent host tick specificity suggest that these bacteria may be tick symbionts with probable vertical transmission. Detailed studies of the pathogenicity of these bacteria will now be required to determine whether horizontal transmission can occur and to clarify their status as potential human pathogens. More generally, our results show that the combination of next generation sequencing with targeted detection/genotyping approaches proves to be efficient in poorly investigated fields where research can be considered to be starting from scratch.

  9. The attenuated nine mile phase II clone 4/RSA439 strain of Coxiella burnetii is highly virulent for severe combined immunodeficient (SCID) mice.

    PubMed

    Islam, Aminul; Lockhart, Michelle; Stenos, John; Graves, Stephen

    2013-10-01

    The Nine Mile phase II clone 4 (NMIIC4) strain of Coxiella burnetii is an attenuated phase II strain that has lost the genes for virulence determinant type 1 lipopolysaccharide. These bacteria were very virulent for severe combined immunodeficient (SCID) mice. The lethal dose 50 (LD50) was ~10 bacteria. Infected SCID mice died between Day 28 and Day 53 post-infection. At termination of the experiment (Day 60) only 5 of 24 mice had survived. The degree of splenomegaly was directly related to the bacterial load in the SCID mice spleens. The NMIIC4 was avirulent in immunocompetent wild mice and bacterial DNA copies in splenic tissue were extremely low. The SCID mice that were inoculated with high doses of heat inactivated NMIIC4 C. burnetii were all alive at Day 60 and without splenomegaly. It appears that the phase I lipopolysaccharide present in virulent Nine Mile phase I but not in attenuated NMIIC4 is not the only virulence factor for C. burnetii.

  10. Simultaneous detection of Chlamydia spp., Coxiella burnetii, and Neospora caninum in abortion material of ruminants by multiplex real-time polymerase chain reaction.

    PubMed

    Reisberg, Kerstin; Selim, Abdelfattah M; Gaede, Wolfgang

    2013-09-01

    Chlamydia spp., Coxiella burnetii, and Neospora caninum are responsible for reproductive diseases and are closely linked with high abortion rates in ruminants. Furthermore, C. burnetii and Chlamydia spp. have zoonotic potential. A real-time polymerase chain reaction (PCR) assay was developed for the simultaneous detection of Chlamydia spp., C. burnetii, and N. caninum. The detection of beta-actin as internal control in the same PCR reaction provides additional information about sample quality by detecting the presence of PCR inhibitors. The multiplex real-time PCR developed in the current study shows a greater sensitivity compared to previously used single-target PCR reactions with a reproducible detection limit of 0.13 plasmid copies per PCR for each target. Additional parallel amplification of all detectable pathogens did not adversely impact sensitivity. This new multiplex PCR allows the highly sensitive, cost-effective, and rapid detection of 3 important pathogens and has the potential to be a useful time-saving tool in the routine diagnosis of abortion cases in ruminants.

  11. 18F-FDG PET/CT as a central tool in the shift from chronic Q fever to Coxiella burnetii persistent focalized infection: A consecutive case series.

    PubMed

    Eldin, Carole; Melenotte, Cléa; Million, Matthieu; Cammilleri, Serge; Sotto, Albert; Elsendoorn, Antoine; Thuny, Franck; Lepidi, Hubert; Roblot, France; Weitten, Thierry; Assaad, Souad; Bouaziz, Anissa; Chapuzet, Claire; Gras, Guillaume; Labussiere, Anne-Sophie; Landais, Cécile; Longuet, Pascale; Masseau, Agathe; Mundler, Olivier; Raoult, Didier

    2016-08-01

    Because Q fever is mostly diagnosed serologically, localizing a persistent focus of Coxiella burnetii infection can be challenging. F-fluorodeoxyglucose positron emission tomography/computed tomography (F-FDG PET/CT) could be an interesting tool in this context.We performed a retrospective study on patients diagnosed with C burnetii infection, who had undergone F-FDG PET/CT between 2009 and 2015. When positive F-FDG PET/CT results were obtained, we tried to determine if it changed the previous diagnosis by discovering or confirming a suspected focus of C burnetii infection.One hundred sixty-seven patients benefited from F-FDG PET/CT. The most frequent clinical subgroup before F-FDG PET/CT was patients with no identified focus of infection, despite high IgG1 serological titers (34%). For 59% (n = 99) of patients, a hypermetabolic focus was identified. For 62 patients (62.6%), the positive F-FDG PET/CT allowed the diagnosis to be changed. For 24 of them, (38.7%), a previously unsuspected focus of infection was discovered. Forty-two (42%) positive patients had more than 1 hypermetabolic focus. We observed 21 valvular foci, 34 vascular foci, and a high proportion of osteoarticular localizations (n = 21). We also observed lymphadenitis (n = 27), bone marrow hypermetabolism (n = 11), and 9 pulmonary localizations.We confirmed thatF-FDG PET/CT is a central tool in the diagnosis of C burnetii focalized persistent infection. We proposed new diagnostic scores for 2 main clinical entities identified using F-FDG PET/CT: osteoarticular persistent infections and lymphadenitis. PMID:27559944

  12. Isolation of Coxiella burnetii by a centrifugation shell-vial assay from ticks collected in Cyprus: detection by nested polymerase chain reaction (PCR) and by PCR-restriction fragment length polymorphism analyses.

    PubMed

    Spyridaki, Ioanna; Psaroulaki, Anna; Loukaides, Fidias; Antoniou, Maria; Hadjichristodolou, Christos; Tselentis, Yannis

    2002-01-01

    Ticks are the principal vectors and reservoirs of Coxiella burnetii. The identification of isolates is necessary for understanding the clinical diversity of Q fever in different geographic areas. This is the first report of isolation of C. burnetii from ticks by the shell-vial assay and by nested polymerase chain reaction (PCR) assay for the detection of this pathogen in ticks. Of 141 ticks collected in Cyprus (Rhipicephalus sanguineus and Hyalloma spp.), 10% were found to be infected with C. burnetii. Three ticks were positive by hemolymph test, and 11 triturated ticks were positive by nested PCR. Three isolates were obtained by the centrifugation shell-vial technique. Analysis by PCR, then restriction fragment length polymorphism showed that the 3 Cyprus isolates had identical restriction profiles to reference strains Nine Mile and Q212. The methods described are useful in studying the epidemiology and ecology of C. burnetii. PMID:12135275

  13. Bulk tank milk surveillance as a measure to detect Coxiella burnetii shedding dairy goat herds in the Netherlands between 2009 and 2014.

    PubMed

    Van den Brom, R; Santman-Berends, I; Luttikholt, S; Moll, L; Van Engelen, E; Vellema, P

    2015-06-01

    In the period from 2005 to 2009, Coxiella burnetii was a cause of abortion waves at 28 dairy goat farms and 2 dairy sheep farms in the Netherlands. Two years after the first abortion waves, a large human Q fever outbreak started mainly in the same region, and aborting small ruminants were regarded as most probable source. To distinguish between infected and noninfected herds, a surveillance program started in October 2009, based on PCR testing of bulk tank milk (BTM) samples, which had never been described before. The aim of this study was to analyze the effectiveness of this surveillance program and to evaluate both the effect of culling of pregnant dairy goats on positive farms and of vaccination on BTM results. Bulk tank milk samples were tested for C. burnetii DNA using a real-time PCR, and results were analyzed in relation to vaccination, culling, and notifiable (officially reported to government) C. burnetii abortion records. In spring and autumn, BTM samples were also tested for antibodies using an ELISA, and results were evaluated in relation to the compulsory vaccination campaign. Between October 2009 and April 2014, 1,660 (5.6%) out of 29,875 BTM samples from 401 dairy goat farms tested positive for C. burnetii DNA. The percentage of positive samples dropped from 20.5% in 2009 to 0.3% in 2014. In a multivariable model, significantly higher odds of being PCR positive in the BTM surveillance program were found in farms of which all pregnant dairy goats were culled. Additionally, the risk for C. burnetii BTM PCR positivity significantly decreased after multiple vaccinations. Bulk tank milk ELISA results were significantly higher after vaccination than before. The ELISA results were higher after multiple vaccinations compared with a single vaccination, and ELISA results on officially declared infected farms were significantly higher compared with noninfected farms. In conclusion, BTM surveillance is an effective and useful tool to detect C. burnetii shedding

  14. Brucellosis and Coxiella burnetii Infection in Householders and Their Animals in Secure Villages in Herat Province, Afghanistan: A Cross-Sectional Study

    PubMed Central

    Akbarian, Zarif; Ziay, Ghulam; Schauwers, Willy; Noormal, Bashir; Saeed, Islam; Qanee, Abul Hussain; Shahab, Zabiullah; Dennison, Tania; Dohoo, Ian; Jackson, Ronald

    2015-01-01

    Background Brucellosis and coxiellosis are known to be endemic in ruminant populations throughout Afghanistan, but information about their prevalence and factors that affect prevalence in householders and livestock under diverse husbandry systems and pastoral settings is sparse. Methods/Principal Findings We conducted a cross-sectional survey to investigate the seroprevalence of brucellosis and Coxiella burnetii in humans and livestock in six secure districts in Herat from 26th December 2012–17th January 2013. A total of 204 households with livestock were surveyed in six Kuchi and five sedentary type villages. Blood samples from 1,017 humans, 1,143 sheep, 876 goats and 344 cattle were tested for brucellosis and Q fever. About one in six households (15.7%) had at least one Brucella seropositive person, about one in eight households (12.3%) had at least one Brucella seropositive animal and about one in four (24.5%) had either seropositive animals or humans. Ninety-seven percent of households had at least one C. burnetii seropositive person and 98.5% of households had one or more C. burnetii seropositive animals. Forty- seven householders had serological evidence of exposure to both C. burnetii and Brucella and eight animals were serologically positive for both diseases. Drinking unpasteurised milk (OR 1.6), treating animals for ticks (OR 1.4), milking sheep (OR 1.4), male gender (OR 1.4) and seropositivity to Brucella (OR 4.3) were identified as risk factors for seropositivity to C. burnetii in householders. Household factors associated with households having either Brucella seropositive animals or humans were Kuchi households (OR 2.5), having ≤4 rooms in the house (OR 2.9) and not owning land (OR 2.9). Conclusions The results from this study provide baseline information for the planning and monitoring of future interventions against these diseases. The implementation of this study greatly improved collaboration, coordination and capability of veterinary and

  15. Serological survey using ELISA to determine the prevalence of Coxiella burnetii infection (Q fever) in sheep and goats in Great Britain.

    PubMed

    Lambton, S L; Smith, R P; Gillard, K; Horigan, M; Farren, C; Pritchard, G C

    2016-01-01

    A survey of Coxiella burnetii infection (Q fever) in sheep flocks and goat herds in Great Britain was undertaken. A total of 5791 sheep (384 flocks) and 522 goats (145 herds) were examined for C. burnetii antibodies using an ELISA. Overall, 53 sheep (37 flocks), and four goats (four herds), tested positive. Estimates of individual animal, between-flock/-herd and within-flock/-herd crude prevalences were 0·9%, 10·2% and 9·0%, respectively, for sheep, and 0·8%, 3% and 26·3%, respectively, for goats. With sheep, the likelihood of an animal testing positive increased with total flock size (P = 0·002) and number of breeding ewes in the flock (P = 0·021). It also increased with number of goats within a 10 km radius (P = 0·038). There was no evidence for spatial clustering of positive herds above that expected by chance alone. No analysis of risk factors was attempted for goats because of the paucity of positives.

  16. Modifications in the glycerophospholipid composition between the Coxiella burnetii phase I and phase II cells suggest an association with phase variation of the bacterium.

    PubMed

    Frimmelová, M; Toman, R; Pompach, P; Škultéty, L

    2016-03-01

    Glycerophospholipids (GP) extracted from the Coxiella burnetii strain Nine Mile in virulent phase I (NM I) and low virulent phase II (NM II) were analyzed by Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry (MS) that gave a superior mass resolution and mass accuracy allowing unambiguous peak recognition and precise assignment of ions. We showed that GP present in the pathogen's outer membrane underwent considerable modifications during the phase variation that might be related to impact of various environmental factors. It was found that GP from phase I cells were much more complex than those from phase II cells. While glycerophosphoethanolamines (PE), glycerophosphocholines (PC) and glycerophosphoglycerols (PG) were present in both phases of C. burnetii, major differences were observed in the presence of glycerophosphates (PA) and glycerophosphoserines (PS). Thus, PA but no PS were detected in NM I variant in contrast with NM II cells where PS but no PA were identified. It is suggested that enzymes for PA head group modifications to form PS, PE, and PG become active during the phase variation of the bacterium. PMID:26982464

  17. First Complete Genome Sequence of the Dutch Veterinary Coxiella burnetii Strain NL3262, Originating from the Largest Global Q Fever Outbreak, and Draft Genome Sequence of Its Epidemiologically Linked Chronic Human Isolate NLhu3345937

    PubMed Central

    Kuley, Runa; Smith, Hilde E.; Janse, Ingmar; Harders, Frank L.; Baas, Frank; Schijlen, Elio; Nabuurs-Franssen, Marrigje H.; Smits, Mari A.; Roest, Hendrik I. J.

    2016-01-01

    The largest global Q fever outbreak occurred in The Netherlands during 2007 to 2010. Goats and sheep were identified as the major sources of disease. Here, we report the first complete genome sequence of Coxiella burnetii goat outbreak strain NL3262 and that of an epidemiologically linked chronic human strain, both having the outbreak-related CbNL01 multilocus variable-number tandem-repeat analysis (MLVA) genotype. PMID:27103714

  18. A systematic review and meta-analysis of phase I inactivated vaccines to reduce shedding of Coxiella burnetii from sheep and goats from routes of public health importance.

    PubMed

    O'Neill, T J; Sargeant, J M; Poljak, Z

    2014-12-01

    Q fever in humans and coxiellosis in livestock are both caused by Coxiella burnetii. The public health importance of vaccination against C. burnetii shedding from sheep and goats was evaluated using systematic review and meta-analysis to provide evidence for policy direction to prevent potential zoonotic spread. Publications reporting shedding of C. burnetii in vaginal and uterine secretions, milk, placenta and faeces were included. A single observational (one goat) and seven experimental (four goat and three sheep) vaccine studies were included in the review. No relevant publications on other interventions were identified. Random effects meta-analyses were performed for the risk of shedding in individuals in the control and vaccinated groups and for the mean difference in the level of bacterial shedding in sheep and goats stratified by age and previous exposure status. Limited data were available for further analytic evaluation. From the pooled analysis, an inactivated phase I vaccine significantly reduced the risk of shedding from uterine (RR = 0.10; 95%CI 0.05-0.20) secretions in previously sensitized goats. Individual studies reported significant risk reduction in milk (RR = 0.03; 95%CI 0.01-0.26), vaginal secretions (RR = 0.40; 95%CI 0.22-0.75) and faeces (RR = 0.79; 95%CI 0.63-0.97) from naïve goats. The pooled mean levels of bacteria shed from placental [mean difference (MD = -5.24 Log10 ; 95%CI -6.75 to -3.7)] and vaginal (MD = -1.78 Log10 ; 95%CI -2.19 to -1.38) routes were significantly decreased in vaccinated naïve goats compared with controls. Shedding through all other routes from vaccinated goats was not significantly different than shedding from control goats. No effect of vaccination was found on the risk of shedding or the mean level of shedding in vaccinated sheep compared with control sheep. Our conclusions are based on a limited amount of data with variable risk of systematic error.

  19. Prevalence and risk factors for Campylobacter spp., Salmonella spp., Coxiella burnetii, and Newcastle disease virus in feral pigeons (Columba livia) in public areas of Montreal, Canada.

    PubMed

    Gabriele-Rivet, Vanessa; Fairbrother, Julie-Hélène; Tremblay, Donald; Harel, Josée; Côté, Nathalie; Arsenault, Julie

    2016-01-01

    Feral pigeons (Columbia livia) can harbor a range of zoonotic pathogens. A transversal study was undertaken to estimate the prevalence of feral pigeons infected by various pathogens in public areas in Montreal, Quebec. Cloacal swabs from captured birds were cultured for Salmonella spp. and Campylobacter spp. and tested by real-time polymerase chain reaction (RT-PCR) for the detection of Coxiella burnetii. An oropharyngeal swab was also submitted to real-time reverse-transcription polymerase chain reaction (RRT-PCR) for the detection of Newcastle disease virus. Among the 187 pigeons tested from 10 public areas, 9.1% (95% CI: 3.0 to 15.2) were positive for Campylobacter spp. with all strains identified as Campylobacter jejuni. The Campylobacter status of birds was not associated with individual characteristics of birds, with the exception of body score. None of the pigeons tested positive for the other pathogens. Direct or indirect contacts with feral pigeons may constitute a potential risk for Campylobacter infection in humans.

  20. Prevalence and risk factors for Campylobacter spp., Salmonella spp., Coxiella burnetii, and Newcastle disease virus in feral pigeons (Columba livia) in public areas of Montreal, Canada

    PubMed Central

    Gabriele-Rivet, Vanessa; Fairbrother, Julie-Hélène; Tremblay, Donald; Harel, Josée; Côté, Nathalie; Arsenault, Julie

    2016-01-01

    Feral pigeons (Columbia livia) can harbor a range of zoonotic pathogens. A transversal study was undertaken to estimate the prevalence of feral pigeons infected by various pathogens in public areas in Montreal, Quebec. Cloacal swabs from captured birds were cultured for Salmonella spp. and Campylobacter spp. and tested by real-time polymerase chain reaction (RT-PCR) for the detection of Coxiella burnetii. An oropharyngeal swab was also submitted to real-time reverse-transcription polymerase chain reaction (RRT-PCR) for the detection of Newcastle disease virus. Among the 187 pigeons tested from 10 public areas, 9.1% (95% CI: 3.0 to 15.2) were positive for Campylobacter spp. with all strains identified as Campylobacter jejuni. The Campylobacter status of birds was not associated with individual characteristics of birds, with the exception of body score. None of the pigeons tested positive for the other pathogens. Direct or indirect contacts with feral pigeons may constitute a potential risk for Campylobacter infection in humans. PMID:26733736

  1. Evaluation of Two PCR Tests for Coxiella burnetii Detection in Dairy Cattle Farms Using Latent Class Analysis

    PubMed Central

    Hoch, Thierry; Guatteo, Raphaël; Beaudeau, François

    2015-01-01

    Different tests performed on bulk tank milk samples (BTM) are available to determine the C. burnetii status of herds. However, these tests, which are based on the detection of either antibodies directed against C. burnetii (ELISA) or bacterial DNA (PCR), have limitations. A currently disease-free herd infected in the past may continue to test positive with ELISA due to the persistence of antibodies in animals that were infected and that subsequently cleared the infection. Infectious herds can also be misclassified using PCR because of the absence of bacteria in the BTM when the test is performed. Recently, PCR has been used for bacterial DNA detection in the farm environment, which constitutes the main reservoir of C. burnetii. The objectives of this study were to assess and compare the sensitivities and specificities of one commonly used PCR test in BTM (PCR BTM) and of a PCR applied to environmental samples (PCR DUST) in dairy cattle farms. BTM and dust samples were collected (using environmental swabs) in 95 herds. The evaluation of the performance of the 2 tests was conducted using latent class models accounting for within herd disease dynamics. Parameter estimation was carried out using MCMC, within a Bayesian framework. Two types of priors were used for the specificity of PCR DUST. A model with a uniform prior on 0–1 fitted the data better than a model with a uniform prior on 0.95–1. With the best model PCR DUST had a lower sensitivity than PCR BTM (0.75 versus 0.83) and a specificity of 0.72. The moderately low value for the specificity of PCR DUST suggests that the presence of bacteria on farm is not always associated with persistent infections and shedding of bacteria in milk. PMID:26673419

  2. Validation study for using lab-on-chip technology for Coxiella burnetii multi-locus-VNTR-analysis (MLVA) typing: application for studying genotypic diversity of strains from domestic ruminants in France.

    PubMed

    Prigent, Myriam; Rousset, Elodie; Yang, Elise; Thiéry, Richard; Sidi-Boumedine, Karim

    2015-01-01

    Coxiella burnetii, the etiologic bacterium of Q fever zoonosis, is still difficult to control. Ruminants are often carriers and involved in human epidemics. MLVA is a promising genotyping method for molecular epidemiology. Different techniques are used to resolve the MLVA band profiles such as electrophoresis on agarose gels, capillary electrophoresis or using the microfluidic Lab-on-Chip system. In this study, system based on microfluidics electrophoresis with Lab-on-Chip technology was assessed and applied on DNA field samples to investigate the genotypic diversity of C. burnetii strains circulating in France. The Lab-on-Chip technology was first compared to agarose gel electrophoresis. Subsequently, the set-up Lab-on-Chip technology was applied on 97 samples collected from ruminants in France using the 17 markers previously described. A discordance rate of 27% was observed between Lab-on-Chip and agarose gel electrophoresis. These discrepancies were checked and resolved by sequencing. The cluster analysis revealed classification based on host species and/or geographic origin criteria. Moreover, the circulation of different genotypic strains within the same farm was also observed. In this study, MLVA with Lab-on-Chip technology was shown to be more accurate, reproducible, user friendly and safer than gel electrophoresis. It also provides an extended data set from French ruminant C. burnetii circulating strains useful for epidemiological investigations. Finally, it raises some questions regarding the standardization and harmonization of C. burnetii MLVA genotyping.

  3. Sustained Axenic Metabolic Activity by the Obligate Intracellular Bacterium Coxiella burnetii▿ †

    PubMed Central

    Omsland, Anders; Cockrell, Diane C.; Fischer, Elizabeth R.; Heinzen, Robert A.

    2008-01-01

    Growth of Coxiella burnetii, the agent of Q fever, is strictly limited to colonization of a viable eukaryotic host cell. Following infection, the pathogen replicates exclusively in an acidified (pH 4.5 to 5) phagolysosome-like parasitophorous vacuole. Axenic (host cell free) buffers have been described that activate C. burnetii metabolism in vitro, but metabolism is short-lived, with bacterial protein synthesis halting after a few hours. Here, we describe a complex axenic medium that supports sustained (>24 h) C. burnetii metabolic activity. As an initial step in medium development, several biological buffers (pH 4.5) were screened for C. burnetii metabolic permissiveness. Based on [35S]Cys-Met incorporation, C. burnetii displayed optimal metabolic activity in citrate buffer. To compensate for C. burnetii auxotrophies and other potential metabolic deficiencies, we developed a citrate buffer-based medium termed complex Coxiella medium (CCM) that contains a mixture of three complex nutrient sources (neopeptone, fetal bovine serum, and RPMI cell culture medium). Optimal C. burnetii metabolism occurred in CCM with a high chloride concentration (140 mM) while the concentrations of sodium and potassium had little effect on metabolism. CCM supported prolonged de novo protein and ATP synthesis by C. burnetii (>24 h). Moreover, C. burnetii morphological differentiation was induced in CCM as determined by the transition from small-cell variant to large-cell variant. The sustained in vitro metabolic activity of C. burnetii in CCM provides an important tool to investigate the physiology of this organism including developmental transitions and responses to antimicrobial factors associated with the host cell. PMID:18310349

  4. Seroprevalence and Risk Factors for Coxiella burnetii (Q Fever) Seropositivity in Dairy Goat Farmers' Households in The Netherlands, 2009–2010

    PubMed Central

    Schimmer, Barbara; Lenferink, Anke; Schneeberger, Peter; Aangenend, Helen; Vellema, Piet; Hautvast, Jeannine; van Duynhoven, Yvonne

    2012-01-01

    Community Q fever epidemics occurred in the Netherlands in 2007–2009, with dairy goat and dairy sheep farms as the implicated source. The aim of the study was to determine the seroprevalence and risk factors for seropositivity in dairy goat farmers and their household members living or working on these farms. Sera of 268 people living or working on 111 dairy goat farms were tested for Coxiella burnetii IgG and IgM antibodies using immunofluorescence assay. Seroprevalences in farmers, spouses and children (12–17 years) were 73.5%, 66.7%, and 57.1%, respectively. Risk factors for seropositivity were: performing three or more daily goat-related tasks, farm location in the two southern provinces of the country, proximity to bulk milk-positive farms, distance from the nearest stable to residence of 10 meters or less, presence of cats and multiple goat breeds in the stable, covering stable air spaces and staff not wearing farm boots. Goat farmers have a high risk to acquire this occupational infection. Clinicians should consider Q fever in this population presenting with compatible symptoms to allow timely diagnosis and treatment to prevent severe sequelae. Based on the risk factors identified, strengthening general biosecurity measures is recommended such as consistently wearing boots and protective clothing by farm staff to avoid indirect transmission and avoiding access of companion animals in the goat stable. Furthermore, it provides an evidence base for continuation of the current vaccination policy for small ruminants, preventing spread from contaminated farms to other farms in the vicinity. Finally, vaccination of seronegative farmers and household members could be considered. PMID:22848762

  5. Coxiella-like endosymbiont associated to the "Anatolian brown tick" Rhipicephalus bursa in Southern Italy.

    PubMed

    Raele, Donato Antonio; Galante, Domenico; Pugliese, Nicola; De Simone, Esther; Cafiero, Maria Assunta

    2015-01-01

    Several different ticks have been reported to harbor microbes related to Coxiella burnetii, the agent of the Q fever. Rhipicephalus bursa is an important vector of tick-borne diseases in livestock in Mediterranean area; it is also abundant in ovi-caprine farms with C. burnetii infection, in Southern Italy. 60 females of Rh. bursa (15 pools) and 40 their eggs (2 pools) were screened for C. burnetii by a conventional PCR targeting the insertion sequence IS1111 and by Loop mediated isothermal amplification assay (LAMP) targeting com1 gene. One of 15 tick pools (1/15) and both egg pools (2/2) were found positive by LAMP assay and negative by PCR targeting IS1111 gene. 16S rRNA gene was amplified by PCR from the LAMP-positive pools, amplicons were sequenced and found 95% similar to the corresponding sequences from C. burnetii. This let us to hypothesize the presence of a new Coxiella-like endosymbiont associated with Rh. bursa which could be vertically transmitted, described here for the first time. The lack of detection of IS1111 in Coxiella endosymbiont of Rh. bursa could be related to the possible absence of the Pathogenicity island of C. burnetii, to which IS1111s are associated.

  6. Prevalence and molecular typing of Coxiella burnetii in bulk tank milk in Belgian dairy goats, 2009-2013.

    PubMed

    Boarbi, Samira; Mori, Marcella; Rousset, Elodie; Sidi-Boumedine, Karim; Van Esbroeck, Marjan; Fretin, David

    2014-05-14

    Q fever, a worldwide zoonosis, is an arousing public health concern in many countries since the recent Dutch outbreak. An emerging C. burnetii clone, genotype CbNL01, was identified as responsible for the Dutch human Q fever cluster cases. Since 2009, Q fever surveillance in the goat industry was implemented by the Belgian authorities. The herd prevalence (December 2009-March 2013) ranged between 6.3 and 12.1%. Genotypic analysis highlighted the molecular diversity of the Belgian strains from goats and identified an emerging CbNL01-like genotype. This follow-up allowed the description of shedding profiles in positive farms which was either continuous (type I) and associated to the CbNL01-like genotype; or intermittent (type II) and linked to other genotypes. Despite the circulation of a CbNL01-like strain, the number of notified Belgian human cases was very low. The mandatory vaccination (in June 2011) on positive dairy goat farms in Belgium, contributed to a decrease in shedding.

  7. Evaluation of qPCR and phase I and II antibodies for detection of Coxiella burnetii infection in cattle.

    PubMed

    Szymańska-Czerwińska, Monika; Niemczuk, Krzysztof; Jodełko, Agnieszka

    2016-10-01

    Diagnosis of Q fever in cattle is not easy due to the need to test the samples by both serological and molecular methods. Aim of this study was to evaluate qPCR, and phase I and II antibodies for detection of C. burnetii infection in cattle. A total of 187 bovine blood and vaginal swabs, and 97 milk samples, were tested. Limitations of serological tests were that the available indirect enzyme linked immunosorbent assay (iELISA) could lose positive results if antibody titres were low; or phase II antibodies were present. The highest level of correlation between iELISA and complement fixation test (CFT) was noted with the antigen specific phase I antibodies. Neither the mode of shedding nor its intensity correlated with phase I and II antibodies, but positive results in CFT mixed-phase and shedding in vaginal mucous did correlate, and showed the highest correlation. Antigenic diversity, and variability could be crucial in laboratory diagnosis of Q fever. PMID:27663372

  8. Complement fixation test to C burnetii

    MedlinePlus

    ... due to bacterium called C burnetii, which causes Q fever . ... eds. Henry's Clinical Diagnosis and Management by Laboratory ... Coxiella burnetti (Q fever). In: Bennett JE, Dolin R, Blaser MJ, ...

  9. The Effect of C. burnetii Infection on the Cytokine Response of PBMCs from Pregnant Goats

    PubMed Central

    Ammerdorffer, Anne; Roest, Hendrik-I J.; Dinkla, Annemieke; Post, Jacob; Schoffelen, Teske; van Deuren, Marcel; Sprong, Tom; Rebel, Johanna M.

    2014-01-01

    In humans, infection with Coxiella burnetii, the causative agent of Q fever, leads to acute or chronic infection, both associated with specific clinical symptoms. In contrast, no symptoms are observed in goats during C. burnetii infection, although infection of the placenta eventually leads to premature delivery, stillbirth and abortion. It is unknown whether these differences in clinical outcome are due to the early immune responses of the goats. Therefore, peripheral blood mononuclear cells (PBMCs) were isolated from pregnant goats. In total, 17 goats were included in the study. Six goats remained naive, while eleven goats were infected with C. burnetii. Toll-like receptor (TLR) and cytokine mRNA expression were measured after in vitro stimulation with heat-killed C. burnetii at different time points (prior infection, day 7, 35 and 56 after infection). In naive goats an increased expression of interleukin (IL)-1β, tumor necrosis factor (TNF)-α, IL-10 and interferon (IFN)-γ mRNA upon C. burnetii stimulation was detected. In addition, TLR2 expression was strongly up-regulated. In goats infected with C. burnetii, PBMCs re-stimulated in vitro with C. burnetii, expressed significantly more TNF-α mRNA and IFN-γ mRNA compared to naive goats. In contrast, IL-10 mRNA production capacity was down-regulated during C. burnetii infection. Interestingly, at day 7 after inoculation a decreased IFN-γ protein level was observed in stimulated leukocytes in whole blood from infected goats, whereas at other time-points increased production of IFN-γ protein was seen. Our study shows that goats initiate a robust pro-inflammatory immune response against C. burnetii in vitro. Furthermore, PBMCs from C. burnetii infected goats show augmented pro-inflammatory cytokine responses compared to PBMCs from non-infected goats. However, despite this pro-inflammatory response, goats are not capable of clearing the C. burnetii infection. PMID:25279829

  10. The effect of C. burnetii infection on the cytokine response of PBMCs from pregnant goats.

    PubMed

    Ammerdorffer, Anne; Roest, Hendrik-I J; Dinkla, Annemieke; Post, Jacob; Schoffelen, Teske; van Deuren, Marcel; Sprong, Tom; Rebel, Johanna M

    2014-01-01

    In humans, infection with Coxiella burnetii, the causative agent of Q fever, leads to acute or chronic infection, both associated with specific clinical symptoms. In contrast, no symptoms are observed in goats during C. burnetii infection, although infection of the placenta eventually leads to premature delivery, stillbirth and abortion. It is unknown whether these differences in clinical outcome are due to the early immune responses of the goats. Therefore, peripheral blood mononuclear cells (PBMCs) were isolated from pregnant goats. In total, 17 goats were included in the study. Six goats remained naive, while eleven goats were infected with C. burnetii. Toll-like receptor (TLR) and cytokine mRNA expression were measured after in vitro stimulation with heat-killed C. burnetii at different time points (prior infection, day 7, 35 and 56 after infection). In naive goats an increased expression of interleukin (IL)-1β, tumor necrosis factor (TNF)-α, IL-10 and interferon (IFN)-γ mRNA upon C. burnetii stimulation was detected. In addition, TLR2 expression was strongly up-regulated. In goats infected with C. burnetii, PBMCs re-stimulated in vitro with C. burnetii, expressed significantly more TNF-α mRNA and IFN-γ mRNA compared to naive goats. In contrast, IL-10 mRNA production capacity was down-regulated during C. burnetii infection. Interestingly, at day 7 after inoculation a decreased IFN-γ protein level was observed in stimulated leukocytes in whole blood from infected goats, whereas at other time-points increased production of IFN-γ protein was seen. Our study shows that goats initiate a robust pro-inflammatory immune response against C. burnetii in vitro. Furthermore, PBMCs from C. burnetii infected goats show augmented pro-inflammatory cytokine responses compared to PBMCs from non-infected goats. However, despite this pro-inflammatory response, goats are not capable of clearing the C. burnetii infection. PMID:25279829

  11. Bayesian Validation of the Indirect Immunofluorescence Assay and Its Superiority to the Enzyme-Linked Immunosorbent Assay and the Complement Fixation Test for Detecting Antibodies against Coxiella burnetii in Goat Serum.

    PubMed

    Muleme, Michael; Stenos, John; Vincent, Gemma; Campbell, Angus; Graves, Stephen; Warner, Simone; Devlin, Joanne M; Nguyen, Chelsea; Stevenson, Mark A; Wilks, Colin R; Firestone, Simon M

    2016-06-01

    Although many studies have reported the indirect immunofluorescence assay (IFA) to be more sensitive in detection of antibodies to Coxiella burnetii than the complement fixation test (CFT), the diagnostic sensitivity (DSe) and diagnostic specificity (DSp) of the assay have not been previously established for use in ruminants. This study aimed to validate the IFA by describing the optimization, selection of cutoff titers, repeatability, and reliability as well as the DSe and DSp of the assay. Bayesian latent class analysis was used to estimate diagnostic specifications in comparison with the CFT and the enzyme-linked immunosorbent assay (ELISA). The optimal cutoff dilution for screening for IgG and IgM antibodies in goat serum using the IFA was estimated to be 1:160. The IFA had good repeatability (>96.9% for IgG, >78.0% for IgM), and there was almost perfect agreement (Cohen's kappa > 0.80 for IgG) between the readings reported by two technicians for samples tested for IgG antibodies. The IFA had a higher DSe (94.8%; 95% confidence interval [CI], 80.3, 99.6) for the detection of IgG antibodies against C. burnetii than the ELISA (70.1%; 95% CI, 52.7, 91.0) and the CFT (29.8%; 95% CI, 17.0, 44.8). All three tests were highly specific for goat IgG antibodies. The IFA also had a higher DSe (88.8%; 95% CI, 58.2, 99.5) for detection of IgM antibodies than the ELISA (71.7%; 95% CI, 46.3, 92.8). These results underscore the better suitability of the IFA than of the CFT and ELISA for detection of IgG and IgM antibodies in goat serum and possibly in serum from other ruminants.

  12. Bayesian Validation of the Indirect Immunofluorescence Assay and Its Superiority to the Enzyme-Linked Immunosorbent Assay and the Complement Fixation Test for Detecting Antibodies against Coxiella burnetii in Goat Serum.

