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Sample records for ehrlichia chaffeensis tandem

  1. Hacker within! Ehrlichia chaffeensis Effector Driven Phagocyte Reprogramming Strategy

    PubMed Central

    Lina, Taslima T.; Farris, Tierra; Luo, Tian; Mitra, Shubhajit; Zhu, Bing; McBride, Jere W.

    2016-01-01

    Ehrlichia chaffeensis is a small, gram negative, obligately intracellular bacterium that preferentially infects mononuclear phagocytes. It is the etiologic agent of human monocytotropic ehrlichiosis (HME), an emerging life-threatening tick-borne zoonosis. Mechanisms by which E. chaffeensis establishes intracellular infection, and avoids host defenses are not well understood, but involve functionally relevant host-pathogen interactions associated with tandem and ankyrin repeat effector proteins. In this review, we discuss the recent advances in our understanding of the molecular and cellular mechanisms that underlie Ehrlichia host cellular reprogramming strategies that enable intracellular survival. PMID:27303657

  2. Hacker within! Ehrlichia chaffeensis Effector Driven Phagocyte Reprogramming Strategy.

    PubMed

    Lina, Taslima T; Farris, Tierra; Luo, Tian; Mitra, Shubhajit; Zhu, Bing; McBride, Jere W

    2016-01-01

    Ehrlichia chaffeensis is a small, gram negative, obligately intracellular bacterium that preferentially infects mononuclear phagocytes. It is the etiologic agent of human monocytotropic ehrlichiosis (HME), an emerging life-threatening tick-borne zoonosis. Mechanisms by which E. chaffeensis establishes intracellular infection, and avoids host defenses are not well understood, but involve functionally relevant host-pathogen interactions associated with tandem and ankyrin repeat effector proteins. In this review, we discuss the recent advances in our understanding of the molecular and cellular mechanisms that underlie Ehrlichia host cellular reprogramming strategies that enable intracellular survival. PMID:27303657

  3. New Insights into Molecular Ehrlichia chaffeensis-Host Interactions

    PubMed Central

    Wakeel, Abdul; Zhu, Bing; Yu, Xue-jie; McBride, Jere W.

    2010-01-01

    Ehrlichia chaffeensis is an obligately intracellular bacterium that exhibits tropism for mononuclear phagocytes and survives by reprogramming the host cell. Here we review new information regarding the newly characterized effector molecules and the complex network of molecular host-pathogen interactions that the organism exploits enabling it to thrive and persist intracellularly. PMID:20116446

  4. Ehrlichia chaffeensis TRP32 Interacts with Host Cell Targets That Influence Intracellular Survival

    PubMed Central

    Luo, Tian

    2012-01-01

    Ehrlichia chaffeensis is an obligately intracellular bacterium that exhibits tropism for mononuclear phagocytes and survives by evading host cell defense mechanisms. Recently, molecular interactions of E. chaffeensis tandem repeat proteins 47 and 120 (TRP47 and -120) and the eukaryotic host cell have been described. In this investigation, yeast two-hybrid analysis demonstrated that an E. chaffeensis type 1 secretion system substrate, TRP32, interacts with a diverse group of human proteins associated with major biological processes of the host cell, including protein synthesis, trafficking, degradation, immune signaling, cell signaling, iron metabolism, and apoptosis. Eight target proteins, including translation elongation factor 1 alpha 1 (EF1A1), deleted in azoospermia (DAZ)-associated protein 2 (DAZAP2), ferritin light polypeptide (FTL), CD63, CD14, proteasome subunit beta type 1 (PSMB1), ring finger and CCCH-type domain 1 (RC3H1), and tumor protein p53-inducible protein 11 (TP53I11) interacted with TRP32 as determined by coimmunoprecipitation assays, colocalization with TRP32 in HeLa and THP-1 cells, and/or RNA interference. Interactions between TRP32 and host targets localized to the E. chaffeensis morulae or in the host cell cytoplasm adjacent to morulae. Common or closely related interacting partners of E. chaffeensis TRP32, TRP47, and TRP120 demonstrate a molecular convergence on common cellular processes and molecular cross talk between Ehrlichia TRPs and host targets. These findings further support the role of TRPs as effectors that promote intracellular survival. PMID:22547548

  5. Ehrlichia chaffeensis Transcriptome in Mammalian and Arthropod Hosts Reveals Differential Gene Expression and Post Transcriptional Regulation

    PubMed Central

    Kuriakose, Jeeba A.; Miyashiro, Simone; Luo, Tian; Zhu, Bing; McBride, Jere W.

    2011-01-01

    Background Human monocytotropic ehrlichiosis is an emerging life-threatening zoonosis caused by obligately intracellular bacterium, Ehrlichia chaffeensis. E. chaffeensis is transmitted by the lone star tick, Amblyomma americanum, and replicates in mononuclear phagocytes in mammalian hosts. Differences in the E. chaffeensis transcriptome in mammalian and arthropod hosts are unknown. Thus, we determined host-specific E. chaffeensis gene expression in human monocyte (THP-1) and in Amblyomma and Ixodes tick cell lines (AAE2 and ISE6) using a whole genome microarray. Methodology/Principal Findings The majority (∼80%) of E. chaffeensis genes were expressed during infection in human and tick cells. There were few differences observed in E. chaffeensis gene expression between the vector Amblyomma and non-vector Ixodes tick cells, but extensive host-specific and differential gene expression profiles were detected between human and tick cells, including higher transcriptional activity in tick cells and identification of gene subsets that were differentially expressed in the two hosts. Differentially and host-specifically expressed ehrlichial genes encoded major immunoreactive tandem repeat proteins (TRP), the outer membrane protein (OMP-1) family, and hypothetical proteins that were 30–80 amino acids in length. Consistent with previous observations, high expression of p28 and OMP-1B genes was detected in human and tick cells, respectively. Notably, E. chaffeensis genes encoding TRP32 and TRP47 were highly upregulated in the human monocytes and expressed as proteins; however, although TRP transcripts were expressed in tick cells, the proteins were not detected in whole cell lysates demonstrating that TRP expression was post transcriptionally regulated. Conclusions/Significance Ehrlichia gene expression is highly active in tick cells, and differential gene expression among a wide variety of host-pathogen associated genes occurs. Furthermore, we demonstrate that genes

  6. Ehrlichia chaffeensis replication sites in adult Drosophila melanogaster

    PubMed Central

    Drolia, Rishi; Von Ohlen, Tonia; Chapes, Stephen K.

    2012-01-01

    Ehrlichia chaffeensis is a Gram-negative, obligate intracellular bacterium which causes the tick-borne disease human monocytic ehrlichiosis. In vertebrates, E. chaffeensis replicates in monocytes and macrophages. However, no clear cell or tissue tropism has been defined in arthropods. Our group identified two host genes that control E. chaffeensis replication and infection in vivo in Drosophila, Uridine cytidine kinase and separation anxiety. Using the UAS-GAL4 RNAi system, we generated F1 flies (UAS-gene of interest RNAi x tissue-GAL4 flies) that have Uck2 or san silenced in ubiquitous or tissue-specific fashion. When Uck2 or san were suppressed in the hemocytes or in the fat body, E. chaffeensis replicated poorly and caused significantly less severe infections. Silencing of these genes in the eyes, wings, or the salivary glands did not impact fly susceptibility or bacterial replication. Our data suggest that in Drosophila, E. chaffeensis replicates within the hemocytes, the insect homolog of mammalian macrophages, and in the fat body, the liver homolog of mammals. PMID:23306065

  7. Ehrlichia chaffeensis Exploits Host SUMOylation Pathways To Mediate Effector-Host Interactions and Promote Intracellular Survival

    PubMed Central

    Dunphy, Paige Selvy; Luo, Tian

    2014-01-01

    Ehrlichia chaffeensis is an obligately intracellular Gram-negative bacterium that selectively infects mononuclear phagocytes. We recently reported that E. chaffeensis utilizes a type 1 secretion (T1S) system to export tandem repeat protein (TRP) effectors and demonstrated that these effectors interact with a functionally diverse array of host proteins. By way of these interactions, TRP effectors modulate host cell functions; however, the molecular basis of these interactions and their roles in ehrlichial pathobiology are not well defined. In this study, we describe the first bacterial protein posttranslational modification (PTM) by the small ubiquitin-like modifier (SUMO). The E. chaffeensis T1S effector TRP120 is conjugated to SUMO at a carboxy-terminal canonical consensus SUMO conjugation motif in vitro and in human cells. In human cells, TRP120 was selectively conjugated with SUMO2/3 isoforms. Disruption of TRP120 SUMOylation perturbed interactions with known host proteins, through predicted SUMO interaction motif-dependent and -independent mechanisms. E. chaffeensis infection did not result in dramatic changes in the global host SUMOylated protein profile, but a robust colocalization of predominately SUMO1 with ehrlichial inclusions was observed. Inhibiting the SUMO pathway with a small-molecule inhibitor had a significant impact on E. chaffeensis replication and recruitment of the TRP120-interacting protein polycomb group ring finger protein 5 (PCGF5) to the inclusion, indicating that the SUMO pathway is critical for intracellular survival. This study reveals the novel exploitation of the SUMO pathway by Ehrlichia, which facilitates effector-eukaryote interactions necessary to usurp the host and create a permissive intracellular niche. PMID:25047847

  8. Human Granulocytic Ehrlichiosis Agent and Ehrlichia chaffeensis Reside in Different Cytoplasmic Compartments in HL-60 Cells