    PubMed

    Muleme, Michael; Stenos, John; Vincent, Gemma; Campbell, Angus; Graves, Stephen; Warner, Simone; Devlin, Joanne M; Nguyen, Chelsea; Stevenson, Mark A; Wilks, Colin R; Firestone, Simon M

    2016-06-01

    Although many studies have reported the indirect immunofluorescence assay (IFA) to be more sensitive in detection of antibodies to Coxiella burnetii than the complement fixation test (CFT), the diagnostic sensitivity (DSe) and diagnostic specificity (DSp) of the assay have not been previously established for use in ruminants. This study aimed to validate the IFA by describing the optimization, selection of cutoff titers, repeatability, and reliability as well as the DSe and DSp of the assay. Bayesian latent class analysis was used to estimate diagnostic specifications in comparison with the CFT and the enzyme-linked immunosorbent assay (ELISA). The optimal cutoff dilution for screening for IgG and IgM antibodies in goat serum using the IFA was estimated to be 1:160. The IFA had good repeatability (>96.9% for IgG, >78.0% for IgM), and there was almost perfect agreement (Cohen's kappa > 0.80 for IgG) between the readings reported by two technicians for samples tested for IgG antibodies. The IFA had a higher DSe (94.8%; 95% confidence interval [CI], 80.3, 99.6) for the detection of IgG antibodies against C. burnetii than the ELISA (70.1%; 95% CI, 52.7, 91.0) and the CFT (29.8%; 95% CI, 17.0, 44.8). All three tests were highly specific for goat IgG antibodies. The IFA also had a higher DSe (88.8%; 95% CI, 58.2, 99.5) for detection of IgM antibodies than the ELISA (71.7%; 95% CI, 46.3, 92.8). These results underscore the better suitability of the IFA than of the CFT and ELISA for detection of IgG and IgM antibodies in goat serum and possibly in serum from other ruminants. PMID:27122484

  13. The genome of Coxiella burnetii Z3055, a clone linked to the Netherlands Q fever outbreaks, provides evidence for the role of drift in the emergence of epidemic clones.

    PubMed

    D'Amato, Felicetta; Rouli, Laetitia; Edouard, Sophie; Tyczka, Judith; Million, Matthieu; Robert, Catherine; Nguyen, Thi Tien; Raoult, Didier

    2014-12-01

    Coxiella burnetii is a pathogen causing Q fever. The aim of our work was to study Z3055, a strain that is genotypically related to the strain causing the Netherlands outbreak. We compared Z3055 to 5 other completed genomes available in GenBank. We calculated the blast score ratio (BSR) to analyze genetic differences among the strains. The ratio core genome/pangenome was 98% likely other bacteria with closed pangenomes. Differences between Z3055 and the reference NMI consisted only of point mutations and insertion/deletion (INDELs). Non-synonymous mutations significantly increased in genes coding for membrane proteins (16/156 vs 103/1757, bilateral Chi(2) test, p<0.05), ankyrin repeat domains containing proteins (2/9 vs 117/1904, bilateral Chi(2) test, p<0.05), transcription factors (7/53 vs 112/1860, bilateral Chi(2) test, p<0.05) and translation proteins (15/144 vs 109/1655, bilateral Chi(2) test, p<0.05). The evolution of this strain may have been driven by mutations in critical genes.

  14. Serological survey of Bartonella spp., Borrelia burgdorferi, Brucella spp., Coxiella burnetii, Francisella tularensis, Leptospira spp., Echinococcus, Hanta-, TBE- and XMR-virus infection in employees of two forestry enterprises in North Rhine-Westphalia, Germany, 2011-2013.

    PubMed

    Jurke, Annette; Bannert, N; Brehm, K; Fingerle, V; Kempf, V A J; Kömpf, D; Lunemann, M; Mayer-Scholl, A; Niedrig, M; Nöckler, K; Scholz, H; Splettstoesser, W; Tappe, D; Fischer, Silke F

    2015-10-01

    We initiated a survey to collect basic data on the frequency and regional distribution of various zoonoses in 722 employees of forestry enterprises in the German state of North Rhine-Westphalia (NRW) from 2011 to 2013. Exposures associated with seropositivity were identified to give insight into the possible risk factors for infection with each pathogen. 41.2% of participants were found to be seropositive for anti-Bartonella IgG, 30.6% for anti-Borrelia burgdorferi IgG, 14.2% for anti-Leptospira IgG, 6.5% for anti-Coxiella burnetii IgG, 6.0% for anti-Hantavirus IgG, 4.0% for anti-Francisella tularensis IgG, 3.4% for anti-TBE-virus IgG, 1.7% for anti-Echinococcus IgG, 0.0% for anti-Brucella IgG and anti-XMRV IgG. Participants seropositive for B. burgdorferi were 3.96 times more likely to be professional forestry workers (univariable analysis: OR 3.96; 95% CI 2.60-6.04; p<0.001); and participants seropositive for Hantavirus 3.72 times more likely (univariable analysis: OR 3.72; 95% CI 1.44-9.57; p=0.007). This study found a surprisingly high percentage of participants seropositive for anti-B. henselae IgG and for anti-F. tularensis IgG. The relatively high seroprevalence for anti-Leptospira IgG seen in this study could be related to living conditions rather than to exposure at work. No specific risk for exposure to C. burnetii and Echinococcus was identified, indicating that neither forestry workers nor office workers represent a risk population and that NRW is not a typical endemic area. Forestry workers appear to have higher risk for contact with B. burgdorferi-infected ticks and a regionally diverse risk for acquiring Hantavirus-infection. The regional epidemiology of zoonoses is without question of great importance for public health. Knowledge of the regional risk factors facilitates the development of efficient prevention strategies and the implementation of such prevention measures in a sustainable manner.

  15. Detection of Coxiella burnetti by DNA amplification using polymerase chain reaction.

    PubMed Central

    Stein, A; Raoult, D

    1992-01-01

    The polymerase chain reaction (PCR) was used for the detection of Coxiella burnetti, an obligate intracellular bacterium and the etiologic agent of Q fever. A pair of primers derived from the C. burnetii superoxide dismutase gene served to amplify a targeted 257-bp fragment of genomic DNA. These primers were chosen on the basis of GenBank analysis, G + C ratio, and absence of secondary structure. This technique allowed the detection of as few as 10 C. burnetii organisms. C. burnetti was detected in tissue culture and in specimens from patients (heart valves). In all, 8 reference isolates and 22 new isolates of C. burnetii from France were successfully amplified. No amplification products were found when PCR was performed with 25 bacterial species that had been isolated in a clinical laboratory from patients with clinically similar infections. Amplification products of C. burnetii were confirmed by restriction enzyme digestion and dot blot hybridization. The method used here, a combination of PCR and restriction analysis, is a faster and more sensitive assay for C. burnetii than standard culture techniques. Images PMID:1401016

  16. Coxiella Type IV Secretion and Cellular Microbiology

    PubMed Central

    Voth, Daniel E.; Heinzen, Robert A.

    2009-01-01

    Summary Coxiella burnetii is a wide spread zoonotic bacterial pathogen that causes human Q fever. In vivo, Coxiella displays a tropism for mononuclear phagocytes where it participates in biogenesis of a lysosome-like replication compartment to conduct its obligate intracellular lifestyle. Coxiella actively regulates multiple events during infection, presumably via proteins with effector functions that are delivered to the host cytosol by a Dot/Icm type IV secretion system. Because the organism is currently refractory to genetic manipulation, Coxiella Dot/Icm substrates have been identified using bioinformatics and Legionella pneumophila as a surrogate type IV delivery system. Functional characterization of the biological activity of these effector proteins will dramatically aid our ability to model Coxiella-host cell interactions. PMID:19144560

  17. Coxiella subversion of intracellular host signaling.

    PubMed

    Hussain, S Kauser; Voth, Daniel E

    2012-01-01

    Coxiella burnetii is a highly infectious bacterial pathogen that replicates in a specialized vacuole inside eukaryotic cells. Due to a prolonged growth cycle, Coxiella continuously manipulates cellular processes to generate this parasitophorous vacuole (PV) and promote host cell viability. Here, we discuss recent findings that indicate Coxiella modulates several host signaling pathways to influence survival and ensure intracellular replication. The pathogen actively inhibits apoptotic cell death and activates the pro-survival kinases Akt and Erk1/2 to promote host viability. Coxiella's anti-apoptotic activity also involves the interface between autophagy and apoptosis, which is regulated by the interaction of autophagy-related Beclin-1 and anti-apoptotic Bcl-2. Additionally, Coxiella requires host kinase activity for PV biogenesis and maintenance. Thus, signaling modulation by Coxiella is critical for multiple aspects of host cell parasitism. Collectively, recent signaling studies have enhanced our understanding of the unique Coxiella-host cell interaction. Identification of bacterial factors that regulate signaling events will further our ability to model this intriguing infectious process.

  18. Rhipicephalus ticks infected with Rickettsia and Coxiella in Southern Switzerland (Canton Ticino).

    PubMed

    Bernasconi, Marco V; Casati, Simona; Péter, Olivier; Piffaretti, Jean-Claude

    2002-12-01

    Ticks of the Rhipicephalus sanguineus species complex may be vector of various pathogens including Rickettsia conorii (the etiological agent of the Mediterranean spotted fever) and Coxiella burnetii (cause of the Query (Q) fever). R. sanguineus ticks have been imported in several parts of central and northern Europe, especially in environments such as kennels and houses providing the appropriate microclimatic conditions and the blood source necessary for their survival. Since 1940 these ticks have occasionally been recorded in Switzerland. In Ticino (the southern part of Switzerland), they have been reported since 1980 and their probable establishment in this area has been suggested in the '90s. By means of PCR and direct sequencing, we tested the identity of these ticks (using 12S rDNA gene) and the occurrence of Rickettsia spp. (using 16S rDNA, gltA and OmpA genes) as well as Coxiella sp. (using 16S rDNA). The results indicated that in Ticino, two different tick species coexist, i.e. R. sanguineus sensu stricto and Rhipicephalus turanicus. A few individuals of R. sanguineus sensu stricto are infected with Rickettsia massiliae/Bar29, which are strains of unknown pathogenicity. Coxiella sp., an endosymbiont of Rhipicephalus ticks, has also been identified in both tick species. Due to climatic changes towards global warming, imported tick species may therefore adapt to new area and might be considered as epidemiological markers for a number of infectious agents transmitted by them.

  19. Coxiella-like endosymbiont in argasid ticks (Ornithodoros muesebecki) from a Socotra Cormorant colony in Umm Al Quwain, United Arab Emirates.

    PubMed

    Al-Deeb, Mohammad A; Frangoulidis, Dimitrios; Walter, Mathias C; Kömpf, Daniela; Fischer, Silke F; Petney, Trevor; Muzaffar, Sabir Bin

    2016-02-01

    Coxiella burnetii is a pathogen causing Q fever in domestic animals and humans. Seabirds have been implicated as possible reservoirs of this bacterium in the Arabian Gulf and in the Western Indian Ocean. Recently, Coxiella species closely related to C. burnetii was detected from ticks collected from oil rigs used as roosting areas by Socotra Cormorants (Phalacrocorax nigrogularis) in the western Arabian Gulf. We collected ticks from the largest breeding colony of Socotra Cormorants in the United Arab Emirates on the eastern extreme of the species' breeding range to determine the prevalence of C. burnetii and evaluate its role as a wild reservoir. All ticks were identified as Ornithodoros muesebecki and genomic DNA was extracted from larval and nymph/adult tick pools. Multiplex PCR tests were performed targeting three C. burnetii specific genes. C. burnetii was not detected although a Coxiella-like endosymbiont was identified that was closely related to Coxiella symbionts from Ornithodoros capensis ticks. Because domestic and wild ungulates are the primary source of C. burnetii, we suggest that the presence of free-ranging, native and non-native ungulates in some off-shore islands in the Arabian Gulf could disseminate C. burnetii to seabirds. More comprehensive studies on seabird colonies are needed to better understand the diversity and prevalence of Coxiella symbionts and to establish if C. burnetii is endemic on some of these islands.

  20. Coxiella-like endosymbiont in argasid ticks (Ornithodoros muesebecki) from a Socotra Cormorant colony in Umm Al Quwain, United Arab Emirates.

    PubMed

    Al-Deeb, Mohammad A; Frangoulidis, Dimitrios; Walter, Mathias C; Kömpf, Daniela; Fischer, Silke F; Petney, Trevor; Muzaffar, Sabir Bin

    2016-02-01

    Coxiella burnetii is a pathogen causing Q fever in domestic animals and humans. Seabirds have been implicated as possible reservoirs of this bacterium in the Arabian Gulf and in the Western Indian Ocean. Recently, Coxiella species closely related to C. burnetii was detected from ticks collected from oil rigs used as roosting areas by Socotra Cormorants (Phalacrocorax nigrogularis) in the western Arabian Gulf. We collected ticks from the largest breeding colony of Socotra Cormorants in the United Arab Emirates on the eastern extreme of the species' breeding range to determine the prevalence of C. burnetii and evaluate its role as a wild reservoir. All ticks were identified as Ornithodoros muesebecki and genomic DNA was extracted from larval and nymph/adult tick pools. Multiplex PCR tests were performed targeting three C. burnetii specific genes. C. burnetii was not detected although a Coxiella-like endosymbiont was identified that was closely related to Coxiella symbionts from Ornithodoros capensis ticks. Because domestic and wild ungulates are the primary source of C. burnetii, we suggest that the presence of free-ranging, native and non-native ungulates in some off-shore islands in the Arabian Gulf could disseminate C. burnetii to seabirds. More comprehensive studies on seabird colonies are needed to better understand the diversity and prevalence of Coxiella symbionts and to establish if C. burnetii is endemic on some of these islands. PMID:26515059

  1. First Complete Genome Sequence of the Dutch Veterinary Coxiella burnetii Strain NL3262, Originating from the Largest Global Q Fever Outbreak, and Draft Genome Sequence of Its Epidemiologically Linked Chronic Human Isolate NLhu3345937.

    PubMed

    Kuley, Runa; Smith, Hilde E; Janse, Ingmar; Harders, Frank L; Baas, Frank; Schijlen, Elio; Nabuurs-Franssen, Marrigje H; Smits, Mari A; Roest, Hendrik I J; Bossers, Alex

    2016-01-01

    The largest global Q fever outbreak occurred in The Netherlands during 2007 to 2010. Goats and sheep were identified as the major sources of disease. Here, we report the first complete genome sequence of ITALIC! Coxiella burnetiigoat outbreak strain NL3262 and that of an epidemiologically linked chronic human strain, both having the outbreak-related ITALIC! CbNL01multilocus variable-number tandem-repeat analysis (MLVA) genotype. PMID:27103714

  2. Pathogenic rickettsiae as bioterrorism agents.

    PubMed

    Azad, Abdu F

    2007-07-15

    Because of their unique biological characteristics, such as environmental stability, small size, aerosol transmission, persistence in infected hosts, low infectious dose, and high associated morbidity and mortality, Rickettsia prowazekii and Coxiella burnetii have been weaponized. These biological attributes would make the pathogenic rickettsiae desirable bioterrorism agents. However, production of highly purified, virulent, weapon-quality rickettsiae is a daunting task that requires expertise and elaborate, state-of-the art laboratory procedures to retain rickettsial survival and virulence. Another drawback to developing rickettsial pathogens as biological weapons is their lack of direct transmission from host to host and the availability of very effective therapeutic countermeasures against these obligate intracellular bacteria.

  3. Inactivation of Coxiella burnetti by gamma irradiation

    SciTech Connect

    Scott, G.H.; McCaul, T.F.; Williams, J.C.

    1989-01-01

    The gamma radiation inactivation kinetics for Coxiella burnetii at - 79 C were exponential. The radiation dose needed to reduce the number of infective C. burnetii by 90% varied from 0-64 to 1.2 kGy depending on the phase of hte micro-organism, purity of the culture and composition of suspending menstruum. The viability of preparations containing C. burnetti was completely abolished by 10 kGy without diminishing antigenicity or ability to elicit a protective immune response in vaccinated mice. Immunocytochemical examinations using monoclonal antibodies and electron microscopy demonstrated that radiation doses of 20 kGy did not alter cell-wall morphology or cell-surface antigenic epitopes.

  4. HoPaCI-DB: host-Pseudomonas and Coxiella interaction database

    PubMed Central

    Bleves, Sophie; Dunger, Irmtraud; Walter, Mathias C.; Frangoulidis, Dimitrios; Kastenmüller, Gabi; Voulhoux, Romé; Ruepp, Andreas

    2014-01-01

    Bacterial infectious diseases are the result of multifactorial processes affected by the interplay between virulence factors and host targets. The host-Pseudomonas and Coxiella interaction database (HoPaCI-DB) is a publicly available manually curated integrative database (http://mips.helmholtz-muenchen.de/HoPaCI/) of host–pathogen interaction data from Pseudomonas aeruginosa and Coxiella burnetii. The resource provides structured information on 3585 experimentally validated interactions between molecules, bioprocesses and cellular structures extracted from the scientific literature. Systematic annotation and interactive graphical representation of disease networks make HoPaCI-DB a versatile knowledge base for biologists and network biology approaches. PMID:24137008

  5. Detection of Lyme Disease and Q Fever Agents in Wild Rodents in Central Italy

    PubMed Central

    Di Domenico, Marco; Dall'Acqua, Francesca; Sozio, Giulia; Cammà, Cesare

    2015-01-01

    Abstract The maintenance of tick-borne disease agents in the environment strictly depends on the relationship between tick vectors and their hosts, which act as reservoirs for these pathogens. A pilot study aimed to investigate wild rodents as reservoirs for zoonotic tick-borne pathogens (Borrelia burgdorferi sensu lato (s.l.), Coxiella burnetii, Francisella tularensis, and Anaplasma phagocytophilum) was carried out in an area of Gran Sasso e Monti della Laga National Park (Abruzzi Region, central Italy), a wide protected area where, despite sporadic reports of infection in humans and animals, eco-epidemiological data on these diseases are still not available. Rodents were trapped and released at the capture site after the collection of feeding ticks and blood samples. In all, 172 ticks were collected; the most frequent species was Ixodes acuminatus (53%). Out of 88 tick pools, 11 resulted positive for C. burnetii and 13 for B. burgdorferi s.l.; the Borrelia afzelii genospecies was identified in one Ixodes ricinus tick collected from one Apodemus sp. rodent. Out of 143 blood samples, seven Apodemus spp. and five Myodes glareolus were positive for B. burgdorferi s.l. and two Apodemus spp. were positive for C. burnetii. All samples (ticks and blood) were negative for F. tularensis and A. phagocytophilum. This is the first report of B. burgdorferi s.l. in the environment for Abruzzi Region. Data on the presence of B. burgdorferi s.l. are similar to that observed in other Mediterranean countries. The present work is also the first report of C. burnetii in wild rodents in Italy. C. burnetii infection has been largely investigated in Italy in ruminant farms by serology and molecular methods, but information on ecology and on the wild cycle are still lacking. Further studies including genotyping should be performed and species-specific differences between wild rodent reservoirs of Q fever and Lyme disease agents should be investigated. PMID:26134933

  6. Lipopolysaccharide variation in Coxiella burnetti: intrastrain heterogeneity in structure and antigenicity.

    PubMed Central

    Hackstadt, T; Peacock, M G; Hitchcock, P J; Cole, R L

    1985-01-01

    We isolated lipopolysaccharides (LPSs) from phase variants of Coxiella burnetii Nine Mile and compared the isolated LPS and C. burnetii cells by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting. The LPSs were found to be the predominant component which varied structurally and antigenically between virulent phase I and avirulent phase II. A comparison of techniques historically used to extract the phase I antigenic component revealed that the aqueous phase of phenol-water, trichloroacetic acid, and dimethyl sulfoxide extractions of phase I C. burnettii cells all contained phase I LPS, although the efficiency and specificity of extraction varied. Our studies provide additional evidence that phase variation in C. burnetii is analogous to the smooth-to-rough LPS variation of gram-negative enteric bacteria, with phase I LPS being equivalent to smooth LPS and phase II being equivalent to rough LPS. In addition, we identified a variant with a third LPS chemotype with appears to have a structural complexity intermediate to phase I and II LPSs. All three C. burnetii LPS contain a 2-keto-3-deoxyoctulosonic acid-like substance, heptose, and gel Limulus amoebocyte lysates in subnanogram amounts. The C. burnetii LPSs were nontoxic to chicken embryos at doses of over 80 micrograms per embryo, in contrast to Salmonella typhimurium smooth- and rough-type LPSs, which were toxic in nanogram amounts. Images PMID:3988339

  7. Molecular detection of Rickettsia, Anaplasma, Coxiella and Francisella bacteria in ticks collected from Artiodactyla in Thailand.

    PubMed

    Sumrandee, Chalao; Baimai, Visut; Trinachartvanit, Wachareeporn; Ahantarig, Arunee

    2016-07-01

    A total of 79 ticks collected from Sambar deer (Cervus unicolor), Barking deer (Muntiacus muntjak) and Wild boar (Sus scrofa) were examined by PCR for the presence of Rickettsia, Anaplasma, Coxiella, and Francisella bacteria. Of the 79 ticks, 13% tested positive for Rickettsia, 15% tested positive for Anaplasma, 4% tested positive for Coxiella, and 3% tested positive for Francisella. Interestingly, triple infection with Anaplasma, Rickettsia and Francisella was determined in a Dermacentor auratus tick. Moreover, another triple infection with Rickettsia, Anaplasma, and Coxiella was found in a Haemaphysalis lagrangei tick. Double infection of Rickettsia with Coxiella was also detected in another H. lagrangei tick. From the phylogenetic analyses, we found a Rickettsia sp. with a close evolutionary relationship to Rickettsia bellii in the H. lagrangei tick. We also found the first evidence of a Rickettsia sp. that is closely related to Rickettsia tamurae in Rhipicephalus (Boophilus) microplus ticks from Thailand. H. lagrangei and Haemaphysalis obesa ticks collected from Sambar deer tested positive for Anaplasma species form the same clade with Anaplasma bovis. In contrast, other H. lagrangei ticks collected from Sambar deer and D. auratus ticks collected from Wild boar were also reported for the first time to be infected with an Anaplasma species that is closely related to Anaplasma platys. The phylogenetic analysis of the 16S rRNA gene of Coxiella bacteria revealed that Coxiella symbionts from H. lagrangei formed a distinctly different lineage from Coxiella burnetii (a human pathogen). Additionally, Francisella bacteria identified in D. auratus ticks were found to be distantly related to a group of pathogenic Francisella species. The identification of these bacteria in several feeding ticks suggests the risk of various emerging tick-borne diseases and endosymbionts in humans, wildlife, and domestic animals in Thailand. PMID:26934997

  8. A heat shock operon in Coxiella burnetti produces a major antigen homologous to a protein in both mycobacteria and Escherichia coli.

    PubMed Central

    Vodkin, M H; Williams, J C

    1988-01-01

    A gene library from the DNA of Coxiella burnetii has been constructed in the cosmid vector pHC79. A particular clone, pJB196, reacted strongly with Coxiella-specific antibodies elicited in a number of different species of animals. This clone produced two abundant C. burnetii-specific polypeptides, a 14-kilodalton nonimmunoreactive protein and a 62-kilodalton immunoreactive protein. Sequencing identified two open reading frames, encoding polypeptides of 10.5 and 58.3 kilodaltons. The only transcriptional control element observed on the 5' side of the initiation codon resembled a heat shock promoter. This heat shock promoter was functionally regulated in Escherichia coli, since both proteins were produced by growth conditions at 37 degrees C and neither protein was detected at 23 degrees C. There were four sequences from the literature that were highly homologous (greater than 50%) to the 62-kilodalton protein from C. burnetii. Three were from Mycobacterium species and represent the immunodominant antigen of this genus. The other was from E. coli, detected as a gene that complements or suppresses a temperature-sensitive RNase activity. Since the recombinant protein was immunogenic, it may serve as an efficacious vaccine against C. burnetii and other pathogenic microorganisms that express the conserved antigen. Images PMID:3343219

  9. Molecular Detection and Genotyping of Coxiella-Like Endosymbionts in Ticks that Infest Horses in South Korea

    PubMed Central

    Seo, Min-Goo; Lee, Seung-Hun; Ouh, In-Ohk; Lee, Gwang Hyeop; Goo, Youn-Kyoung; Kim, Seungjoon; Kwon, Oh-Deog

    2016-01-01

    Members of the genus Coxiella can be transmitted from ticks to humans during contact with animals; Coxiella may thus spread from the infected horses or ticks to humans. In this study, the presence of Coxiella burnetii and Coxiella-like endosymbionts (CLE) in ticks found on infested horses was determined using PCR and genotyping. A total of 213 ticks were randomly collected from 51 horses (4–5 ticks per horse) raised on Jeju Island, Korea, between 2009 and 2013. All ticks were morphologically identified as adult Haemaphysalis longicornis, a predominant tick species widespread in Korea. Based on the results of nested PCR and 16S rRNA sequencing, CLE were detected in 121 (52.4%, 95% CI: 45.9–58.8) ticks. CLE 16S rRNA sequences from 9 randomly selected ticks were 100% identical. Phylogenetic analysis showed that these 9 sequences were highly similar (97.9–100%) to the sequences of clade B species, like the CLE previously described to be found in Haemaphysalis spp. This study showed that CLE are prevalent in ticks that infest horses reared on Jeju Island, and this is, to the best of our knowledge, the first study to describe CLE occurrence in ticks infesting animals reared in Korea. Because of the high prevalence of CLE in ticks found on horses, CLE transmission from ticks to other animals and humans remains a possibility. This warrants a detailed study of other hosts and regions. Considering the zoonotic potential of Coxiella, further strategic surveillance of Coxiella transmission is necessary. PMID:27792764

  10. In vitro studies of interaction of rickettsia and macrophages: effect of ultraviolet light on Coxiella burnetti inactivation and macrophage enzymes

    SciTech Connect

    Little, J.S.; Kishimoto, R.A.; Canonico, P.G.

    1980-03-01

    The inactivation of Coxiella burnetii in suspension or in cultures of guinea pig peritoneal macrophages by ultraviolet (uv) light was studied. The effect of uv treatment on the activity of macrophage organelle marker enzymes and their subsequent equilibration in linear sucrose gradients was also determined. It was shown that uv treatment for 15 s at a distance of 10 cm inactivated C. burnetti, either in suspension or within guinea pig peritoneal macrophages. Similar uv treatment had little effect on the activity or equilibration of macrophage organelle marker enzymes in linear sucrose gradients.

  11. Microbiological and parasitological survey of zoonotic agents in apparently healthy feral pigeons.

    PubMed

    Marenzoni, M L; Morganti, G; Moretta, I; Crotti, S; Agnetti, F; Moretti, A; Pitzurra, L; Casagrande Proietti, P; Sechi, P; Cenci-Goga, B; Franciosini, M P

    2016-01-01

    Microbiological and parasitological investigation was carried out on a colony of feral pigeons, located in a green area near the main hospital of a Central Italy city. One hundred pigeons were submitted to clinical examination. Cloacal swabs, grouped in pool of 4 samples, were analyzed to detect the presence of Coxiella burnetii, Chlamydia psittaci, Chlamydophila spp. using a biomolecular procedure, while individual cloacal samples were examined for Salmonella spp., Campylobacter spp., and yeasts by means of a specific culture media. An ELISA test was used to determine the presence of Giardia spp., and Cryptosporidium spp. coproantigens. Individual serological samples were also tested with the modified agglutination test (MAT) in order to detect antibodies against Toxoplasma gondii. The pigeons did not show any clinical signs. The cloacal pools proved to be negative for C. burnetii DNA while three pools were positive for C. psittaci or Chlamydophila spp. DNAs. Salmonella spp. was not detected. C. jejuni and C. coli were found in 13% and 4% of the samples, respectively. No Giardia spp. and Cryptosporidium spp. were detected. Thirty-three out of 100 samples (33%) were positive for yeast colonies. The seroprevalence for T. gondii was 8%. Although with moderate incidence, potentially zoonotic agents were present thus highlighting the need for sanitary surveillance on feral pigeon colonies. PMID:27487504

  12. Microbiological and parasitological survey of zoonotic agents in apparently healthy feral pigeons.

    PubMed

    Marenzoni, M L; Morganti, G; Moretta, I; Crotti, S; Agnetti, F; Moretti, A; Pitzurra, L; Casagrande Proietti, P; Sechi, P; Cenci-Goga, B; Franciosini, M P

    2016-01-01

    Microbiological and parasitological investigation was carried out on a colony of feral pigeons, located in a green area near the main hospital of a Central Italy city. One hundred pigeons were submitted to clinical examination. Cloacal swabs, grouped in pool of 4 samples, were analyzed to detect the presence of Coxiella burnetii, Chlamydia psittaci, Chlamydophila spp. using a biomolecular procedure, while individual cloacal samples were examined for Salmonella spp., Campylobacter spp., and yeasts by means of a specific culture media. An ELISA test was used to determine the presence of Giardia spp., and Cryptosporidium spp. coproantigens. Individual serological samples were also tested with the modified agglutination test (MAT) in order to detect antibodies against Toxoplasma gondii. The pigeons did not show any clinical signs. The cloacal pools proved to be negative for C. burnetii DNA while three pools were positive for C. psittaci or Chlamydophila spp. DNAs. Salmonella spp. was not detected. C. jejuni and C. coli were found in 13% and 4% of the samples, respectively. No Giardia spp. and Cryptosporidium spp. were detected. Thirty-three out of 100 samples (33%) were positive for yeast colonies. The seroprevalence for T. gondii was 8%. Although with moderate incidence, potentially zoonotic agents were present thus highlighting the need for sanitary surveillance on feral pigeon colonies.

  13. Molecular detection of Rickettsia, Coxiella and Rickettsiella DNA in three native Australian tick species.

    PubMed

    Vilcins, Inger-Marie E; Old, Julie M; Deane, Elizabeth

    2009-11-01

    Three Australian native animal species yielded 60 samples composed of three indigenous ticks. Hosts included twelve koalas, two echidnas and one wombat from Victoria, and ticks were of the species Ixodes tasmani (n = 42), Bothriocroton concolor (n = 8) and B. auruginans (n = 10), respectively. PCR screening and sequencing detected a species of Coxiella, sharing closest sequence identity to C. burnetii (>98%), in all B. auruginans, as well as a species of Rickettsia, matching closest to R. massiliae, in 70% of the same samples. A genotype sharing closest similarity to Rickettsia bellii (>99%) was identified in three female B. concolor collected from one of the echidnas. Three samples of I. tasmani, taken from three koalas, yielded different genotypes of Rickettsiella. These results represent the first detection of the three genera in each tick species and identify a high level of previously undetected bacterial diversity in Australian ticks. PMID:19296229

  14. Effector Protein Cig2 Decreases Host Tolerance of Infection by Directing Constitutive Fusion of Autophagosomes with the Coxiella-Containing Vacuole

    PubMed Central

    Kohler, Lara J.; Reed, Shawna R.; Sarraf, Shireen A.; Arteaga, David D.

    2016-01-01

    ABSTRACT Coxiella burnetii replicates in an acidified lysosome-derived vacuole. Biogenesis of the Coxiella-containing vacuole (CCV) requires bacterial effector proteins delivered into host cells by the Dot/Icm secretion system. Genetic and cell biological analysis revealed that an effector protein called Cig2 promotes constitutive fusion of autophagosomes with the CCV to maintain this compartment in an autolysosomal stage of maturation. This distinguishes the CCV from other pathogen-containing vacuoles that are targeted by the host autophagy pathway, which typically confers host resistance to infection by delivering the pathogen to a toxic lysosomal environment. By maintaining the CCV in an autolysosomal stage of maturation, Cig2 enabled CCV homotypic fusion and enhanced bacterial virulence in the Galleria mellonella (wax moth) model of infection by a mechanism that decreases host tolerance. Thus, C. burnetii residence in an autolysosomal organelle alters host tolerance of infection, which indicates that Cig2-dependent manipulation of a lysosome-derived vacuole influences the host response to infection. PMID:27435465

  15. Borrelia, Coxiella, and Rickettsia in Carios capensis (Acari: Argasidae) from a brown pelican (Pelecanus occidentalis) rookery in South Carolina, USA.

    PubMed

    Reeves, Will K; Loftis, Amanda D; Sanders, Felicia; Spinks, Mark D; Wills, William; Denison, Amy M; Dasch, Gregory A

    2006-01-01

    Argasid ticks are vectors of viral and bacterial agents of humans and animals. Carios capensis, a tick of seabirds, infests the nests of brown pelicans, Pelecanus occidentalis, and other ground nesting birds along the coast of South Carolina. This tick is associated with pelican nest abandonment and could pose a threat to humans visiting pelican rookeries if visitors are exposed to ticks harboring infectious agents. We collected ticks from a pelican rookery on Deveaux Bank, South Carolina and screened 64 individual ticks, six pools of larvae, and an egg mass for DNA from Bartonella, Borrelia, Coxiella, and Rickettsia by polymerase chain reaction amplification and sequencing. Ticks harbored DNA from "Borrelia lonestari", a novel Coxiella sp., and three species of Rickettsia, including Rickettsia felis and two undescribed Rickettsia spp. DNA from the Coxiella and two undescribed Rickettsia were detected in unfed larvae that emerged in the laboratory, which implies these agents are transmitted vertically by female ticks. We partially characterize the novel Coxiella by molecular means. PMID:16821092

  16. Detection of Microbial Agents in Ticks Collected from Migratory Birds in Central Italy

    PubMed Central

    Toma, Luciano; Mancini, Fabiola; Di Luca, Marco; Cecere, Jacopo G.; Bianchi, Riccardo; Khoury, Cristina; Quarchioni, Elisa; Manzia, Francesca; Rezza, Giovanni

    2014-01-01

    Abstract Tick species characterization and molecular studies were performed within ornithological surveys conducted during 2010 and 2011 in the Lazio Region of central Italy. A total of 137 ticks were collected from 41 migratory birds belonging to 17 species (four partial migrants and 13 long-distance migrants). Most ticks were nymphs, with a predominance of Hyalomma marginatum marginatum and H. m. rufipes, and a small portion of Ixodes and Amblyomma species. All tick species analyzed were infected, and the molecular pathogen recognition revealed the presence of Rickettsia aeschlimannii, Rickettsia africae, Erlichia spp., Coxiella burnetii, Borrelia burgdorferi sensu lato group, and Babesia microti, whereas no genomic DNA of Bartonella spp. or Francisella tularensis was detected. The results of the survey show that H. marginatum ticks appear to be a vector of microbial agents that may affect human and animal health and that migratory birds may be an important carrier of these ticks. Additional studies are needed to better investigate the role of migratory birds in the epidemiology of these pathogens. PMID:24576218

  17. Molecular Survey of Zoonotic Agents in Rodents and Other Small Mammals in Croatia.

    PubMed

    Tadin, Ante; Tokarz, Rafal; Markotić, Alemka; Margaletić, Josip; Turk, Nenad; Habuš, Josipa; Svoboda, Petra; Vucelja, Marko; Desai, Aaloki; Jain, Komal; Lipkin, W Ian

    2016-02-01

    Croatia is a focus for many rodent-borne zoonosis. Here, we report a survey of 242 rodents and small mammals, including 43 Myodes glareolus, 131 Apodemus flavicollis, 53 Apodemus agrarius, three Apodemus sylvaticus, six Sorex araneus, four Microtus arvalis, one Microtus agrestis, and one Muscardinus avellanarius, collected at eight sites in Croatia over an 8-year period. Multiplex MassTag polymerase chain reaction (PCR) was used for detection of Borrelia, Rickettsia, Bartonella, Babesia, Ehrlichia, Anaplasma, Francisella tularensis, and Coxiella burnetii. Individual PCR assays were used for detection of Leptospira, lymphocytic choriomeningitis virus, orthopoxviruses, flaviviruses, hantaviruses, and Toxoplasma gondii. Of the rodents, 52 (21.5%) were infected with Leptospira, 9 (3.7%) with Borrelia miyamotoi, 5 (2%) with Borrelia afzelii, 29 (12.0%) with Bartonella, 8 (3.3%) with Babesia microti, 2 (0.8%) with Ehrlichia, 4 (1.7%) with Anaplasma, 2 (0.8%) with F. tularensis, 43 (17.8%) with hantaviruses, and 1 (0.4%) with an orthopoxvirus. Other agents were not detected. Multiple infections were found in 32 rodents (13.2%): dual infections in 26 rodents (10.7%), triple infections in four rodents (2.9%), and quadruple infections in two rodents (0.8%). Our findings indicate that rodents in Croatia harbor a wide range of bacteria and viruses that are pathogenic to humans.

  18. Development of a set of multiplex standard polymerase chain reaction assays for the identification of infectious agents from aborted bovine clinical samples.

    PubMed

    Tramuta, Clara; Lacerenza, Daniela; Zoppi, Simona; Goria, Mariella; Dondo, Alessandro; Ferroglio, Ezio; Nebbia, Patrizia; Rosati, Sergio

    2011-07-01

    The current study describes the development of a set of 5 multiplex polymerase chain reaction (mPCR) assays for the simultaneous detection of abortive infection agents in bovine fetal tissues, including Brucella spp., Leptospira spp., and Campylobacter fetus (mPCR1); Hammondia heydorni, Neospora caninum, and Toxoplasma gondii (mPCR2); Coxiella burnetii and Chlamydophila psittaci (mPCR3); Mycoplasma bovis, Mycoplasma bovigenitalium, and Ureaplasma diversum (mPCR4); and Bovine viral diarrhea virus (BVDV) and Bovine herpesvirus-1 (BoHV-1; mPCR5). The protocol was tested on different tissue samples collected from 50 aborted bovine fetuses, and it showed that out of the 50 fetuses, 7 (14%, mPCR2) were PCR-positive for N. caninum, 4 (8%, mPCR5) were PCR-positive for BVDV, and 2 (4%, mPCR4) were PCR-positive for U. diversum. The results obtained by using each multiplex PCR were 100% concordant with those obtained by using the respective PCR assays targeting single genes on the same specimens. Moreover, all multiplex PCR assays on clinical samples were compared with reference methods, obtaining a perfect accordance in all samples and confirming the validity of the set of multiplex PCR assays. The proposed set of multiplex PCR assays is, therefore, suitable for the simultaneous detection of the main infectious agents responsible for bovine abortion.

  19. Coxiella burnetii in bulk tank milk samples from dairy goat and dairy sheep farms in The Netherlands in 2008.

    PubMed

    van den Brom, R; van Engelen, E; Luttikholt, S; Moll, L; van Maanen, K; Vellema, P

    2012-03-24

    In 2007, a human Q fever epidemic started, mainly in the south eastern part of The Netherlands with a suspected indirect relation to dairy goats, and, to a lesser degree, to dairy sheep. This article describes the Q fever prevalences in Dutch dairy goat and dairy sheep bulk tank milk (BTM) samples, using a real-time (RT) PCR and ELISA. Results of BTM PCR and ELISA were compared with the serological status of individual animals, and correlations with a history of Q fever abortion were determined. When compared with ELISA results, the optimal cut-off value for the RT-PCR was 100 bacteria/ml. In 2008, there were 392 farms with more than 200 dairy goats, of which 292 submitted a BTM sample. Of these samples, 96 (32.9 per cent) were PCR positive and 87 (29.8 per cent) were ELISA positive. All farms with a history of Q fever abortion (n=17) were ELISA positive, 16 out of 17 were also PCR positive. BTM PCR or ELISA positive farms had significantly higher within-herd seroprevalences than BTM negative farms. In the south eastern provinces, the area where the human Q fever outbreak started in 2007, a significantly larger proportion of the BTM samples was PCR and ELISA positive compared to the rest of The Netherlands. None of the BTM samples from dairy sheep farms (n=16) were PCR positive but three of these farms were ELISA positive. The higher percentage of BTM positive farms in the area where the human Q fever outbreak started, supports the suspected relation between human cases and infected dairy goat farms.

  20. Serologic screening for 13 infectious agents in roe deer (Capreolus capreolus) in Flanders

    PubMed Central

    Tavernier, Paul; Sys, Stanislas U.; De Clercq, Kris; De Leeuw, Ilse; Caij, Anne Brigitte; De Baere, Miet; De Regge, Nick; Fretin, David; Roupie, Virginie; Govaerts, Marc; Heyman, Paul; Vanrompay, Daisy; Yin, Lizi; Kalmar, Isabelle; Suin, Vanessa; Brochier, Bernard; Dobly, Alexandre; De Craeye, Stéphane; Roelandt, Sophie; Goossens, Els; Roels, Stefan

    2015-01-01

    Introduction In order to investigate the role of roe deer in the maintenance and transmission of infectious animal and human diseases in Flanders, we conducted a serologic screening in 12 hunting areas. Materials and methods Roe deer sera collected between 2008 and 2013 (n=190) were examined for antibodies against 13 infectious agents, using indirect enzyme-linked immunosorbent assay, virus neutralisation, immunofluorescence, or microagglutination test, depending on the agent. Results and discussion High numbers of seropositives were found for Anaplasma phagocytophilum (45.8%), Toxoplasma gondii (43.2%) and Schmallenberg virus (27.9%), the latter with a distinct temporal distribution pattern following the outbreak in domestic ruminants. Lower antibody prevalence was found for Chlamydia abortus (6.7%), tick-borne encephalitis virus (5.1%), Neospora caninum (4.8%), and Mycobacterium avium subsp paratuberculosis (4.1%). The lowest prevalences were found for Leptospira (1.7%), bovine viral diarrhoea virus 1 (1.3%), and Coxiella burnetii (1.2%). No antibodies were found against Brucella sp., bovine herpesvirus 1, and bluetongue virus. A significant difference in seroprevalence between ages (higher in adults >1 year) was found for N. caninum. Four doubtful reacting sera accounted for a significant difference in seroprevalence between sexes for C. abortus (higher in females). Conclusions Despite the more intensive landscape use in Flanders, the results are consistent with other European studies. Apart from maintaining C. abortus and MAP, roe deer do not seem to play an important role in the epidemiology of the examined zoonotic and domestic animal pathogens. Nevertheless, their meaning as sentinels should not be neglected in the absence of other wild cervid species. PMID:26609692

  1. Q fever

    MedlinePlus

    ... the bacteria Coxiella burnetii . These bacteria can infect: Sheep Goats Cattle Dogs Cats Birds Rodents Ticks Infected ... Farmers Laboratory workers who work with Coxiella burnetii Sheep and dairy workers Veterinarians People at highest risk ...

  2. Louse-borne bacterial pathogens in lice (Phthiraptera) of rodents and cattle from Egypt.

    PubMed

    Reeves, Will K; Szumlas, Daniel E; Moriarity, John R; Loftis, Amanda D; Abbassy, Magda M; Helmy, Ibrahim M; Dasch, Gregory A

    2006-04-01

    We collected 1,023 lice, representing 5 species, from rats and domestic cattle throughout 13 governorates in Egypt and tested these lice for Anaplasma marginale, Bartonella spp., Brucella spp., Borrelia recurrentis, Coxiella burnetii, Francisella tularensis, and Rickettsia spp. by PCR amplification and sequencing. Five different louse-borne bacterial agents were detected in lice from rodents or cattle, including "Bartonella rattimassiliensis", "B. phoceensis", and Bartonella sp. near Bartonella tribocorum, Coxiella burnetii, and Rickettsia typhi. More lice from governorates bordering the Mediterranean and Red Seas contained pathogens. Our data indicate that lice of urban and domestic animals harbor pathogenic or potentially pathogenic bacterial agents throughout Egypt.

  3. Tissue tropism and vertical transmission of Coxiella in Rhipicephalus sanguineus and Rhipicephalus turanicus ticks.

    PubMed

    Lalzar, Itai; Friedmann, Yael; Gottlieb, Yuval

    2014-12-01

    Arthropod symbionts present tissue tropism that corresponds to the nature of the association and the mode of transmission between host generations. In ticks, however, our knowledge of symbiont tissue tropism and function is limited. Here, we quantified and localized previously described Coxiella-like symbionts in several organs of the tick Rhipicephalus turanicus. Quantitative polymerase chain reaction revealed high densities of Coxiella in the female gonads, and both male and female Malpighian tubules. Using fluorescence in situ hybridization and transmission electron microscopy, we further showed that in the gonads of both Rh. turanicus and Rh. sanguineus, Coxiella does not colonize the primary oocytes but is found later in young and mature oocytes in a specific distribution, suggesting controlled vertical transmission. This method revealed the presence Coxiella in the distal part of the Malpighian tubules, suggesting a possible role in nitrogen metabolism. While testing Rickettsia symbionts, no specific tissue tropism was found, but a slightly higher densities in the tick gut. The low density of Rickettsia in the female ovaries suggests competition between Rickettsia and Coxiella for vertical transmission. The described tissue distribution supports an obligatory role for Coxiella in ticks. PMID:24650112

  4. [Unanticipated outbreak of Q fever during a study using sheep, and its significance for further projects].

    PubMed

    Henning, Klaus; Hotzel, Helmut; Peters, Martin; Welge, Peter; Popps, Walter; Theegarten, Dirk

    2009-01-01

    Effective measures for protection of laboratory staff against infections due to experiments with pathogens are a challenge for safeguarding against hazards. Investigations on limited epidemic infections and their causes are of high relevance. During an experiment with pregnant sheep 5 of 7 persons who took part in the operation procedures developed Q fever 10 to 24 days after exposure. One sheep aborted spontaneously 3 days after the third experiment. Examinations of the aborted material revealed Coxiella burnetii, Chlamydophila psittaci, and Staphylococcus chromogenes. Coxiella burnetii and Chlamydophila psittaci were also detected in some of the other placentae. This outbreak of Q fever during an experiment with infected sheep affected more than 70% of the people involved with this experiment and shows the high risk of working with the zoonotic agent Coxiella burnetii. Hence, technical, organizational, and personnel measures have to be taken, and laboratory animals are to be monitored to prevent further infections. PMID:19226931

  5. Localization and visualization of a coxiella-type symbiont within the lone star tick, Amblyomma americanum.

    PubMed

    Klyachko, Olga; Stein, Barry D; Grindle, Nathan; Clay, Keith; Fuqua, Clay

    2007-10-01

    A Coxiella-type microbe occurs at 100% frequency in all Amblyomma americanum ticks thus far tested. Using laboratory-reared ticks free of other microbes, we identified the Amblyomma-associated Coxiella microbe in several types of tissue and at various stages of the life cycle of A. americanum by 16S rRNA gene sequencing and diagnostic PCR. We visualized Amblyomma-associated Coxiella through the use of a diagnostic fluorescence in situ hybridization (FISH) assay supplemented with PCR-based detection, nucleic acid fluorescent staining, wide-field epifluorescence and confocal microscopy, and transmission electron microscopy (TEM). Specific fluorescent foci were observed in several tick tissues, including the midgut and the Malpighian tubules, but particularly bright signals were observed in the granular acini of salivary gland clusters and in both small and large oocytes. TEM confirmed intracellular bacterial structures in the same tissues. The presence of Amblyomma-associated Coxiella within oocytes is consistent with the vertical transmission of these endosymbionts. Further, the presence of the Amblyomma-associated Coxiella symbiont in other tissues such as salivary glands could potentially lead to interactions with horizontally acquired pathogens. PMID:17720830

  6. Systemic Coxiella-like infection with myocarditis and hepatitis in an eclectus parrot (Eclectus roratus).

    PubMed

    Vapniarsky, N; Barr, B C; Murphy, B

    2012-07-01

    A multiorgan infection with a Coxiella-like organism was determined to be the cause of death of a female eclectus parrot (Eclectus roratus). The diagnosis was based on gross lesions, histopathology, Gimenez and Gram special stains, immunohistochemistry, electron microscopy, and polymerase chain reaction amplification and sequencing of a bacterial 16s rRNA gene fragment isolated from hepatic and cardiac tissue. Gross postmortem examination revealed multifocal to coalescing foci of hepatic necrosis. The most significant histologic lesions included multifocal lymphohistiocytic necrotizing hepatitis, locally extensive lymphoplasmacytic myocarditis, and myocardial degeneration and necrosis. Intralesional cytoplasmic organisms were identified in cardiomyocytes, biliary epithelium, and pancreatic exocrine cells. This is the first description of a Coxiella-like organism with wide-ranging cellular tropisms in a psittacine bird. In addition, lymphoplasmacytic neuritis, myositis, splenitis, airsacculitis, and enteritis were detected. It is also the first report of a Coxiella-like infection in an eclectus parrot.

  7. Localization and Visualization of a Coxiella-Type Symbiont within the Lone Star Tick, Amblyomma americanum▿ †

    PubMed Central

    Klyachko, Olga; Stein, Barry D.; Grindle, Nathan; Clay, Keith; Fuqua, Clay

    2007-01-01

    A Coxiella-type microbe occurs at 100% frequency in all Amblyomma americanum ticks thus far tested. Using laboratory-reared ticks free of other microbes, we identified the Amblyomma-associated Coxiella microbe in several types of tissue and at various stages of the life cycle of A. americanum by 16S rRNA gene sequencing and diagnostic PCR. We visualized Amblyomma-associated Coxiella through the use of a diagnostic fluorescence in situ hybridization (FISH) assay supplemented with PCR-based detection, nucleic acid fluorescent staining, wide-field epifluorescence and confocal microscopy, and transmission electron microscopy (TEM). Specific fluorescent foci were observed in several tick tissues, including the midgut and the Malpighian tubules, but particularly bright signals were observed in the granular acini of salivary gland clusters and in both small and large oocytes. TEM confirmed intracellular bacterial structures in the same tissues. The presence of Amblyomma-associated Coxiella within oocytes is consistent with the vertical transmission of these endosymbionts. Further, the presence of the Amblyomma-associated Coxiella symbiont in other tissues such as salivary glands could potentially lead to interactions with horizontally acquired pathogens. PMID:17720830

  8. [Differential diagnostic and therapeutic aspects of Q-fever in a male prisoner. Case report].

    PubMed

    Vanya, Melinda; Szili, Károly; Zámolyi, Szilvia; Magyar, Hajnalka; Kőrösi, Gábor; Benkő, Árpád; Hornyák, Anna; Hegedűs, Zsolt; György, Lajos

    2015-05-01

    The authors describe the case of a 46-year-old man, who developed atypical pneumonia caused by Coxiella burnetii. Chest X-ray revealed interstitial pneumonia. Western blot and ELISA test were positive for Coxiella burnetii antibody. After treatment with doxycyclin and amoxicillin supplemented with vitamin B6 for 10 days, the patient displayed a clinical improvement. The authors conclude that in cases with atypical pneumonia, Coxiella burnetii antibody as well as other bacterial or viral antibodies should be determined. PMID:26042781

  9. Q Fever Risk in Patients Treated with Chronic Antitumor Necrosis Factor-Alpha Therapy

    PubMed Central

    Astrahan, Anna; Odeh, Majed; Elias, Nizar; Rosner, Itzhak; Rimar, Doron; Kaly, Lisa; Rozenbaum, Michael; Boulman, Nina; Slobodin, Gleb

    2016-01-01

    Q fever is a zoonotic bacterial disease caused by Coxiella burnetii. Tumor necrosis factor-alpha (TNF-α) plays a pivotal role in the defense against infection with this Gram-negative coccobacillus. Theoretically, patients who are treated with anti-TNF-α medications are at risk for developing chronic Q fever. We present two patients who developed Q fever while being treated with anti-TNF-α agents and discuss the significance of timely diagnosis of C. burnetii infection in these patients. PMID:27656302

  10. Q Fever Risk in Patients Treated with Chronic Antitumor Necrosis Factor-Alpha Therapy

    PubMed Central

    Astrahan, Anna; Odeh, Majed; Elias, Nizar; Rosner, Itzhak; Rimar, Doron; Kaly, Lisa; Rozenbaum, Michael; Boulman, Nina; Slobodin, Gleb

    2016-01-01

    Q fever is a zoonotic bacterial disease caused by Coxiella burnetii. Tumor necrosis factor-alpha (TNF-α) plays a pivotal role in the defense against infection with this Gram-negative coccobacillus. Theoretically, patients who are treated with anti-TNF-α medications are at risk for developing chronic Q fever. We present two patients who developed Q fever while being treated with anti-TNF-α agents and discuss the significance of timely diagnosis of C. burnetii infection in these patients.

  11. Distinctive Genome Reduction Rates Revealed by Genomic Analyses of Two Coxiella-Like Endosymbionts in Ticks

    PubMed Central

    Gottlieb, Yuval; Lalzar, Itai; Klasson, Lisa

    2015-01-01

    Genome reduction is a hallmark of symbiotic genomes, and the rate and patterns of gene loss associated with this process have been investigated in several different symbiotic systems. However, in long-term host-associated coevolving symbiont clades, the genome size differences between strains are normally quite small and hence patterns of large-scale genome reduction can only be inferred from distant relatives. Here we present the complete genome of a Coxiella-like symbiont from Rhipicephalus turanicus ticks (CRt), and compare it with other genomes from the genus Coxiella in order to investigate the process of genome reduction in a genus consisting of intracellular host-associated bacteria with variable genome sizes. The 1.7-Mb CRt genome is larger than the genomes of most obligate mutualists but has a very low protein-coding content (48.5%) and an extremely high number of identifiable pseudogenes, indicating that it is currently undergoing genome reduction. Analysis of encoded functions suggests that CRt is an obligate tick mutualist, as indicated by the possible provisioning of the tick with biotin (B7), riboflavin (B2) and other cofactors, and by the loss of most genes involved in host cell interactions, such as secretion systems. Comparative analyses between CRt and the 2.5 times smaller genome of Coxiella from the lone star tick Amblyomma americanum (CLEAA) show that many of the same gene functions are lost and suggest that the large size difference might be due to a higher rate of genome evolution in CLEAA generated by the loss of the mismatch repair genes mutSL. Finally, sequence polymorphisms in the CRt population sampled from field collected ticks reveal up to one distinct strain variant per tick, and analyses of mutational patterns within the population suggest that selection might be acting on synonymous sites. The CRt genome is an extreme example of a symbiont genome caught in the act of genome reduction, and the comparison between CLEAA and CRt

  12. Distinctive Genome Reduction Rates Revealed by Genomic Analyses of Two Coxiella-Like Endosymbionts in Ticks.

    PubMed

    Gottlieb, Yuval; Lalzar, Itai; Klasson, Lisa

    2015-06-01

    Genome reduction is a hallmark of symbiotic genomes, and the rate and patterns of gene loss associated with this process have been investigated in several different symbiotic systems. However, in long-term host-associated coevolving symbiont clades, the genome size differences between strains are normally quite small and hence patterns of large-scale genome reduction can only be inferred from distant relatives. Here we present the complete genome of a Coxiella-like symbiont from Rhipicephalus turanicus ticks (CRt), and compare it with other genomes from the genus Coxiella in order to investigate the process of genome reduction in a genus consisting of intracellular host-associated bacteria with variable genome sizes. The 1.7-Mb CRt genome is larger than the genomes of most obligate mutualists but has a very low protein-coding content (48.5%) and an extremely high number of identifiable pseudogenes, indicating that it is currently undergoing genome reduction. Analysis of encoded functions suggests that CRt is an obligate tick mutualist, as indicated by the possible provisioning of the tick with biotin (B7), riboflavin (B2) and other cofactors, and by the loss of most genes involved in host cell interactions, such as secretion systems. Comparative analyses between CRt and the 2.5 times smaller genome of Coxiella from the lone star tick Amblyomma americanum (CLEAA) show that many of the same gene functions are lost and suggest that the large size difference might be due to a higher rate of genome evolution in CLEAA generated by the loss of the mismatch repair genes mutSL. Finally, sequence polymorphisms in the CRt population sampled from field collected ticks reveal up to one distinct strain variant per tick, and analyses of mutational patterns within the population suggest that selection might be acting on synonymous sites. The CRt genome is an extreme example of a symbiont genome caught in the act of genome reduction, and the comparison between CLEAA and CRt

  13. Vaccination against Q fever for biodefense and public health indications

    PubMed Central

    Ruiz, Sara; Wolfe, Daniel N.

    2014-01-01

    Coxiella burnetii is the etiological agent of Q fever, a disease that is often spread to humans via inhalational exposure to the bacteria from contaminated agricultural sources. Outbreaks have been observed all over the world with larger foci generating interest in vaccination programs, most notably in Australia and the Netherlands. Importantly, exposure rates among military personnel deployed to the Middle East can be relatively high as measured by seroconversion to C. burnetii-specific antibodies. Q fever has been of interest to the biodefense community over the years due to its low infectious dose and environmental stability. Recent advances in cell-free growth and genetics of C. burnetii also make this organism easier to culture and manipulate. While there is a vaccine that is licensed for use in Australia, the combination of biodefense- and public health-related issues associated with Q fever warrant the development of a safer and more effective vaccine against this disease. PMID:25566235

  14. Novel Detection of Coxiella spp., Theileria luwenshuni, and T. ovis Endosymbionts in Deer Keds (Lipoptena fortisetosa).

    PubMed

    Lee, Seung-Hun; Kim, Kyoo-Tae; Kwon, Oh-Deog; Ock, Younsung; Kim, Taeil; Choi, Donghag; Kwak, Dongmi

    2016-01-01

    We describe for the first time the detection of Coxiella-like bacteria (CLB), Theileria luwenshuni, and T. ovis endosymbionts in blood-sucking deer keds. Eight deer keds attached to a Korean water deer were identified as Lipoptena fortisetosa (Diptera: Hippoboscidae) by morphological and genetic analyses. Among the endosymbionts assessed, CLB, Theileria luwenshuni, and T. ovis were identified in L. fortisetosa by PCR and nucleotide sequencing. Based on phylogeny, CLB 16S rRNA sequences were classified into clade B, sharing 99.4% identity with CLB from Haemaphysalis longicornis in South Korea. Although the virulence of CLB to vertebrates is still controversial, several studies have reported clinical symptoms in birds due to CLB infections. The 18S rRNA sequences of T. luwenshuni and T. ovis in this study were 98.8-100% identical to those in GenBank, and all of the obtained sequences of T. ovis and T. luwenshuni in this study were 100% identical to each other, respectively. Although further studies are required to positively confirm L. fortisetosa as a biological vector of these pathogens, strong genetic relationships among sequences from this and previous studies suggest potential transmission among mammalian hosts by ticks and keds. PMID:27244561

  15. Novel Detection of Coxiella spp., Theileria luwenshuni, and T. ovis Endosymbionts in Deer Keds (Lipoptena fortisetosa)

    PubMed Central

    Lee, Seung-Hun; Kim, Kyoo-Tae; Kwon, Oh-Deog; Ock, Younsung; Kim, Taeil; Choi, Donghag

    2016-01-01

    We describe for the first time the detection of Coxiella-like bacteria (CLB), Theileria luwenshuni, and T. ovis endosymbionts in blood-sucking deer keds. Eight deer keds attached to a Korean water deer were identified as Lipoptena fortisetosa (Diptera: Hippoboscidae) by morphological and genetic analyses. Among the endosymbionts assessed, CLB, Theileria luwenshuni, and T. ovis were identified in L. fortisetosa by PCR and nucleotide sequencing. Based on phylogeny, CLB 16S rRNA sequences were classified into clade B, sharing 99.4% identity with CLB from Haemaphysalis longicornis in South Korea. Although the virulence of CLB to vertebrates is still controversial, several studies have reported clinical symptoms in birds due to CLB infections. The 18S rRNA sequences of T. luwenshuni and T. ovis in this study were 98.8–100% identical to those in GenBank, and all of the obtained sequences of T. ovis and T. luwenshuni in this study were 100% identical to each other, respectively. Although further studies are required to positively confirm L. fortisetosa as a biological vector of these pathogens, strong genetic relationships among sequences from this and previous studies suggest potential transmission among mammalian hosts by ticks and keds. PMID:27244561

  16. Molecular Evidence for a Novel Coxiella from Argas monolakensis (Acari: Argasidae) from Mono Lake, California, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Argasid ticks are vectors of viral and bacterial agents of humans and animals. Recent reports indicate that some ornithophilic argasids harbored rickettsial agents. A Nearctic tick, Argas monolakensis Schwan, Corwin, Brown is ornithophilic and has not previously been examined for rickettsial agents....

  17. Seroprevalence of seven zoonotic pathogens in pregnant women from the Caribbean.

    PubMed

    Wood, Heidi; Drebot, Michael A; Dewailly, Eric; Dillon, Liz; Dimitrova, Kristina; Forde, Martin; Grolla, Allen; Lee, Elise; Loftis, Amanda; Makowski, Kai; Morrison, Karen; Robertson, Lyndon; Krecek, Rosina C

    2014-09-01

    Studies examining the prevalence of zoonotic agents in the Caribbean are very limited. The objective of this study was to examine the seroprevalence of seven zoonotic agents among individuals residing on 10 English-speaking Caribbean countries. Sera from healthy, pregnant women were collected from Antigua-Barbuda, Belize, Bermuda, Dominica, Grenada, Jamaica, Montserrat, St. Kitts-Nevis, St. Lucia, and St. Vincent-Grenadines and tested for the presence of IgG antibodies to dengue virus, hepatitis E virus, hantaviruses, leptospiral agents, spotted fever group rickettsiae (SFGR), typhus group rickettsiae (TGR), and Coxiella burnetii (Q fever). The highest seroprevalence values were observed for dengue virus, SFGR, and leptospirosis, although the lowest seroprevalence values were observed for hepatitis E virus, C. burnetii, and TGR. Antibodies to hantaviruses were not detected in any individuals.

  18. Rickettsial pathogens in the tropical rat mite Ornithonyssus bacoti (Acari: Macronyssidae) from Egyptian rats (Rattus spp.).

    PubMed

    Reeves, Will K; Loftis, Amanda D; Szumlas, Daniel E; Abbassy, Magda M; Helmy, Ibrahim M; Hanafi, Hanafi A; Dasch, Gregory A

    2007-01-01

    We collected and tested 616 tropical rat mites (Ornithonyssus bacoti (Hirst)) from rats (Rattus norvegicus (Berkenhout) and R. rattus (Linnaeus)) throughout 14 governorates in Egypt and tested DNA extracts from pools of these mites for Bartonella spp., Coxiella burnetii, and Rickettsia spp. by PCR amplification and sequencing. Three different mite-associated bacterial agents, including one Bartonella and two Rickettsia spp., were detected in eight pools of mites. Further research could demonstrate the vector potential of mites and pathogenicity of these agents to humans or animals. PMID:17225079

  19. Agent Orange

    MedlinePlus

    ... Index Agent Orange Agent Orange Home Facts about Herbicides Veterans' Diseases Birth Defects Benefits Exposure Locations Provider ... millions of gallons of Agent Orange and other herbicides on trees and vegetation during the Vietnam War. ...

  20. Survival of Mycobacterium avium and Mycobacterium tuberculosis in Acidified Vacuoles of Murine Macrophages

    PubMed Central

    Gomes, Maria Salomé; Paul, Simon; Moreira, Andre L.; Appelberg, Rui; Rabinovitch, Michel; Kaplan, Gilla

    1999-01-01

    Despite the antimicrobial mechanisms of vertebrate phagocytes, mycobacteria can survive within the phagosomes of these cells. These organisms use various strategies to evade destruction, including inhibition of acidification of the phagosome and inhibition of phagosome-lysosome fusion. In contrast to mycobacteria, Coxiella burnetii, the etiologic agent of Q fever, inhabits a spacious acidified intracellular vacuole which is prone to fusion with other vacuoles of the host cell, including phagosomes containing mycobacteria. The Coxiella-infected cell thus provides a unique model for investigating the survival of mycobacteria in an acidified phagosome-like compartment. In the present study, murine bone marrow-derived macrophages were infected with either Mycobacterium avium or Mycobacterium tuberculosis and then coinfected with C. burnetii. We observed that the majority of phagocytosed mycobacteria colocalized to the C. burnetii-containing vacuole, which maintained its acidic properties. In coinfected macrophages, the growth of M. avium was not impaired following fusion with the acidified vacuole. In contrast, the growth rate of M. tuberculosis was reduced in acidified vacuoles. These results suggest that although both species of mycobacteria inhibit phagosome-lysosome fusion, they may be differentially susceptible to the toxic effects of the acidic environment in the mature phagolysosome. PMID:10377091

  1. Q Fever: Statistics and Epidemiology

    MedlinePlus

    ... infection with the obligate, intracellular bacterium, Coxiella burnetii . Cattle, sheep, and goats are commonly infected and may ... and plains states where ranching and rearing of cattle are common. In other states, areas where sheep, ...

  2. Antibody prevalence of eight ruminant infectious diseases in California mule and black-tailed deer (Odocoileus hemionus).

    PubMed

    Chomel, B B; Carniciu, M L; Kasten, R W; Castelli, P M; Work, T M; Jessup, D A

    1994-01-01

    We tested 276 sera from 18 free-ranging black-tailed and mule deer (Odocoileus hemionus) herds in California (USA) collected from 1987 to 1991 in five biogeographical habitat types, for antibodies against eight infectious disease agents. Overall antibody prevalence was 56% for Anaplasma marginale, 31% for Borrelia burgdorferi, 16% for bluetongue virus serotype 17, 15% for epizootic hemorrhagic disease virus, 7% for Coxiella burnetii and Toxoplasma gondii, respectively, and 0% for bovine leukosis virus and caprine arthritis/encephalitis virus, respectively. Antibodies against Lyme borreliosis and anaplasmosis were found in deer throughout California, but antibodies against bluetongue and epizootic hemorrhagic disease were most prevalent in deer from southern California.

  3. Biological Agents

    MedlinePlus

    ... to Z Index Contact Us FAQs What's New Biological Agents This page requires that javascript be enabled ... and Health Topics A-Z Index What's New Biological agents include bacteria, viruses, fungi, other microorganisms and ...

  4. Surgical and Antimicrobial Management of a Thoracic Aortic Aneurysm Due to Q Fever: A Case Report and Brief Review.

    PubMed

    Robinson, William P; Schuksz, Manuela

    2016-05-01

    Coxiella burnetii, the etiologic agent of Q fever, has been associated with vascular infection and aneurysm formation. We report the case of a 36-year-old woman from Iraq who presented with long-standing malaise as well as vague chest and shoulder discomfort and was found to have a saccular aneurysm of the descending thoracic aorta. Serology assays were positive for chronic C burnetii infection. She was treated with successful aneurysm resection and aortic replacement with a rifampin-impregnated Maquet Hemashield (TM) Dacron interposition graft interposition graft in addition to 18 months of doxycycline and hydroxychloroquine. The patient is without evidence of recurrent infection on follow-up at 3 years. To our knowledge, this is the first case of aortic aneurysm secondary to Q fever reported in the United States. We review the diagnosis, surgical management, antibiotic therapy, and surveillance of a thoracic aortic aneurysm secondary to Q fever. PMID:27075992

  5. Q fever in French Guiana.

    PubMed

    Eldin, Carole; Mahamat, Aba; Demar, Magalie; Abboud, Philippe; Djossou, Félix; Raoult, Didier

    2014-10-01

    Coxiella burnetii, the causative agent of Q fever, is present worldwide. Recent studies have shown that this bacterium is an emerging pathogen in French Guiana and has a high prevalence (24% of community-acquired pneumonia). In this review, we focus on the peculiar epidemiology of Q fever in French Guiana. We place it in the context of the epidemiology of the disease in the surrounding countries of South America. We also review the clinical features of Q fever in this region, which has severe initial presentation but low mortality rates. These characteristics seem to be linked to a unique genotype (genotype 17). Finally, we discuss the issue of the animal reservoir of C. burnetii in French Guiana, which is still unknown. Further studies are necessary to identify this reservoir. Identification of this reservoir will improve the understanding of the Q fever epidemic in French Guiana and will provide new tools to control this public health problem.

  6. Rickettsial diseases and ectoparasites from military bases in Japan.

    PubMed

    Reeves, Will K; Durden, Lance A; Iwakami, Masahiro; Vince, Kent J; Paul, Robert R

    2015-04-01

    Ectoparasitic arthropods are often vectors of rickettsiosis. We conducted a survey of ectoparasites on U.S. military facilities throughout Japan with the use of specimens submitted by pest control, public health, and veterinary personnel. Over 1,600 individual ectoparasites were collected. Fifteen species were identified, including several significant vectors of human diseases such as scrub typhus and rickettsial spotted fevers. These ectoparasites included Ctenocephalides felis , Haemaphysalis longicornis, Ixodes persulcatus , Leptotrombidium fuji, Leptotrombidium pallidum, and Rhipicephalus sanguineus . Rickettsial agents were detected by PCR and DNA sequencing. These included Bartonella henselae , Bartonella japonica, a novel Bartonella, Coxiella burnetii , an unnamed Coxiella, Ehrlichia canis , Orientia tsutsugamushi , Rickettsia typhi , and "Rickettsia Rf2125"/"Rickettsia cf1and5".

  7. Seroconversions for Coxiella and Rickettsial Pathogens among US Marines Deployed to Afghanistan, 2001–2010

    PubMed Central

    Pho, Nhien; Myers, Todd E.; Richards, Allen L.

    2016-01-01

    We assessed serum samples from 1,000 US Marines deployed to Afghanistan during 2001–2010 to find evidence of 4 rickettsial pathogens. Analysis of predeployment and postdeployment samples showed that 3.4% and 0.5% of the Marines seroconverted for the causative agents of Q fever and spotted fever group rickettsiosis, respectively. PMID:27434653

  8. Seroconversions for Coxiella and Rickettsial Pathogens among US Marines Deployed to Afghanistan, 2001-2010.

    PubMed

    Farris, Christina M; Pho, Nhien; Myers, Todd E; Richards, Allen L

    2016-08-01

    We assessed serum samples from 1,000 US Marines deployed to Afghanistan during 2001-2010 to find evidence of 4 rickettsial pathogens. Analysis of predeployment and postdeployment samples showed that 3.4% and 0.5% of the Marines seroconverted for the causative agents of Q fever and spotted fever group rickettsiosis, respectively. PMID:27434653

  9. Survey of infectious etiologies of bovine abortion during mid- to late gestation in dairy herds.

    PubMed

    Barkallah, Mohamed; Gharbi, Yaakoub; Hassena, Amal Ben; Slima, Ahlem Ben; Mallek, Zouhir; Gautier, Michel; Greub, Gilbert; Gdoura, Radhouane; Fendri, Imen

    2014-01-01

    Bovine abortion of unknown infectious etiology still remains a major economic problem. Thus, we investigated whether Brucella spp., Listeria monocytogenes, Salmonella spp., Campylobacter spp. and Coxiella burnetii are associated with abortion and/or stillbirth in Tunisian dairy cattle. Using a pan-Chlamydiales PCR, we also investigated the role of Chlamydiaceae, Waddlia chondrophila, Parachlamydia acanthamoebae and other members of the Chlamydiales order in this setting. Veterinary samples taken from mid to late-term abortions from twenty dairy herds were tested. From a total of 150 abortion cases collected, infectious agents were detected by PCR in 73 (48.66%) cases, 13 (8.66%) of which represented co-infections with two infectious agents. Detected pathogens include Brucella spp (31.3%), Chlamydiaceae (4.66%), Waddlia chondrophila (8%), Parachlamydia acanthamoebae (5.33%), Listeria monocytogenes (4.66%) and Salmonella spp. (3.33%). In contrast, Campylobacter spp. and Coxiella burnetii DNA were not detected among the investigated veterinary samples. This demonstrates that different bacterial agents may cause bovine abortion in Tunisia. This is the first report suggesting the role of Parachlamydia acanthamoebae in bovine abortion in Africa. Further studies with a larger number of samples are necessary to confirm whether this emerging pathogen is directly linked to abortion in cattle.

  10. Survey of Infectious Etiologies of Bovine Abortion during Mid- to Late Gestation in Dairy Herds

    PubMed Central

    Barkallah, Mohamed; Slima, Ahlem Ben; Mallek, Zouhir; Gautier, Michel; Greub, Gilbert; Gdoura, Radhouane; Fendri, Imen

    2014-01-01

    Bovine abortion of unknown infectious etiology still remains a major economic problem. Thus, we investigated whether Brucella spp., Listeria monocytogenes, Salmonella spp., Campylobacter spp. and Coxiella burnetii are associated with abortion and/or stillbirth in Tunisian dairy cattle. Using a pan-Chlamydiales PCR, we also investigated the role of Chlamydiaceae, Waddlia chondrophila, Parachlamydia acanthamoebae and other members of the Chlamydiales order in this setting. Veterinary samples taken from mid to late-term abortions from twenty dairy herds were tested. From a total of 150 abortion cases collected, infectious agents were detected by PCR in 73 (48.66%) cases, 13 (8.66%) of which represented co-infections with two infectious agents. Detected pathogens include Brucella spp (31.3%), Chlamydiaceae (4.66%), Waddlia chondrophila (8%), Parachlamydia acanthamoebae (5.33%), Listeria monocytogenes (4.66%) and Salmonella spp. (3.33%). In contrast, Campylobacter spp. and Coxiella burnetii DNA were not detected among the investigated veterinary samples. This demonstrates that different bacterial agents may cause bovine abortion in Tunisia. This is the first report suggesting the role of Parachlamydia acanthamoebae in bovine abortion in Africa. Further studies with a larger number of samples are necessary to confirm whether this emerging pathogen is directly linked to abortion in cattle. PMID:24662769

  11. Sunscreening Agents

    PubMed Central

    Martis, Jacintha; Shobha, V; Sham Shinde, Rutuja; Bangera, Sudhakar; Krishnankutty, Binny; Bellary, Shantala; Varughese, Sunoj; Rao, Prabhakar; Naveen Kumar, B.R.