    PubMed Central

    Mott, Jason; Barnewall, Roy E.; Rikihisa, Yasuko

    1999-01-01

    The human granulocytic ehrlichiosis (HGE) agent resides and multiplies exclusively in cytoplasmic vacuoles of granulocytes. Double immunofluorescence labeling was used to characterize the nature of the HGE agent replicative inclusions and to compare them with inclusions containing the human monocytic ehrlichia, Ehrlichia chaffeensis, in HL-60 cells. Although both Ehrlichia spp. can coinfect HL-60 cells, they resided in separate inclusions. Inclusions of both Ehrlichia spp. were not labeled with either anti-lysosome-associated membrane protein 1 or anti-CD63. Accumulation of myeloperoxidase-positive granules were seen around HGE agent inclusions but not around E. chaffeensis inclusions. 3-(2,4-Dinitroanilino)-3′-amino-N-methyldipropylamine and acridine orange were not localized to either inclusion type. Vacuolar-type H+-ATPase was not colocalized with HGE agent inclusions but was weakly colocalized with E. chaffeensis inclusions. E. chaffeensis inclusions were labeled with the transferrin receptor, early endosomal antigen 1, and rab5, but HGE agent inclusions were not. Some HGE agent and E. chaffeensis inclusions colocalized with major histocompatibility complex class I and II antigens. These two inclusions were not labeled for annexins I, II, IV, and VI; α-adaptin; clathrin heavy chain; or β-coatomer protein. Vesicle-associated membrane protein 2 colocalized to both inclusions. The cation-independent mannose 6-phosphate receptor was not colocalized with either inclusion type. Endogenously synthesized sphingomyelin, from C6-NBD-ceramide, was not incorporated into either inclusion type. Brefeldin A did not affect the growth of either Ehrlichia sp. in HL-60 cells. These results suggest that the HGE agent resides in inclusions which are neither early nor late endosomes and does not fuse with lysosomes or Golgi-derived vesicles, while E. chaffeensis resides in an early endosomal compartment which accumulates the transferrin receptor. PMID:10024584

  9. Ehrlichia chaffeensis TRP120 Activates Canonical Notch Signaling To Downregulate TLR2/4 Expression and Promote Intracellular Survival

    PubMed Central

    Lina, Taslima T.; Dunphy, Paige S.; Luo, Tian

    2016-01-01

    ABSTRACT Ehrlichia chaffeensis preferentially targets mononuclear phagocytes and survives through a strategy of subverting innate immune defenses, but the mechanisms are unknown. We have shown E. chaffeensis type 1 secreted tandem repeat protein (TRP) effectors are involved in diverse molecular pathogen-host interactions, such as the TRP120 interaction with the Notch receptor-cleaving metalloprotease ADAM17. In the present study, we demonstrate E. chaffeensis, via the TRP120 effector, activates the canonical Notch signaling pathway to promote intracellular survival. We found that nuclear translocation of the transcriptionally active Notch intracellular domain (NICD) occurs in response to E. chaffeensis or recombinant TRP120, resulting in upregulation of Notch signaling pathway components and target genes notch1, adam17, hes, and hey. Significant differences in canonical Notch signaling gene expression levels (>40%) were observed during early and late stages of infection, indicating activation of the Notch pathway. We linked Notch pathway activation specifically to the TRP120 effector, which directly interacts with the Notch metalloprotease ADAM17. Using pharmacological inhibitors and small interfering RNAs (siRNAs) against γ-secretase enzyme, Notch transcription factor complex, Notch1, and ADAM17, we demonstrated that Notch signaling is required for ehrlichial survival. We studied the downstream effects and found that E. chaffeensis TRP120-mediated activation of the Notch pathway causes inhibition of the extracellular signal-regulated kinase 1/2 (ERK1/2) and p38 mitogen-activated protein kinase (MAPK) pathways required for PU.1 and subsequent Toll-like receptor 2/4 (TLR2/4) expression. This investigation reveals a novel mechanism whereby E. chaffeensis exploits the Notch pathway to evade the host innate immune response for intracellular survival. PMID:27381289

  10. Naturally occurring Ehrlichia chaffeensis infection in two prosimian primate species: ring-tailed lemurs (Lemur catta) and ruffed lemurs (Varecia variegata).

    PubMed

    Williams, Cathy V; Van Steenhouse, Jan L; Bradley, Julie M; Hancock, Susan I; Hegarty, Barbara C; Breitschwerdt, Edward B

    2002-12-01

    A naturally occurring infection of Ehrlichia chaffeensis in lemurs is described. DNA of Ehrlichia chaffeensis was identified by polymerase chain reaction in peripheral blood from six of eight clinically ill lemurs. Organisms were cultured from the blood of one lemur exhibiting clinical and hematologic abnormalities similar to those of humans infected with E. chaffeensis. PMID:12498671

  11. Ehrlichia chaffeensis Exploits Canonical and Noncanonical Host Wnt Signaling Pathways To Stimulate Phagocytosis and Promote Intracellular Survival

    PubMed Central

    Luo, Tian; Dunphy, Paige S.; Lina, Taslima T.

    2015-01-01

    Ehrlichia chaffeensis invades and survives in phagocytes by modulating host cell processes and evading innate defenses, but the mechanisms are not fully defined. Recently we have determined that E. chaffeensis tandem repeat proteins (TRPs) are type 1 secreted effectors involved in functionally diverse interactions with host targets, including components of the evolutionarily conserved Wnt signaling pathways. In this study, we demonstrated that induction of host canonical and noncanonical Wnt pathways by E. chaffeensis TRP effectors stimulates phagocytosis and promotes intracellular survival. After E. chaffeensis infection, canonical and noncanonical Wnt signalings were significantly stimulated during early stages of infection (1 to 3 h) which coincided with dephosphorylation and nuclear translocation of β-catenin, a major canonical Wnt signal transducer, and NFATC1, a noncanonical Wnt transcription factor. In total, the expression of ∼44% of Wnt signaling target genes was altered during infection. Knockdown of TRP120-interacting Wnt pathway components/regulators and other critical components, such as Wnt5a ligand, Frizzled 5 receptor, β-catenin, nuclear factor of activated T cells (NFAT), and major signaling molecules, resulted in significant reductions in the ehrlichial load. Moreover, small-molecule inhibitors specific for components of canonical and noncanonical (Ca2+ and planar cell polarity [PCP]) Wnt pathways, including IWP-2, which blocks Wnt secretion, significantly decreased ehrlichial infection. TRPs directly activated Wnt signaling, as TRP-coated microspheres triggered phagocytosis which was blocked by Wnt pathway inhibitors, demonstrating a key role of TRP activation of Wnt pathways to induce ehrlichial phagocytosis. These novel findings reveal that E. chaffeensis exploits canonical and noncanonical Wnt pathways through TRP effectors to facilitate host cell entry and promote intracellular survival. PMID:26712203

  12. Ehrlichia chaffeensis Exploits Canonical and Noncanonical Host Wnt Signaling Pathways To Stimulate Phagocytosis and Promote Intracellular Survival.

    PubMed

    Luo, Tian; Dunphy, Paige S; Lina, Taslima T; McBride, Jere W

    2016-03-01

    Ehrlichia chaffeensis invades and survives in phagocytes by modulating host cell processes and evading innate defenses, but the mechanisms are not fully defined. Recently we have determined that E. chaffeensis tandem repeat proteins (TRPs) are type 1 secreted effectors involved in functionally diverse interactions with host targets, including components of the evolutionarily conserved Wnt signaling pathways. In this study, we demonstrated that induction of host canonical and noncanonical Wnt pathways by E. chaffeensis TRP effectors stimulates phagocytosis and promotes intracellular survival. After E. chaffeensis infection, canonical and noncanonical Wnt signalings were significantly stimulated during early stages of infection (1 to 3 h) which coincided with dephosphorylation and nuclear translocation of β-catenin, a major canonical Wnt signal transducer, and NFATC1, a noncanonical Wnt transcription factor. In total, the expression of ∼44% of Wnt signaling target genes was altered during infection. Knockdown of TRP120-interacting Wnt pathway components/regulators and other critical components, such as Wnt5a ligand, Frizzled 5 receptor, β-catenin, nuclear factor of activated T cells (NFAT), and major signaling molecules, resulted in significant reductions in the ehrlichial load. Moreover, small-molecule inhibitors specific for components of canonical and noncanonical (Ca(2+) and planar cell polarity [PCP]) Wnt pathways, including IWP-2, which blocks Wnt secretion, significantly decreased ehrlichial infection. TRPs directly activated Wnt signaling, as TRP-coated microspheres triggered phagocytosis which was blocked by Wnt pathway inhibitors, demonstrating a key role of TRP activation of Wnt pathways to induce ehrlichial phagocytosis. These novel findings reveal that E. chaffeensis exploits canonical and noncanonical Wnt pathways through TRP effectors to facilitate host cell entry and promote intracellular survival. PMID:26712203

  13. Persistent Ehrlichia chaffeensis infection occurs in the absence of functional major histocompatibility complex class II genes

    NASA Technical Reports Server (NTRS)

    Ganta, Roman Reddy; Wilkerson, Melinda J.; Cheng, Chuanmin; Rokey, Aaron M.; Chapes, Stephen K.