    2013-01-01

    The increasing incidence of skin cancers and photodamaging effects caused by ultraviolet radiation has increased the use of sunscreening agents, which have shown beneficial effects in reducing the symptoms and reoccurrence of these problems. Many sunscreen compounds are in use, but their safety and efficacy are still in question. Efficacy is measured through indices, such as sun protection factor, persistent pigment darkening protection factor, and COLIPA guidelines. The United States Food and Drug Administration and European Union have incorporated changes in their guidelines to help consumers select products based on their sun protection factor and protection against ultraviolet radiation, whereas the Indian regulatory agency has not yet issued any special guidance on sunscreening agents, as they are classified under cosmetics. In this article, the authors discuss the pharmacological actions of sunscreening agents as well as the available formulations, their benefits, possible health hazards, safety, challenges, and proper application technique. New technologies and scope for the development of sunscreening agents are also discussed as well as the role of the physician in patient education about the use of these agents. PMID:23320122

  12. Antiparasitic agents.

    PubMed

    Rosenblatt, J E

    1992-03-01

    In recent years, introduction of new and more effective agents has improved the overall therapy for parasitic infections. This field, however, is still plagued by numerous problems, including the development of resistance to antimicrobial agents (especially with malaria), unavailability of agents in the United States or lack of approval by the Food and Drug Administration, and major toxicities or lack of experience in pregnant women and children, which limits use in these groups of patients. Widespread resistance of Plasmodium falciparum to chloroquine and other agents has complicated the treatment and prophylaxis of this type of malaria. A combination of quinine and Fansidar is usually effective oral therapy for falciparum malaria; quinidine may be administered if intravenous therapy is needed. Mefloquine, which is currently recommended for prophylaxis against chloroquine-resistant P. falciparum, is also effective for single-dose oral treatment, although this regimen has not yet been approved by the Food and Drug Administration. Metronidazole has been widely used for treatment of gastroenteritis due to Entamoeba histolytica and Giardia lamblia (not approved by the Food and Drug Administration for the latter) and is considered safe and effective. A new macrolide, azithromycin, has been reported to be effective for cryptosporidiosis in experimental animals; currently, no effective therapy is available for human infections. Combinations of sulfonamides with other antifolates, trimethoprim or pyrimethamine, are recommended therapy for Pneumocystis carinii pneumonia or toxoplasmosis, respectively. Therapies for the various types of leishmaniasis and trypanosomiasis are complex, often toxic, and often of limited efficacy. The benzimidazoles are effective for roundworm infections, although thiabendazole has severe toxic effects. The recent introduction of ivermectin has revolutionized the treatment and control of onchocerciasis. Another relatively new agent, praziquantel

  13. Antidiabetic Agents.

    ERIC Educational Resources Information Center

    Plummer, Nancy; Michael, Nancy, Ed.

    This module on antidiabetic agents is intended for use in inservice or continuing education programs for persons who administer medications in long-term care facilities. Instructor information, including teaching suggestions, and a listing of recommended audiovisual materials and their sources appear first. The module goal and objectives are then…

  14. First serologic survey of Q fever in free-range yaks in China.

    PubMed

    Yin, M Y; Tan, Q D; Qin, S Y; Hu, L Y; Liu, G H; Zhou, D H; Zhu, X Q

    2015-01-01

    The objective of the present investigation was to determine the seroprevalence of Coxiella burnetii infection in free-range yaks in China. A total of 552 serum samples were collected from yaks in Gansu province, northwest China between April 2013 and January 2014, and antibodies against C. burnetii were evaluated using enzyme-linked immunosorbent assay (ELISA). Overall, 13.59% (75/552, 95% CI: 10.73-16.45) of the examined animals were positive for C. burnetii antibodies. There was no significant difference in C. burnetii seroprevalence between female yaks (13.78%, 95% CI: 10.36-17.19) and male yaks (13.13%, 95% CI: 7.89-18.36) (P>0.05). Coxiella burnetii seroprevalence in yaks in different age groups ranged from 10.88% to 15.26%, but the difference was not statistically significant (P>0.05). Coxiella burnetii seroprevalence in yaks sampled in different seasons ranged from 12.06% (autumn) to 18.33% (summer), but the difference was not statistically significant (P>0.05). This is the first report of C. burnetii seroprevalence in free-range yaks in China, indicating the need for measures to be taken to control C. burnetii infection in free-range yaks in China. PMID:27175178

  15. A case of person-to-person transmission of Q fever from an active duty serviceman to his spouse.

    PubMed

    Miceli, Marisa H; Veryser, Andrea Kay; Anderson, Alicia D; Hofinger, Diedre; Lee, Samuel A; Tancik, Corey

    2010-06-01

    Coxiella burnetii has recently gained military relevance given its potential as a bioterrorism agent, and the multiple cases reported among U.S. military personnel deployed to the Middle East. Sexual transmission of Q fever is rare but has been reported in the literature. We describe the possible sexual transmission of Q fever from a returning serviceman from Iraq to his wife. In a recent editorial commentary, Dr. Raoult wrote about the reemergence of Q fever after September 11, 2001 (Raoult 2009). Indeed, C. burnetii has gained military relevance given its potential as a bioterrorism agent and the multiple cases reported among military personnel deployed in Southwest/Central Asia and North Africa (Botros et al. 1995 , Meskini et al. 1995 , Leung-Shea and Danaher 2006 ). Human serosurveys in these geographic areas have reported prevalence rates for Q fever ranging from 10% to 37% in contrast to the United States, which has an estimated Q fever seroprevalence of 3.1% (Botros et al. 1995, Meskini et al. 1995, Anderson et al. 2009). There is no data available for Q fever seroprevalence in Iraq. As a consequence, native populations in these regions may be more likely to possess immunity, and newcomers, such as U.S. military personnel, would be vulnerable to acute infection (Derrick 1973). We report on the possible sexual transmission of C. burnetii from a serviceman in the late recovery of acute Q fever to his wife.

  16. KGB agents

    NASA Astrophysics Data System (ADS)

    Gaina, Alex

    A short story is reported in which the activity of Communist Party of the USSR and secret KGB agents, which were payed by the State, in view of controlling of the conscience of population. The story reffers to the Physics Department of the Moscow University, Planing Institute of the Gosplan of Moldavian S.S.R. and Chishinau Technical University (actually: Technical University of Moldova), where the author has worked during Soviet times. Almost every 6-th citizen in the USSR was engaged in this activity, while actually the former communists rule in the Republic of Moldova.

  17. Filling agents.

    PubMed

    Glavas, Ioannis P

    2005-06-01

    Injectable fillers have become an important component of minimally invasive facial rejuvenation modalities. Their ease of use, effectiveness, low morbidity, and fast results with minimal downtime are factors that have made them popular among patients. Soft tissue augmentation has evolved to a unique combination of medicine and art. A wide selection of available agents and new products, each one with unique properties, may be used alone or in combination. The physician acquires the tools to rebalance facial characteristics not only by filling wrinkles but also by having the ability to shape the face and restore bony contours and lines. Careful selection of candidates, realistic expectations, and an understanding of the limitations of fillers are crucial for a successful result.

  18. Spread of ticks and tick-borne diseases in Germany due to global warming.

    PubMed

    Hartelt, Kathrin; Pluta, Silvia; Oehme, Rainer; Kimmig, Peter

    2008-12-01

    Tick-transmitted diseases like tick-borne encephalitis and Lyme Borreliosis have been well known in Germany for decades. Global climate changes may influence the emergence and reemergence of diseases. Ongoing research now gives an additional focus on other tick-borne pathogens such as Coxiella burnetii, Rickettsia conorii, Anaplasma phagocytophilum and Babesia spp., the causative agents of Q-fever, Mediterranean spotted fever, Anaplasmosis and Babesiosis, respectively. The epidemiology of these pathogens was investigated on ticks as well as on rodents, the main hosts. Therefore adults of Dermacentor spp. (n = 862) and rodents (n = 119) were collected and examined for the existence of C. burnetii and Rickettsia spp. by polymerase chain reaction (PCR). In none of the ticks and rodents C. burnetii could be detected, in contrast to Rickettsia spp. where the infection rate in ticks was about 20%. Over and above that, nymphs and adults of Ixodes ricinus were also collected and investigated by PCR for A. phagocytophilum (n = 5,424), Rickettsia helvetica (n = 1,187) and Babesia spp. (n = 3,113). Thereby infection rates of 1%, 8.9% and 1%, respectively, could be determined. The prevalence in rodents was 5.3% for A. phagocytophilum and 0.8% for Babesia microti. None of the rodents was R. helvetica positive.

  19. Health care agents

    MedlinePlus

    Durable power of attorney for health care; Health care proxy; End-of-life - health care agent; Life support treatment - ... Respirator - health care agent; Ventilator - health care agent; Power of attorney - health care agent; POA - health care ...

  20. Detecting agents.

    PubMed Central

    Johnson, Susan C

    2003-01-01

    This paper reviews a recent set of behavioural studies that examine the scope and nature of the representational system underlying theory-of-mind development. Studies with typically developing infants, adults and children with autism all converge on the claim that there is a specialized input system that uses not only morphological cues, but also behavioural cues to categorize novel objects as agents. Evidence is reviewed in which 12- to 15-month-old infants treat certain non-human objects as if they have perceptual/attentional abilities, communicative abilities and goal-directed behaviour. They will follow the attentional orientation of an amorphously shaped novel object if it interacts contingently with them or with another person. They also seem to use a novel object's environmentally directed behaviour to determine its perceptual/attentional orientation and object-oriented goals. Results from adults and children with autism are strikingly similar, despite adults' contradictory beliefs about the objects in question and the failure of children with autism to ultimately develop more advanced theory-of-mind reasoning. The implications for a general theory-of-mind development are discussed. PMID:12689380

  1. Novel Ehrlichia and Hepatozoon agents infecting the crab-eating fox (Cerdocyon thous) in southeastern Brazil.

    PubMed

    Almeida, Aliny P; Souza, Tayse D; Marcili, Arlei; Labruna, Marcelo B

    2013-05-01

    This study evaluated infection by vector-borne agents in 58 crab-eating fox (Cerdocyon thous L.) that were road-killed in an Atlantic rainforest reserve in the state of Espírito Santo, southeastern Brazil. Spleen, lung, or blood samples collected from the foxes were tested in the laboratory by a battery of polymerase chain reaction (PCR) assays targeting bacteria of the genera Rickettsia, Borrelia, Coxiella, Anaplasma, and Ehrlichia; and protozoa of the genera Babesia, Hepatozoon, and Leishmania. Of the targeted organisms, evidence of infection in the foxes was detected for Ehrlichia and Hepatozoon organisms only. Overall, six (10.3%) foxes were infected by an ehrlichial agent closely related to an ehrlichial agent recently detected in free-ranging Jaguars [(Panthera onca (L.)] in central-western Brazil, and to Ehrlichia ruminantium. For Hepatozoon, 28 (48.3%) foxes were infected by an agent closely related to Hepatozoon sp. Curupira 2 and H. americanum; and one (1.7%) fox was infected by an organism closely related to reptile-associated Hepatozoon agents. Finally, 11 (19.0%) foxes were found infested by Amblyomma cajennense (F.) nymphs, which were all PCR negative for the range of vector-borne agents cited above. Because the haplotypes found in free-ranging foxes are genetically closely related to pathogens of great veterinary importance, namely E. ruminantium and H. americanum, it is highly desirable to know if these novel organisms have any important role as agents of diseases in domestic animals and wildlife in Brazil. PMID:23802461

  2. Novel Ehrlichia and Hepatozoon agents infecting the crab-eating fox (Cerdocyon thous) in southeastern Brazil.

    PubMed

    Almeida, Aliny P; Souza, Tayse D; Marcili, Arlei; Labruna, Marcelo B

    2013-05-01

    This study evaluated infection by vector-borne agents in 58 crab-eating fox (Cerdocyon thous L.) that were road-killed in an Atlantic rainforest reserve in the state of Espírito Santo, southeastern Brazil. Spleen, lung, or blood samples collected from the foxes were tested in the laboratory by a battery of polymerase chain reaction (PCR) assays targeting bacteria of the genera Rickettsia, Borrelia, Coxiella, Anaplasma, and Ehrlichia; and protozoa of the genera Babesia, Hepatozoon, and Leishmania. Of the targeted organisms, evidence of infection in the foxes was detected for Ehrlichia and Hepatozoon organisms only. Overall, six (10.3%) foxes were infected by an ehrlichial agent closely related to an ehrlichial agent recently detected in free-ranging Jaguars [(Panthera onca (L.)] in central-western Brazil, and to Ehrlichia ruminantium. For Hepatozoon, 28 (48.3%) foxes were infected by an agent closely related to Hepatozoon sp. Curupira 2 and H. americanum; and one (1.7%) fox was infected by an organism closely related to reptile-associated Hepatozoon agents. Finally, 11 (19.0%) foxes were found infested by Amblyomma cajennense (F.) nymphs, which were all PCR negative for the range of vector-borne agents cited above. Because the haplotypes found in free-ranging foxes are genetically closely related to pathogens of great veterinary importance, namely E. ruminantium and H. americanum, it is highly desirable to know if these novel organisms have any important role as agents of diseases in domestic animals and wildlife in Brazil.

  3. Preparing Change Agents for Change Agent Roles.

    ERIC Educational Resources Information Center

    Sedlacek, James R.

    Seventy-seven Spanish- and Portuguese-speaking agricultural change agents from developing Central and South American countries responded to a questionnaire which sought perceptions of the roles in which the change agents felt they were involved and the roles for which they felt they were being trained. The agents were participating in training…

  4. Remote Agent Demonstration

    NASA Technical Reports Server (NTRS)

    Dorais, Gregory A.; Kurien, James; Rajan, Kanna

    1999-01-01

    We describe the computer demonstration of the Remote Agent Experiment (RAX). The Remote Agent is a high-level, model-based, autonomous control agent being validated on the NASA Deep Space 1 spacecraft.

  5. Potential animal and environmental sources of Q fever infection for humans in Queensland.

    PubMed

    Tozer, S J; Lambert, S B; Strong, C L; Field, H E; Sloots, T P; Nissen, M D

    2014-03-01

    Q fever is a vaccine-preventable disease; despite this, high annual notification numbers are still recorded in Australia. We have previously shown seroprevalence in Queensland metropolitan regions is approaching that of rural areas. This study investigated the presence of nucleic acid from Coxiella burnetii, the agent responsible for Q fever, in a number of animal and environmental samples collected throughout Queensland, to identify potential sources of human infection. Samples were collected from 129 geographical locations and included urine, faeces and whole blood from 22 different animal species; 45 ticks were removed from two species, canines and possums; 151 soil samples; 72 atmospheric dust samples collected from two locations and 50 dust swabs collected from domestic vacuum cleaners. PCR testing was performed targeting the IS1111 and COM1 genes for the specific detection of C. burnetii DNA. There were 85 detections from 1318 animal samples, giving a detection rate for each sample type ranging from 2.1 to 6.8%. Equine samples produced a detection rate of 11.9%, whilst feline and canine samples showed detection rates of 7.8% and 5.2%, respectively. Native animals had varying detection rates: pooled urines from flying foxes had 7.8%, whilst koalas had 5.1%, and 6.7% of ticks screened were positive. The soil and dust samples showed the presence of C. burnetii DNA ranging from 2.0 to 6.9%, respectively. These data show that specimens from a variety of animal species and the general environment provide a number of potential sources for C. burnetii infections of humans living in Queensland. These previously unrecognized sources may account for the high seroprevalence rates seen in putative low-risk communities, including Q fever patients with no direct animal contact and those subjects living in a low-risk urban environment. PMID:23663407

  6. Biological warfare agents.

    PubMed

    Pohanka, Miroslav; Kuca, Kamil

    2010-01-01

    Biological warfare agents are a group of pathogens and toxins of biological origin that can be potentially misused for military or criminal purposes. The present review attempts to summarize necessary knowledge about biological warfare agents. The historical aspects, examples of applications of these agents such as anthrax letters, biological weapons impact, a summary of biological warfare agents and epidemiology of infections are described. The last section tries to estimate future trends in research on biological warfare agents.

  7. Spacecraft sanitation agent development

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The development of an effective sanitizing agent that is compatible with the spacecraft environment and the human occupant is discussed. Experimental results show that two sanitation agents must be used to satisfy mission requirements: one agent for personal hygiene and one for equipment maintenance. It was also recommended that a water rinse be used with the agents for best results, and that consideration be given to using the agents pressure packed or in aerosol formulations.

  8. Development of Liposomal Ciprofloxacin to Treat Lung Infections.

    PubMed

    Cipolla, David; Blanchard, Jim; Gonda, Igor

    2016-01-01

    Except for management of Pseudomonas aeruginosa (PA) in cystic fibrosis, there are no approved inhaled antibiotic treatments for any other diseases or for infections from other pathogenic microorganisms such as tuberculosis, non-tuberculous mycobacteria, fungal infections or potential inhaled biowarfare agents including Francisella tularensis, Yersinia pestis and Coxiella burnetii (which cause pneumonic tularemia, plague and Q fever, respectively). Delivery of an antibiotic formulation via the inhalation route has the potential to provide high concentrations at the site of infection with reduced systemic exposure to limit side effects. A liposomal formulation may improve tolerability, increase compliance by reducing the dosing frequency, and enhance penetration of biofilms and treatment of intracellular infections. Two liposomal ciprofloxacin formulations (Lipoquin(®) and Pulmaquin(®)) that are in development by Aradigm Corporation are described here. PMID:26938551

  9. Development of Liposomal Ciprofloxacin to Treat Lung Infections

    PubMed Central

    Cipolla, David; Blanchard, Jim; Gonda, Igor

    2016-01-01

    Except for management of Pseudomonas aeruginosa (PA) in cystic fibrosis, there are no approved inhaled antibiotic treatments for any other diseases or for infections from other pathogenic microorganisms such as tuberculosis, non-tuberculous mycobacteria, fungal infections or potential inhaled biowarfare agents including Francisella tularensis, Yersinia pestis and Coxiella burnetii (which cause pneumonic tularemia, plague and Q fever, respectively). Delivery of an antibiotic formulation via the inhalation route has the potential to provide high concentrations at the site of infection with reduced systemic exposure to limit side effects. A liposomal formulation may improve tolerability, increase compliance by reducing the dosing frequency, and enhance penetration of biofilms and treatment of intracellular infections. Two liposomal ciprofloxacin formulations (Lipoquin® and Pulmaquin®) that are in development by Aradigm Corporation are described here. PMID:26938551

  10. Chemical warfare agents.

    PubMed

    Chauhan, S; Chauhan, S; D'Cruz, R; Faruqi, S; Singh, K K; Varma, S; Singh, M; Karthik, V

    2008-09-01

    Chemical warfare agents (CWA's) are defined as any chemical substance whose toxic properties are utilised to kill, injure or incapacitate an enemy in warfare and associated military operations. Chemical agents have been used in war since times immemorial, but their use reached a peak during World War I. During World War II only the Germans used them in the infamous gas chambers. Since then these have been intermittently used both in war and acts of terrorisms. Many countries have stockpiles of these agents. There has been a legislative effort worldwide to ban the use of CWA's under the chemical weapons convention which came into force in 1997. However the manufacture of these agents cannot be completely prohibited as some of them have potential industrial uses. Moreover despite the remedial measures taken so far and worldwide condemnation, the ease of manufacturing these agents and effectiveness during combat or small scale terrorist operations still make them a powerful weapon to reckon with. These agents are classified according to mechanism of toxicity in humans into blister agents, nerve agents, asphyxiants, choking agents and incapacitating/behavior altering agents. Some of these agents can be as devastating as a nuclear bomb. In addition to immediate injuries caused by chemical agents, some of them are associated with long term morbidities and psychological problems. In this review we will discuss briefly about the historical background, properties, manufacture techniques and industrial uses, mechanism of toxicity, clinical features of exposure and pharmacological management of casualties caused by chemical agents. PMID:21783898

  11. Delayed diagnosis of Q fever endocarditis in a rheumatoid arthritis patient

    PubMed Central

    Shah, Shailee Y.; Kovacs, Christopher; Tan, Carmela D.; Pettersson, Gosta; Shrestha, Nabin K.; Lutwick, Larry; Gordon, Steven M.

    2015-01-01

    Chronic Q fever caused by Coxiella burnetii is uncommon in the United States and is most often associated with infective endocarditis. We present a 52-year-old woman with a history of aortic valve replacement and rheumatoid arthritis treated with Etanercept with chronic Q fever manifesting as prosthetic valve infective endocarditis. Explanted valve tissue showed organisms confirmed to be C. burnetii by PCR (polymerase chain reaction) sequencing. She subsequently reported consumption of unpasteurized cow milk which was the likely source of C. burnetii. She continues to do well 6 months after valve replacement on oral doxycycline and hydroxychloroquine. PMID:26793469

  12. Mobile Agents Applications.

    ERIC Educational Resources Information Center

    Martins, Rosane Maria; Chaves, Magali Ribeiro; Pirmez, Luci; Rust da Costa Carmo, Luiz Fernando

    2001-01-01

    Discussion of the need to filter and retrieval relevant information from the Internet focuses on the use of mobile agents, specific software components which are based on distributed artificial intelligence and integrated systems. Surveys agent technology and discusses the agent building package used to develop two applications using IBM's Aglet…

  13. Hydroxypyridonate chelating agents

    DOEpatents

    Raymond, Kenneth N.; Scarrow, Robert C.; White, David L.

    1987-01-01

    Chelating agents having 1-hydroxy-2-pyridinone (HOPO) and related moieties incorporated within their structures, including polydentate HOPO-substituted polyamines such as spermidine and spermine, and HOPO-substituted desferrioxamine. The chelating agents are useful in selectively removing certain cations from solution, and are particularly useful as ferric ion and actinide chelators. Novel syntheses of the chelating agents are provided.

  14. Epidemiology of rickettsial diseases.

    PubMed

    Walker, D H; Fishbein, D B

    1991-05-01

    Rickettsial diseases have a diversity of epidemiologic characteristics reflective of the variety of ecologic situations in which the obligate intracellular bacteria are transmitted to humans. For the spotted fever group (SFG) rickettsiae, Rickettsia typhi, R. tsutsugamushi, Coxiella burnetii, and the human ehrlichial agent, humans are a dead-end host who plays no role in the maintenance of the organism in nature. All rickettsioses exist as zoonoses. Moreover, all rickettsiae are found in infected arthopods, which generally serve as the natural hosts and can transmit the infection to the next generation of ticks, mites, chiggers, or fleas. From our anthropocentric viewpoint, Q fever aerosol infection from parturient animals and Brill-Zinsser disease ignited epidemics of louse-borne epidemic typhus are exceptions. However, silent cycles of C. burnetii in ticks and R. prowazekii in the flying squirrel flea may have maintained these agents in transovarial or enzootic cycles for eons before humans and their domestic animals arrived on the scene. Thus, the epidemiology of rickettsial diseases must be recognized as an unfortunate aberration of the rickettsial economy. Several excellent reviews of rickettsial ecology contain a wealth of useful information. PMID:1884775

  15. Relationship between abortions and seroprevalences to selected infectious agents in dairy cows.

    PubMed

    Hässig, M; Lubsen, J

    1998-09-01

    The aim of this study was to determine whether the occurrence of abortion is related to the seroprevalence of abortion-causing infectious agents. In a cross-sectional study, cattle from dairy farms in Switzerland that were defined as having an abortion problem were divided into two groups: cows with a history of abortion within the previous 3 months (cases) and cows without a history of abortion (controls). A positive titre to Leptospira spp. was associated with an increased probability of being a case (OR = 1.74, 95% CI = 1.21-2.47). There were interactions between Coxiella burnetti titre and parity, and between Chlamydia psittaci and C. burnetti titre and breed. Multiparous cases after the second lactation with a positive titre to C. burnetti were less likely (OR = 0.42, 95% CI = 0.22-0.82) to be cases. Swiss Browns (Swiss Braunvieh and Brown Swiss) with a positive titre to C. psittaci and Swiss Browns with a positive titre to C. burnetti were more likely (OR = 1.63, 95% CI = 1.13-2.37 and OR = 1.79, 95% CI = 1.15-2.78, respectively) to be cases. Parity alone was not associated with the occurrence of abortion.

  16. Standard Agent Framework 1

    SciTech Connect

    Goldsmith, Steven Y.

    1999-04-06

    The Standard Agent framework provides an extensible object-oriented development environment suitable for use in both research and applications projects. The SAF provides a means for constructing and customizing multi-agent systems through specialization of standard base classes (architecture-driven framework) and by composition of component classes (data driven framework). The standard agent system is implemented as an extensible object-centerd framework. Four concrete base classes are developed: (1) Standard Agency; (2) Standard Agent; (3) Human Factor, and (4) Resources. The object-centered framework developed and utilized provides the best comprimise between generality and flexibility available in agent development systems today.

  17. Chronic Fatigue Syndrome (CFS): Causes

    MedlinePlus

    ... Ross River Fever, a mosquito-borne tropical disease Coxiella burnetti , the agent that causes Q fever Human ... with Epstein-Barr virus, Ross River virus, and Coxiella burnetti will lead to a post-infective condition ...

  18. Agent Architectures for Compliance

    NASA Astrophysics Data System (ADS)

    Burgemeestre, Brigitte; Hulstijn, Joris; Tan, Yao-Hua

    A Normative Multi-Agent System consists of autonomous agents who must comply with social norms. Different kinds of norms make different assumptions about the cognitive architecture of the agents. For example, a principle-based norm assumes that agents can reflect upon the consequences of their actions; a rule-based formulation only assumes that agents can avoid violations. In this paper we present several cognitive agent architectures for self-monitoring and compliance. We show how different assumptions about the cognitive architecture lead to different information needs when assessing compliance. The approach is validated with a case study of horizontal monitoring, an approach to corporate tax auditing recently introduced by the Dutch Customs and Tax Authority.

  19. Cat or Dog Ownership and Seroprevalence of Ehrlichiosis, Q Fever, and Cat-Scratch Disease

    PubMed Central

    Skerget, Martina; Daxboeck, Florian; Krause, Robert; Haberl, Renate; Stuenzner, Doris

    2003-01-01

    Concerns have been raised about the role of domestic cats or dogs in the acquisition of zoonoses, in particular in pregnant women or immune-suppressed persons. We report that cat or dog ownership is not associated with an increased seroprevalence of antibodies to Anaplasma phagozytophilum, Coxiella burnetii, and Bartonella henselae in symptom-free persons in Styria, Austria. PMID:14609477

  20. Acute meningoencephalitis as the sole manifestation of Q fever.

    PubMed

    Guerrero, M; Gutierrez, J; Carnero, C; Gonzalez-Maldonado, R; Maroto, C

    1993-01-01

    The case of a 25-year old man who presented with meningoencephalitis as the sole clinical manifestation of Q fever is described. Serological studies revealed the presence of IgM and IgG antibodies to Coxiella burnetii. The patient responded favourably to a ten-day course of i.v. ceftriaxone and was discharged without any neurological sequelae.

  1. Practical method for extraction of PCR-quality DNA from environmental soil samples.

    PubMed

    Fitzpatrick, Kelly A; Kersh, Gilbert J; Massung, Robert F

    2010-07-01

    Methods for the extraction of PCR-quality DNA from environmental soil samples by using pairs of commercially available kits were evaluated. Coxiella burnetii DNA was detected in spiked soil samples at <1,000 genome equivalents per gram of soil and in 12 (16.4%) of 73 environmental soil samples.

  2. Q Fever

    MedlinePlus

    ... chronic stages caused by the bacteria Coxiella burnetii . Cattle, sheep, and goats are the primary reservoirs although ... animals. Other modes of transmission to humans, including tick bites, ingestion of unpasteurized milk or dairy products, and human to human transmission, are rare. Humans ... Symptoms, Diagnosis, and Treatment Signs of illness, ...

  3. Multiple infections of rodents with zoonotic pathogens in Austria.

    PubMed

    Schmidt, Sabrina; Essbauer, Sandra S; Mayer-Scholl, Anne; Poppert, Sven; Schmidt-Chanasit, Jonas; Klempa, Boris; Henning, Klaus; Schares, Gereon; Groschup, Martin H; Spitzenberger, Friederike; Richter, Dania; Heckel, Gerald; Ulrich, Rainer G

    2014-07-01

    Rodents are important reservoirs for a large number of zoonotic pathogens. We examined the occurrence of 11 viral, bacterial, and parasitic agents in rodent populations in Austria, including three different hantaviruses, lymphocytic choriomeningitis virus, orthopox virus, Leptospira spp., Borrelia spp., Rickettsia spp., Bartonella spp., Coxiella burnetii, and Toxoplasma gondii. In 2008, 110 rodents of four species (40 Clethrionomys glareolus, 29 Apodemus flavicollis, 26 Apodemus sylvaticus, and 15 Microtus arvalis) were trapped at two rural sites in Lower Austria. Chest cavity fluid and samples of lung, spleen, kidney, liver, brain, and ear pinna skin were collected. We screened selected tissue samples for hantaviruses, lymphocytic choriomeningitis virus, orthopox viruses, Leptospira, Borrelia, Rickettsia, Bartonella spp., C. burnetii, and T. gondii by RT-PCR/PCR and detected nucleic acids of Tula hantavirus, Leptospira spp., Borrelia afzelii, Rickettsia spp., and different Bartonella species. Serological investigations were performed for hantaviruses, lymphocytic choriomeningitis virus, orthopox viruses, and Rickettsia spp. Here, Dobrava-Belgrade hantavirus-, Tula hantavirus-, lymphocytic choriomeningitis virus-, orthopox virus-, and rickettsia-specific antibodies were demonstrated. Puumala hantavirus, C. burnetii, and T. gondii were neither detected by RT-PCR/PCR nor by serological methods. In addition, multiple infections with up to three pathogens were shown in nine animals of three rodent species from different trapping sites. In conclusion, these results show that rodents in Austria may host multiple zoonotic pathogens. Our observation raises important questions regarding the interactions of different pathogens in the host, the countermeasures of the host's immune system, the impact of the host-pathogen interaction on the fitness of the host, and the spread of infectious agents among wild rodents and from those to other animals or humans.

  4. Multiple Infections of Rodents with Zoonotic Pathogens in Austria

    PubMed Central

    Schmidt, Sabrina; Essbauer, Sandra S.; Mayer-Scholl, Anne; Poppert, Sven; Schmidt-Chanasit, Jonas; Klempa, Boris; Henning, Klaus; Schares, Gereon; Groschup, Martin H.; Spitzenberger, Friederike; Richter, Dania; Heckel, Gerald

    2014-01-01

    Abstract Rodents are important reservoirs for a large number of zoonotic pathogens. We examined the occurrence of 11 viral, bacterial, and parasitic agents in rodent populations in Austria, including three different hantaviruses, lymphocytic choriomeningitis virus, orthopox virus, Leptospira spp., Borrelia spp., Rickettsia spp., Bartonella spp., Coxiella burnetii, and Toxoplasma gondii. In 2008, 110 rodents of four species (40 Clethrionomys glareolus, 29 Apodemus flavicollis, 26 Apodemus sylvaticus, and 15 Microtus arvalis) were trapped at two rural sites in Lower Austria. Chest cavity fluid and samples of lung, spleen, kidney, liver, brain, and ear pinna skin were collected. We screened selected tissue samples for hantaviruses, lymphocytic choriomeningitis virus, orthopox viruses, Leptospira, Borrelia, Rickettsia, Bartonella spp., C. burnetii, and T. gondii by RT-PCR/PCR and detected nucleic acids of Tula hantavirus, Leptospira spp., Borrelia afzelii, Rickettsia spp., and different Bartonella species. Serological investigations were performed for hantaviruses, lymphocytic choriomeningitis virus, orthopox viruses, and Rickettsia spp. Here, Dobrava-Belgrade hantavirus-, Tula hantavirus-, lymphocytic choriomeningitis virus-, orthopox virus-, and rickettsia-specific antibodies were demonstrated. Puumala hantavirus, C. burnetii, and T. gondii were neither detected by RT-PCR/PCR nor by serological methods. In addition, multiple infections with up to three pathogens were shown in nine animals of three rodent species from different trapping sites. In conclusion, these results show that rodents in Austria may host multiple zoonotic pathogens. Our observation raises important questions regarding the interactions of different pathogens in the host, the countermeasures of the host's immune system, the impact of the host–pathogen interaction on the fitness of the host, and the spread of infectious agents among wild rodents and from those to other animals or humans. PMID

  5. Multiple infections of rodents with zoonotic pathogens in Austria.

    PubMed

    Schmidt, Sabrina; Essbauer, Sandra S; Mayer-Scholl, Anne; Poppert, Sven; Schmidt-Chanasit, Jonas; Klempa, Boris; Henning, Klaus; Schares, Gereon; Groschup, Martin H; Spitzenberger, Friederike; Richter, Dania; Heckel, Gerald; Ulrich, Rainer G

    2014-07-01

    Rodents are important reservoirs for a large number of zoonotic pathogens. We examined the occurrence of 11 viral, bacterial, and parasitic agents in rodent populations in Austria, including three different hantaviruses, lymphocytic choriomeningitis virus, orthopox virus, Leptospira spp., Borrelia spp., Rickettsia spp., Bartonella spp., Coxiella burnetii, and Toxoplasma gondii. In 2008, 110 rodents of four species (40 Clethrionomys glareolus, 29 Apodemus flavicollis, 26 Apodemus sylvaticus, and 15 Microtus arvalis) were trapped at two rural sites in Lower Austria. Chest cavity fluid and samples of lung, spleen, kidney, liver, brain, and ear pinna skin were collected. We screened selected tissue samples for hantaviruses, lymphocytic choriomeningitis virus, orthopox viruses, Leptospira, Borrelia, Rickettsia, Bartonella spp., C. burnetii, and T. gondii by RT-PCR/PCR and detected nucleic acids of Tula hantavirus, Leptospira spp., Borrelia afzelii, Rickettsia spp., and different Bartonella species. Serological investigations were performed for hantaviruses, lymphocytic choriomeningitis virus, orthopox viruses, and Rickettsia spp. Here, Dobrava-Belgrade hantavirus-, Tula hantavirus-, lymphocytic choriomeningitis virus-, orthopox virus-, and rickettsia-specific antibodies were demonstrated. Puumala hantavirus, C. burnetii, and T. gondii were neither detected by RT-PCR/PCR nor by serological methods. In addition, multiple infections with up to three pathogens were shown in nine animals of three rodent species from different trapping sites. In conclusion, these results show that rodents in Austria may host multiple zoonotic pathogens. Our observation raises important questions regarding the interactions of different pathogens in the host, the countermeasures of the host's immune system, the impact of the host-pathogen interaction on the fitness of the host, and the spread of infectious agents among wild rodents and from those to other animals or humans. PMID:24915446

  6. 13 CFR 107.1620 - Functions of agents, including Central Registration Agent, Selling Agent and Fiscal Agent.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Functions of agents, including... Assistance SMALL BUSINESS ADMINISTRATION SMALL BUSINESS INVESTMENT COMPANIES SBA Financial Assistance for... Functions of agents, including Central Registration Agent, Selling Agent and Fiscal Agent. (a) Agents....