    2002-01-01

    Human monocytic ehrlichiosis is an emerging tick-borne disease caused by the rickettsia Ehrlichia chaffeensis. We investigated the impact of two genes that control macrophage and T-cell function on murine resistance to E. chaffeensis. Congenic pairs of wild-type and toll-like receptor 4 (tlr4)- or major histocompatibility complex class II (MHC-II)-deficient mice were used for these studies. Wild-type mice cleared the infection within 2 weeks, and the response included macrophage activation and the synthesis of E. chaffeensis-specific Th1-type immunoglobulin G response. The absence of a functional tlr4 gene depressed nitric oxide and interleukin 6 secretion by macrophages and resulted in short-term persistent infections for > or =30 days. In the absence of MHC-II alleles, E. chaffeensis infections persisted throughout the entire 3-month evaluation period. Together, these data suggest that macrophage activation and cell-mediated immunity, orchestrated by CD4(+) T cells, are critical for conferring resistance to E. chaffeensis.

  14. Spatial analysis of the distribution of Ehrlichia chaffeensis, causative agent of human monocytotropic ehrlichiosis, across a multi-state region.

    PubMed

    Yabsley, Michael J; Wimberly, Michael C; Stallknecht, David E; Little, Susan E; Davidson, William R

    2005-06-01

    Ehrlichia chaffeensis, which causes human monocytotrophic ehrlichiosis (HME), is an important emerging tick-borne pathogen in the southeastern and southcentral United States. The endemnicity probability of E. chaffeensis and, by implication, locations with risk for HME, was predicted by using two modeling methods. This is first large-scale study to use geospatial analyses to estimate the distribution of E. chaffeensis, and it was conducted using data from a prototypic surveillance system that used white-tailed deer as natural sentinels. Analyses included the E. chaffeensis serostatus for 563 counties from 18 states. Both kriging and logistic regression models provided very reliable portrayals of E. chaffeensis occurrence and predicted that E. chaffeensis distribution had good concordance with human case data. The integration of a deer surveillance system with geospatial analyses was useful in developing HME risk maps that will be useful for identifying high-risk areas for public health interventions such as prevention and control efforts. PMID:15964974

  15. Global proteomic analysis of two tick-borne emerging zoonotic agents: Anaplasma phagocytophilum and Ehrlichia chaffeensis

    SciTech Connect

    Lin, Mingqun ..; Kikuchi, Takane; Brewer, Heather M.; Norbeck, Angela D.; Rikihisa, Yasuko

    2011-02-17

    Anaplasma phagocytophilum and Ehrlichia chaffeensis are obligatory intracellular {alpha}-proteobacteria that infect human leukocytes and cause potentially fatal emerging zoonoses. In the present study, we determined global protein expression profiles of these bacteria cultured in the human promyelocytic leukemia cell line, HL-60. Mass spectrometric (MS) analyses identified a total of 1,212 A. phagocytophilum and 1,021 E. chaffeensis proteins, representing 89.3 and 92.3% of the predicted bacterial proteomes, respectively. Nearly all bacterial proteins ({approx}99%) with known functions were expressed, whereas only approximately 80% of hypothetical proteins were detected in infected human cells. Quantitative MS/MS analyses indicated that highly expressed proteins in both bacteria included chaperones, enzymes involved in biosynthesis and metabolism, and outer membrane proteins, such as A. phagocytophilum P44 and E. chaffeensis P28/OMP-1. Among 113 A. phagocytophilum p44 paralogous genes, 110 of them were expressed and 88 of them were encoded by pseudogenes. In addition, bacterial infection of HL-60 cells up-regulated the expression of human proteins involved mostly in cytoskeleton components, vesicular trafficking, cell signaling, and energy metabolism, but down regulated some pattern recognition receptors involved in innate immunity. Our proteomics data represent a comprehensive analysis of A. phagocytophilum and E. chaffeensis proteomes, and provide a quantitative view of human host protein expression profiles regulated by bacterial infection. The availability of these proteomic data will provide new insights into biology and pathogenesis of these obligatory intracellular pathogens.

  16. Ehrlichia chaffeensis inclusions are early endosomes which selectively accumulate transferrin receptor.

    PubMed Central

    Barnewall, R E; Rikihisa, Y; Lee, E H

    1997-01-01

    Ehrlichia chaffeensis is an obligatory intracellular bacterium which infects macrophages and monocytes. Double immunofluorescence labeling was used to characterize the nature of E. chaffeensis inclusion in the human promyelocytic leukemia cell line THP-1. E. chaffeensis was labeled with dog anti-E. chaffeensis serum and fluorescein isothiocyanate-conjugated anti-dog immunoglobulin G (IgG). Lissamine rhodamine-conjugated anti-mouse IgG was used to label various mouse monoclonal antibodies. Ehrlichial inclusions did not fuse with lysosomes, since they were not labeled with anti-CD63 or anti-LAMP-1. The ehrlichial inclusions were slightly acidic, since they weakly accumulated 3-(2,4-dinitroanilino)-3'-amino-N-methyldipropylamine and stained weakly positive for vacuolar type H+ ATPase. Some ehrlichial inclusions were labeled positive with antibodies against HLA-DR, HLA-ABC, and beta2 microglobulin, while other inclusions in the same cell were labeled negative. The inclusions were labeled strongly positive for transferrin receptors (TfRs) and negative for the clathrin heavy chain. Time course labeling for TfRs showed that up to 3 h postinfection, most of the ehrlichial inclusions were negative for TfRs. After 6 h postinfection, 100% of the ehrlichial inclusions became TfR positive and the intensity of labeling was increased during the subsequent 3 days. Reverse transcription-PCR showed a gradual increase in the level of TfR mRNA postinfection, which reached a peak at 24 h postinfection. These results suggest that ehrlichial inclusions are early endosomes which selectively accumulate TfRs and that the ehrlichiae up-regulate TfR mRNA expression. PMID:9119487

  17. Intravascular persistence of Anaplasma platys, Ehrlichia chaffeensis, and Ehrlichia ewingii DNA in the blood of a dog and two family members

    PubMed Central

    2014-01-01

    Background Anaplasmosis, caused by Anaplasma phagocytophilum and Anaplasma platys, and ehrlichiosis, caused by Ehrlichia chaffeensis, Ehrlichia ewingii, the "Panola Mountain Ehrlichia" and Ehrlichia muris-like pathogens have been identified as emerging tick borne infectious diseases in dogs and human patients. Persistent intravascular infection with these bacteria is well documented in dogs, but is less well documented in human beings. Methods Serology and PCR targeting multiple microbial genes, followed by DNA sequencing, was used to test sequential blood samples. Tissue culture isolation was attempted in two laboratories. Results A. platys, E. chaffeensis, and E. ewingii DNA was amplified from two Anaplasma and Ehrlichia seronegative family members and their dog, all lacking typical symptoms of anaplasmosis or ehrlichiosis. Following treatment with doxycycline, the dog and mother were Anaplasma and Ehrlichia spp. PCR negative. Conclusions Sequential PCR testing provided molecular evidence supporting intravascular persistence of A. platys and Ehrlichia spp. in two humans and their dog. Diagnosticians and clinicians should consider the potential for co-infections due to these tick borne organisms. PMID:24984562

  18. Isolation of Ehrlichia chaffeensis from wild white-tailed deer (Odocoileus virginianus) confirms their role as natural reservoir hosts.

    PubMed Central

    Lockhart, J M; Davidson, W R; Stallknecht, D E; Dawson, J E; Howerth, E W

    1997-01-01

    Field and experimental studies have implicated white-tailed deer (Odocoileus virginianus) as probable reservoir hosts for Ehrlichia chaffeensis, the causative agent of human monocytic ehrlichiosis, but natural infection in deer has not been confirmed through isolation of E. chaffeensis. Thirty-five white-tailed deer collected from three Amblyomma americanum-infested populations in Georgia were examined for evidence of E. chaffeensis infection by serologic, molecular, cell culture, and xenodiagnostic methods. Twenty-seven deer (77%) had E. chaffeensis-reactive indirect fluorescent-antibody assay titers of > or = 1:64; and the blood, spleens, or lymph nodes of seven (20%) deer were positive in a nested PCR assay with E. chaffeensis-specific primers. E. chaffeensis was isolated in DH82 cell cultures from the blood of five (14%) deer, including two deer that were PCR negative. Combination of culture and PCR results indicated that six (17%) deer were probably rickettsemic and that nine (26%) were probably infected. Restriction digestion of PCR products amplified from deer tissues and cell culture isolates resulted in a banding pattern consistent with the E. chaffeensis 16S rRNA gene sequence. The sequences of all PCR products from deer tissues or cell culture isolates were identical to the sequence of the Arkansas type strain of E. chaffeensis. Xenodiagnosis with C3H mice inoculated intraperitoneally with deer blood, spleen, or lymph node suspensions was unsuccessful. When viewed in the context of previous studies, these findings provide strong evidence that E. chaffeensis is maintained in nature primarily by a tick vector-vertebrate reservoir system consisting of lone star ticks and white-tailed deer. PMID:9196173

  19. Isolation and characterization of a new strain of Ehrlichia chaffeensis from a patient with nearly fatal monocytic ehrlichiosis.

    PubMed Central

    Dumler, J S; Chen, S M; Asanovich, K; Trigiani, E; Popov, V L; Walker, D H

    1995-01-01

    Ehrlichia chaffeensis is the causative agent of human monocytic ehrlichiosis, a disease that ranges in severity from asymptomatic infection to death. Only one isolate of E. chaffeensis has been made, the Arkansas strain, upon which all characterizations of the agent of human monocytic ehrlichiosis have been based. We report the isolation and characterization of a new strain of E. chaffeensis, the 91HE17 strain, which was cultivated from a patient with a nearly fatal illness. The new isolate grows best in culture with careful control of pH. The two isolates are nearly identical as determined by light and electron microscopy and have significant antigenic identity in fluorescent-antibody and immunoblot assays using polyclonal antisera and the E. chaffeensis-specific monoclonal antibody 1A9. Isolate 91HE17 had 99.9% nucleotide sequence identity with the Arkansas strain in the 16S rRNA gene. Parts of the Escherichia coli GroE operon homologs had identical restriction enzyme digestion patterns, and a 425-bp region of the GroEL gene had at least 99.8% sequence identity between the E. chaffeensis Arkansas and 91HE17 strains. Isolate 91HE17 lacked an epitope identified in E. chaffeensis Arkansas by the monoclonal antibody 6A1. This new E. chaffeensis isolate is very similar to the Arkansas strain and provides the opportunity to substantiate the existence of diversity among ehrlichiae which infect humans. Specific factors which differ among strains may then be compared to assess their potential contributions toward cellular pathogenicity and ultimately toward the development of disease in humans. PMID:7665632

  20. Habitat factors influencing distributions of Anaplasma phagocytophilum and Ehrlichia chaffeensis in the Mississippi Alluvial Valley.

    PubMed

    Manangan, J S; Schweitzer, S H; Nibbelink, N; Yabsley, M J; Gibbs, S E J; Wimberly, M C

    2007-01-01

    Human monocytotropic ehrlichiosis (HME), caused by the bacterium Ehrlichia chaffeensis, and human granulocytic anaplasmosis (HGA), caused by the bacterium Anaplasma phagocytophilum, are two emerging tick-borne zoonoses of concern. Factors influencing geographic distributions of these pathogens are not fully understood, especially at varying spatial extents (regional versus landscape) and resolutions (counties versus smaller land units). We used logistic regression to compare influences of physical environment, land cover composition, and landscape heterogeneity on distributions of A. phagocytophilum and E. chaffeensis at multiple spatial extents. Pathogen presence or absence was determined from white-tailed deer (Odocoileus virginianus) serum samples collected from 1981 to 2005. Ecological predictor variables were derived from spatial datasets that represented deer density, elevation, land cover, normalized difference vegetation index (NDVI), hydrology, and soil moisture. We used three strategies (a priori, exploratory, and spatial extent) to develop models. Best fitting models were applied within a geographic information system to create predictive probability surfaces for each bacterium. Ecological predictor variables generally resulted in better fitting models for E. chaffeensis than A. phagocytophilum (90.5% and 68% sensitivity, respectively), possibly as a result of differences in the natural histories of tick vectors. Although alternative model development strategies produced different models, in all cases bacteria presence or absence was affected by a combination of soil moisture or flooding variables (thought to affect primarily tick vectors) and forest cover or NDVI variables (thought to affect primarily mammalian hosts). This research demonstrates the potential for modeling the distributions of microscopic tick-borne pathogens using coarse regional datasets and emphasizes the importance of forest cover and flooding as environmental constraints, as well as

  1. Detection of Ehrlichia chaffeensis in adult and nymphal stage lone star ticks (Amblyomma americanum) from Long Island, New York

    USGS Publications Warehouse

    Mixson, T.R.; Ginsberg, H.S.; Campbell, S.R.; Sumner, J.W.; Paddock, C.D.

    2004-01-01

    The lone star tick, Amblyomma americanum (L.), has increased in abundance in several regions of the northeastern United States, including areas of Long Island, NY. Adult and nymphal stage A. americanum collected from several sites on Long Island were evaluated for infection with Ehrlichia chaffeensis, the causative agent of human monocytic ehrlichiosis (HME), by using a nested polymerase chain reaction assay. Fifty-nine (12.5%) of ,17.3 adults and eight of 11.3 pools of five nymphs each (estimated minimum prevalence of infection 1.4%) contained DNA of E. chaffeensis. These data, coupled with the documented expansion of lone star tick populations in the northeastern United States, confirm that E. chaffeensis is endemic to many areas of Long Island and that HME should be considered among the differential diagnoses of the many distinct tick-borne diseases that occur in this region.

  2. Transcription of Ehrlichia chaffeensis Genes Is Accomplished by RNA Polymerase Holoenzyme Containing either Sigma 32 or Sigma 70

    PubMed Central

    Liu, Huitao; Von Ohlen, Tonia; Cheng, Chuanmin; Faburay, Bonto; Ganta, Roman R.

    2013-01-01

    Bacterial gene transcription is initiated by RNA polymerase containing a sigma factor. To understand gene regulation in Ehrlichia chaffeensis, an important tick-transmitted rickettsiae responsible for human monocytic ehrlichiosis, we initiated studies evaluating the transcriptional machinery of several genes of this organism. We mapped the transcription start sites of 10 genes and evaluated promoters of five genes (groE, dnaK, hup, p28-Omp14 and p28-Omp19 genes). We report here that the RNA polymerase binding elements of E. chaffeensis gene promoters are highly homologous for its only two transcription regulators, sigma 32 and sigma 70, and that gene expression is accomplished by either of the transcription regulators. RNA analysis revealed that although transcripts for both sigma 32 and sigma 70 are upregulated during the early replicative stage, their expression patterns remained similar for the entire replication cycle. We further present evidence demonstrating that the organism’s -35 motifs are essential to transcription initiations. The data suggest that E. chaffeensis gene regulation has evolved to support the organism’s growth, possibly to facilitate its intraphagosomal growth. Considering the limited availability of genetic tools, this study offers a novel alternative in defining gene regulation in E. chaffeensis and other related intracellular pathogens. PMID:24278458

  3. Increasing Incidence of Ehrlichiosis in the United States: A Summary of National Surveillance of Ehrlichia chaffeensis and Ehrlichia ewingii Infections in the United States, 2008-2012.

    PubMed

    Nichols Heitman, Kristen; Dahlgren, F Scott; Drexler, Naomi A; Massung, Robert F; Behravesh, Casey Barton

    2016-01-01

    Human ehrlichiosis is a potentially fatal disease caused by Ehrlichia chaffeensis and Ehrlichia ewingii. Cases of ehrlichiosis are reported to Centers for Disease Control and Prevention through two national surveillance systems: Nationally Notifiable Diseases Surveillance System (NNDSS) and Case Report Forms. During 2008-2012, 4,613 cases of E. chaffeensis infections were reported through NNDSS. The incidence rate (IR) was 3.2 cases per million person-years (PYs). The hospitalization rate (HR) was 57% and the case fatality rate (CFR) was 1%. Children aged < 5 years had the highest CFR of 4%. During 2008-2012, 55 cases of E. ewingii infection were reported through NNDSS. The national IR was 0.04 cases per million PY. The HR was 77%; no deaths were reported. Immunosuppressive conditions were reported by 26% of cases. The overall rate for ehrlichiosis has increased 4-fold since 2000. Although previous literature suggests E. ewingii primarily affects those who are immunocompromised, this report shows most cases occurred among immunocompetent patients. This is the first report to show children aged < 5 years with ehrlichiosis have an increased CFR, relative to older patients. Ongoing surveillance and reporting of tick-borne diseases are critical to inform public health practice and guide disease treatment and prevention efforts. PMID:26621561

  4. Anti-Ehrlichia chaffeensis antibody complexed with E. chaffeensis induces potent proinflammatory cytokine mRNA expression in human monocytes through sustained reduction of IkappaB-alpha and activation of NF-kappaB.

    PubMed Central

    Lee, E H; Rikihisa, Y

    1997-01-01

    Ehrlichia chaffeensis is an obligatory intracellular bacterium that infects monocytes and macrophages and is the etiologic agent of human ehrlichiosis in the United States. Our previous studies showed that the exposure of human monocytes to E. chaffeensis induces the expression of interleukin-1beta (IL-1beta), IL-8, and IL-10 genes in vitro but not the expression of tumor necrosis factor alpha (TNF-alpha) and IL-6 mRNAs. In this study, the effect of anti-E. chaffeensis antibody complexed with E. chaffeensis on the expression of major proinflammatory cytokines in human monocytes was examined. Human monocytic cell line THP-1 was treated with E. chaffeensis which had been preincubated with human anti-E. chaffeensis serum for 2 h, and the levels of cytokine mRNAs were evaluated by competitive reverse transcription-PCR. Anti-E. chaffeensis antibody complexed with E. chaffeensis significantly enhanced mRNA expression of IL-1beta in THP-1 cells. The expression of TNF-alpha and IL-6 mRNAs was also induced. The levels of secreted IL-1beta, TNF-alpha, and IL-6 during 24 h of stimulation were comparable to those induced by Escherichia coli lipopolysaccharide at 1 microg/ml. Fab fragment of anti-E. chaffeensis immunoglobulin G complexed with E. chaffeensis did not induce any of these three cytokines, indicating that ehrlichial binding is required for IL-1beta mRNA expression and that binding of the immune complex to the Fc gamma receptor is required for TNF-alpha and IL-6 mRNA expression and enhanced IL-1beta mRNA expression. Furthermore, prolonged degradation of IkappaB-alpha and activation of NF-kappaB were demonstrated in THP-1 cells exposed to anti-E. chaffeensis serum and E. chaffeensis. This result implies that development of anti-E. chaffeensis antibody in patients can result in the production of major proinflammatory cytokines, which may play an important role in the pathophysiology of ehrlichiosis and immune responses to it. PMID:9199464

  5. Ehrlichia chaffeensis Proliferation Begins with NtrY/NtrX and PutA/GlnA Upregulation and CtrA Degradation Induced by Proline and Glutamine Uptake