  7. Detecting biological warfare agents.

    PubMed

    Song, Linan; Ahn, Soohyoun; Walt, David R

    2005-10-01

    We developed a fiber-optic, microsphere-based, high-density array composed of 18 species-specific probe microsensors to identify biological warfare agents. We simultaneously identified multiple biological warfare agents in environmental samples by looking at specific probe responses after hybridization and response patterns of the multiplexed array.

  8. Travel Agent Course Outline.

    ERIC Educational Resources Information Center

    British Columbia Dept. of Education, Victoria.

    Written for college entry-level travel agent training courses, this course outline can also be used for inservice training programs offered by travel agencies. The outline provides information on the work of a travel agent and gives clear statements on what learners must be able to do by the end of their training. Material is divided into eight…

  9. Change Agent Survival Guide

    ERIC Educational Resources Information Center

    Dunbar, Folwell L.

    2011-01-01

    Consulting is a rough racket. Only a tarantula hair above IRS agents, meter maids and used car sales people, the profession is a prickly burr for slings and arrows. Throw in education, focus on dysfunctional schools and call oneself a "change agent," and this bad rap all but disappears. Unfortunately, though, consulting/coaching/mentoring in…

  10. Ferrimagnetic susceptibility contrast agents.

    PubMed

    Bach-Gansmo, T

    1993-01-01

    Contrast agents based on superparamagnetic particles have been in clinical development for more than 5 years, and the complexity of their effects is still not elucidated. The relaxivities are frequently used to give an idea of their efficacy, but these parameters can only be used if they are concentration independent. For large superparamagnetic systems, the evolution of the transverse magnetization is biexponential, after an initial loss of magnetization. Both these characteristics of large superparamagnetic systems should lead to prudence in using the relaxivities as indicators of contrast medium efficacy. Susceptibility induced artefacts have been associated with the use of superparamagnetic contrast agents since the first imaging evaluation took place. The range of concentrations where good contrast effect was achieved without inducing artefacts, as well as blurring and metal artefacts were evaluated. The influence of motion on the induction of artefacts was studied, and compared to the artefacts induced by a paramagnetic agent subject to motion. With a suitable concentration of a negative contrast agent, a signal void could be achieved in the region prone to motion, and no artefacts were induced. If the concentration was too high, a displacement of the region close to the contrast agent was observed. The artefacts occurred in a volume surrounding the contrast agent, i.e., also outside the imaging plane. In comparison a positive, paramagnetic contrast agent induced heavy artefacts in the phase encoding direction, appearing as both high intensity regions and black holes, in a mosaic pattern. Clinical trials of the oral contrast agent OMP for abdominal MR imaging showed this agent to be safe and efficacious. OMP increased the diagnostic efficacy of abdominal MR imaging in 2 of 3 cases examined, with a significant decrease in motion artefacts. Susceptibility contrast agents may also be of use in the evaluation of small lesions in the liver. Particulate material

  11. Zoonotic infections in communities of the James Bay Cree territory: An overview of seroprevalence

    PubMed Central

    Sampasa-Kanyinga, Hugues; Lévesque, Benoit; Anassour-Laouan-Sidi, Elhadji; Côté, Suzanne; Serhir, Bouchra; Ward, Brian J; Libman, Michael D; Drebot, Michael A; Makowski, Kai; Dimitrova, Kristina; Ndao, Momar; Dewailly, Éric

    2013-01-01

    The Cree communities of James Bay are at risk for contracting infectious diseases transmitted by wildlife. Data from serological testing for a range of zoonotic infections performed in the general population (six communities), or trappers and their spouses (one community), were abstracted from four population-based studies conducted in Cree territory (Quebec) between 2005 and 2009. Evidence of exposure to Trichinella species, Toxoplasma gondii, Toxocara canis, Echinococcus granulosus, Leptospira species, Coxiella burnetii and Francisella tularensis was verified in all communities, whereas antibodies against Sin Nombre virus and California serogroup viruses (Jamestown Canyon and snowshoe hare viruses) were evaluated in three and six communities, respectively. Seroprevalence varied widely among communities: snowshoe hare virus (1% to 42%), F tularensis (14% to 37%), Leptospira species (10% to 27%), Jamestown Canyon virus (9% to 24%), C burnetii (0% to 18%), T gondii (4% to 12%), T canis (0% to 10%), E granulosus (0% to 4%) and Trichinella species (0% to 1%). No subject had serological evidence of Sin Nombre virus exposure. These data suggest that large proportions of the Cree population have been exposed to at least one of the targeted zoonotic agents. The Cree population, particularly those most heavily exposed to fauna, as well as the medical staff living in these regions, should be aware of these diseases. Greater awareness would not only help to decrease exposures but would also increase the chance of appropriate diagnostic testing. PMID:24421806

  12. Host-Directed Antimicrobial Drugs with Broad-Spectrum Efficacy against Intracellular Bacterial Pathogens

    PubMed Central

    Czyż, Daniel M.; Potluri, Lakshmi-Prasad; Jain-Gupta, Neeta; Riley, Sean P.; Martinez, Juan J.; Steck, Theodore L.; Crosson, Sean; Gabay, Joëlle E.

    2014-01-01

    ABSTRACT We sought a new approach to treating infections by intracellular bacteria, namely, by altering host cell functions that support their growth. We screened a library of 640 Food and Drug Administration (FDA)-approved compounds for agents that render THP-1 cells resistant to infection by four intracellular pathogens. We identified numerous drugs that are not antibiotics but were highly effective in inhibiting intracellular bacterial growth with limited toxicity to host cells. These compounds are likely to target three kinds of host functions: (i) G protein-coupled receptors, (ii) intracellular calcium signals, and (iii) membrane cholesterol distribution. The compounds that targeted G protein receptor signaling and calcium fluxes broadly inhibited Coxiella burnetii, Legionella pneumophila, Brucella abortus, and Rickettsia conorii, while those directed against cholesterol traffic strongly attenuated the intracellular growth of C. burnetii and L. pneumophila. These pathways probably support intracellular pathogen growth so that drugs that perturb them may be therapeutic candidates. Combining host- and pathogen-directed treatments is a strategy to decrease the emergence of drug-resistant intracellular bacterial pathogens. PMID:25073644

  13. Molecular evidence of vector-borne pathogens in dogs and cats and their ectoparasites in Algiers, Algeria.

    PubMed

    Bessas, Amina; Leulmi, Hamza; Bitam, Idir; Zaidi, Sara; Ait-Oudhia, Khatima; Raoult, Didier; Parola, Philippe

    2016-04-01

    In Algeria, only limited information is currently available on the prevalence of emergent canine and feline vector-borne diseases. The aim of the present work was to detect by qPCR vector-associated bacteria in stray dogs and cats and their ectoparasites from Algiers. 18/117 (15.38%) dogs and 2/107 (1.87%) cats were positive for at least one vector-borne agent. Coxiella burnetii and Bartonella henselae were identified in 1/117 (0.85%) dog individually. Ehrlichia canis DNA was detected in 17/117 (14.52%) dogs. 1/107 (0.93%) cat was positive to C. burnetii and another 1/107 (0.93%) to B. henselae. DNA of Rickettsia massiliae, Rickettsia conorii and E. canis was detected in Rhipicephalus sanguineus. Cat fleas were infected with Rickettsia felis, B. henselae and Bartonella clarridgeiae. B. vinsonii subsp. berkhoffii was identified in Xenopsylla cheopis collected from dogs. The findings of this study indicate that dogs and cats from Algeria are exposed to multiple tick and flea-borne pathogens.

  14. Molecular evidence of vector-borne pathogens in dogs and cats and their ectoparasites in Algiers, Algeria.

    PubMed

    Bessas, Amina; Leulmi, Hamza; Bitam, Idir; Zaidi, Sara; Ait-Oudhia, Khatima; Raoult, Didier; Parola, Philippe

    2016-04-01

    In Algeria, only limited information is currently available on the prevalence of emergent canine and feline vector-borne diseases. The aim of the present work was to detect by qPCR vector-associated bacteria in stray dogs and cats and their ectoparasites from Algiers. 18/117 (15.38%) dogs and 2/107 (1.87%) cats were positive for at least one vector-borne agent. Coxiella burnetii and Bartonella henselae were identified in 1/117 (0.85%) dog individually. Ehrlichia canis DNA was detected in 17/117 (14.52%) dogs. 1/107 (0.93%) cat was positive to C. burnetii and another 1/107 (0.93%) to B. henselae. DNA of Rickettsia massiliae, Rickettsia conorii and E. canis was detected in Rhipicephalus sanguineus. Cat fleas were infected with Rickettsia felis, B. henselae and Bartonella clarridgeiae. B. vinsonii subsp. berkhoffii was identified in Xenopsylla cheopis collected from dogs. The findings of this study indicate that dogs and cats from Algeria are exposed to multiple tick and flea-borne pathogens. PMID:27012917

  15. Standard Agent Framework 1

    1999-04-06

    The Standard Agent framework provides an extensible object-oriented development environment suitable for use in both research and applications projects. The SAF provides a means for constructing and customizing multi-agent systems through specialization of standard base classes (architecture-driven framework) and by composition of component classes (data driven framework). The standard agent system is implemented as an extensible object-centerd framework. Four concrete base classes are developed: (1) Standard Agency; (2) Standard Agent; (3) Human Factor, and (4)more » Resources. The object-centered framework developed and utilized provides the best comprimise between generality and flexibility available in agent development systems today.« less

  16. How do agents represent?

    NASA Astrophysics Data System (ADS)

    Ryan, Alex

    Representation is inherent to the concept of an agent, but its importance in complex systems has not yet been widely recognised. In this paper I introduce Peirce's theory of signs, which facilitates a definition of representation in general. In summary, representation means that for some agent, a model is used to stand in for another entity in a way that shapes the behaviour of the agent with respect to that entity. Representation in general is then related to the theories of representation that have developed within different disciplines. I compare theories of representation from metaphysics, military theory and systems theory. Additional complications arise in explaining the special case of mental representations, which is the focus of cognitive science. I consider the dominant theory of cognition — that the brain is a representational device — as well as the sceptical anti-representational response. Finally, I argue that representation distinguishes agents from non-representational objects: agents are objects capable of representation.

  17. Biological warfare agents.

    PubMed

    Thavaselvam, Duraipandian; Vijayaraghavan, Rajagopalan

    2010-07-01

    The recent bioterrorist attacks using anthrax spores have emphasized the need to detect and decontaminate critical facilities in the shortest possible time. There has been a remarkable progress in the detection, protection and decontamination of biological warfare agents as many instrumentation platforms and detection methodologies are developed and commissioned. Even then the threat of biological warfare agents and their use in bioterrorist attacks still remain a leading cause of global concern. Furthermore in the past decade there have been threats due to the emerging new diseases and also the re-emergence of old diseases and development of antimicrobial resistance and spread to new geographical regions. The preparedness against these agents need complete knowledge about the disease, better research and training facilities, diagnostic facilities and improved public health system. This review on the biological warfare agents will provide information on the biological warfare agents, their mode of transmission and spread and also the detection systems available to detect them. In addition the current information on the availability of commercially available and developing technologies against biological warfare agents has also been discussed. The risk that arise due to the use of these agents in warfare or bioterrorism related scenario can be mitigated with the availability of improved detection technologies.

  18. Biological warfare agents

    PubMed Central

    Thavaselvam, Duraipandian; Vijayaraghavan, Rajagopalan

    2010-01-01

    The recent bioterrorist attacks using anthrax spores have emphasized the need to detect and decontaminate critical facilities in the shortest possible time. There has been a remarkable progress in the detection, protection and decontamination of biological warfare agents as many instrumentation platforms and detection methodologies are developed and commissioned. Even then the threat of biological warfare agents and their use in bioterrorist attacks still remain a leading cause of global concern. Furthermore in the past decade there have been threats due to the emerging new diseases and also the re-emergence of old diseases and development of antimicrobial resistance and spread to new geographical regions. The preparedness against these agents need complete knowledge about the disease, better research and training facilities, diagnostic facilities and improved public health system. This review on the biological warfare agents will provide information on the biological warfare agents, their mode of transmission and spread and also the detection systems available to detect them. In addition the current information on the availability of commercially available and developing technologies against biological warfare agents has also been discussed. The risk that arise due to the use of these agents in warfare or bioterrorism related scenario can be mitigated with the availability of improved detection technologies. PMID:21829313

  19. Dioxin, agent orange

    SciTech Connect

    Gough, M.

    1986-01-01

    This book presents information on the following topics: dioxin, a prevalent problem; nobody wanted dioxin; agent organe and Vietnam; what we know about and may learn about agent orange and Veterans' health; agent organe and birth defects; dioxin in Missouri; 2, 4, 5-T: the U.S.' disappearing herbicide; Seveso: high-level environmental exposure; the nitro explosion; industrial exposures to dioxin; company behavior in the face of dioxin exposures; dioxin and specific cancers; animal tests of dioxin toxicity; dioxin decions; the present and the future.

  20. Riot Control Agents

    MedlinePlus

    ... your clothing, rapidly wash your entire body with soap and water, and get medical care as quickly ... agent from your skin with large amounts of soap and water. Washing with soap and water will ...

  1. Radioactive diagnostic agent

    SciTech Connect

    Shigematsu, A.; Aihara, M.; Matsuda, M.; Suzuki, A.; Tsuya, A.

    1984-02-07

    A radioactive diagnostic agent for renal cortex, adrenal cortex, myocardium, brain stem, spinal nerve, etc., which comprises as an essential component monoiodoacetic acid wherein the iodine atom is radioactive.

  2. Agent oriented programming

    NASA Technical Reports Server (NTRS)

    Shoham, Yoav

    1994-01-01

    The goal of our research is a methodology for creating robust software in distributed and dynamic environments. The approach taken is to endow software objects with explicit information about one another, to have them interact through a commitment mechanism, and to equip them with a speech-acty communication language. System-level applications include software interoperation and compositionality. A government application of specific interest is an infrastructure for coordination among multiple planners. Daily activity applications include personal software assistants, such as programmable email, scheduling, and new group agents. Research topics include definition of mental state of agents, design of agent languages as well as interpreters for those languages, and mechanisms for coordination within agent societies such as artificial social laws and conventions.

  3. Emergence of Q fever arthritis in France.

    PubMed

    Angelakis, Emmanouil; Edouard, Sophie; Lafranchi, Marie-Alix; Pham, Thao; Lafforgue, Pierre; Raoult, Didier

    2014-04-01

    Osteoarticular infection is an uncommon presentation of Q fever. Positron emission tomography (PET) scanning is a valuable tool for the diagnosis of Coxiella burnetii graft prosthesis infection and endocarditis. Our objective was to test a series of culture-negative osteoarticular samples using molecular assays for Coxiella burnetii. We tested for C. burnetii by molecular assays targeting the IS1111 and the IS30A spacer regions, using culture-negative osteoarticular samples obtained in our laboratory between January 2011 and December 2012. We examine a total of 1,410 osteoarticular samples, and we observed two cases of arthritis and subacromial bursitis caused by C. burnetii. The infections were localized using PET scanning, and the diagnosis was confirmed through serology. For one, a C. burnetii strain with a multispacer sequence type 8 genotype was isolated from synovial fluid culture. Q fever articular infections could be undiagnosed because of the long evolution of articular attack, and patients with high antibody titers against C. burnetii should be tested using PET scanning to localize the site of infection.

  4. Agent amplified communication

    SciTech Connect

    Kautz, H.; Selman, B.; Milewski, A.

    1996-12-31

    We propose an agent-based framework for assisting and simplifying person-to-person communication for information gathering tasks. As an example, we focus on locating experts for any specified topic. In our approach, the informal person-to-person networks that exist within an organization are used to {open_quotes}referral chain{close_quotes} requests for expertise. User-agents help automate this process. The agents generate referrals by analyzing records of e-mail communication patterns. Simulation results show that the higher responsiveness of an agent-based system can be effectively traded for the higher accuracy of a completely manual approach. Furthermore, preliminary experience with a group of users on a prototype system has shown that useful automatic referrals can be found in practice. Our experience with actual users has also shown that privacy concerns are central to the successful deployment of personal agents: an advanced agent-based system will therefore need to reason about issues involving trust and authority.

  5. Agent independent task planning

    NASA Technical Reports Server (NTRS)

    Davis, William S.

    1990-01-01

    Agent-Independent Planning is a technique that allows the construction of activity plans without regard to the agent that will perform them. Once generated, a plan is then validated and translated into instructions for a particular agent, whether a robot, crewmember, or software-based control system. Because Space Station Freedom (SSF) is planned for orbital operations for approximately thirty years, it will almost certainly experience numerous enhancements and upgrades, including upgrades in robotic manipulators. Agent-Independent Planning provides the capability to construct plans for SSF operations, independent of specific robotic systems, by combining techniques of object oriented modeling, nonlinear planning and temporal logic. Since a plan is validated using the physical and functional models of a particular agent, new robotic systems can be developed and integrated with existing operations in a robust manner. This technique also provides the capability to generate plans for crewmembers with varying skill levels, and later apply these same plans to more sophisticated robotic manipulators made available by evolutions in technology.

  6. Sunscreening agents: a review.

    PubMed

    Latha, M S; Martis, Jacintha; Shobha, V; Sham Shinde, Rutuja; Bangera, Sudhakar; Krishnankutty, Binny; Bellary, Shantala; Varughese, Sunoj; Rao, Prabhakar; Naveen Kumar, B R

    2013-01-01

    The increasing incidence of skin cancers and photodamaging effects caused by ultraviolet radiation has increased the use of sunscreening agents, which have shown beneficial effects in reducing the symptoms and reoccurrence of these problems. Many sunscreen compounds are in use, but their safety and efficacy are still in question. Efficacy is measured through indices, such as sun protection factor, persistent pigment darkening protection factor, and COLIPA guidelines. The United States Food and Drug Administration and European Union have incorporated changes in their guidelines to help consumers select products based on their sun protection factor and protection against ultraviolet radiation, whereas the Indian regulatory agency has not yet issued any special guidance on sunscreening agents, as they are classified under cosmetics. In this article, the authors discuss the pharmacological actions of sunscreening agents as well as the available formulations, their benefits, possible health hazards, safety, challenges, and proper application technique. New technologies and scope for the development of sunscreening agents are also discussed as well as the role of the physician in patient education about the use of these agents.

  7. MpcAgent

    2013-11-29

    MpcAgent software is a module for the VolltronLite platform from PNNL that regulates the operation of rooftop air conditioning units in small to medium commercial buildings for the purpose of reducing peak power consumption. The MpcAgent accomplishes this by restricting the number of units that may operate simultaneously and using a model predictive control strategy to select which units to operate in each control period. The outcome of this control is effective control of themore » building air temperature at the user specified set point while avoiding expensive peak demand charges that result from running all HVAC units simultaneously.« less

  8. MpcAgent

    SciTech Connect

    Nutaro, James

    2013-11-29

    MpcAgent software is a module for the VolltronLite platform from PNNL that regulates the operation of rooftop air conditioning units in small to medium commercial buildings for the purpose of reducing peak power consumption. The MpcAgent accomplishes this by restricting the number of units that may operate simultaneously and using a model predictive control strategy to select which units to operate in each control period. The outcome of this control is effective control of the building air temperature at the user specified set point while avoiding expensive peak demand charges that result from running all HVAC units simultaneously.

  9. Agent Persuasion Mechanism of Acquaintance

    NASA Astrophysics Data System (ADS)

    Jinghua, Wu; Wenguang, Lu; Hailiang, Meng

    Agent persuasion can improve negotiation efficiency in dynamic environment based on its initiative and autonomy, and etc., which is being affected much more by acquaintance. Classification of acquaintance on agent persuasion is illustrated, and the agent persuasion model of acquaintance is also illustrated. Then the concept of agent persuasion degree of acquaintance is given. Finally, relative interactive mechanism is elaborated.

  10. 13 CFR 108.1620 - Functions of agents, including Central Registration Agent, Selling Agent and Fiscal Agent.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Functions of agents, including Central Registration Agent, Selling Agent and Fiscal Agent. 108.1620 Section 108.1620 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION NEW MARKETS VENTURE CAPITAL (âNMVCâ) PROGRAM SBA...

  11. Battlefield agent collaboration

    NASA Astrophysics Data System (ADS)

    Budulas, Peter P.; Young, Stuart H.; Emmerman, Philip J.

    2001-09-01

    Small air and ground physical agents (robots) will be ubiquitous on the battlefield of the 21st century, principally to lower the exposure to harm of our ground forces in urban and open terrain scenarios. Teams of small collaborating physical agents conducting tasks such as Reconnaissance, Surveillance, and Target Acquisition (RSTA), intelligence, chemical and biological agent detection, logistics, decoy, sentry; and communications relay will have advanced sensors, communications, and mobility characteristics. It is anticipated that there will be many levels of individual and team collaboration between the soldier and robot, robot to robot, and robot to mother ship. This paper presents applications and infrastructure components that illustrate each of these levels. As an example, consider the application where a team of twenty small robots must rapidly explore and define a building complex. Local interactions and decisions require peer to peer collaboration. Global direction and information fusion warrant a central team control provided by a mother ship. The mother ship must effectively deliver/retrieve, service, and control these robots as well as fuse the information gathered by these highly mobile robot teams. Any level of collaboration requires robust communications, specifically a mobile ad hoc network. The application of fixed ground sensors and mobile robots is also included in this paper. This paper discusses on going research at the U.S. Army Research Laboratory that supports the development of multi-robot collaboration. This research includes battlefield visualization, intelligent software agents, adaptive communications, sensor and information fusion, and multi-modal human computer interaction.

  12. Mobility control agent

    SciTech Connect

    Argabright, P.A.; Phillips, B.L.; Rhudy, J.S.

    1983-05-17

    Polymer mobility control agents useful in supplemental oil recovery processes, which give improved reciprocal relative mobilities, are prepared by initiating the polymerization of a monomer containing a vinyl group with a catalyst comprising a persulfate and ferrous ammonium sulfate. The vinyl monomer is an acrylyl, a vinyl cyanide, a styryl and water soluble salts thereof.

  13. E-Learning Agents

    ERIC Educational Resources Information Center

    Gregg, Dawn G.

    2007-01-01

    Purpose: The purpose of this paper is to illustrate the advantages of using intelligent agents to facilitate the location and customization of appropriate e-learning resources and to foster collaboration in e-learning environments. Design/methodology/approach: This paper proposes an e-learning environment that can be used to provide customized…

  14. Remote Agent Experiment

    NASA Technical Reports Server (NTRS)

    Benard, Doug; Dorais, Gregory A.; Gamble, Ed; Kanefsky, Bob; Kurien, James; Millar, William; Muscettola, Nicola; Nayak, Pandu; Rouquette, Nicolas; Rajan, Kanna; Norvig, Peter (Technical Monitor)

    2000-01-01

    Remote Agent (RA) is a model-based, reusable artificial intelligence (At) software system that enables goal-based spacecraft commanding and robust fault recovery. RA was flight validated during an experiment on board of DS1 between May 17th and May 21th, 1999.

  15. Can Subscription Agents Survive?

    ERIC Educational Resources Information Center

    Tuttle, Marcia

    1985-01-01

    With the saturation of traditional markets for their services, subscription agents have evolved from orders and invoices to serving customers by communicating with librarians and publishers and making automated and paper products available. Magazine fulfillment centers, publisher discounts, and electronic publishing will influence the subscription…

  16. Emulsified blasting agents

    SciTech Connect

    Chironis, N.P.

    1985-01-01

    This article describes an improved blasting agent which is being tailor-blended with bulk ANFO to provide more explosive energy and better water resistance when the blasting conditions call for it. The proportions of the emulsion/ANFO mix are easily changed at the blasthole site because both materials can be selectively mixed in modified bulk-explosive trucks before loading the blasting agents into the holes. Such blends are helping speed stripping at a number of surface mines and are leading to cost savings in production, ranging from 10% to 30%, depending upon application, even though the actual cost of a blend will be higher than if bulk ANFO is used alone.

  17. Rigid bifunctional chelating agents

    DOEpatents

    Sweet, Mark P.; Mease, Ronnie C.; Srivastava, Suresh C.

    2000-02-08

    Bicyclo[2.2.2]octane-2,3 diamine-N,N,N',N'-tetraacetic acids (BODTA) and bicyclo[2.2.1]heptane-2,3 diamine-N,N,N',N'-tetraacetic acid (BHDTA) are chelating agents useful in forming detectably labeled bioconjugate compounds for diagnostic and therapeutic purposes. New compounds and processes of forming BODTA and BHDTA are disclosed. Radioimmunoconjugates of the present invention show high and prolonged tumor uptake with low normal tissue uptakes.

  18. Rigid bifunctional chelating agents

    DOEpatents

    Sweet, M.P.; Mease, R.C.; Srivastava, S.C.

    1998-07-21

    Bicyclo[2.2.2] octane-2,3 diamine-N,N,N`,N`-tetraacetic acids (BODTA) and bicyclo[2.2.1] heptane-2,3 diamine-N,N,N`,N`-tetraacetic acid (BHDTA) are chelating agents useful in forming detectably labeled bioconjugate compounds for diagnostic and therapeutic purposes. New compounds and processes of forming BODTA and BHDTA are disclosed. Radioimmunoconjugates of the present invention show high and prolonged tumor uptake with low normal tissue uptakes.

  19. Rigid bifunctional chelating agents

    DOEpatents

    Sweet, Mark P.; Mease, Ronnie C.; Srivastava, Suresh C.

    1998-07-21

    Bicyclo›2.2.2! octane-2,3 diamine-N,N,N',N'-tetraacetic acids (BODTA) and bicyclo›2.2.1! heptane-2,3 diamine-N,N,N',N'-tetraacetic acid (BHDTA) are chelating agents useful in forming detectably labeled bioconjugate compounds for diagnostic and therapeutic purposes. New compounds and processes of forming BODTA and BHDTA are disclosed. Radioimmunoconjugates of the present invention show high and prolonged tumor uptake with low normal tissue uptakes.

  20. Surface polymerization agents

    SciTech Connect

    Taylor, C.; Wilkerson, C.

    1996-12-01

    This is the final report of a 1-year, Laboratory-Directed R&D project at LANL. A joint technical demonstration was proposed between US Army Missile Command (Redstone Arsenal) and LANL. Objective was to demonstrate that an unmanned vehicle or missile could be used as a platform to deliver a surface polymerization agent in such a manner as to obstruct the filters of an air-breathing mechanism, resulting in operational failure.

  1. Collaborating with Autonomous Agents

    NASA Technical Reports Server (NTRS)

    Trujillo, Anna C.; Cross, Charles D.; Fan, Henry; Hempley, Lucas E.; Motter, Mark A.; Neilan, James H.; Qualls, Garry D.; Rothhaar, Paul M.; Tran, Loc D.; Allen, B. Danette

    2015-01-01

    With the anticipated increase of small unmanned aircraft systems (sUAS) entering into the National Airspace System, it is highly likely that vehicle operators will be teaming with fleets of small autonomous vehicles. The small vehicles may consist of sUAS, which are 55 pounds or less that typically will y at altitudes 400 feet and below, and small ground vehicles typically operating in buildings or defined small campuses. Typically, the vehicle operators are not concerned with manual control of the vehicle; instead they are concerned with the overall mission. In order for this vision of high-level mission operators working with fleets of vehicles to come to fruition, many human factors related challenges must be investigated and solved. First, the interface between the human operator and the autonomous agent must be at a level that the operator needs and the agents can understand. This paper details the natural language human factors e orts that NASA Langley's Autonomy Incubator is focusing on. In particular these e orts focus on allowing the operator to interact with the system using speech and gestures rather than a mouse and keyboard. With this ability of the system to understand both speech and gestures, operators not familiar with the vehicle dynamics will be able to easily plan, initiate, and change missions using a language familiar to them rather than having to learn and converse in the vehicle's language. This will foster better teaming between the operator and the autonomous agent which will help lower workload, increase situation awareness, and improve performance of the system as a whole.

  2. Hydroxypyridonate and hydroxypyrimidinone chelating agents

    DOEpatents

    Raymond, Kenneth N.; Doble, Daniel M.; Sunderland, Christopher J.; Thompson, Marlon

    2005-01-25

    The present invention provides hydroxypyridinone and hydroxypyrimidone chelating agents. Also provides are Gd(III) complexes of these agents, which are useful as contrast enhancing agents for magnetic resonance imaging. The invention also provides methods of preparing the compounds of the invention, as well as methods of using the compounds in magnetic resonance imaging applications.

  3. Chemical warfare agents

    PubMed Central

    Ganesan, K.; Raza, S. K.; Vijayaraghavan, R.

    2010-01-01

    Among the Weapons of Mass Destruction, chemical warfare (CW) is probably one of the most brutal created by mankind in comparison with biological and nuclear warfare. Chemical weapons are inexpensive and are relatively easy to produce, even by small terrorist groups, to create mass casualties with small quantities. The characteristics of various CW agents, general information relevant to current physical as well as medical protection methods, detection equipment available and decontamination techniques are discussed in this review article. A brief note on Chemical Weapons Convention is also provided. PMID:21829312

  4. Holograms as Teaching Agents

    NASA Astrophysics Data System (ADS)

    Walker, Robin A.

    2013-02-01

    Hungarian physicist Dennis Gabor won the Pulitzer Prize for his 1947 introduction of basic holographic principles, but it was not until the invention of the laser in 1960 that research scientists, physicians, technologists and the general public began to seriously consider the interdisciplinary potentiality of holography. Questions around whether and when Three-Dimensional (3-D) images and systems would impact American entertainment and the arts would be answered before educators, instructional designers and students would discover how much Three-Dimensional Hologram Technology (3DHT) would affect teaching practices and learning environments. In the following International Symposium on Display Holograms (ISDH) poster presentation, the author features a traditional board game as well as a reflection hologram to illustrate conventional and evolving Three-Dimensional representations and technology for education. Using elements from the American children's toy Operation® (Hasbro, 2005) as well as a reflection hologram of a human brain (Ko, 1998), this poster design highlights the pedagogical effects of 3-D images, games and systems on learning science. As teaching agents, holograms can be considered substitutes for real objects, (human beings, organs, and animated characters) as well as agents (pedagogical, avatars, reflective) in various learning environments using many systems (direct, emergent, augmented reality) and electronic tools (cellphones, computers, tablets, television). In order to understand the particular importance of utilizing holography in school, clinical and public settings, the author identifies advantages and benefits of using 3-D images and technology as instructional tools.

  5. Lipid-lowering agents.

    PubMed

    Ewang-Emukowhate, Mfon; Wierzbicki, Anthony S

    2013-09-01

    The role of lipid lowering in reducing the risk of mortality and morbidity from cardiovascular disease (CVD) is well established. Treatment particularly aimed at decreasing low-density lipoprotein cholesterol (LDL-C) is effective in reducing the risk of death from coronary heart disease and stroke. Statins form the cornerstone of treatment. However, in some individuals with a high risk of CVD who are unable to achieve their target LDL-C due to either intolerance or lack of efficacy, there is the need for alternative therapies. This review provides an overview of the different classes of currently available lipid-lowering medications including statins, fibrates, bile acid sequestrants (resins), and omega-3 fatty acids. Data are presented on their indications, pharmacology, and the relevant end point clinical trial data with these drugs. It also discusses the human trial data on some novel therapeutic agents that are being developed including those for homozygous familial hypercholesterolemia--the antisense oligonucleotide mipomersen and the microsomal transfer protein inhibitor lomitapide. Data are presented on phase II and III trials on agents with potentially wider applications, cholesterol ester transfer protein inhibitors and proprotein convertase subtilisin kexin 9 inhibitors. The data on a licensed gene therapy for lipoprotein lipase deficiency are also presented. PMID:23811423

  6. [Bacteriophages as antibacterial agents].

    PubMed

    Shasha, Shaul M; Sharon, Nehama; Inbar, Michael

    2004-02-01

    Bacteriophages are viruses that only infect bacteria. They have played an important role in the development of molecular biology and have been used as anti-bacterial agents. Since their independent discovery by Twort and d'Herelle, they have been extensively used to prevent and treat bacterial infections, mainly in Eastern Europe and the former Soviet Union. In western countries this method has been sporadically employed on humans and domesticated animals. However, the discovery and widespread use of antibiotics, coupled with doubts about the efficacy of phage therapy, led to an eclipse in the use of phage in medicine. The emergence of antibiotic resistant bacteria, especially strains that are multiply resistant, has resulted in a renewed interest in alternatives to conventional drugs. One of the possible replacements for antibiotics is the use of bacteriophages as antimicrobial agents. This brief review aims to describe the history of bacteriophage and early clinical studies on their use in bacterial disease prophylaxis and therapy, and discuss the advantages and disadvantages of bacteriophage in this regard.

  7. Lipid-lowering agents.

    PubMed

    Ewang-Emukowhate, Mfon; Wierzbicki, Anthony S

    2013-09-01

    The role of lipid lowering in reducing the risk of mortality and morbidity from cardiovascular disease (CVD) is well established. Treatment particularly aimed at decreasing low-density lipoprotein cholesterol (LDL-C) is effective in reducing the risk of death from coronary heart disease and stroke. Statins form the cornerstone of treatment. However, in some individuals with a high risk of CVD who are unable to achieve their target LDL-C due to either intolerance or lack of efficacy, there is the need for alternative therapies. This review provides an overview of the different classes of currently available lipid-lowering medications including statins, fibrates, bile acid sequestrants (resins), and omega-3 fatty acids. Data are presented on their indications, pharmacology, and the relevant end point clinical trial data with these drugs. It also discusses the human trial data on some novel therapeutic agents that are being developed including those for homozygous familial hypercholesterolemia--the antisense oligonucleotide mipomersen and the microsomal transfer protein inhibitor lomitapide. Data are presented on phase II and III trials on agents with potentially wider applications, cholesterol ester transfer protein inhibitors and proprotein convertase subtilisin kexin 9 inhibitors. The data on a licensed gene therapy for lipoprotein lipase deficiency are also presented.

  8. [New agents for hypercholesterolemia].

    PubMed

    Pintó, Xavier; García Gómez, María Carmen

    2016-02-19

    An elevated proportion of high cardiovascular risk patients do not achieve the therapeutic c-LDL goals. This owes to physicians' inappropriate or insufficient use of cholesterol lowering medications or to patients' bad tolerance or therapeutic compliance. Another cause is an insufficient efficacy of current cholesterol lowering drugs including statins and ezetimibe. In addition, proprotein convertase subtilisin kexin type 9 inhibitors are a new cholesterol lowering medications showing safety and high efficacy to reduce c-LDL in numerous already performed or underway clinical trials, potentially allowing an optimal control of hypercholesterolemia in most patients. Agents inhibiting apolipoprotein B synthesis and microsomal transfer protein are also providing a new potential to decrease cholesterol in patients with severe hypercholesterolemia and in particular in homozygote familial hypercholesterolemia. Last, cholesteryl ester transfer protein inhibitors have shown powerful effects on c-HDL and c-LDL, although their efficacy in cardiovascular prevention and safety has not been demonstrated yet. We provide in this article an overview of the main characteristics of therapeutic agents for hypercholesterolemia, which have been recently approved or in an advanced research stage.

  9. Advances in antithrombotic agents.

    PubMed

    Chakrabarti, Ranjan; Das, Saibal Kumar

    2007-07-01

    Thrombosis is the condition where an imbalance in the homeostatic mechanism results in unwanted intravascular thrombus formation. Imbalances in this highly regulated process of coagulation and anticoagulation can lead to a variety of pathophysiological conditions leading to stroke, pulmonary heart attack and other serious conditions. In the western world, thromboembolic diseases are the leading cause of morbidity and mortality. Remarkable progress has occurred over the last decade in the development of antithrombotic drugs, which can be classified into 3 major categories - Anticoagulants, Antiplatelets and thrombolytics. Increased understanding of the pathobiology of thrombotic and vascular disorders has helped researchers to target novel pathways involving the coagulation, thrombolytic, fibrinolytic and integrin systems. Traditionally aspirin and unfractionated heparin was used for myocardial infarction. Newer antiplatelet agents such as, clopidogrel, GP IIb/IIIa inhibitors, low molecular weight heparin, direct thrombin inhibitors and several improved thrombolytic agents have been introduced for clinical use. This review will discuss different important drugs, which have been launched in recent years and also some new targets pursued by different companies. PMID:17630943

  10. Anaplasma marginale and Theileria annulata in questing ticks from Portugal.

    PubMed

    Antunes, S; Ferrolho, J; Domingues, N; Santos, A S; Santos-Silva, M M; Domingos, A

    2016-09-01

    Ticks are ubiquitous arthropods and vectors of several pathogenic agents in animals and humans. Monitoring questing ticks is of great importance to ascertain the occurrence of pathogens and the potential vector species, offering an insight into the risk of disease transmission in a given area. In this study 428 host-seeking ticks, belonging to nine species of Ixodidae and collected from 17 of the 23 Portuguese mainland subregions, were screened for several tick-borne agents with veterinary relevance: Anaplasma marginale, Anaplasma ovis, Anaplasma centrale, Babesia spp., Coxiella burnetii and Theileria spp. Prevalence was assessed by PCR and amplified amplicons sequenced for validation of results. Twenty ticks, in a total of 428, were found positive: one Ixodes ventalloi for Theileria annulata and four Dermacentor marginatus, one Haemaphysalis punctata, five Ixodes ricinus, five I. ventalloi, and four Rhipicephalus sanguineus sensu lato for A. marginale. According to the reviewed literature, this is the first report of A. marginale and T. annulata detection in I. ventalloi. Furthermore, the amplification of A. marginale DNA in several tick species suggests a broad range for this agent in Portugal that might include other uncommon species as R. sanguineus s.l. This work provides new data towards a better understanding of tick-pathogen associations and also contributes to the surveillance of tick-borne agents in geographic areas with limited information. PMID:27394441

  11. Flexible, secure agent development framework

    DOEpatents

    Goldsmith; Steven Y.

    2009-04-07

    While an agent generator is generating an intelligent agent, it can also evaluate the data processing platform on which it is executing, in order to assess a risk factor associated with operation of the agent generator on the data processing platform. The agent generator can retrieve from a location external to the data processing platform an open site that is configurable by the user, and load the open site into an agent substrate, thereby creating a development agent with code development capabilities. While an intelligent agent is executing a functional program on a data processing platform, it can also evaluate the data processing platform to assess a risk factor associated with performing the data processing function on the data processing platform.

  12. Seroepidemiologic study of three zoonoses (leptospirosis, Q fever, and tularemia) among trappers in Québec, Canada.

    PubMed Central

    Lévesque, B; De Serres, G; Higgins, R; D'Halewyn, M A; Artsob, H; Grondin, J; Major, M; Garvie, M; Duval, B

    1995-01-01

    This study was undertaken to evaluate the prevalence of antibodies against Francisella tularensis, Coxiella burnetii, and certain serovars of Leptospira interrogans among trappers in Québec, Canada. Muskrat trapping was identified as a risk factor for F. tularensis infection, whereas having a cat at home apparently protected trappers against infection by L. interrogans. High percentages of control sera were positive for antibodies against C. burnetii (15%) and L. interrogans (5%), most frequently serovar bratislava. This is the first report of human infection by serovar bratislava in North America. PMID:7583933

  13. Fluoroquinolone antimicrobial agents.

    PubMed Central

    Wolfson, J S; Hooper, D C

    1989-01-01

    The fluoroquinolones, a new class of potent orally absorbed antimicrobial agents, are reviewed, considering structure, mechanisms of action and resistance, spectrum, variables affecting activity in vitro, pharmacokinetic properties, clinical efficacy, emergence of resistance, and tolerability. The primary bacterial target is the enzyme deoxyribonucleic acid gyrase. Bacterial resistance occurs by chromosomal mutations altering deoxyribonucleic acid gyrase and decreasing drug permeation. The drugs are bactericidal and potent in vitro against members of the family Enterobacteriaceae, Haemophilus spp., and Neisseria spp., have good activity against Pseudomonas aeruginosa and staphylococci, and (with several exceptions) are less potent against streptococci and have fair to poor activity against anaerobic species. Potency in vitro decreases in the presence of low pH, magnesium ions, or urine but is little affected by different media, increased inoculum, or serum. The effects of the drugs in combination with a beta-lactam or aminoglycoside are often additive, occasionally synergistic, and rarely antagonistic. The agents are orally absorbed, require at most twice-daily dosing, and achieve high concentrations in urine, feces, and kidney and good concentrations in lung, bone, prostate, and other tissues. The drugs are efficacious in treatment of a variety of bacterial infections, including uncomplicated and complicated urinary tract infections, bacterial gastroenteritis, and gonorrhea, and show promise for therapy of prostatitis, respiratory tract infections, osteomyelitis, and cutaneous infections, particularly when caused by aerobic gram-negative bacilli. Fluoroquinolones have also proved to be efficacious for prophylaxis against travelers' diarrhea and infection with gram-negative bacilli in neutropenic patients. The drugs are effective in eliminating carriage of Neisseria meningitidis. Patient tolerability appears acceptable, with gastrointestinal or central nervous

  14. Biological agents and pregnancy.

    PubMed

    Ekblad, U

    1995-08-01

    Pregnant women are exposed to many biological, eg microbial, agents, which are potentially harmful to the fetus. The reported rates of vertical transmission of hepatitis B and human immunodeficiency virus vary between 3 to 90% and 0 to 65%, respectively. The susceptibility to hepatitis B and human immunodeficiency infection is increased in pregnant physicians, midwives, and nurses because of the bloodborne nature of these viruses. Also, TORCH (toxoplasmosis-rubella-cytomegalovirus-herpes) infections, acquired during pregnancy, may result in congenital infection, and serious sequelae in the neonatal period or years after birth. Schoolteachers and daycare personnel have an increased risk of perinatal varicella, "fifth disease," and mumps. Perinatal listeriosis affects one in 20,000 births and may result in fetal wastage. Because of the risk of the possibility of vertical transmission, immunization during pregnancy with live virus vaccines is not recommended. PMID:8520961

  15. Arylthiosemicarbazones as antileishmanial agents.

    PubMed

    Manzano, José Ignacio; Cochet, Florent; Boucherle, Benjamin; Gómez-Pérez, Verónica; Boumendjel, Ahcène; Gamarro, Francisco; Peuchmaur, Marine

    2016-11-10

    Based on a screening process, we targeted substituted thiosemicarbazone as potential antileishmanial agents. Our objective was to identify the key structural elements contributing to the anti-parasite activity that might be used for development of effective drugs. A series of 32 compounds was synthesized and their efficacy was evaluated against the clinically relevant intracellular amastigotes of Leishmania donovani. From these, 22 compounds showed EC50 values below 10 μM with the most active derivative (compound 14) showing an EC50 of 0.8 μM with very low toxicity on two different mammalian cell lines. The most relevant structural elements required for higher activity indicate that the presence of a fused bicyclic aromatic ring such as a naphthalene bearing an alkyl or an alkoxy group substituent are prerequisites. Owing to the easy synthesis, high activity and low toxicity, the most active compounds could be considered as a lead for further development.

  16. Itch Management: Topical Agents.

    PubMed

    Metz, Martin; Staubach, Petra

    2016-01-01

    Chronic pruritus is a common problem in patients with inflammatory skin diseases as well as in subjects with dry or sensitive skin. Regardless of the underlying cause of the pruritus, a topical therapy is not only useful but most often necessary to achieve symptom control. A good topical therapy should fulfill different functions. An optimal basic therapy based on the condition of the skin is important to repair epithelial barrier defects and to rehydrate the skin. An adequate disease-specific topical therapy is crucial for inflamed skin, e.g. anti-inflammatory topical therapy is an important part in the treatment of atopic dermatitis. Finally, the use of specific antipruritic substances can help to improve pruritus in patients irrespective of the underlying disease. Here, we summarize topical agents used in the treatment of chronic pruritus. PMID:27578070

  17. [Ribonucleases as antiviral agents].

    PubMed

    Il'inskaia, O N; Shakh Makhmud, R

    2014-01-01

    Many ribonucleases (RNases) are able to inhibit the reproduction of viruses in infected cell cultures and laboratory animals, but molecular mechanisms of their antiviral activity remain unclear. The review observes the most known RNases which possess established antiviral effects, actually intracellular RNases (RNase L, MCPIPI protein, eosinophylic RNases) as well as exogenously applied ones (RNase A, BS-RNase, onconase, binase, synthetic RNases). Attention is given on two important but not always obligatory aspects in molecule of RNases, which have antiviral properties: catalytic activity and ability to the dimerization. The hypothetic scheme of virus elimination by exogenous RNases, that reflects possible types of interaction of viruses and RNases with a cell, is proposed. The evidence for RNases as classical components of immune defense which are perspective agents for development of new antiviral therapeutics is produced.

  18. Agent-based enterprise integration

    SciTech Connect

    N. M. Berry; C. M. Pancerella

    1998-12-01

    The authors are developing and deploying software agents in an enterprise information architecture such that the agents manage enterprise resources and facilitate user interaction with these resources. The enterprise agents are built on top of a robust software architecture for data exchange and tool integration across heterogeneous hardware and software. The resulting distributed multi-agent system serves as a method of enhancing enterprises in the following ways: providing users with knowledge about enterprise resources and applications; accessing the dynamically changing enterprise; locating enterprise applications and services; and improving search capabilities for applications and data. Furthermore, agents can access non-agents (i.e., databases and tools) through the enterprise framework. The ultimate target of the effort is the user; they are attempting to increase user productivity in the enterprise. This paper describes their design and early implementation and discusses the planned future work.

  19. Collaborating Fuzzy Reinforcement Learning Agents

    NASA Technical Reports Server (NTRS)

    Berenji, Hamid R.

    1997-01-01

    Earlier, we introduced GARIC-Q, a new method for doing incremental Dynamic Programming using a society of intelligent agents which are controlled at the top level by Fuzzy Relearning and at the local level, each agent learns and operates based on ANTARCTIC, a technique for fuzzy reinforcement learning. In this paper, we show that it is possible for these agents to compete in order to affect the selected control policy but at the same time, they can collaborate while investigating the state space. In this model, the evaluator or the critic learns by observing all the agents behaviors but the control policy changes only based on the behavior of the winning agent also known as the super agent.

  20. [Contact sensitization to external agents].

    PubMed

    Erdmann, S M; Merk, H-F

    2003-04-01

    The following review describes contact sensitization to topically applied medications--especially topical dermatological agents--and to external agents in the broadest sense. Particularly skin care products constitute a special source for sensitization due to their widespread use. Especially fragrances and preservatives in cosmetics play an important global role in eliciting contact allergies. Because of the extremely broad spectrum covered by the active and adjuvant ingredients contained in external agents, the following discussion focuses on specific substance groups.

  1. Broad-spectrum antiviral agents

    PubMed Central

    Zhu, Jun-Da; Meng, Wen; Wang, Xiao-Jia; Wang, Hwa-Chain R.

    2015-01-01

    Development of highly effective, broad-spectrum antiviral agents is the major objective shared by the fields of virology and pharmaceutics. Antiviral drug development has focused on targeting viral entry and replication, as well as modulating cellular defense system. High throughput screening of molecules, genetic engineering of peptides, and functional screening of agents have identified promising candidates for development of optimal broad-spectrum antiviral agents to intervene in viral infection and control viral epidemics. This review discusses current knowledge, prospective applications, opportunities, and challenges in the development of broad-spectrum antiviral agents. PMID:26052325

  2. Incorporating BDI Agents into Human-Agent Decision Making Research

    NASA Astrophysics Data System (ADS)

    Kamphorst, Bart; van Wissen, Arlette; Dignum, Virginia

    Artificial agents, people, institutes and societies all have the ability to make decisions. Decision making as a research area therefore involves a broad spectrum of sciences, ranging from Artificial Intelligence to economics to psychology. The Colored Trails (CT) framework is designed to aid researchers in all fields in examining decision making processes. It is developed both to study interaction between multiple actors (humans or software agents) in a dynamic environment, and to study and model the decision making of these actors. However, agents in the current implementation of CT lack the explanatory power to help understand the reasoning processes involved in decision making. The BDI paradigm that has been proposed in the agent research area to describe rational agents, enables the specification of agents that reason in abstract concepts such as beliefs, goals, plans and events. In this paper, we present CTAPL: an extension to CT that allows BDI software agents that are written in the practical agent programming language 2APL to reason about and interact with a CT environment.

  3. Phytonutrients as therapeutic agents.

    PubMed

    Gupta, Charu; Prakash, Dhan

    2014-09-01

    Nutrients present in various foods plays an important role in maintaining the normal functions of the human body. The major nutrients present in foods include carbohydrates, proteins, lipids, vitamins, and minerals. Besides these, there are some bioactive food components known as "phytonutrients" that play an important role in human health. They have tremendous impact on the health care system and may provide medical health benefits including the prevention and/or treatment of disease and various physiological disorders. Phytonutrients play a positive role by maintaining and modulating immune function to prevent specific diseases. Being natural products, they hold a great promise in clinical therapy as they possess no side effects that are usually associated with chemotherapy or radiotherapy. They are also comparatively cheap and thus significantly reduce health care cost. Phytonutrients are the plant nutrients with specific biological activities that support human health. Some of the important bioactive phytonutrients include polyphenols, terpenoids, resveratrol, flavonoids, isoflavonoids, carotenoids, limonoids, glucosinolates, phytoestrogens, phytosterols, anthocyanins, ω-3 fatty acids, and probiotics. They play specific pharmacological effects in human health such as anti-microbial, anti-oxidants, anti-inflammatory, antiallergic, anti-spasmodic, anti-cancer, anti-aging, hepatoprotective, hypolipidemic, neuroprotective, hypotensive, diabetes, osteoporosis, CNS stimulant, analgesic, protection from UVB-induced carcinogenesis, immuno-modulator, and carminative. This mini-review attempts to summarize the major important types of phytonutrients and their role in promoting human health and as therapeutic agents along with the current market trend and commercialization.

  4. Plasmids encoding therapeutic agents

    DOEpatents

    Keener, William K.

    2007-08-07

    Plasmids encoding anti-HIV and anti-anthrax therapeutic agents are disclosed. Plasmid pWKK-500 encodes a fusion protein containing DP178 as a targeting moiety, the ricin A chain, an HIV protease cleavable linker, and a truncated ricin B chain. N-terminal extensions of the fusion protein include the maltose binding protein and a Factor Xa protease site. C-terminal extensions include a hydrophobic linker, an L domain motif peptide, a KDEL ER retention signal, another Factor Xa protease site, an out-of-frame buforin II coding sequence, the lacZ.alpha. peptide, and a polyhistidine tag. More than twenty derivatives of plasmid pWKK-500 are described. Plasmids pWKK-700 and pWKK-800 are similar to pWKK-500 wherein the DP178-encoding sequence is substituted by RANTES- and SDF-1-encoding sequences, respectively. Plasmid pWKK-900 is similar to pWKK-500 wherein the HIV protease cleavable linker is substituted by a lethal factor (LF) peptide-cleavable linker.

  5. TACtic- A Multi Behavioral Agent for Trading Agent Competition

    NASA Astrophysics Data System (ADS)

    Khosravi, Hassan; Shiri, Mohammad E.; Khosravi, Hamid; Iranmanesh, Ehsan; Davoodi, Alireza

    Software agents are increasingly being used to represent humans in online auctions. Such agents have the advantages of being able to systematically monitor a wide variety of auctions and then make rapid decisions about what bids to place in what auctions. They can do this continuously and repetitively without losing concentration. To provide a means of evaluating and comparing (benchmarking) research methods in this area the trading agent competition (TAC) was established. This paper describes the design, of TACtic. Our agent uses multi behavioral techniques at the heart of its decision making to make bidding decisions in the face of uncertainty, to make predictions about the likely outcomes of auctions, and to alter the agent's bidding strategy in response to the prevailing market conditions.

  6. First report of Babesia gibsoni in Central America and survey for vector-borne infections in dogs from Nicaragua

    PubMed Central

    2014-01-01

    Background Although many vector-borne diseases are important causes of morbidity and mortality in dogs in tropical areas and potential zoonoses, there is little information on these conditions in Central America. Methods Seven qPCRs for vector-borne pathogens were performed on a Roche LightCycler PCR Instrument to investigate their prevalence in a convenience sample of whole blood samples from apparently healthy dogs in Nicaragua. Also, a qPCR targeting the canine hydroxymethylbilane synthase (HMBS) gene was used as an endogenous internal control and verified the quality and quantity of DNA in the samples was appropriate for the study. Results We found DNA of Rickettsia felis (5%), Babesia spp. (26%), Hepatozoon canis (51%), Anaplasma platys (13%) and Ehrlichia canis (56%) in the 39 dogs studied. The qPCRs for Coxiella burnetii and Dirofilaria immitis were negative. Of the 30 (80%) dogs that were positive by qPCR, 12 (31%) were positive for one agent, 11 (28%) for two, 3 (8%) for three, and 4 (10%) for four agents. Conclusions This is the first report of B. gibsoni in dogs from Central America and the first recording of vector-borne agents in dogs from Nicaragua. Dogs in Nicaragua are commonly infected with a variety of vector-borne pathogens, some of which may also infect people. PMID:24667065

  7. Hypersensitivity to antineoplastic agents.

    PubMed

    Castells, M C

    2008-01-01

    The need to offer first line therapy for primary and recurrent cancers has spurred the clinical development of rapid desensitizations for chemotherapy and monoclonal antibodies. Rapid desensitizations allow patients to be treated with medications to which they have presented with hypersensitivity reactions (HSRs), including anaphylaxis. Rapid desensitization achieves temporary tolerization to full therapeutic doses by slow administration of incremental doses of the drug inducing the HSR. Protocols are available for most chemotherapy agents, including taxanes, platins, doxorubicin, monoclonal antibodies, and others. Candidate patients include those who present with type I HSRs, mast cell/IgE dependent, including anaphylaxis, and non-IgE mediated HSRs, during the chemotherapy infusion or shortly after. Idiosyncratic reactions, erythema multiforme, Stevens-Johnson syndrome and toxic epidermal necrolysis are not amenable to rapid desensitization. The recommendation for rapid desensitization can only be made by allergy and immunology specialists and can only be performed in settings with one-to-one nurse-patient care and where resuscitation personnel and resources are readily available. Repeated desensitizations can be safely performed in outpatient settings with similar conditions, which allow cancer patients to remain in clinical studies. We have generated a universal 12-step protocol that was applied to 413 cases of intravenous and intraperitoneal rapid desensitizations using taxanes, platins, liposomal doxorubicin, doxorubicin, rituximab, and other chemotherapy drugs. Under this protocol all patients were able to complete their target dose, and 94% of the patients had limited or no reactions. No deaths or codes were reported, indicating that the procedure was safe and effective in delivering first line chemotherapy drugs. PMID:18991707

  8. Agent-Based Literacy Theory

    ERIC Educational Resources Information Center

    McEneaney, John E.

    2006-01-01

    The purpose of this theoretical essay is to explore the limits of traditional conceptualizations of reader and text and to propose a more general theory based on the concept of a literacy agent. The proposed theoretical perspective subsumes concepts from traditional theory and aims to account for literacy online. The agent-based literacy theory…

  9. Gelled Anti-icing Agents

    NASA Technical Reports Server (NTRS)

    Markles, O. F.; Sperber, H. H.

    1983-01-01

    Pectin added to antifreeze/water mixture. Formulations include water with dimethyl sulfoxide (DMSO) as deicer and pectin as gel former. Without gelling agent, deicer runs off vertical surfaces. Without pectin solution will completely evaporate in far less time. Agents developed have wide potential for ice prevention on runways, highways, bridges and sidewalks.

  10. Seroprevalence of infectious diseases in saiga antelope (Saiga tatarica tatarica) in Kazakhstan 2012-2014.

    PubMed

    Orynbayev, Mukhit B; Beauvais, Wendy; Sansyzbay, Abylay R; Rystaeva, Rashida A; Sultankulova, Kulyaisan T; Kerimbaev, Aslan A; Kospanova, Madina N; Kock, Richard A

    2016-05-01

    286 serum samples were collected from three sub-populations of saiga in Kazakhstan (Betpakdala, Ustyurt and Volga-Ural) between 2012 and 2014, and were tested for the presence of antibodies to Brucella spp., bluetongue virus, peste des petits ruminants (PPR) virus, Akabane virus, Schmallenberg virus, Chlamydophila, Toxoplasma, Mycobacterium avium subspecies paratuberculosis and Coxiella burnetii (Q Fever). Seropositives to Coxiella burnetii of saiga were detected and the adjusted seroprevalence of Q Fever antibodies was 0.07 (95% confidence interval (CI): 0.03-0.10). Seropositives to Akabane virus were detected in all three populations and the adjusted seroprevalence values for this virus were very high (all were>0.13). Lower adjusted seroprevalence values were estimated for PPR Virus and Mycobacterium avium subsp. paratuberculosis (0.005 and 0.006). No seropositives for bluetongue, Toxoplasma, Brucella or Schmallenberg were detected. PMID:27094147

  11. [Q Fever in Tunisia].

    PubMed

    Kaabia, N; Letaief, A

    2009-07-01

    Q fever is a common zoonosis with almost a worldwide distribution caused by Coxiella burnetii. Farm animals and pets are the main reservoirs of infection and transmission to humans is usually via inhalation of contaminated aerosols. Infection in humans is often asymptomatic, but it can manifest as an acute disease (usually a self-limited flu-like illness, pneumonia or hepatitis) or as a chronic form (mainly endocarditis, but also hepatitis and chronic-fatigue syndrome). In Tunisia, although prevalence of anti-Coxiella burnetii was high among blood donors, Q fever was rarely reported and frequently miss diagnosed by physicians. This study is a review of epidemiological and clinical particularities of Q fever in Tunisia.

  12. Dialogue Games for Agent Argumentation

    NASA Astrophysics Data System (ADS)

    McBurney, Peter; Parsons, Simon

    The rise of the Internet and the growth of distributed computing have led to a major paradigm shift in software engineering and computer science. Until recently, the notion of computation has been variously construed as numerical calculation, as information processing, or as intelligent symbol analysis, but increasingly, it is now viewed as distributed cognition and interaction between intelligent entities [60]. This new view has major implications for the conceptualization, design, engineering and control of software systems, most profoundly expressed in the concept of systems of intelligent software agents, or multi-agent systems [99]. Agents are software entities with control over their own execution; the design of such agents, and of multi-agent systems of them, presents major research and software engineering challenges to computer scientists.

  13. Intelligent Agents in Physics Education

    NASA Astrophysics Data System (ADS)

    Sánchez-Guzmán, D.; Mora, César

    2010-07-01

    Intelligent Agents are being applied in a wide range of processes and everyday applications. Their development is not new, in recent years they have had an increased attention and design; like learning and mentoring tools. In this work we discuss the definition of what an intelligent agent is; how they are applied; how they look like; recent implementations of agents; agents as support in the learning process, more precisely intelligent tutors; their state in Latin-American countries and future developments and trends that will permit a better communication between people and agents. Also we present an Intelligent Tutor applied as a tool for improving high-school students' skills and reasoning for the first five topics of Mechanics curricula.

  14. Transdermal delivery of therapeutic agent

    NASA Technical Reports Server (NTRS)

    Kwiatkowski, Krzysztof C. (Inventor); Hayes, Ryan T. (Inventor); Magnuson, James W. (Inventor); Giletto, Anthony (Inventor)

    2008-01-01

    A device for the transdermal delivery of a therapeutic agent to a biological subject that includes a first electrode comprising a first array of electrically conductive microprojections for providing electrical communication through a skin portion of the subject to a second electrode comprising a second array of electrically conductive microprojections. Additionally, a reservoir for holding the therapeutic agent surrounding the first electrode and a pulse generator for providing an exponential decay pulse between the first and second electrodes may be provided. A method includes the steps of piercing a stratum corneum layer of skin with two arrays of conductive microprojections, encapsulating the therapeutic agent into biocompatible charged carriers, surrounding the conductive microprojections with the therapeutic agent, generating an exponential decay pulse between the two arrays of conductive microprojections to create a non-uniform electrical field and electrokinetically driving the therapeutic agent through the stratum corneum layer of skin.

  15. Markov Tracking for Agent Coordination

    NASA Technical Reports Server (NTRS)

    Washington, Richard; Lau, Sonie (Technical Monitor)

    1998-01-01

    Partially observable Markov decision processes (POMDPs) axe an attractive representation for representing agent behavior, since they capture uncertainty in both the agent's state and its actions. However, finding an optimal policy for POMDPs in general is computationally difficult. In this paper we present Markov Tracking, a restricted problem of coordinating actions with an agent or process represented as a POMDP Because the actions coordinate with the agent rather than influence its behavior, the optimal solution to this problem can be computed locally and quickly. We also demonstrate the use of the technique on sequential POMDPs, which can be used to model a behavior that follows a linear, acyclic trajectory through a series of states. By imposing a "windowing" restriction that restricts the number of possible alternatives considered at any moment to a fixed size, a coordinating action can be calculated in constant time, making this amenable to coordination with complex agents.

  16. Knowledge focus via software agents

    NASA Astrophysics Data System (ADS)

    Henager, Donald E.

    2001-09-01

    The essence of military Command and Control (C2) is making knowledge intensive decisions in a limited amount of time using uncertain, incorrect, or outdated information. It is essential to provide tools to decision-makers that provide: * Management of friendly forces by treating the "friendly resources as a system". * Rapid assessment of effects of military actions againt the "enemy as a system". * Assessment of how an enemy should, can, and could react to friendly military activities. Software agents in the form of mission agents, target agents, maintenance agents, and logistics agents can meet this information challenge. The role of each agent is to know all the details about its assigned mission, target, maintenance, or logistics entity. The Mission Agent would fight for mission resources based on the mission priority and analyze the effect that a proposed mission's results would have on the enemy. The Target Agent (TA) communicates with other targets to determine its role in the system of targets. A system of TAs would be able to inform a planner or analyst of the status of a system of targets, the effect of that status, adn the effect of attacks on that system. The system of TAs would also be able to analyze possible enemy reactions to attack by determining ways to minimize the effect of attack, such as rerouting traffic or using deception. The Maintenance Agent would scheudle maintenance events and notify the maintenance unit. The Logistics Agent would manage shipment and delivery of supplies to maintain appropriate levels of weapons, fuel and spare parts. The central idea underlying this case of software agents is knowledge focus. Software agents are createad automatically to focus their attention on individual real-world entities (e.g., missions, targets) and view the world from that entities perspective. The agent autonomously monitors the entity, identifies problems/opportunities, formulates solutions, and informs the decision-maker. The agent must be

  17. Contrast agents for cardiac angiography: effects of a nonionic agent vs. a standard ionic agent

    SciTech Connect

    Bettmann, M.A.; Bourdillon, P.D.; Barry, W.H.; Brush, K.A.; Levin, D.C.

    1984-12-01

    The effects on cardiac hemodynamics and of a standard contrast agent, sodium methylglucamine diatrizoate (Renografin 76) were compared with the effects of a new nonionic agent (iohexol) in a double-blind study in 51 patietns undergoing coronary angiography and left ventriculography. No significant alteration in measured blood parameters occurred with either contrast agent. Hemodynamic changes occurred with both, but were significantly greater with the standard renografin than with the low-osmolality, nonionic iohexol. After left ventriculography, heart rate increased and peripheral arterial pressure fell with both agents, but less with iohexol. It is concluded that iohexol causes less alteration in cardiac function than does the agent currently most widely used. Nonionic contrast material is likely to improve the safety of coronary angiography, particularly in those patients at greatest risk.

  18. Q Fever, Scrub Typhus, and Rickettsial Diseases in Children, Kenya, 2011–2012

    PubMed Central

    Farris, Christina M.; Odhiambo, Antony; Jiang, Ju; Laktabai, Jeremiah; Armstrong, Janice; Holland, Thomas; Richards, Allen L.; O’Meara, Wendy P.

    2016-01-01

    To increase knowledge of undifferentiated fevers in Kenya, we tested paired serum samples from febrile children in western Kenya for antibodies against pathogens increasingly recognized to cause febrile illness in Africa. Of patients assessed, 8.9%, 22.4%, 1.1%, and 3.6% had enhanced seroreactivity to Coxiella burnetii, spotted fever group rickettsiae, typhus group rickettsiae, and scrub typhus group orientiae, respectively. PMID:27088502

  19. Q Fever, Scrub Typhus, and Rickettsial Diseases in Children, Kenya, 2011-2012.

    PubMed

    Maina, Alice N; Farris, Christina M; Odhiambo, Antony; Jiang, Ju; Laktabai, Jeremiah; Armstrong, Janice; Holland, Thomas; Richards, Allen L; O'Meara, Wendy P

    2016-05-01

    To increase knowledge of undifferentiated fevers in Kenya, we tested paired serum samples from febrile children in western Kenya for antibodies against pathogens increasingly recognized to cause febrile illness in Africa. Of patients assessed, 8.9%, 22.4%, 1.1%, and 3.6% had enhanced seroreactivity to Coxiella burnetii, spotted fever group rickettsiae, typhus group rickettsiae, and scrub typhus group orientiae, respectively. PMID:27088502

  20. Agent Communications using Distributed Metaobjects

    SciTech Connect

    Goldsmith, Steven Y.; Spires, Shannon V.

    1999-06-10

    There are currently two proposed standards for agent communication languages, namely, KQML (Finin, Lobrou, and Mayfield 1994) and the FIPA ACL. Neither standard has yet achieved primacy, and neither has been evaluated extensively in an open environment such as the Internet. It seems prudent therefore to design a general-purpose agent communications facility for new agent architectures that is flexible yet provides an architecture that accepts many different specializations. In this paper we exhibit the salient features of an agent communications architecture based on distributed metaobjects. This architecture captures design commitments at a metaobject level, leaving the base-level design and implementation up to the agent developer. The scope of the metamodel is broad enough to accommodate many different communication protocols, interaction protocols, and knowledge sharing regimes through extensions to the metaobject framework. We conclude that with a powerful distributed object substrate that supports metaobject communications, a general framework can be developed that will effectively enable different approaches to agent communications in the same agent system. We have implemented a KQML-based communications protocol and have several special-purpose interaction protocols under development.

  1. Nuclear magnetic resonance contrast agents

    DOEpatents

    Smith, P.H.; Brainard, J.R.; Jarvinen, G.D.; Ryan, R.R.

    1997-12-30

    A family of contrast agents for use in magnetic resonance imaging and a method of enhancing the contrast of magnetic resonance images of an object by incorporating a contrast agent of this invention into the object prior to forming the images or during formation of the images. A contrast agent of this invention is a paramagnetic lanthanide hexaazamacrocyclic molecule, where a basic example has the formula LnC{sub 16}H{sub 14}N{sub 6}. Important applications of the invention are in medical diagnosis, treatment, and research, where images of portions of a human body are formed by means of magnetic resonance techniques. 10 figs.

  2. Nuclear magnetic resonance contrast agents

    DOEpatents

    Smith, Paul H.; Brainard, James R.; Jarvinen, Gordon D.; Ryan, Robert R.

    1997-01-01

    A family of contrast agents for use in magnetic resonance imaging and a method of enhancing the contrast of magnetic resonance images of an object by incorporating a contrast agent of this invention into the object prior to forming the images or during formation of the images. A contrast agent of this invention is a paramagnetic lanthanide hexaazamacrocyclic molecule, where a basic example has the formula LnC.sub.16 H.sub.14 N.sub.6. Important applications of the invention are in medical diagnosis, treatment, and research, where images of portions of a human body are formed by means of magnetic resonance techniques.

  3. Antibacterial agents in the cinema.

    PubMed

    García Sánchez, J E; García Sánchez, E; Merino Marcos, M L

    2006-12-01

    Numerous procedures used as antibacterial therapy are present in many films and include strategies ranging from different antimicrobial drugs to surgery and supporting measures. Films also explore the correct use and misuse of antimicrobial agents. Side effects and other aspects related to antibacterial therapy have also been reflected in some films. This article refers to the presence of antibacterial agents in different popular movies. There are movies in which antibacterial agents form part of the central plot, while in others it is merely an important part of the plot. In still others, its presence is isolated, and in these it plays an ambient or anecdotal role.

  4. Provocative agents in panic disorder.

    PubMed

    Bourin, M; Malinge, M; Guitton, B

    1995-01-01

    The pharmacological challenge strategy involves giving a provoking agent under controlled rules to clarify some aspect of behavioural or biological function. Various agents such as sodium lactate, carbon dioxide, caffeine, yohimbine, isoprenaline and now cholecystokinin have been used as provoking agents in healthy volunteers as well as in panic patients. Results obtained in this field are updated, with emphasis on the potential mechanisms of action. It is concluded that there may be a final pathway between carbon dioxide, sodium lactate, and cholecystokinin inducing panic attacks.

  5. Agent-based forward analysis

    SciTech Connect

    Kerekes, Ryan A.; Jiao, Yu; Shankar, Mallikarjun; Potok, Thomas E.; Lusk, Rick M.

    2008-01-01

    We propose software agent-based "forward analysis" for efficient information retrieval in a network of sensing devices. In our approach, processing is pushed to the data at the edge of the network via intelligent software agents rather than pulling data to a central facility for processing. The agents are deployed with a specific query and perform varying levels of analysis of the data, communicating with each other and sending only relevant information back across the network. We demonstrate our concept in the context of face recognition using a wireless test bed comprised of PDA cell phones and laptops. We show that agent-based forward analysis can provide a significant increase in retrieval speed while decreasing bandwidth usage and information overload at the central facility. n

  6. Triggered pore-forming agents

    DOEpatents

    Bayley, Hagan; Walker, Barbara J.; Chang, Chung-yu; Niblack, Brett; Panchal, Rekha

    1998-01-01

    An inactive pore-forming agent which is activated to lytic function by a condition such as pH, light, heat, reducing potential, or metal ion concentration, or substance such as a protease, at the surface of a cell.

  7. AL Amyloidosis and Agent Orange

    MedlinePlus

    ... for survivors' benefits . Research on AL amyloidosis and herbicides The Health and Medicine Division (formally known as ... to the compounds of interest found in the herbicide Agent Orange and AL amyloidosis." VA made a ...

  8. Diamine curing agents for polyurethanes

    NASA Technical Reports Server (NTRS)

    Bell, V. L.; St. Clair, T. L.

    1975-01-01

    Three aromatic diamines have properties that make them promising candidates as curing agents for converting isocyanates to polyurethanes with higher adhesive strengths, higher softening temperatures, better toughness, and improved abrasion resistance.

  9. Launch Commit Criteria Monitoring Agent

    NASA Technical Reports Server (NTRS)

    Semmel, Glenn S.; Davis, Steven R.; Leucht, Kurt W.; Rowe, Dan A.; Kelly, Andrew O.; Boeloeni, Ladislau

    2005-01-01

    The Spaceport Processing Systems Branch at NASA Kennedy Space Center has developed and deployed a software agent to monitor the Space Shuttle's ground processing telemetry stream. The application, the Launch Commit Criteria Monitoring Agent, increases situational awareness for system and hardware engineers during Shuttle launch countdown. The agent provides autonomous monitoring of the telemetry stream, automatically alerts system engineers when predefined criteria have been met, identifies limit warnings and violations of launch commit criteria, aids Shuttle engineers through troubleshooting procedures, and provides additional insight to verify appropriate troubleshooting of problems by contractors. The agent has successfully detected launch commit criteria warnings and violations on a simulated playback data stream. Efficiency and safety are improved through increased automation.

  10. Noncontraceptive use of contraceptive agents.

    PubMed

    Nickles, Monique Collier; Alderman, Elizabeth

    2014-06-01

    • On the basis of strong research evidence, there are many noncontraceptive advantages to use of hormonal contraceptive agents in adolescent girls. (3) (4)(5)(7)(10)(11)(12)(13)(14). • On the basis of research evidence and consensus, most of these agents are safe with minor adverse effects. (2)(3)(4)(5)(7)(10)(11)(12)(13)(14). • On the basis of research evidence and consensus, through application of evidence-based approaches and proper counseling, pediatricians can use various contraceptive agents to treat several medical conditions and to help alleviate many of the undesired symptoms and complications associated with menstrual periods. (2)(3)(4)(5)(7)(10)(11)(12)(13) (14). • On the basis of research evidence and consensus, these agents may be used in sexually active adolescents to simultaneously help prevent unintended adolescent pregnancies. (2)(3)(4)(5)(7)(10)(11)(12)(13)(14).