    PubMed Central

    Cheng, Zhihui; Lin, Mingqun

    2014-01-01

    ABSTRACT How the obligatory intracellular bacterium Ehrlichia chaffeensis begins to replicate upon entry into human monocytes is poorly understood. Here, we examined the potential role of amino acids in initiating intracellular replication. PutA converts proline to glutamate, and GlnA converts glutamate to glutamine. E. chaffeensis PutA and GlnA complemented Escherichia coli putA and glnA mutants. Methionine sulfoximine, a glutamine synthetase inhibitor, inhibited E. chaffeensis GlnA activity and E. chaffeensis infection of human cells. Incubation of E. chaffeensis with human cells rapidly induced putA and glnA expression that peaked at 24 h postincubation. E. chaffeensis took up proline and glutamine but not glutamate. Pretreatment of E. chaffeensis with a proline transporter inhibitor (protamine), a glutamine transporter inhibitor (histidine), or proline analogs inhibited E. chaffeensis infection, whereas pretreatment with proline or glutamine enhanced infection and upregulated putA and glnA faster than no treatment or glutamate pretreatment. The temporal response of putA and glnA expression was similar to that of NtrY and NtrX, a two-component system, and electrophoretic mobility shift assays showed specific binding of recombinant E. chaffeensis NtrX (rNtrX) to the promoter regions of E. chaffeensis putA and glnA. Furthermore, rNtrX transactivated E. chaffeensis putA and glnA promoter-lacZ fusions in E. coli. Growth-promoting activities of proline and glutamine were also accompanied by rapid degradation of the DNA-binding protein CtrA. Our results suggest that proline and glutamine uptake regulates putA and glnA expression through NtrY/NtrX and facilitates degradation of CtrA to initiate a new cycle of E. chaffeensis growth. PMID:25425236

  6. Attenuated Mutants of Ehrlichia chaffeensis Induce Protection against Wild-Type Infection Challenge in the Reservoir Host and in an Incidental Host

    PubMed Central

    Nair, Arathy D. S.; Cheng, Chuanmin; Jaworski, Deborah C.; Ganta, Suhasini; Sanderson, Michael W.

    2015-01-01

    Ehrlichia chaffeensis, a tick-borne rickettsial organism, causes the disease human monocytic ehrlichiosis. The pathogen also causes disease in several other vertebrates, including dogs and deer. In this study, we assessed two clonally purified E. chaffeensis mutants with insertions within the genes Ech_0379 and Ech_0660 as vaccine candidates in deer and dogs. Infection with the Ech_0379 mutant and challenge with wild-type E. chaffeensis 1 month following inoculation with the mutant resulted in the reduced presence of the organism in blood compared to the presence of wild-type infection in both deer and dogs. The Ech_0660 mutant infection resulted in its rapid clearance from the bloodstream. The wild-type infection challenge following Ech_0660 mutant inoculation also caused the pathogen's clearance from blood and tissue samples as assessed at the end of the study. The Ech_0379 mutant-infected and -challenged animals also remained positive for the organism in tissue samples in deer but not in dogs. This is the first study that documents that insertion mutations in E. chaffeensis that cause attenuated growth confer protection against wild-type infection challenge. This study is important in developing vaccines to protect animals and people against Ehrlichia species infections. PMID:25916990

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2016-01-01

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

  9. Vaccination with an Attenuated Mutant of Ehrlichia chaffeensis Induces Pathogen-Specific CD4+ T Cell Immunity and Protection from Tick-Transmitted Wild-Type Challenge in the Canine Host

    PubMed Central

    McGill, Jodi L.; Nair, Arathy D. S.; Cheng, Chuanmin; Rusk, Rachel A.; Jaworski, Deborah C.; Ganta, Roman R.

    2016-01-01

    Ehrlichia chaffeensis is a tick-borne rickettsial pathogen and the causative agent of human monocytic ehrlichiosis. Transmitted by the Amblyomma americanum tick, E. chaffeensis also causes disease in several other vertebrate species including white-tailed deer and dogs. We have recently described the generation of an attenuated mutant strain of E. chaffeensis, with a mutation in the Ech_0660 gene, which is able to confer protection from secondary, intravenous-administered, wild-type E. chaffeensis infection in dogs. Here, we extend our previous results, demonstrating that vaccination with the Ech_0660 mutant protects dogs from physiologic, tick-transmitted, secondary challenge with wild-type E. chaffeensis; and describing, for the first time, the cellular and humoral immune responses induced by Ech_0660 mutant vaccination and wild-type E. chaffeensis infection in the canine host. Both vaccination and infection induced a rise in E. chaffeensis-specific antibody titers and a significant Th1 response in peripheral blood as measured by E. chaffeensis antigen-dependent CD4+ T cell proliferation and IFNγ production. Further, we describe for the first time significant IL-17 production by peripheral blood leukocytes from both Ech_0660 mutant vaccinated animals and control animals infected with wild-type E. chaffeensis, suggesting a previously unrecognized role for IL-17 and Th17 cells in the immune response to rickettsial pathogens. Our results are a critical first step towards defining the role of the immune system in vaccine-induced protection from E. chaffeensis infection in an incidental host; and confirm the potential of the attenuated mutant clone, Ech_0660, to be used as a vaccine candidate for protection against tick-transmitted E. chaffeensis infection. PMID:26841025

  10. Use of Peptide-Based Enzyme-Linked Immunosorbent Assay followed by Immunofluorescence Assay To Document Ehrlichia chaffeensis as a Cause of Febrile Illness in Nicaragua.

    PubMed

    Chikeka, Ijeuru; Matute, Armando J; Dumler, J Stephen; Woods, Christopher W; Mayorga, Orlando; Reller, Megan E

    2016-06-01

    Ehrlichia chaffeensis, the etiologic agent of human monocytic ehrlichiosis (HME), has been extensively studied as a cause of acute febrile illness and an emerging tick-borne zoonosis in the United States. Limited data suggest its presence in other regions, including Central and South America but not Nicaragua to date. Diagnosis of E. chaffeensis infection by indirect immunofluorescence assay (IFA) is the reference standard due to its presumed high sensitivity and specificity, but IFA is impractical, variably reproducible, and cumbersome for large epidemiologic studies and for clinical diagnosis in resource-poor regions. We evaluated a high-throughput, objective peptide-based enzyme-linked immunosorbent assay (ELISA) for use alone or in combination with IFA. We found that it performed best as a screening test (sensitivity, 100%; specificity, 84%) to reduce the proportion of serum samples that were required by the more cumbersome and subjective IFA testing to <20%. Using a two-step diagnostic approach (IFA is performed if the ELISA is positive), we identified E. chaffeensis or a serologically and antigenically similar organism as a heretofore unrecognized cause of acute febrile illness in humans in Nicaragua and demonstrated the utility of the peptide ELISA as a screening tool for large-scale clinical studies. PMID:27053675

  11. New species of Ehrlichia isolated from Rhipicephalus (Boophilus) microplus shows an ortholog of the E. canis major immunogenic glycoprotein gp36 with a new sequence of tandem repeats

    PubMed Central

    2012-01-01

    Background Ehrlichia species are the etiological agents of emerging and life-threatening tick-borne human zoonoses that inflict serious and fatal infections in companion animals and livestock. The aim of this paper was to phylogeneticaly characterise a new species of Ehrlichia isolated from Rhipicephalus (Boophilus) microplus from Minas Gerais, Brazil. Methods The agent was isolated from the hemolymph of Rhipicephalus (B.) microplus engorged females that had been collected from naturally infested cattle in a farm in the state of Minas Gerais, Brazil. This agent was then established and cultured in IDE8 tick cells. The molecular and phylogenetic analysis was based on 16S rRNA, groEL, dsb, gltA and gp36 genes. We used the maximum likelihood method to construct the phylogenetic trees. Results The phylogenetic trees based on 16S rRNA, groEL, dsb and gltA showed that the Ehrlichia spp isolated in this study falls in a clade separated from any previously reported Ehrlichia spp. The molecular analysis of the ortholog of gp36, the major immunoreactive glycoproteins in E. canis and ortholog of the E. chaffeensis gp47, showed a unique tandem repeat of 9 amino acids (VPAASGDAQ) when compared with those reported for E. canis, E. chaffeensis and the related mucin-like protein in E. ruminantium. Conclusions Based on the molecular and phylogenetic analysis of the 16S rRNA, groEL, dsb and gltA genes we concluded that this tick-derived microorganism isolated in Brazil is a new species, named E. mineirensis (UFMG-EV), with predicted novel antigenic properties in the gp36 ortholog glycoprotein. Further studies on this new Ehrlichia spp should address questions about its transmissibility by ticks and its pathogenicity for mammalian hosts. PMID:23231731

  12. Rural Residents in China Are at Increased Risk of Exposure to Tick-Borne Pathogens Anaplasma phagocytophilum and Ehrlichia chaffeensis

    PubMed Central

    Zhang, Lijuan; Liu, Hong; Xu, Bianli; Zhang, Zhilun; Jin, Yuming; Li, Weiming; Lu, Qunying; Li, Liang; Chang, Litao; Zhang, Xiuchun; Fan, Desheng; Cao, Minghua; Bao, Manli; Zhang, Ying; Guan, Zengzhi; Cheng, Xueqin; Tian, Lina; Wang, Shiwen; Yu, Huilan; Yu, Qiang; Wang, Yong; Zhang, Yonggen; Tang, Xiaoyan; Yin, Jieying; Lao, Shijun; Wu, Bin; Li, Juan; Li, Weihong; Xu, Qiyi; Shi, Yonglin; Huang, Fang