  11. Antimicrobials for bacterial bioterrorism agents.

    PubMed

    Sarkar-Tyson, Mitali; Atkins, Helen S

    2011-06-01

    The limitations of current antimicrobials for highly virulent pathogens considered as potential bioterrorism agents drives the requirement for new antimicrobials that are suitable for use in populations in the event of a deliberate release. Strategies targeting bacterial virulence offer the potential for new countermeasures to combat bacterial bioterrorism agents, including those active against a broad spectrum of pathogens. Although early in the development of antivirulence approaches, inhibitors of bacterial type III secretion systems and cell division mechanisms show promise for the future.

  12. Ramucirumab: a novel antiangiogenic agent.

    PubMed

    Wadhwa, Roopma; Taketa, Takashi; Sudo, Kazuki; Blum-Murphy, Mariela; Ajani, Jaffer A

    2013-06-01

    Ramucirumab (IMC-1121B) is a fully humanized monoclonal antibody that binds to VEGFR2 and can inhibit angiogenesis, a quintessential mechanism for promoting tumor growth and metastasis. Several antiangiogenesis agents are already approved for cancer therapy; however, ramucirumab's selectivity for VEGFR2 makes it interesting. The selectivity of an agent can improve safety and efficacy. This article describes the mechanism of action, pharmacokinetics, safety and clinical trial results of ramucirumab with particular emphasis on gastric cancer.

  13. Community-based prevalence profile of arboviral, rickettsial, and Hantaan-like viral antibody in the Nile River Delta of Egypt.

    PubMed

    Corwin, A; Habib, M; Watts, D; Darwish, M; Olson, J; Botros, B; Hibbs, R; Kleinosky, M; Lee, H W; Shope, R

    1993-06-01

    To determine the current prevalence of antibody to arboviruses, rickettsiae, and hantaan-like viruses, a survey was carried out in the Nile River Valley of Egypt, one of the principal foci of the 1977-1978 Rift Valley fever (RVF) outbreak. Blood specimens were obtained from 915 persons representing 190 study households. Enzyme immunoassay testing showed that the overall prevalence of IgG antibody was 4% to sand fly fever Sicilian (SFS), 2% to sandfly fever Naples (SFN), 15% to RVF, 20% to West Nile, and 4% to Hantaan (HTN) viruses. Antibody was demonstrated among 32% of the same study subjects to Coxiella burnetii, 58% to Rickettsia typhi, and 32% to R. conorii. The prevalence of agent-specific antibody tended to increase with age. Particularly notable was the low prevalence of RVF infection in children born after the height of the RVF outbreak. No detectable antibodies were found in the population less than seven years of age and in only 3% of those 7-12 years old. In contrast, 26% of the study population 13-19 years old, who were young children and infants at the time of the outbreak, were found to have RVF antibodies, suggesting that the level of intensity associated with transmission decreased considerably following the documented 1977-1978 outbreak. Geometric mean titers (GMT) ranged from 139 for C. burnetii to 1,305 for RVF, and did not vary significantly by age, except for high titers for RVF in the 20-49-year-old age group. A significant upward trend in GMT was also noted when antibody was detected in the specimen for more than one phlebovirus.(ABSTRACT TRUNCATED AT 250 WORDS)

  14. Natural products as antimitotic agents.

    PubMed

    Dall'Acqua, Stefano

    2014-01-01

    Natural products still play an important role in the medicinal chemistry, especially in some therapeutic areas. As example more than 60% of currently-used anticancer agents are derives from natural sources including plants, marine organisms or micro-organism. Thus natural products (NP) are an high-impact source of new "lead compounds" or new potential therapeutic agents despite the large development of biotechnology and combinatorial chemistry in the drug discovery and development. Many examples of anticancer drugs as paclitaxel, combretastatin, bryostatin and discodermolide have shown the importance of NP in the anticancer chemotherapy through many years. Many organisms have been studied as sources of drugs namely plants, micro-organisms and marine organisms and the obtained NP can be considered a group of "privileged chemical structures" evolved in nature to interact with other organisms. For this reason NP are a good starting points for pharmaceutical research and also for library design. Tubulin and microtubules are one of the most studied targets for the search of anticancer compounds. Microtubule targeting agents (MTA) also named antimitotic agents are compounds that are able to perturb mitosis but are also able to arrest cell growing during interphase. The anticancer drugs, taxanes and vinca alkaloids have established tubulin as important target in cancer therapy. More recently the vascular disrupting agents (VDA) combretastatin analogues were studied for their antimitotics properties. This review will consider the anti mitotic NP and their potential impact in the development of new therapeutic agents.

  15. What makes virtual agents believable?

    NASA Astrophysics Data System (ADS)

    Bogdanovych, Anton; Trescak, Tomas; Simoff, Simeon

    2016-01-01

    In this paper we investigate the concept of believability and make an attempt to isolate individual characteristics (features) that contribute to making virtual characters believable. As the result of this investigation we have produced a formalisation of believability and based on this formalisation built a computational framework focused on simulation of believable virtual agents that possess the identified features. In order to test whether the identified features are, in fact, responsible for agents being perceived as more believable, we have conducted a user study. In this study we tested user reactions towards the virtual characters that were created for a simulation of aboriginal inhabitants of a particular area of Sydney, Australia in 1770 A.D. The participants of our user study were exposed to short simulated scenes, in which virtual agents performed some behaviour in two different ways (while possessing a certain aspect of believability vs. not possessing it). The results of the study indicate that virtual agents that appear resource bounded, are aware of their environment, own interaction capabilities and their state in the world, agents that can adapt to changes in the environment and exist in correct social context are those that are being perceived as more believable. Further in the paper we discuss these and other believability features and provide a quantitative analysis of the level of contribution for each such feature to the overall perceived believability of a virtual agent.

  16. Endocarditis Due to Rare and Fastidious Bacteria

    PubMed Central

    Brouqui, P.; Raoult, D.

    2001-01-01

    The etiologic diagnosis of infective endocarditis is easily made in the presence of continuous bacteremia with gram-positive cocci. However, the blood culture may contain a bacterium rarely associated with endocarditis, such as Lactobacillus spp., Klebsiella spp., or nontoxigenic Corynebacterium, Salmonella, Gemella, Campylobacter, Aeromonas, Yersinia, Nocardia, Pasteurella, Listeria, or Erysipelothrix spp., that requires further investigation to establish the relationship with endocarditis, or the blood culture may be uninformative despite a supportive clinical evaluation. In the latter case, the etiologic agents are either fastidious extracellular or intracellular bacteria. Fastidious extracellular bacteria such as Abiotrophia, HACEK group bacteria, Clostridium, Brucella, Legionella, Mycobacterium, and Bartonella spp. need supplemented media, prolonged incubation time, and special culture conditions. Intracellular bacteria such as Coxiella burnetii cannot be isolated routinely. The two most prevalent etiologic agents of culture-negative endocarditis are C. burnetti and Bartonella spp. Their diagnosis is usually carried out serologically. A systemic pathologic examination of excised heart valves including periodic acid-Schiff (PAS) staining and molecular methods has allowed the identification of Whipple's bacillus endocarditis. Pathologic examination of the valve using special staining, such as Warthin-Starry, Gimenez, and PAS, and broad-spectrum PCR should be performed systematically when no etiologic diagnosis is evident through routine laboratory evaluation. PMID:11148009

  17. Ectoparasites and associated pathogens of free-roaming and captive animals in zoos of South Carolina.

    PubMed

    Nelder, Mark P; Reeves, Will K; Adler, Peter H; Wozniak, Arthur; Wills, William

    2009-10-01

    A survey of ectoparasites and their associated pathogens was conducted in two South Carolina zoos, from 2004 to 2007. Dead, wild birds and mammals, as well as captive animals examined during routine veterinary checks constituted the study populations. Ectoparasites were tested for species of Anaplasma, Bartonella, Coxiella burnetii, Ehrlichia, Rickettsia, and Trypanosoma. Forty-six species of ectoparasites were collected from 133 free-roaming and captive hosts and their associated nesting and bedding materials. Six vector-borne pathogens were detected molecularly in the ectoparasites, including Anaplasma phagocytophilum in the tick Ixodes dentatus Marx from an eastern cottontail rabbit, Bartonella clarridgeiae in the cat flea Ctenocephalides felis (Bouché) from a Virginia opossum, Bartonella sp. Oh6 in the squirrel flea Orchopeas howardi (Baker) from an eastern grey squirrel, Bartonella sp. T7498 in the sucking louse Neohaematopinus sciuri Jancke from a squirrel, Rickettsia sp. Rf2125 in C. felis from a zookeeper and a grizzly bear, and Rickettsiales sp. Ib 2006 in Ixodes brunneus Koch from an American crow. While the pathology of some of these pathogens is poorly known, Anaplasma phagocytophilum (causative agent of human granulocytic anaplasmosis) and Bartonella clarridgeiae (causative agent of a disease similar to cat-scratch disease) can infect humans. Ectoparasites and their pathogens, especially those originating from free-roaming animals, present a potential threat to captive animals and humans.

  18. Ectoparasites and associated pathogens of free-roaming and captive animals in zoos of South Carolina.

    PubMed

    Nelder, Mark P; Reeves, Will K; Adler, Peter H; Wozniak, Arthur; Wills, William

    2009-10-01

    A survey of ectoparasites and their associated pathogens was conducted in two South Carolina zoos, from 2004 to 2007. Dead, wild birds and mammals, as well as captive animals examined during routine veterinary checks constituted the study populations. Ectoparasites were tested for species of Anaplasma, Bartonella, Coxiella burnetii, Ehrlichia, Rickettsia, and Trypanosoma. Forty-six species of ectoparasites were collected from 133 free-roaming and captive hosts and their associated nesting and bedding materials. Six vector-borne pathogens were detected molecularly in the ectoparasites, including Anaplasma phagocytophilum in the tick Ixodes dentatus Marx from an eastern cottontail rabbit, Bartonella clarridgeiae in the cat flea Ctenocephalides felis (Bouché) from a Virginia opossum, Bartonella sp. Oh6 in the squirrel flea Orchopeas howardi (Baker) from an eastern grey squirrel, Bartonella sp. T7498 in the sucking louse Neohaematopinus sciuri Jancke from a squirrel, Rickettsia sp. Rf2125 in C. felis from a zookeeper and a grizzly bear, and Rickettsiales sp. Ib 2006 in Ixodes brunneus Koch from an American crow. While the pathology of some of these pathogens is poorly known, Anaplasma phagocytophilum (causative agent of human granulocytic anaplasmosis) and Bartonella clarridgeiae (causative agent of a disease similar to cat-scratch disease) can infect humans. Ectoparasites and their pathogens, especially those originating from free-roaming animals, present a potential threat to captive animals and humans. PMID:18973443

  19. Two rare manifestations of Q fever: splenic and hepatic abscesses and cerebral venous thrombosis, with literature review ma non troppo.

    PubMed

    Gomes, Manuel Mendes; Chaves, Andreia; Gouveia, Ana; Santos, Lèlita

    2014-02-05

    Q fever is a zoonosis caused by Coxiella burnetii. It often manifests as a flu-like syndrome; other common manifestations are pneumonia, hepatitis and endocarditis. Its course may be acute or chronic. The authors present two clinical cases of Q fever with rare manifestations. Case 1: A 55-year-old man admitted due to abdominal pain, diarrhoea and fever. Blood tests showed elevated transaminases, low platelets and elevated C reactive protein, with normal white cell counts; abdominal ultrasound showed splenic and hepatic abscesses. Serologies to C burnetii were positive (1:640), leading to the diagnosis of Q fever with splenic and hepatic abscesses. Case 2: A 47-year-old man admitted due to headache after sneezing, with unstable gait and vertigo. A brain tomography showed cerebral venous thrombosis. After an exhaustive investigation, antibodies to C burnetii were found and were undoubtedly positive (1:5120), leading to the diagnosis of Q fever. Both patients were treated with oral doxycycline.

  20. A multi-agent architecture for geosimulation of moving agents

    NASA Astrophysics Data System (ADS)

    Vahidnia, Mohammad H.; Alesheikh, Ali A.; Alavipanah, Seyed Kazem

    2015-10-01

    In this paper, a novel architecture is proposed in which an axiomatic derivation system in the form of first-order logic facilitates declarative explanation and spatial reasoning. Simulation of environmental perception and interaction between autonomous agents is designed with a geographic belief-desire-intention and a request-inform-query model. The architecture has a complementary quantitative component that supports collaborative planning based on the concept of equilibrium and game theory. This new architecture presents a departure from current best practices geographic agent-based modelling. Implementation tasks are discussed in some detail, as well as scenarios for fleet management and disaster management.

  1. Next Generation Remote Agent Planner

    NASA Technical Reports Server (NTRS)

    Jonsson, Ari K.; Muscettola, Nicola; Morris, Paul H.; Rajan, Kanna

    1999-01-01

    In May 1999, as part of a unique technology validation experiment onboard the Deep Space One spacecraft, the Remote Agent became the first complete autonomous spacecraft control architecture to run as flight software onboard an active spacecraft. As one of the three components of the architecture, the Remote Agent Planner had the task of laying out the course of action to be taken, which included activities such as turning, thrusting, data gathering, and communicating. Building on the successful approach developed for the Remote Agent Planner, the Next Generation Remote Agent Planner is a completely redesigned and reimplemented version of the planner. The new system provides all the key capabilities of the original planner, while adding functionality, improving performance and providing a modular and extendible implementation. The goal of this ongoing project is to develop a system that provides both a basis for future applications and a framework for further research in the area of autonomous planning for spacecraft. In this article, we present an introductory overview of the Next Generation Remote Agent Planner. We present a new and simplified definition of the planning problem, describe the basics of the planning process, lay out the new system design and examine the functionality of the core reasoning module.

  2. Investigational Antimicrobial Agents of 2013

    PubMed Central

    Pucci, Michael J.

    2013-01-01

    SUMMARY New antimicrobial agents are always needed to counteract the resistant pathogens that continue to be selected by current therapeutic regimens. This review provides a survey of known antimicrobial agents that were currently in clinical development in the fall of 2012 and spring of 2013. Data were collected from published literature primarily from 2010 to 2012, meeting abstracts (2011 to 2012), government websites, and company websites when appropriate. Compared to what was reported in previous surveys, a surprising number of new agents are currently in company pipelines, particularly in phase 3 clinical development. Familiar antibacterial classes of the quinolones, tetracyclines, oxazolidinones, glycopeptides, and cephalosporins are represented by entities with enhanced antimicrobial or pharmacological properties. More importantly, compounds of novel chemical structures targeting bacterial pathways not previously exploited are under development. Some of the most promising compounds include novel β-lactamase inhibitor combinations that target many multidrug-resistant Gram-negative bacteria, a critical medical need. Although new antimicrobial agents will continue to be needed to address increasing antibiotic resistance, there are novel agents in development to tackle at least some of the more worrisome pathogens in the current nosocomial setting. PMID:24092856

  3. Relational agents in clinical psychiatry.

    PubMed

    Bickmore, Timothy; Gruber, Amanda

    2010-01-01

    Relational agents are computational artifacts, such as animated, screen-based characters or social robots, that are designed to establish a sense of rapport, trust, and even therapeutic alliance with patients, using ideal therapeutic relationships between human counselors and patients as role models. We describe the development and evaluation of several such agents designed for health counseling and behavioral-change interventions, in which a therapeutic alliance is established with patients in order to enhance the efficacy of the intervention. We also discuss the promise of using such agents as adjuncts to clinical psychiatry, a range of possible applications, and some of the challenges and ethical issues in developing and fielding them in psychiatric interventions.

  4. Haloprogin: a Topical Antifungal Agent

    PubMed Central

    Harrison, E. F.; Zwadyk, P.; Bequette, R. J.; Hamlow, E. E.; Tavormina, P. A.; Zygmunt, W. A.

    1970-01-01

    Haloprogin was shown to be a highly effective agent for the treatment of experimentally induced topical mycotic infections in guinea pigs. Its in vitro spectrum of activity also includes yeasts, yeastlike fungi (Candida species), and certain gram-positive bacteria. The in vitro and in vivo antifungal activity of haloprogin against dermatophytes was equal to that observed with tolnaftate. The striking differences between the two agents were the marked antimonilial and selective antibacterial activities shown by haloprogin, contrasted with the negligible activities found with tolnaftate. Addition of serum decreased the in vitro antifungal activity of haloprogin to a greater extent than that of tolnaftate; however, diminished antifungal activity was not observed when haloprogin was applied topically to experimental dermatophytic infections. Based on its broad spectrum of antimicrobial activity, haloprogin may prove to be a superior topical agent in the treatment of dermatophytic and monilial infections in man. PMID:5422306

  5. Dual Rationality and Deliberative Agents

    NASA Astrophysics Data System (ADS)

    Debenham, John; Sierra, Carles

    Human agents deliberate using models based on reason for only a minute proportion of the decisions that they make. In stark contrast, the deliberation of artificial agents is heavily dominated by formal models based on reason such as game theory, decision theory and logic—despite that fact that formal reasoning will not necessarily lead to superior real-world decisions. Further the Nobel Laureate Friedrich Hayek warns us of the ‘fatal conceit’ in controlling deliberative systems using models based on reason as the particular model chosen will then shape the system’s future and either impede, or eventually destroy, the subtle evolutionary processes that are an integral part of human systems and institutions, and are crucial to their evolution and long-term survival. We describe an architecture for artificial agents that is founded on Hayek’s two rationalities and supports the two forms of deliberation used by mankind.

  6. Polycatechol Nanoparticle MRI Contrast Agents.

    PubMed

    Li, Yiwen; Huang, Yuran; Wang, Zhao; Carniato, Fabio; Xie, Yijun; Patterson, Joseph P; Thompson, Matthew P; Andolina, Christopher M; Ditri, Treffly B; Millstone, Jill E; Figueroa, Joshua S; Rinehart, Jeffrey D; Scadeng, Miriam; Botta, Mauro; Gianneschi, Nathan C

    2016-02-01

    Amphiphilic triblock copolymers containing Fe(III) -catecholate complexes formulated as spherical- or cylindrical-shaped micellar nanoparticles (SMN and CMN, respectively) are described as new T1-weighted agents with high relaxivity, low cytotoxicity, and long-term stability in biological fluids. Relaxivities of both SMN and CMN exceed those of established gadolinium chelates across a wide range of magnetic field strengths. Interestingly, shape-dependent behavior is observed in terms of the particles' interactions with HeLa cells, with CMN exhibiting enhanced uptake and contrast via magnetic resonance imaging (MRI) compared with SMN. These results suggest that control over soft nanoparticle shape will provide an avenue for optimization of particle-based contrast agents as biodiagnostics. The polycatechol nanoparticles are proposed as suitable for preclinical investigations into their viability as gadolinium-free, safe, and effective imaging agents for MRI contrast enhancement. PMID:26681255

  7. Agent review phase one report.

    SciTech Connect

    Zubelewicz, Alex Tadeusz; Davis, Christopher Edward; Bauer, Travis LaDell

    2009-12-01

    This report summarizes the findings for phase one of the agent review and discusses the review methods and results. The phase one review identified a short list of agent systems that would prove most useful in the service architecture of an information management, analysis, and retrieval system. Reviewers evaluated open-source and commercial multi-agent systems and scored them based upon viability, uniqueness, ease of development, ease of deployment, and ease of integration with other products. Based on these criteria, reviewers identified the ten most appropriate systems. The report also mentions several systems that reviewers deemed noteworthy for the ideas they implement, even if those systems are not the best choices for information management purposes.

  8. Thyroid Dysfunction from Antineoplastic Agents

    PubMed Central

    Larsen, P. Reed; Marqusee, Ellen

    2011-01-01

    Unlike cytotoxic agents that indiscriminately affect rapidly dividing cells, newer antineoplastic agents such as targeted therapies and immunotherapies are associated with thyroid dysfunction. These include tyrosine kinase inhibitors, bexarotene, radioiodine-based cancer therapies, denileukin diftitox, alemtuzumab, interferon-α, interleukin-2, ipilimumab, tremelimumab, thalidomide, and lenalidomide. Primary hypothyroidism is the most common side effect, although thyrotoxicosis and effects on thyroid-stimulating hormone secretion and thyroid hormone metabolism have also been described. Most agents cause thyroid dysfunction in 20%–50% of patients, although some have even higher rates. Despite this, physicians may overlook drug-induced thyroid dysfunction because of the complexity of the clinical picture in the cancer patient. Symptoms of hypothyroidism, such as fatigue, weakness, depression, memory loss, cold intolerance, and cardiovascular effects, may be incorrectly attributed to the primary disease or to the antineoplastic agent. Underdiagnosis of thyroid dysfunction can have important consequences for cancer patient management. At a minimum, the symptoms will adversely affect the patient’s quality of life. Alternatively, such symptoms can lead to dose reductions of potentially life-saving therapies. Hypothyroidism can also alter the kinetics and clearance of medications, which may lead to undesirable side effects. Thyrotoxicosis can be mistaken for sepsis or a nonendocrinologic drug side effect. In some patients, thyroid disease may indicate a higher likelihood of tumor response to the agent. Both hypothyroidism and thyrotoxicosis are easily diagnosed with inexpensive and specific tests. In many patients, particularly those with hypothyroidism, the treatment is straightforward. We therefore recommend routine testing for thyroid abnormalities in patients receiving these antineoplastic agents. PMID:22010182

  9. Thyroid dysfunction from antineoplastic agents.

    PubMed

    Hamnvik, Ole-Petter Riksfjord; Larsen, P Reed; Marqusee, Ellen

    2011-11-01

    Unlike cytotoxic agents that indiscriminately affect rapidly dividing cells, newer antineoplastic agents such as targeted therapies and immunotherapies are associated with thyroid dysfunction. These include tyrosine kinase inhibitors, bexarotene, radioiodine-based cancer therapies, denileukin diftitox, alemtuzumab, interferon-α, interleukin-2, ipilimumab, tremelimumab, thalidomide, and lenalidomide. Primary hypothyroidism is the most common side effect, although thyrotoxicosis and effects on thyroid-stimulating hormone secretion and thyroid hormone metabolism have also been described. Most agents cause thyroid dysfunction in 20%-50% of patients, although some have even higher rates. Despite this, physicians may overlook drug-induced thyroid dysfunction because of the complexity of the clinical picture in the cancer patient. Symptoms of hypothyroidism, such as fatigue, weakness, depression, memory loss, cold intolerance, and cardiovascular effects, may be incorrectly attributed to the primary disease or to the antineoplastic agent. Underdiagnosis of thyroid dysfunction can have important consequences for cancer patient management. At a minimum, the symptoms will adversely affect the patient's quality of life. Alternatively, such symptoms can lead to dose reductions of potentially life-saving therapies. Hypothyroidism can also alter the kinetics and clearance of medications, which may lead to undesirable side effects. Thyrotoxicosis can be mistaken for sepsis or a nonendocrinologic drug side effect. In some patients, thyroid disease may indicate a higher likelihood of tumor response to the agent. Both hypothyroidism and thyrotoxicosis are easily diagnosed with inexpensive and specific tests. In many patients, particularly those with hypothyroidism, the treatment is straightforward. We therefore recommend routine testing for thyroid abnormalities in patients receiving these antineoplastic agents. PMID:22010182

  10. Autonomous sensor manager agents (ASMA)

    NASA Astrophysics Data System (ADS)

    Osadciw, Lisa A.

    2004-04-01

    Autonomous sensor manager agents are presented as an algorithm to perform sensor management within a multisensor fusion network. The design of the hybrid ant system/particle swarm agents is described in detail with some insight into their performance. Although the algorithm is designed for the general sensor management problem, a simulation example involving 2 radar systems is presented. Algorithmic parameters are determined by the size of the region covered by the sensor network, the number of sensors, and the number of parameters to be selected. With straight forward modifications, this algorithm can be adapted for most sensor management problems.

  11. Serologic Testing for Human Granulocytic Ehrlichiosis at a National Referral Center

    PubMed Central

    Comer, James A.; Nicholson, William L.; Olson, James G.; Childs, James E.

    1999-01-01

    An indirect immunofluorescence assay (IFA) was used to identify patients with antibodies reactive to the human granulocytic ehrlichiosis (HGE) agent. Serum samples collected from clinically ill individuals were submitted to the Centers for Disease Control and Prevention by physicians via state health departments from throughout the United States and tested against a panel of ehrlichial and rickettsial pathogens. Antibodies reactive to the HGE agent were detected in 142 (8.9%) of 1,602 individuals tested. There were 19 confirmed and 59 probable (n = 78) cases of HGE as defined by seroconversion or a fourfold or higher titer to the HGE agent than to the Ehrlichia chaffeensis antigens. The average age of patients with HGE was 57 years, and males accounted for 53 (68%) of the patients. Cases of HGE occurred in 21 states; 47 (60%) of the cases occurred in Connecticut (n = 14), New York (n = 18), and Wisconsin (n = 15). Onset of HGE was identified from April through December, with cases peaking in June and July. The earliest confirmed cases of HGE occurred in 1987 in Wisconsin and 1988 in Florida. No fatalities were reported among the 78 patients with confirmed or probable HGE. Reactivity to the HGE agent and to either Coxiella burnetii, Rickettsia rickettsii, or Rickettsia typhi was infrequent; however, 74 (52%) of the 142 individuals who were positive for HGE had at least one serum sample that also reacted to the E. chaffeensis antigen. Thirty-four persons with confirmed or probable human monocytic ehrlichiosis due to E. chaffeensis also had antibodies to the HGE agent in at least one serum sample. The specific etiologic agent for 30 patients was not ascribed because of similarity of titers to both ehrlichial antigens. The use of both antigens may be required to correctly diagnose most cases of human ehrlichiosis, especially in geographic regions where both the HGE agent and E. chaffeensis occur. PMID:9986812

  12. Exposure to toxic environmental agents.

    PubMed

    2013-10-01

    Reducing exposure to toxic environmental agents is a critical area of intervention for obstetricians, gynecologists, and other reproductive health care professionals. Patient exposure to toxic environmental chemicals and other stressors is ubiquitous, and preconception and prenatal exposure to toxic environmental agents can have a profound and lasting effect on reproductive health across the life course.Prenatal exposure to certain chemicals has been documented to increase the risk of cancer in childhood; adult male exposure to pesticides is linked to altered semen quality, sterility, and prostate cancer; and postnatal exposure to some pesticides can interfere with all developmental stages of reproductive function in adult females, including puberty, menstruation and ovulation, fertility and fecundity, and menopause. Many environmental factors harmful to reproductive health disproportionately affect vulnerable and underserved populations,which leaves some populations, including underserved women, more vulnerable to adverse reproductive health effects than other populations. The evidence that links exposure to toxic environmental agents and adverse reproductive and developmental health outcomes is sufficiently robust, and the American College of Obstetricians and Gynecologists and the American Society for Reproductive Medicine join leading scientists and other clinical practitioners in calling for timely action to identify and reduce exposure to toxic environmental agents while addressing the consequences of such exposure.

  13. Exposure to toxic environmental agents.

    PubMed

    2013-10-01

    : Reducing exposure to toxic environmental agents is a critical area of intervention for obstetricians, gynecologists, and other reproductive health care professionals. Patient exposure to toxic environmental chemicals and other stressors is ubiquitous, and preconception and prenatal exposure to toxic environmental agents can have a profound and lasting effect on reproductive health across the life course. Prenatal exposure to certain chemicals has been documented to increase the risk of cancer in childhood; adult male exposure to pesticides is linked to altered semen quality, sterility, and prostate cancer; and postnatal exposure to some pesticides can interfere with all developmental stages of reproductive function in adult females, including puberty, menstruation and ovulation, fertility and fecundity, and menopause. Many environmental factors harmful to reproductive health disproportionately affect vulnerable and underserved populations, which leaves some populations, including underserved women, more vulnerable to adverse reproductive health effects than other populations. The evidence that links exposure to toxic environmental agents and adverse reproductive and developmental health outcomes is sufficiently robust, and the American College of Obstetricians and Gynecologists and the American Society for Reproductive Medicine join leading scientists and other clinical practitioners in calling for timely action to identify and reduce exposure to toxic environmental agents while addressing the consequences of such exposure.

  14. Triggered pore-forming agents

    DOEpatents

    Bayley, H.; Walker, B.J.; Chang, C.Y.; Niblack, B.; Panchal, R.

    1998-07-07

    An inactive pore-forming agent is revealed which is activated to lytic function by a condition such as pH, light, heat, reducing potential, or metal ion concentration, or substance such as a protease, at the surface of a cell. 30 figs.

  15. 7 CFR 4290.1620 - Functions of agents, including Central Registration Agent, Selling Agent and Fiscal Agent.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., DEPARTMENT OF AGRICULTURE RURAL BUSINESS INVESTMENT COMPANY (âRBICâ) PROGRAM Financial Assistance for RBICs (Leverage) Funding Leverage by Use of Guaranteed Trust Certificates (âtcsâ) § 4290.1620 Functions of agents... to: (i) Establish performance criteria for Poolers. (ii) Monitor and evaluate the financial...

  16. Direct Vasodilators and Sympatholytic Agents.

    PubMed

    McComb, Meghan N; Chao, James Y; Ng, Tien M H

    2016-01-01

    Direct vasodilators and sympatholytic agents were some of the first antihypertensive medications discovered and utilized in the past century. However, side effect profiles and the advent of newer antihypertensive drug classes have reduced the use of these agents in recent decades. Outcome data and large randomized trials supporting the efficacy of these medications are limited; however, in general the blood pressure-lowering effect of these agents has repeatedly been shown to be comparable to other more contemporary drug classes. Nevertheless, a landmark hypertension trial found a negative outcome with a doxazosin-based regimen compared to a chlorthalidone-based regimen, leading to the removal of α-1 adrenergic receptor blockers as first-line monotherapy from the hypertension guidelines. In contemporary practice, direct vasodilators and sympatholytic agents, particularly hydralazine and clonidine, are often utilized in refractory hypertension. Hydralazine and minoxidil may also be useful alternatives for patients with renal dysfunction, and both hydralazine and methyldopa are considered first line for the treatment of hypertension in pregnancy. Hydralazine has also found widespread use for the treatment of systolic heart failure in combination with isosorbide dinitrate (ISDN). The data to support use of this combination in African Americans with heart failure are particularly robust. Hydralazine with ISDN may also serve as an alternative for patients with an intolerance to angiotensin antagonists. Given these niche indications, vasodilators and sympatholytics are still useful in clinical practice; therefore, it is prudent to understand the existing data regarding efficacy and the safe use of these medications. PMID:26033778

  17. Nucleotide cleaving agents and method

    DOEpatents

    Que, Jr., Lawrence; Hanson, Richard S.; Schnaith, Leah M. T.

    2000-01-01

    The present invention provides a unique series of nucleotide cleaving agents and a method for cleaving a nucleotide sequence, whether single-stranded or double-stranded DNA or RNA, using and a cationic metal complex having at least one polydentate ligand to cleave the nucleotide sequence phosphate backbone to yield a hydroxyl end and a phosphate end.

  18. 7 CFR 4290.1620 - Functions of agents, including Central Registration Agent, Selling Agent and Fiscal Agent.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 15 2011-01-01 2011-01-01 false Functions of agents, including Central Registration..., DEPARTMENT OF AGRICULTURE RURAL BUSINESS INVESTMENT COMPANY (âRBICâ) PROGRAM Financial Assistance for RBICs (Leverage) Funding Leverage by Use of Guaranteed Trust Certificates (âtcsâ) § 4290.1620 Functions of...

  19. SEM: A Cultural Change Agent

    ERIC Educational Resources Information Center

    Barnes, Bradley; Bourke, Brian

    2015-01-01

    The authors advance the concept that institutional culture is a purposeful framework by which to view SEM's utility, particularly as a cultural change agent. Through the connection of seemingly independent functions of performance and behavior, implications emerge that deepen the understanding of the influence of culture on performance outcomes…

  20. Limonene and tetrahydrofurfuryl alcohol cleaning agent

    DOEpatents

    Bohnert, George W.; Carter, Richard D.; Hand, Thomas E.; Powers, Michael T.

    1996-05-07

    The present invention is a tetrahydrofurfuryl alcohol and limonene or terpineol cleaning agent and method for formulating and/or using the cleaning agent. This cleaning agent effectively removes both polar and nonpolar contaminants from various electrical and mechanical parts and is readily used without surfactants, thereby reducing the need for additional cleaning operations. The cleaning agent is warm water rinsable without the use of surfactants. The cleaning agent can be azeotropic, enhancing ease of use in cleaning operations and ease of recycling.

  1. Limonene and tetrahydrofurfuryl alcohol cleaning agent

    DOEpatents

    Bohnert, G.W.; Carter, R.D.; Hand, T.E.; Powers, M.T.

    1997-10-21

    The present invention is a tetrahydrofurfuryl alcohol and limonene cleaning agent and method for formulating and/or using the cleaning agent. This cleaning agent effectively removes both polar and nonpolar contaminants from various electrical and mechanical parts and is readily used without surfactants, thereby reducing the need for additional cleaning operations. The cleaning agent is warm water rinsable without the use of surfactants. The cleaning agent can be azeotropic, enhancing ease of use in cleaning operations and ease of recycling.

  2. Limonene and tetrahydrofurfurly alcohol cleaning agent

    DOEpatents

    Bohnert, George W.; Carter, Richard D.; Hand, Thomas E.; Powers, Michael T.

    1997-10-21

    The present invention is a tetrahydrofurfuryl alcohol and limonene cleaning agent and method for formulating and/or using the cleaning agent. This cleaning agent effectively removes both polar and nonpolar contaminants from various electrical and mechanical parts and is readily used without surfactants, thereby reducing the need for additional cleaning operations. The cleaning agent is warm water rinsable without the use of surfactants. The cleaning agent can be azeotropic, enhancing ease of use in cleaning operations and ease of recycling.

  3. Halide test agent replacement study

    SciTech Connect

    Banks, E.M.; Freeman, W.P.; Kovach, B.J.

    1995-02-01

    The intended phaseout of the chlorofluorocarbons (CFCs) from commercial use required the evaluation of substitute materials for the testing for leak paths through both individual adsorbers and installed adsorbent banks. The American Society of Mechanical Engineers (ASME) Committee on Nuclear Air and Gas Treatment (CONAGT) is in charge of maintaining the standards and codes specifying adsorbent leak test methods for the nuclear safety related air cleaning systems. The currently published standards and codes cite the use of R-11, R-12 and R-112 for leak path test agents. All of these compounds are CFCs. There are other agencies and organizations (USDOE, USDOD and USNRC) also specifying testing for leak paths or in some cases for special life tests using the above compounds. The CONAGT has recently developed criteria for the suitability evaluation of substitute test agents. On the basis of these criteria, several compounds were evaluated for their acceptability as adsorbent bed leak and life test agents. The ASME CONAGT Test Agent Qualification Criteria. The test agent qualification is based on the following parameters: (1) Similar retention times on activated carbons at the same concentration levels as one of the following: R-11, R-12, R-112 or R-112a. (2) Similar lower detection limit sensitivity and precision in the concentration range of use as R-11, R-12, R-112 and R-112a. (3) Gives the same in-place leak test results as R-11, R-12, R-112, or R-112a. (4) Chemical and radiological stability under the use conditions. (5) Causes no degradation of the carbon and its impregnant or of the other NATS components under the use conditions. (6) Is listed in the USEPA Toxic Substances Control Act (TSCA) inventory for commercial use.

  4. Does an Agent Matter? The Effects of Animated Pedagogical Agents on Multimedia Environments.

    ERIC Educational Resources Information Center

    Craig, Scotty D.; Gholson, Barry

    Data are presented on the effects of Animated Agents on multimedia learning environments with specific concerns of split attention and modality effects. The study was a 3 (agent properties: agent only, agent with gestures, no agent) x 3 (picture features: static picture, sudden onset, animation) factorial design with outcome measures of mental…

  5. The New Agent: A Qualitative Study to Strategically Adapt New Agent Professional Development

    ERIC Educational Resources Information Center

    Baker, Lauri M.; Hadley, Gregg

    2014-01-01

    The qualitative study reported here assessed the needs of agents related to new agent professional development to improve the current model. Agents who participated in new agent professional development within the last 5 years were selected to participate in focus groups to determine concerns and continued needs. Agents enjoyed networking and…

  6. Q Fever Outbreak Among Travelers to Germany Who Received Live Cell Therapy--United States and Canada, 2014.

    PubMed

    Robyn, Misha P; Newman, Alexandra P; Amato, Michael; Walawander, Mary; Kothe, Cynthia; Nerone, James D; Pomerantz, Cynthia; Behravesh, Casey Barton; Biggs, Holly M; Dahlgren, F Scott; Pieracci, Emily G; Whitfield, Yvonne; Sider, Doug; Ozaldin, Omar; Berger, Lisa; Buck, Peter A; Downing, Mark; Blog, Debra

    2015-10-01

    During September–November 2014, the New York State Department of Health (NYSDOH) was notified of five New York state residents who had tested seropositive for Coxiella burnetii, the causative agent of Q fever. All five patients had symptoms compatible with Q fever (e.g., fever, fatigue, chills, and headache) and a history of travel to Germany to receive a medical treatment called "live cell therapy" (sometimes called "fresh cell therapy") in May 2014. Live cell therapy is the practice of injecting processed cells from organs or fetuses of nonhuman animals (e.g., sheep) into human recipients. It is advertised to treat a variety of health conditions. This practice is unavailable in the United States; however, persons can travel to foreign locations to receive injections. Local health departments interviewed the patients, and NYSDOH notified CDC and posted a report on CDC’s Epidemic Information Exchange to solicit additional cases. Clinical and exposure information for each patient was reported to the Robert Koch Institute in Germany, which forwarded the information to local health authorities. A Canada resident who also received live cell therapy in May 2014 was diagnosed with Q fever in July 2014. Clinicians should be aware of health risks, such as Q fever and other zoonotic diseases, among patients with a history of receiving treatment with live cell therapy products. PMID:26421460

  7. Neuroprotective "agents" in surgery. Secret "agent" man, or common "agent" machine?

    NASA Technical Reports Server (NTRS)

    Andrews, R. J.

    1999-01-01

    The search for clinically-effective neuroprotective agents has received enormous support in recent years--an estimated $200 million by pharmaceutical companies on clinical trials for traumatic brain injury alone. At the same time, the pathophysiology of brain injury has proved increasingly complex, rendering the likelihood of a single agent "magic bullet" even more remote. On the other hand, great progress continues with technology that makes surgery less invasive and less risky. One example is the application of endovascular techniques to treat coronary artery stenosis, where both the invasiveness of sternotomy and the significant neurological complication rate (due to microemboli showering the cerebral vasculature) can be eliminated. In this paper we review aspects of intraoperative neuroprotection both present and future. Explanations for the slow progress on pharmacologic neuroprotection during surgery are presented. Examples of technical advances that have had great impact on neuroprotection during surgery are given both from coronary artery stenosis surgery and from surgery for Parkinson's disease. To date, the progress in neuroprotection resulting from such technical advances is an order of magnitude greater than that resulting from pharmacologic agents used during surgery. The progress over the last 20 years in guidance during surgery (CT and MRI image-guidance) and in surgical access (endoscopic and endovascular techniques) will soon be complemented by advances in our ability to evaluate biological tissue intraoperatively in real-time. As an example of such technology, the NASA Smart Probe project is considered. In the long run (i.e., in 10 years or more), pharmacologic "agents" aimed at the complex pathophysiology of nervous system injury in man will be the key to true intraoperative neuroprotection. In the near term, however, it is more likely that mundane "agents" based on computers, microsensors, and microeffectors will be the major impetus to improved

  8. CATS-based Agents That Err

    NASA Technical Reports Server (NTRS)

    Callantine, Todd J.

    2002-01-01

    This report describes preliminary research on intelligent agents that make errors. Such agents are crucial to the development of novel agent-based techniques for assessing system safety. The agents extend an agent architecture derived from the Crew Activity Tracking System that has been used as the basis for air traffic controller agents. The report first reviews several error taxonomies. Next, it presents an overview of the air traffic controller agents, then details several mechanisms for causing the agents to err in realistic ways. The report presents a performance assessment of the error-generating agents, and identifies directions for further research. The research was supported by the System-Wide Accident Prevention element of the FAA/NASA Aviation Safety Program.

  9. Chaotic neurodynamics for autonomous agents.

    PubMed

    Harter, Derek; Kozma, Robert

    2005-05-01

    Mesoscopic level neurodynamics study the collective dynamical behavior of neural populations. Such models are becoming increasingly important in understanding large-scale brain processes. Brains exhibit aperiodic oscillations with a much more rich dynamical behavior than fixed-point and limit-cycle approximation allow. Here we present a discretized model inspired by Freeman's K-set mesoscopic level population model. We show that this version is capable of replicating the important principles of aperiodic/chaotic neurodynamics while being fast enough for use in real-time autonomous agent applications. This simplification of the K model provides many advantages not only in terms of efficiency but in simplicity and its ability to be analyzed in terms of its dynamical properties. We study the discrete version using a multilayer, highly recurrent model of the neural architecture of perceptual brain areas. We use this architecture to develop example action selection mechanisms in an autonomous agent. PMID:15940987

  10. Novel Antiangiogenic Agents in Dermatology

    PubMed Central

    Berrios, Ricardo L.; Arbiser, Jack L.

    2011-01-01

    Because angiogenesis underlies the pathogenesis of numerous conditions (cancer, psoriasis, macular degeneration), there is a pressing need for continued investigations into angiogenic signaling and potential drug targets. Antiangiogenic agents can be classified as either direct or indirect. Direct antiangiogenics act on untransformed endothelial cells to prevent differentiation and proliferation; indirect antiangiogenics act to inhibit factors involved in proangiogenic signaling. Agents currently available with dermatologic indications are few, while several established and novel biologics targeting various proangiogenic factors are currently being investigated for potential dermatologic uses, but the jury is still out on their efficacy and safety. In this review, we highlight our experience with a group of existing and novel, small molecules that combine several modes of action against angiogenesis in addition to other properties – triarylmethane dyes and fulvene derivatives. PMID:21172300

  11. Bacteriocins as Potential Anticancer Agents

    PubMed Central

    Kaur, Sumanpreet; Kaur, Sukhraj

    2015-01-01

    Cancer remains one of the leading causes of deaths worldwide, despite advances in its treatment and detection. The conventional chemotherapeutic agents used for the treatment of cancer have non-specific toxicity toward normal body cells that cause various side effects. Secondly, cancer cells are known to develop chemotherapy resistance in due course of treatment. Thus, the demand for novel anti-cancer agents is increasing day by day. Some of the experimental studies have reported the therapeutic potential of bacteriocins against various types of cancer cell lines. Bacteriocins are ribosomally-synthesized cationic peptides secreted by almost all groups of bacteria. Some bacteriocins have shown selective cytotoxicity toward cancer cells as compared to normal cells. This makes them promising candidates for further investigation and clinical trials. In this review article, we present the overview of the various cancer cell-specific cytotoxic bacteriocins, their mode of action and efficacies. PMID:26617524

  12. Bacteriocins as Potential Anticancer Agents.

    PubMed

    Kaur, Sumanpreet; Kaur, Sukhraj

    2015-01-01

    Cancer remains one of the leading causes of deaths worldwide, despite advances in its treatment and detection. The conventional chemotherapeutic agents used for the treatment of cancer have non-specific toxicity toward normal body cells that cause various side effects. Secondly, cancer cells are known to develop chemotherapy resistance in due course of treatment. Thus, the demand for novel anti-cancer agents is increasing day by day. Some of the experimental studies have reported the therapeutic potential of bacteriocins against various types of cancer cell lines. Bacteriocins are ribosomally-synthesized cationic peptides secreted by almost all groups of bacteria. Some bacteriocins have shown selective cytotoxicity toward cancer cells as compared to normal cells. This makes them promising candidates for further investigation and clinical trials. In this review article, we present the overview of the various cancer cell-specific cytotoxic bacteriocins, their mode of action and efficacies.

  13. [Pharmacology of bone anabolic agents].

    PubMed

    Matsumoto, Toshio

    2015-10-01

    Bone is constantly remodeled to maintain its volume, structural integrity and strength Currently available bone anabolic agent is teriparatide. Teriparatide increases bone mass and strength via both remodeling-dependent and -independent mechanisms, although remodeling-dependent mechanism overweighs the other. Canonical Wnt signal plays an important role in enhancing osteoblast differentiation and bone formation, and its osteocyte-derived inhibitor, sclerostin, regulates bone formation via the regulation of Wnt signaling. Anti-sclerostin antibody stimulates Wnt signaling and enhances bone formation. Phase II clinical trials with anti-sclerostin antibodies, romosozumab and blosozumab, demonstrated a marked increase in bone mineral density after one year of treatment. The new modality of anabolic agents via remodeling-independent stimulation of bone formation may open up a new avenue for the treatment of osteoporosis.

  14. Oral agents in multiple sclerosis.

    PubMed

    Lorefice, L; Fenu, G; Frau, J; Coghe, G C; Marrosu, M G; Cocco, E

    2015-01-01

    Multiple sclerosis (MS) is a complex autoimmune disease of the central nervous system. Disease-modifying drugs licensed for MS treatment have been developed to reduce relapse rates and halt disease progression. The majority of current MS drugs involve regular, parenteral administration, affecting long-term adherence and thus reducing treatment efficacy. Over the last two decades great progress has been made towards developing new MS therapies with different modes of action and biologic effects. In particular, oral drugs have generated much interest because of their convenience and positive impact on medication adherence. Fingolimod was the first launched oral treatment for relapsing-remitting MS; recently, Teriflunomide and Dimethyl fumarate have also been approved as oral disease-modifying agents. In this review, we summarize and discuss the history, pharmacodynamics, efficacy, and safety of oral agents that have been approved or are under development for the selective treatment of MS. PMID:25924620

  15. Hyperlipidemia sink for anesthetic agents.

    PubMed

    Johnson, Thomas J; Porhomayon, Jahan; Nader, Nader D; Eldesouki, Enas; Smith, Kelly; Hobika, Geoffrey G

    2016-11-01

    We present a case that involves anesthetic resistance during anesthesia for electroconvulsive therapy. Despite adequate dosing of both intravenous and inhalation anesthetics, our patient was resistant to induction of the state of general anesthesia. Subsequently, we noticed extreme hyperlipidemia. We hypothesized that the patient's extreme hyperlipidemia served as an anesthetic "sink" and prevented the full dose of intravenous agents from quickly reaching their intended site of action.

  16. Pharmacologic Agents for Chronic Diarrhea.

    PubMed

    Lee, Kwang Jae

    2015-10-01

    Chronic diarrhea is usually associated with a number of non-infectious causes. When definitive treatment is unavailable, symptomatic drug therapy is indicated. Pharmacologic agents for chronic diarrhea include loperamide, 5-hydroxytryptamine type 3 (5-HT3) receptor antagonists, diosmectite, cholestyramine, probiotics, antispasmodics, rifaximin, and anti-inflammatory agents. Loperamide, a synthetic opiate agonist, decreases peristaltic activity and inhibits secretion, resulting in the reduction of fluid and electrolyte loss and an increase in stool consistency. Cholestyramine is a bile acid sequestrant that is generally considered as the first-line treatment for bile acid diarrhea. 5-HT3 receptor antagonists have significant benefits in patients with irritable bowel syndrome (IBS) with diarrhea. Ramosetron improves stool consistency as well as global IBS symptoms. Probiotics may have a role in the prevention of antibiotic-associated diarrhea. However, data on the role of probiotics in the treatment of chronic diarrhea are lacking. Diosmectite, an absorbent, can be used for the treatment of chronic functional diarrhea, radiation-induced diarrhea, and chemotherapy-induced diarrhea. Antispasmodics including alverine citrate, mebeverine, otilonium bromide, and pinaverium bromide are used for relieving diarrheal symptoms and abdominal pain. Rifaximin can be effective for chronic diarrhea associated with IBS and small intestinal bacterial overgrowth. Budesonide is effective in both lymphocytic colitis and collagenous colitis. The efficacy of mesalazine in microscopic colitis is weak or remains uncertain. Considering their mechanisms of action, these agents should be prescribed properly. PMID:26576135

  17. Mortality among agricultural extension agents.

    PubMed

    Alavanja, M C; Blair, A; Merkle, S; Teske, J; Eaton, B

    1988-01-01

    The mortality experience of agricultural extension agents in the Cooperative Extension Service (CES) of the U.S. Department of Agriculture who died during the period January 1, 1970-December 31, 1979 (n = 1,495 white males) was evaluated in proportionate-mortality and case-control studies. The proportionate-mortality analysis was used to identify cancers that might be elevated in this occupational group compared with the U.S. white male population. All cancers with a significantly elevated proportionate-mortality ratio were more thoroughly evaluated in the case-control study, where there is presumably less of a selection bias in the comparison. In the case-control study, leukemia demonstrated a statistically significant linear trend with duration of employment as an extension agent. Smaller, but nonsignificant, trends were seen for non-Hodgkin's lymphoma, multiple myeloma, and brain cancer. The odds ratio for Hodgkin's disease and cancers of the colon, prostate, and kidney did not vary with the number of years on the job. These patterns resemble cancer risks seen among farmers, suggesting that agricultural factors may also play a role in the origin of these tumors among extension agents.

  18. Chelating agents and cadmium intoxication

    SciTech Connect

    Shinobu, L.A.

    1985-01-01

    A wide range of conventional chelating agents have been screened for (a) antidotal activity in acute cadmium poisoning and (b) ability to reduce aged liver and kidney deposits of cadmium. Chelating agents belonging to the dithiocarbamate class have been synthesized and tested in both the acute and chronic modes of cadmium intoxication. Several dithiocarbamates, not only provide antidotal rescue, but also substantially decrease the intracellular deposits of cadmium associated with chronic cadmium intoxication. Fractionating the cytosol from the livers and kidneys of control and treated animals by Sephadex G-25 gel filtration clearly demonstrates that the dithiocarbamates are reducing the level of metallothionein-bound cadmium. However, the results of cell culture (Ehrlich ascites) studies designed to investigate the removal of cadmium from metallothionein and subsequent transport of the resultant cadmium complex across the cell membrane were inconclusive. In other in vitro investigations, the interaction between isolated native Cd, Zn-metallothionein and several chelating agents was explored. Ultracentrifugation, equilibrium dialysis, and Sephadex G-25 gel filtration studies have been carried out in an attempt to determine the rate of removal of cadmium from metallothionein by these small molecules. Chemical shifts for the relevant cadmium-dithiocarbamate complexes have been determined using natural abundance Cd-NMR.

  19. Pharmacologic Agents for Chronic Diarrhea

    PubMed Central

    2015-01-01

    Chronic diarrhea is usually associated with a number of non-infectious causes. When definitive treatment is unavailable, symptomatic drug therapy is indicated. Pharmacologic agents for chronic diarrhea include loperamide, 5-hydroxytryptamine type 3 (5-HT3) receptor antagonists, diosmectite, cholestyramine, probiotics, antispasmodics, rifaximin, and anti-inflammatory agents. Loperamide, a synthetic opiate agonist, decreases peristaltic activity and inhibits secretion, resulting in the reduction of fluid and electrolyte loss and an increase in stool consistency. Cholestyramine is a bile acid sequestrant that is generally considered as the first-line treatment for bile acid diarrhea. 5-HT3 receptor antagonists have significant benefits in patients with irritable bowel syndrome (IBS) with diarrhea. Ramosetron improves stool consistency as well as global IBS symptoms. Probiotics may have a role in the prevention of antibiotic-associated diarrhea. However, data on the role of probiotics in the treatment of chronic diarrhea are lacking. Diosmectite, an absorbent, can be used for the treatment of chronic functional diarrhea, radiation-induced diarrhea, and chemotherapy-induced diarrhea. Antispasmodics including alverine citrate, mebeverine, otilonium bromide, and pinaverium bromide are used for relieving diarrheal symptoms and abdominal pain. Rifaximin can be effective for chronic diarrhea associated with IBS and small intestinal bacterial overgrowth. Budesonide is effective in both lymphocytic colitis and collagenous colitis. The efficacy of mesalazine in microscopic colitis is weak or remains uncertain. Considering their mechanisms of action, these agents should be prescribed properly. PMID:26576135

  20. Pharmacologic Agents for Chronic Diarrhea.

    PubMed

    Lee, Kwang Jae

    2015-10-01

    Chronic diarrhea is usually associated with a number of non-infectious causes. When definitive treatment is unavailable, symptomatic drug therapy is indicated. Pharmacologic agents for chronic diarrhea include loperamide, 5-hydroxytryptamine type 3 (5-HT3) receptor antagonists, diosmectite, cholestyramine, probiotics, antispasmodics, rifaximin, and anti-inflammatory agents. Loperamide, a synthetic opiate agonist, decreases peristaltic activity and inhibits secretion, resulting in the reduction of fluid and electrolyte loss and an increase in stool consistency. Cholestyramine is a bile acid sequestrant that is generally considered as the first-line treatment for bile acid diarrhea. 5-HT3 receptor antagonists have significant benefits in patients with irritable bowel syndrome (IBS) with diarrhea. Ramosetron improves stool consistency as well as global IBS symptoms. Probiotics may have a role in the prevention of antibiotic-associated diarrhea. However, data on the role of probiotics in the treatment of chronic diarrhea are lacking. Diosmectite, an absorbent, can be used for the treatment of chronic functional diarrhea, radiation-induced diarrhea, and chemotherapy-induced diarrhea. Antispasmodics including alverine citrate, mebeverine, otilonium bromide, and pinaverium bromide are used for relieving diarrheal symptoms and abdominal pain. Rifaximin can be effective for chronic diarrhea associated with IBS and small intestinal bacterial overgrowth. Budesonide is effective in both lymphocytic colitis and collagenous colitis. The efficacy of mesalazine in microscopic colitis is weak or remains uncertain. Considering their mechanisms of action, these agents should be prescribed properly.

  1. Multi-agent autonomous system

    NASA Technical Reports Server (NTRS)

    Fink, Wolfgang (Inventor); Dohm, James (Inventor); Tarbell, Mark A. (Inventor)

    2010-01-01

    A multi-agent autonomous system for exploration of hazardous or inaccessible locations. The multi-agent autonomous system includes simple surface-based agents or craft controlled by an airborne tracking and command system. The airborne tracking and command system includes an instrument suite used to image an operational area and any craft deployed within the operational area. The image data is used to identify the craft, targets for exploration, and obstacles in the operational area. The tracking and command system determines paths for the surface-based craft using the identified targets and obstacles and commands the craft using simple movement commands to move through the operational area to the targets while avoiding the obstacles. Each craft includes its own instrument suite to collect information about the operational area that is transmitted back to the tracking and command system. The tracking and command system may be further coupled to a satellite system to provide additional image information about the operational area and provide operational and location commands to the tracking and command system.

  2. Agent planning in AgScala

    NASA Astrophysics Data System (ADS)

    Tošić, Saša; Mitrović, Dejan; Ivanović, Mirjana

    2013-10-01

    Agent-oriented programming languages are designed to simplify the development of software agents, especially those that exhibit complex, intelligent behavior. This paper presents recent improvements of AgScala, an agent-oriented programming language based on Scala. AgScala includes declarative constructs for managing beliefs, actions and goals of intelligent agents. Combined with object-oriented and functional programming paradigms offered by Scala, it aims to be an efficient framework for developing both purely reactive, and more complex, deliberate agents. Instead of the Prolog back-end used initially, the new version of AgScala relies on Agent Planning Package, a more advanced system for automated planning and reasoning.

  3. Natural backbone graft copolymers as suspending agents, dispersing agents, filtrate control agents, and viscosifiers

    SciTech Connect

    Meister, J.J.

    1988-05-01

    Free radical, graft copolymerization of water-soluble monomers onto Kraft, pine lignin produces a natural backgone, graft polymer which functions as a thickening or dispersing agent in water-base, bentonite drilling muds. The complex polymers formed by reacting lignin, calcium chloride, a hydroperoxide, and ethene monomers in anerobic solvent have the structures given in this paper. Synthesis methods, possible synthesis mechanism insights, characterization, properties, and drilling mud tests for these samples are presented in this paper.

  4. Chemopreventive Agent Development | Division of Cancer Prevention

    Cancer.gov

    This group promotes and supports research on early chemopreventive agent development, from preclinical studies to pha | Research on early chemopreventive agent development, from preclinical studies to phase I clinical trials.

  5. Intelligent Agents as Cognitive Tools for Education.

    ERIC Educational Resources Information Center

    Baylor, Amy

    1999-01-01

    Examines the educational potential for intelligent agents as cognitive tools. Discusses the role of intelligent agents: managing large amounts of information (information overload), serving as a pedagogical expert, and creating programming environments for the learner. (AEF)

  6. 7 CFR 58.720 - Acidifying agents.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Specifications for Dairy Plants Approved for USDA Inspection and Grading Service 1 Quality Specifications for Raw Material § 58.720 Acidifying agents. Acidifying agents if used shall be those permitted by the Food...

  7. 7 CFR 58.628 - Sweetening agents.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Specifications for Dairy Plants Approved for USDA Inspection and Grading Service 1 Quality Specifications for Raw Material § 58.628 Sweetening agents. Sweetening agents shall be clean and wholesome and consist of one...

  8. Learning other agents` preferences in multiagent negotiation

    SciTech Connect

    Bui, H.H.; Kieronska, D.; Venkatesh, S.

    1996-12-31

    In multiagent systems, an agent does not usually have complete information about the preferences and decision making processes of other agents. This might prevent the agents from making coordinated choices, purely due to their ignorance of what others want. This paper describes the integration of a learning module into a communication-intensive negotiating agent architecture. The learning module gives the agents the ability to learn about other agents` preferences via past interactions. Over time, the agents can incrementally update their models of other agents` preferences and use them to make better coordinated decisions. Combining both communication and learning, as two complement knowledge acquisition methods, helps to reduce the amount of communication needed on average, and is justified in situations where communication is computationally costly or simply not desirable (e.g. to preserve the individual privacy).

  9. Intelligent Agent Architectures: Reactive Planning Testbed

    NASA Technical Reports Server (NTRS)

    Rosenschein, Stanley J.; Kahn, Philip

    1993-01-01

    An Integrated Agent Architecture (IAA) is a framework or paradigm for constructing intelligent agents. Intelligent agents are collections of sensors, computers, and effectors that interact with their environments in real time in goal-directed ways. Because of the complexity involved in designing intelligent agents, it has been found useful to approach the construction of agents with some organizing principle, theory, or paradigm that gives shape to the agent's components and structures their relationships. Given the wide variety of approaches being taken in the field, the question naturally arises: Is there a way to compare and evaluate these approaches? The purpose of the present work is to develop common benchmark tasks and evaluation metrics to which intelligent agents, including complex robotic agents, constructed using various architectural approaches can be subjected.

  10. Extinguishing agent for combustible metal fires

    DOEpatents

    Riley, John F.; Stauffer, Edgar Eugene

    1976-10-12

    A low chloride extinguishing agent for combustible metal fires comprising from substantially 75 to substantially 94 weight percent of sodium carbonate as the basic fire extinguishing material, from substantially 1 to substantially 5 weight percent of a water-repellent agent such as a metal stearate, from substantially 2 to substantially 10 weight percent of a flow promoting agent such as attapulgus clay, and from substantially 3 to substantially 15 weight percent of a polyamide resin as a crusting agent.

  11. Pathogenic agents in freshwater resources

    NASA Astrophysics Data System (ADS)

    Geldreich, Edwin E.

    1996-02-01

    Numerous pathogenic agents have been found in freshwaters used as sources for water supplies, recreational bathing and irrigation. These agents include bacterial pathogens, enteric viruses, several protozoans and parasitic worms more common to tropical waters. Although infected humans are a major source of pathogens, farm animals (cattle, sheep, pigs), animal pets (dogs, cats) and wildlife serve as significant reservoirs and should not be ignored. The range of infected individuals within a given warm-blooded animal group (humans included) may range from 1 to 25%. Survival times for pathogens in the water environment may range from a few days to as much as a year (Ascaris, Taenia eggs), with infective dose levels varying from one viable cell for several primary pathogenic agents to many thousands of cells for a given opportunistic pathogen.As pathogen detection in water is complex and not readily incorporated into routine monitoring, a surrogate is necessary. In general, indicators of faecal contamination provide a positive correlation with intestinal pathogen occurrences only when appropriate sample volumes are examined by sensitive methodology.Pathways by which pathogens reach susceptible water users include ingestion of contaminated water, body contact with polluted recreational waters and consumption of salad crops irrigated by polluted freshwaters. Major contributors to the spread of various water-borne pathogens are sewage, polluted surface waters and stormwater runoff. All of these contributions are intensified during periods of major floods. Several water-borne case histories are cited as examples of breakdowns in public health protection related to water supply, recreational waters and the consumption of contaminated salad crops. In the long term, water resource management must focus on pollution prevention from point sources of waste discharges and the spread of pathogens in watershed stormwater runoff.

  12. Honey - A Novel Antidiabetic Agent

    PubMed Central

    Erejuwa, Omotayo O.; Sulaiman, Siti A.; Wahab, Mohd S. Ab

    2012-01-01

    Diabetes mellitus remains a burden worldwide in spite of the availability of numerous antidiabetic drugs. Honey is a natural substance produced by bees from nectar. Several evidence-based health benefits have been ascribed to honey in the recent years. In this review article, we highlight findings which demonstrate the beneficial or potential effects of honey in the gastrointestinal tract (GIT), on the gut microbiota, in the liver, in the pancreas and how these effects could improve glycemic control and metabolic derangements. In healthy subjects or patients with impaired glucose tolerance or diabetes mellitus, various studies revealed that honey reduced blood glucose or was more tolerable than most common sugars or sweeteners. Pre-clinical studies provided more convincing evidence in support of honey as a potential antidiabetic agent than clinical studies did. The not-too-impressive clinical data could mainly be attributed to poor study designs or due to the fact that the clinical studies were preliminary. Based on the key constituents of honey, the possible mechanisms of action of antidiabetic effect of honey are proposed. The paper also highlights the potential impacts and future perspectives on the use of honey as an antidiabetic agent. It makes recommendations for further clinical studies on the potential antidiabetic effect of honey. This review provides insight on the potential use of honey, especially as a complementary agent, in the management of diabetes mellitus. Hence, it is very important to have well-designed, randomized controlled clinical trials that investigate the reproducibility (or otherwise) of these experimental data in diabetic human subjects. PMID:22811614

  13. 13 CFR 120.951 - Selling agent.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Selling agent. 120.951 Section 120.951 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Development Company Loan Program (504) Debenture Sales and Service Agents § 120.951 Selling agent. The CDC, with...

  14. 13 CFR 120.951 - Selling agent.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 13 Business Credit and Assistance 1 2012-01-01 2012-01-01 false Selling agent. 120.951 Section 120.951 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Development Company Loan Program (504) Debenture Sales and Service Agents § 120.951 Selling agent. The CDC, with...

  15. 13 CFR 120.951 - Selling agent.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 13 Business Credit and Assistance 1 2011-01-01 2011-01-01 false Selling agent. 120.951 Section 120.951 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Development Company Loan Program (504) Debenture Sales and Service Agents § 120.951 Selling agent. The CDC, with...

  16. 13 CFR 120.951 - Selling agent.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 13 Business Credit and Assistance 1 2013-01-01 2013-01-01 false Selling agent. 120.951 Section 120.951 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Development Company Loan Program (504) Debenture Sales and Service Agents § 120.951 Selling agent. The CDC, with...

  17. 13 CFR 120.951 - Selling agent.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 13 Business Credit and Assistance 1 2014-01-01 2014-01-01 false Selling agent. 120.951 Section 120.951 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Development Company Loan Program (504) Debenture Sales and Service Agents § 120.951 Selling agent. The CDC, with...

  18. Hydroxypyridonate chelating agents and synthesis thereof

    DOEpatents

    Raymond, K.N.; Scarrow, R.C.; White, D.L.

    1985-11-12

    Chelating agents having 1-hydroxy-2-pyridinone (HOPO) and related moieties incorporated within their structures, including polydentate HOPO-substituted polyamines such as spermidine and spermine, and HOPO-substituted desferrioxamine. The chelating agents are useful in selectively removing certain cations from solution, and are particularly useful as ferric ion and actinide chelators. Novel syntheses of the chelating agents are provided. 4 tabs.

  19. 24 CFR 232.1011 - Management agents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 2 2014-04-01 2014-04-01 false Management agents. 232.1011 Section... Management agents. (a) An operator or borrower may, with the prior written approval of HUD, execute a management agent agreement setting forth the duties and procedures for matters related to the management...

  20. 24 CFR 232.1011 - Management agents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 2 2013-04-01 2013-04-01 false Management agents. 232.1011 Section... Management agents. (a) An operator or borrower may, with the prior written approval of HUD, execute a management agent agreement setting forth the duties and procedures for matters related to the management...

  1. Construction and Evaluation of Animated Teachable Agents

    ERIC Educational Resources Information Center

    Bodenheimer, Bobby; Williams, Betsy; Kramer, Mattie Ruth; Viswanath, Karun; Balachandran, Ramya; Belynne, Kadira; Biswas, Gautam

    2009-01-01

    This article describes the design decisions, technical approach, and evaluation of the animation and interface components for an agent-based system that allows learners to learn by teaching. Students learn by teaching an animated agent using a visual representation. The agent can answer questions about what she has been taught and take quizzes.…

  2. Online Deception Detection Using BDI Agents

    ERIC Educational Resources Information Center

    Merritts, Richard A.

    2013-01-01

    This research has two facets within separate research areas. The research area of Belief, Desire and Intention (BDI) agent capability development was extended. Deception detection research has been advanced with the development of automation using BDI agents. BDI agents performed tasks automatically and autonomously. This study used these…

  3. Using Intelligent Agents To Assist Educators.

    ERIC Educational Resources Information Center

    Knode, Steve; Knode, Jon-David W.

    This paper begins with background on intelligent agents (software programs built to perform certain specific tasks for the user). A taxonomy that categorizes intelligent agents by the degree of intelligence embedded in the software is presented. Applications of today's intelligent agents are discussed, including specific examples of the following:…

  4. Infants Attribute to Agents Goals and Dispositions

    ERIC Educational Resources Information Center

    Luo, Yuyan; Choi, You-jung

    2012-01-01

    This commentary article is to be published alongside: Hernik, M., & Southgate, V. (2012). What do infants know about agents' goals? The authors see this issue consisting of two closely related questions. First, what is an agent to infants? Second, how do infants attribute goals to agents? Hernik and Southgage (H&S) focused on the second question.…

  5. 7 CFR 1430.210 - MILC agents.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... MILC agents. (a) MILC benefits may be disbursed by a dairy marketing cooperative that serves special... operation may authorize an agent of a dairy cooperative or milk handler affiliated with such cooperative to... 7 Agriculture 10 2010-01-01 2010-01-01 false MILC agents. 1430.210 Section 1430.210...

  6. 46 CFR Sec. 2 - General Agent's requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 8 2014-10-01 2014-10-01 false General Agent's requirements. Sec. 2 Section 2 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY SLOP CHESTS Sec. 2 General Agent's requirements. The General Agent shall: (a) Obtain from the Master, a requisition for...

  7. 46 CFR Sec. 2 - General Agents' authority.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 8 2014-10-01 2014-10-01 false General Agents' authority. Sec. 2 Section 2 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY AUTHORITY AND... AGREEMENT Sec. 2 General Agents' authority. The General Agents are: (a) Hereby delegated authority...

  8. 46 CFR Sec. 2 - General Agents' authority.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 8 2012-10-01 2012-10-01 false General Agents' authority. Sec. 2 Section 2 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY AUTHORITY AND RESPONSIBILITY OF GENERAL AGENTS TO UNDERTAKE EMERGENCY REPAIRS IN FOREIGN PORTS Sec. 2 General Agents'...

  9. 46 CFR Sec. 2 - General Agents' authority.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false General Agents' authority. Sec. 2 Section 2 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY AUTHORITY AND... AGREEMENT Sec. 2 General Agents' authority. The General Agents are: (a) Hereby delegated authority...

  10. 46 CFR Sec. 2 - General Agents' authority.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false General Agents' authority. Sec. 2 Section 2 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY AUTHORITY AND RESPONSIBILITY OF GENERAL AGENTS TO UNDERTAKE EMERGENCY REPAIRS IN FOREIGN PORTS Sec. 2 General Agents'...

  11. 46 CFR Sec. 2 - General Agent's requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 8 2012-10-01 2012-10-01 false General Agent's requirements. Sec. 2 Section 2 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY SLOP CHESTS Sec. 2 General Agent's requirements. The General Agent shall: (a) Obtain from the Master, a requisition for...

  12. 46 CFR Sec. 2 - General Agents' authority.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 8 2013-10-01 2013-10-01 false General Agents' authority. Sec. 2 Section 2 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY AUTHORITY AND... AGREEMENT Sec. 2 General Agents' authority. The General Agents are: (a) Hereby delegated authority...

  13. 46 CFR Sec. 2 - General Agents' authority.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 8 2014-10-01 2014-10-01 false General Agents' authority. Sec. 2 Section 2 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY AUTHORITY AND RESPONSIBILITY OF GENERAL AGENTS TO UNDERTAKE EMERGENCY REPAIRS IN FOREIGN PORTS Sec. 2 General Agents'...

  14. 46 CFR Sec. 2 - General Agent's requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 8 2013-10-01 2013-10-01 false General Agent's requirements. Sec. 2 Section 2 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY SLOP CHESTS Sec. 2 General Agent's requirements. The General Agent shall: (a) Obtain from the Master, a requisition for...

  15. 46 CFR Sec. 2 - General Agents' authority.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 8 2013-10-01 2013-10-01 false General Agents' authority. Sec. 2 Section 2 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY AUTHORITY AND RESPONSIBILITY OF GENERAL AGENTS TO UNDERTAKE EMERGENCY REPAIRS IN FOREIGN PORTS Sec. 2 General Agents'...

  16. 46 CFR Sec. 2 - General Agent's requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false General Agent's requirements. Sec. 2 Section 2 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY SLOP CHESTS Sec. 2 General Agent's requirements. The General Agent shall: (a) Obtain from the Master, a requisition for...

  17. 46 CFR Sec. 2 - General Agents' authority.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 8 2011-10-01 2011-10-01 false General Agents' authority. Sec. 2 Section 2 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY AUTHORITY AND RESPONSIBILITY OF GENERAL AGENTS TO UNDERTAKE EMERGENCY REPAIRS IN FOREIGN PORTS Sec. 2 General Agents'...

  18. 46 CFR Sec. 2 - General Agents' authority.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 8 2012-10-01 2012-10-01 false General Agents' authority. Sec. 2 Section 2 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY AUTHORITY AND... AGREEMENT Sec. 2 General Agents' authority. The General Agents are: (a) Hereby delegated authority...

  19. Agent-based modeling of complex infrastructures

    SciTech Connect

    North, M. J.

    2001-06-01

    Complex Adaptive Systems (CAS) can be applied to investigate complex infrastructures and infrastructure interdependencies. The CAS model agents within the Spot Market Agent Research Tool (SMART) and Flexible Agent Simulation Toolkit (FAST) allow investigation of the electric power infrastructure, the natural gas infrastructure and their interdependencies.

  20. 46 CFR Sec. 2 - General Agent's requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 8 2011-10-01 2011-10-01 false General Agent's requirements. Sec. 2 Section 2 Shipping... General Agent's requirements. The General Agent shall: (a) Obtain from the Master, a requisition for slop..., together with a copy of the vendor's invoice showing items, units, unit cost and totals. (c) Furnish...