    2014-01-01

    As emerging tick born rickettsial diseases caused by A. phagocytophilum and E. chaffeensis, anaplasmosis and ehrlichiosis have become a serious threat to human and animal health throughout the world. In particular, in China, an unusual transmission of nosocomial cases of human granulocytic anaplasmosis occurred in Anhui Province in 2006 and more recent coinfection case of A. phagocytophilum and E. chaffeensis was documented in Shandong Province. Although the seroprevalence of human granulocytic anaplasmosis (former human granulocytic ehrlichiosis, HGE) has been documented in several studies, these data existed on local investigations, and also little data was reported on the seroprevalence of human monocytic ehrlichiosis (HME) in China. In this cross-sectional epidemiological study, indirect immunofluorescence antibody assay (IFA) proposed by WHO was used to detect A. phagocytophilum and E. chaffeensis IgG antibodies for 7,322 serum samples from agrarian residents from 9 provinces/cities and 819 urban residents from 2 provinces. Our data showed that farmers were at substantially increased risk of exposure. However, even among urban residents, risk was considerable. Seroprevalence of HGA and HME occurred in diverse regions of the country and tended to be the highest in young adults. Many species of ticks were confirmed carrying A. phagocytophilum organisms in China while several kinds of domestic animals including dog, goats, sheep, cattle, horse, wild rabbit, and some small wild rodents were proposed to be the reservoir hosts of A. phagocytophilum. The broad distribution of vector and hosts of the A. phagocytophilum and E. chaffeensis, especially the relationship between the generalized susceptibility of vectors and reservoirs and the severity of the disease's clinical manifestations and the genetic variation of Chinese HGA isolates in China, is urgently needed to be further investigated. PMID:24877080

  13. Migratory and carnivorous birds in Brazil: reservoirs for Anaplasma and Ehrlichia species?

    PubMed

    Machado, Rosangela Zacarias; André, Marcos Rogério; Werther, Karin; de Sousa, Eliane; Gavioli, Fernando Antônio; Alves Junior, José Roberto Ferreira

    2012-08-01

    In order to investigate new hosts for Anaplasmataceae agents in Brazil, we collected blood samples from 21 wild birds. Using molecular techniques, we detected the presence of Anaplasma phagocytophilum, Ehrlichia chaffeensis, and an Ehrlichia species closely related to Ehrlichia canis in carnivorous avian blood samples. In addition, an Ehrlichia species closely related to an Ehrlichia species found in wild felines in Brazil was also detected in a goose blood sample. Wild birds may play a role as carriers of Anaplasmataceae agents in Brazil. PMID:22607070

  14. Molecular and serologic evidence of tick-borne Ehrlichiae in three species of lemurs from St. Catherines Island, Georgia, USA.

    PubMed

    Yabsley, Michael J; Norton, Terry M; Powell, Malcolm R; Davidson, William R

    2004-12-01

    In recent years, several species of ehrlichiae have been recognized as tick-borne disease agents of veterinary and medical importance. Clinically normal free-ranging or previously free-ranging lemurs, including 46 ring-tailed lemurs (Lemur catta), six blue-eyed black lemurs (Eulemur macaco flavifrons), and four black and white ruffed lemurs (Varecia variegata variegata) from St. Catherines Island, Georgia, were tested for evidence of exposure to tick-borne ehrlichiae. All 52 adult lemurs were serologically tested for exposure to Ehrlichia chaffeensis and Anaplasma phagocytophilum. Polymerase chain reaction (PCR) assays for E. chaffeensis, A. phagocytophilum, Ehrlichia ewingii, and Ehrlichia canis were conducted on blood samples from all 56 lemurs. Blood from all lemurs was inoculated into DH82 cell cultures for E. chaffeensis isolation. Of the adult lemurs, 20 (38.5%) and 16 (30.8%) had antibodies reactive (> or =1:128) for E. chaffeensis and A. phagocytophilum, respectively. Two ring-tailed lemurs were PCR and culture positive for E. chaffeensis. Molecular characterization of the two E. chaffeensis isolates showed that both contained 5-repeat variants of the variable-length PCR target (VLPT) antigen gene and 3-repeat variants of the 120-kDa antigen gene. Sequencing of the VLPT genes revealed a novel amino acid repeat unit (type-9). One lemur infected with E. chaffeensis was slightly hypoproteinemic and had moderately elevated serum alanine aminotransferase (ALT) levels. These lemurs from St. Catherines Island have been exposed to or infected with tick-borne ehrlichiae, or both, but showed no clinical disease. PMID:15732591

  15. Antibodies reactive with Ehrlichia canis, Ehrlichia phagocytophila genogroup antigens and the spotted fever group rickettsial antigens, in free-ranging jackals (Canis aureus syriacus) from Israel.

    PubMed

    Waner, T; Baneth, G; Strenger, C; Keysary, A; King, R; Harrus, S

    1999-03-31

    A seroepidemiological survey was conducted to investigate the prevalence of antibodies reactive with the Ehrlichia canis and Ehrlichia phagocytophila genogroup antigens, and the spotted fever group (SFG) rickettsiae antigens in jackals in Israel (Canis aureus syriacus), to assess the possible role of the jackal in the epidemiology of these diseases. Fifty-three serum samples from jackals were assayed by the indirect immunofluorescence antibody test. Antibodies to E. canis were detected in 35.8% serum samples while 26.4% of the samples tested were positive to Ehrlichia chaffeensis. Twenty-six percent of the jackals tested were seropositive to E. phagocytophila, of which 5.7% were seropositive to E. phagocytophila alone without any seroreactivity to either E. canis or E. chaffeensis. Fifty-five percent of the jackals were seropositive to the SFG-rickettsiae antigens. The results suggest a high exposure rate of jackals in Israel to E. canis. Positive reactivity to E. chaffeensis was considered to be due to antigenic cross-reactions with E. canis. The study demonstrated for the first time the presence of E. phagocytophila antibodies in free-range jackals. The high incidence of antibodies to the SFG-rickettsiae and their relatively high antibody titers was suggestive of either recent or persistent infection. The possibility that jackals may play a role in the transmission of E. canis, E. phagocytophila and the SFG-rickettsiae for human and canine infections is discussed. PMID:10321583

  16. Detection of genotype-specific Ehrlichia canis exposure in Brazilian dogs by TRP36 peptide ELISA.

    PubMed

    Aguiar, Daniel M; Zhang, Xiaofeng; Braga, Isis A; Taques, Isis I G G; McBride, Jere W

    2016-02-01

    We recently characterized a novel genotype of Ehrlichia canis based on the tandem repeat (TR) sequence of the TRP36 gene in Brazil. The TR amino acid sequence of the Brazilian (Br) genotype (ASVVPEAE) was divergent from the previously described US genotype (TEDSVSAPA) of E. canis. In this study, we developed an ELISA based on TRP36 TR synthetic peptides from both Br and US E. canis TRP36 genotypes to serologically detect and distinguish infections caused by these genotypes. Sera from 30 Brazilian dogs naturally infected with E. canis, sera from dogs experimentally infected E. canis (Jake and Cuiabá #1 strains) and E. chaffeensis (Arkansas strain) and 12 seronegative E. canis dogs were evaluated. Fifteen naturally infected Brazilian dogs had antibodies that reacted with the US TRP36 (n=9) or Br TRP36 (n=6) only, and 13 dogs had antibodies that reacted with both TPR36 peptides suggesting that these dogs were exposed to both genotypes. Most dogs (n=28) had antibodies that reacted with the highly conserved E. canis TRP19 peptide; however, two dogs had antibodies to E. canis TRP19, but did not have TRP36 antibodies, raising the possibility that another novel TRP36 genotype is circulating in Brazil. Our results demonstrate that synthetic peptides based on the TR region of E. canis TRP36 can be used to serologically distinguish infections or identify coinfections by different genotypes, and to determine the seroprevalence of various E. canis genotypes in Brazil. PMID:26482949

  17. Ehrlichia Meningitis Mimicking Aneurysmal Subarachnoid Hemorrhage

    PubMed Central

    Dredla, Brynn

    2015-01-01

    Thunderclap headache is a sudden and severe headache that can occur after an aneurysmal subarachnoid hemorrhage (SAH). Subarachnoid hemorrhage is a medical emergency that requires prompt attention and hospitalization. Patients with thunderclap headache often undergo a noncontrast head computed tomography (CT) scan to ascertain SAH bleeding and, if the scan is negative, then undergo a lumbar puncture to look for cerebrospinal fluid (CSF) red blood cells (RBCs), which would be consistent with an aneurysmal leak. If the initial CT is negative and CSF is positive for RBCs, patients are usually admitted to the hospital for evaluation of intracranial aneurysm. We encountered a patient with thunderclap headache whose initial head CT was negative for SAH and whose CSF tested positive for RBCs. The patient was referred to our center for evaluation and management of aneurysmal SAH. However, on careful review of the patient’s medical history, serum laboratory values, and spinal fluid values, the patient was diagnosed with Ehrlichia chaffeensis meningitis. While Ehrlichia meningitis is rare, it is important to recognize the clinical clues that could help avoid formal cerebral angiography, a costly and potentially unnecessary procedure. We present how this case represented a cognitive framing bias and anchoring heuristic as well as steps that medical providers can use to prevent such cognitive errors in diagnosis. PMID:27053985

  18. Detection of Borrelia, Ehrlichia, and Rickettsia spp. in ticks in northeast Missouri.

    PubMed

    Hudman, D A; Sargentini, N J

    2016-07-01

    We evaluated Amblyomma americanum (lone star tick) and Dermacentor variabilis (American dog tick) in northeast Missouri for the presence of Borrelia, Ehrlichia, and Rickettsia bacteria. We collected actively questing ticks from four sites within Adair County, Missouri. A total of 15,162 ticks were collected, of which 13,980 were grouped in 308 pools (lone star ticks, 288 pools; American dog ticks, 20 pools) and tested for presence/absence of bacteria using polymerase chain reaction. Infection rates were calculated as the maximum likelihood estimation (MLE) with 95% confidence intervals (CI). Of the 308 pools tested, 229 (74.4%) were infected with bacteria and the overall MLE of the infection rate per 100 ticks was calculated as 2.9% (CI 2.61-3.21). Infection rates varied among life stages, 28.6% (CI 23.89-33.97) in adults, 7.0% (CI 5.10-9.86) in nymphs, and 1.0% (CI 0.75-1.20) in larvae. In the 116 adult lone star pools, infection rates were calculated for Borrelia lonestari (1.4%), Borrelia spp. (2.7%), Ehrlichia chaffeensis (6.1%), Ehrlichia ewingii (3.3%), Rickettsia amblyommii (18.3%), and Rickettsia montanensis (0.4%). Infection rates for the 52 nymphal lone star pools were calculated as B. lonestari (1.03%), Borrelia spp. (0.40%), E. chaffeensis (2.02%), E. ewingii (0.24%), and R. amblyommii (2.70%). In the 20 adult American dog tick pools, infection rates were determined as E. chaffeensis (9.47%), E. ewingii (5.47%), and R. montanensis (8.06%). Eight Borrelia samples were sequenced with five 99-100% identical to B. burgdorferi (s.l.) and three 99% identical to B. lonestari. Eight samples were sequenced for E. chaffeensis (all 99-100% identical) and one sample was sequenced for E. ewingii (99% identical). Seven samples were sequenced for Rickettsia and three were 99% identical to R. montanensis and four were 100% identical to R. amblyommii. This study demonstrates B. lonestari, E. chaffeensis, E. ewingii, R. amblyommii, and R. montanensis in northeast

  19. Survey of Ticks Collected from Tennessee Cattle and Their Pastures for Anaplasma and Ehrlichia Species.

    PubMed

    Pompo, K; Mays, S; Wesselman, C; Paulsen, D J; Fryxell, R T Trout

    2016-02-01

    Anaplasma marginale is the causative agent for bovine anaplasmosis (BA) and Ehrlichia ruminantium is the causative agent for heartwater, 2 devastating diseases of cattle. BA is common in the United States and frequently reported in western Tennessee cattle; however, cases of heartwater are not yet established in the continental United States. Because both pathogens are transmitted via the bites of infected ticks, the objective of this study was to survey cattle and pastures for ticks and for each pathogen. University of Tennessee AgResearch has 7 research and education centers (REC) located throughout the state at which they manage cattle. Ticks were collected from selected cattle (every fourth to sixth animal) and pastures (via dragging) associated with the herd from each REC during the summer of 2013. A total of 512 ticks were collected from cattle (n = 386) and pastures (n = 126) and were PCR-screened for Anaplasma and Ehrlichia using genus-specific primers. Collections consisted of 398 (77.7%) Amblyomma americanum, 84 (16.4%) Amblyomma maculatum, and 30 (5.9%) Dermacentor variabilis. Ticks were not recovered from pastures or cattle east of the Tennessee Plateau. The North American vectors for An. marginale and E. ruminantium were identified (D. variabilis and A. maculatum, respectively), but neither pathogen was recovered. A large proportion of ticks were collected from cattle and, of these, a majority were attached to their host (compared to questing on their host or engorged on the host). Four A. americanum were positive for Ehrlichia spp. (Ehrlichia ewingii, Ehrlichia chaffeensis, and Panola Mountain Ehrlichia), all in western Tennessee. With the identification of a few Ehrlichia infections in cattle-associated ticks and current A. marginale rates in Tennessee beef cattle nearing 11%, additional research is needed to establish baseline tick, Anaplasma, and Ehrlichia data for future management studies. PMID:26348980

  20. Prevalence of Ehrlichia, Borrelia, and Rickettsial agents in Amblyomma americanum (Acari : Ixodidae) collected from nine states

    USGS Publications Warehouse

    Mixson, T.R.; Campbell, S.R.; Gill, J.S.; Ginsberg, H.S.; Reichard, M.V.; Schultz, T.L.; Dasch, G.A.

    2006-01-01

    Ambyomma antericanum (L.) (Acari: Ixodidae) is an aggressive tick that feeds on humans during all postembryonic life stages. In many regions of the United States, it is the tick most commonly found attached to humans. Public health interest has grown recently, due to the recognition of new human pathogens transmitted by A. antericanum and the expanding distribution of the tick. A. americanum is a vector of several bacteria pathogenic to humans. Ehrlichia chaffeensis and Ehrlichia ewingii cause moderate-to-severe febrile illness. 'Rickettsia amblyommii,' a member of the spotted fever group Rickettsia, also has recently been implicated as a possible human pathogen based on serologic evidence from persons recovering from illness after a tick bite. We have determined the prevalence of infection of Ehrlichia chaffeensis, E. ewingii, 'Borrelia lonestari,' and R. amblyommii within A. americanum ticks from 29 sites in nine states. Overall infection prevalences were 4.7% for E. chaffeensis (range, 0-27%), 3.5% for E. ewingii (range, 0-18.6%), 2.5% for B. lonestari (range, 0-12.2%), and 41.2% for R. amblyommii (range, 0-84.0%). In addition, 87 ticks (4.3%) were infected with two or more bacteria. This report documents new distribution records for E. ewingii, B. lonestari, and R. amblyommii and underscores the nonhomogeneous distribution of pathogen foci of infection. Additional surveillance throughout the range of A. antericanum is warranted to increase physician and public awareness of the risk of disease to humans from exposure to the agents transmitted by this tick.

  1. Immunodiagnosis of Ehrlichia canis Infection with Recombinant Proteins

    PubMed Central

    McBride, Jere W.; Corstvet, Richard E.; Breitschwerdt, Edward B.; Walker, David H.

    2001-01-01

    Ehrlichia canis causes a potentially fatal rickettsial disease of dogs that requires rapid and accurate diagnosis in order to initiate appropriate therapy leading to a favorable prognosis. We recently reported the cloning of two immunoreactive E. canis proteins, P28 and P140, that were applicable for serodiagnosis of the disease. In the present study we cloned a new immunoreactive E. canis surface protein gene of 1,170 bp, which encodes a protein with a predicted molecular mass of 42.6 kDa (P43). The P43 gene was not detected in E. chaffeensis DNA by Southern blot, and antisera against recombinant P43 (rP43) did not react with E. chaffeensis as detected by indirect fluorescent antibody (IFA) assay. Forty-two dogs exhibiting signs and/or hematologic abnormalities associated with canine ehrlichiosis were tested by IFA assay and by recombinant Western immunoblot. Among the 22 samples that were IFA positive for E. canis, 100% reacted with rP43, 96% reacted with rP28, and 96% reacted with rP140. The specificity of the recombinant proteins compared to the IFAs was 96% for rP28, 88% for P43 and 63% for P140. The results of this study demonstrate that the rP43 and rP28 are sensitive and reliable serodiagnostic antigens for E. canis infections. PMID:11136790

  2. Current management of human granulocytic anaplasmosis, human monocytic ehrlichiosis and Ehrlichia ewingii ehrlichiosis

    PubMed Central

    Thomas, Rachael J; Stephen Dumler, J; Carlyon, Jason A

    2009-01-01

    Anaplasma phagocytophilum, Ehrlichia chaffeensis and Ehrlichia ewingii are emerging tick-borne pathogens and are the causative agents of human granulocytic anaplasmosis, human monocytic ehrlichiosis and E. ewingii ehrlichiosis, respectively. Collectively, these are referred to as human ehrlichioses. These obligate intracellular bacterial pathogens of the family Anaplasmataceae are transmitted by Ixodes spp. or Amblyomma americanum ticks and infect peripherally circulating leukocytes to cause infections that range in clinical spectra from asymptomatic seroconversion to mild, severe or, in rare instances, fatal disease. This review describes: the ecology of each pathogen; the epidemiology, clinical signs and symptoms of the human diseases that each causes; the choice methods for diagnosing and treating human ehrlichioses; recommendations for patient management; and is concluded with suggestions for potential future research. PMID:19681699

  3. Molecular identification of Ehrlichia species and host bloodmeal source in Amblyomma americanum L. from two locations in Tennessee, United States.

    PubMed

    Harmon, Jessica R; Scott, M Cathy; Baker, Ellen M; Jones, Carl J; Hickling, Graham J

    2015-04-01

    The current status of tick-borne diseases in the southeastern United States is challenging to define due to emerging pathogens, uncertain tick/host relationships, and changing disease case definitions. A golf-oriented retirement community on the Cumberland Plateau in Tennessee experienced an ehrlichiosis outbreak in 1993, prompting efforts to reduce the local tick population using '4-Poster' acaricide devices targeting white-tailed deer (Odocoileus virginianus). In 2009, the prevalence of Ehrlichia spp. in questing ticks was surveyed in the area and compared to a Tennessee state park where acaricide had not been applied. The range of wildlife hosts that immature Amblyomma americanum fed upon and the role that these hosts may play in pathogen dynamics were investigated using a reverse line blot (RLB) bloodmeal analysis technique. Amblyomma americanum was by far the most common tick species in both study areas (>99% of ticks collected). Of 303 adult and nymphal A. americanum tested at the retirement community, six were positive for Ehrlichia chaffeensis (2.0%), 16 were positive for E. ewingii (5.3%), and six were positive for Panola Mountain Ehrlichia (2.0%). This is the first confirmation of Panola Mountain Ehrlichia in A. americanum from the state of Tennessee. The 9.3% prevalence of Ehrlichia spp. in ticks from the retirement community was similar to that detected at the state park site (5.5%), suggesting that the 4-Poster treatment had not been sufficient to reduce Ehrlichia spp. cycling in the tick population. At both study sites, A. americanum fed on a wide range of mammal and bird species, with a minority of detectable bloodmeals coming from deer. Of the Ehrlichia-infected nymphs with positive bloodmeal identification, none fed on deer, indicating that multiple vertebrate species are contributing to sylvatic maintenance of Ehrlichia spp. at these sites. This highlights the difficulty of attempting to reduce the risk of tick-borne disease through host

  4. Absence of antibodies to Rickettsia spp., Bartonella spp., Ehrlichia spp. and Coxiella burnetii in Tahiti, French Polynesia

    PubMed Central

    2014-01-01

    Abtract Background In the Pacific islands countries and territories, very little is known about the incidence of infectious diseases due to zoonotic pathogens. To our knowledge, human infections due to Rickettsia spp., Coxiella burnetii, Ehrlichia spp. and Bartonella spp. have never been reported in French Polynesia; and infections due to C. burnetti have been reported worldwide except in New Zealand. To evaluate the prevalence of this disease, we conducted a serosurvey among French Polynesian blood donors. Methods The presence of immunoglobulin G antibodies against R. felis, R. typhi, R. conorii, C. burnetii, B. henselae, B. quintana, and E. chaffeensis was evaluated by indirect immunofluorescence assay in sera from 472 French Polynesian blood donors collected from 2011 to 2013. In addition, 178 ticks and 36 cat fleas collected in French Polynesia were also collected and tested by polymerase chain reaction to detect Rickettsia spp., B. henselae and Ehrlichia spp. Results None of the blood donors had antibodies at a significant level against Rickettsia spp., Coxiella burnetii, Ehrlichia spp. and Bartonella spp. All tested ticks and cat fleas were PCR-negative for Rickettsia spp., B. henselae, and Ehrlichia spp. Conclusion We cannot conclude that these pathogens are absent in French Polynesia but, if present, their prevalence is probably very low. C. burnetii has been reported worldwide except in New Zealand. It may also be absent from French Polynesia. PMID:24885466

  5. Vector-Borne Diseases in Stray Dogs in Peninsular Malaysia and Molecular Detection of Anaplasma and Ehrlichia spp. from Rhipicephalus sanguineus (Acari: Ixodidae) Ticks.

    PubMed

    Koh, Fui Xian; Panchadcharam, Chandrawathani; Tay, Sun Tee

    2016-01-01

    Little data are available on the prevalence and transmission of vector-borne diseases in stray dogs in Peninsular Malaysia. This study was designed to determine the occurrence of vector-borne pathogens in Malaysian stray dogs using serological and molecular approaches. In total, 48 dog blood samples were subjected to serological analysis using SNAP 4Dx kit (IDEXX Laboratories, Westbrook, ME). The presence of Ehrlichia and Anaplasma DNA in the dog blood samples and Rhipicephalus sanguineus (Latreille) ticks was detected using nested polymerase chain reaction assays. Positive serological findings against Ehrlichia canis and Anaplasma phagocytophilum were obtained in 17 (39.5%) and four (9.3%) of 43 dog samples, respectively. None of the dog blood samples were positive for Borrelia burgdorferi and Dirofilaria immitis. DNA of E. canis and A. phagocytophilum was detected in 12 (25.5%) and two (4.3%) of 47 dog blood samples, and 17 (51.5%) and one (3.0%) of 33 R. sanguineus ticks, respectively. Additionally, DNA of Ehrlichia spp. closely related to Ehrlichia chaffeensis was detected in two (6.1%) R. sanguineus ticks. This study highlights the prevalence of anaplasmosis and ehrlichiosis in dogs in Malaysia. Due to the zoonotic potential of Ehrlichia and Anaplasma spp., appropriate measures should be instituted for prevention and control of vector-borne diseases in dogs. PMID:26494821

  6. Detection of Ehrlichia spp., Anaplasma spp., Rickettsia spp., and other eubacteria in ticks from the Thai-Myanmar border and Vietnam.

    PubMed

    Parola, Philippe; Cornet, Jean-Paul; Sanogo, Yibayiri Osée; Miller, R Scott; Thien, Huynh Van; Gonzalez, Jean-Paul; Raoult, Didier; Telford III, Sam R; Wongsrichanalai, Chansuda

    2003-04-01

    A total of 650 ticks, including 13 species from five genera, were collected from animals, from people, or by flagging of the vegetation at sites on the Thai-Myanmar border and in Vietnam. They were tested by PCR to detect DNA of bacteria of the order RICKETTSIALES: Three Anaplasma spp. were detected in ticks collected in Thailand, including (i) Anaplasma sp. strain AnDa465, which was considered a genotype of Anaplasma platys (formerly Ehrlichia platys) and which was obtained from Dermacentor auratus ticks collected from dogs; (ii) Anaplasma sp. strain AnAj360, which was obtained from Amblyomma javanense ticks collected on a pangolin; and (iii) Anaplasma sp. strain AnHl446, which was closely related to Anaplasma bovis and which was detected in Haemaphysalis lagrangei ticks collected from a bear. Three Ehrlichia spp. were identified, including (i) Ehrlichia sp. strain EBm52, which was obtained from Boophilus microplus ticks collected from cattle from Thailand; (ii) Ehrlichia sp. strain EHh324, which was closely related to Ehrlichia chaffeensis and which was detected in Haemaphysalis hystricis ticks collected from wild pigs in Vietnam; and (iii) Ehrlichia sp. strain EHh317, which was closely related to Ehrlichia sp. strain EBm52 and which was also detected in H. hystricis ticks collected from wild pigs in Vietnam. Two Rickettsia spp. were detected in Thailand, including (i) Rickettsia sp. strain RDla420, which was detected in Dermacentor auratus ticks collected from a bear, and (ii) Rickettsia sp. strain RDla440, which was identified from two pools of Dermacentor larvae collected from a wild pig nest. Finally, two bacteria named Eubacterium sp. strain Hw124 and Eubacterium sp. strain Hw191 were identified in Haemaphysalis wellingtoni ticks collected from chicken in Thailand; these strains could belong to a new group of bacteria. PMID:12682151

  7. Detection of Ehrlichia spp., Anaplasma spp., Rickettsia spp., and Other Eubacteria in Ticks from the Thai-Myanmar Border and Vietnam

    PubMed Central

    Parola, Philippe; Cornet, Jean-Paul; Sanogo, Yibayiri Osée; Miller, R. Scott; Thien, Huynh Van; Gonzalez, Jean-Paul; Raoult, Didier; Telford III, Sam R.; Wongsrichanalai, Chansuda

    2003-01-01

    A total of 650 ticks, including 13 species from five genera, were collected from animals, from people, or by flagging of the vegetation at sites on the Thai-Myanmar border and in Vietnam. They were tested by PCR to detect DNA of bacteria of the order Rickettsiales. Three Anaplasma spp. were detected in ticks collected in Thailand, including (i) Anaplasma sp. strain AnDa465, which was considered a genotype of Anaplasma platys (formerly Ehrlichia platys) and which was obtained from Dermacentor auratus ticks collected from dogs; (ii) Anaplasma sp. strain AnAj360, which was obtained from Amblyomma javanense ticks collected on a pangolin; and (iii) Anaplasma sp. strain AnHl446, which was closely related to Anaplasma bovis and which was detected in Haemaphysalis lagrangei ticks collected from a bear. Three Ehrlichia spp. were identified, including (i) Ehrlichia sp. strain EBm52, which was obtained from Boophilus microplus ticks collected from cattle from Thailand; (ii) Ehrlichia sp. strain EHh324, which was closely related to Ehrlichia chaffeensis and which was detected in Haemaphysalis hystricis ticks collected from wild pigs in Vietnam; and (iii) Ehrlichia sp. strain EHh317, which was closely related to Ehrlichia sp. strain EBm52 and which was also detected in H. hystricis ticks collected from wild pigs in Vietnam. Two Rickettsia spp. were detected in Thailand, including (i) Rickettsia sp. strain RDla420, which was detected in Dermacentor auratus ticks collected from a bear, and (ii) Rickettsia sp. strain RDla440, which was identified from two pools of Dermacentor larvae collected from a wild pig nest. Finally, two bacteria named Eubacterium sp. strain Hw124 and Eubacterium sp. strain Hw191 were identified in Haemaphysalis wellingtoni ticks collected from chicken in Thailand; these strains could belong to a new group of bacteria. PMID:12682151

  8. Expanded Geographic Distribution and Clinical Characteristics of Ehrlichia ewingii Infections, United States

    PubMed Central

    Harris, Rebecca M.; Couturier, Brianne A.; Sample, Stephan C.; Coulter, Katrina S.; Casey, Kathleen K.

    2016-01-01

    Ehrlichiosis is a bacterial zoonosis, spread through the bites of infected ticks, that is most commonly caused in the United States by infection with the bacterium Ehrlichia chaffeensis. We retrospectively reviewed samples from an 18-month study of ehrlichiosis in the United States and found that E. ewingii was present in 10 (9.2%) of 109 case-patients with ehrlichiosis, a higher rate of infection with this species than had previously been reported. Two patients resided in New Jersey and Indiana, where cases have not been reported. All patients with available case histories recovered. Our study suggests a higher prevalence and wider geographic distribution of E. ewingii in the United States than previous reports have indicated. PMID:27089171

  9. [Ehrlichia infection in a child: clinical findings and review of the literature].

    PubMed

    Halac, Eduardo

    2016-06-01

    A 12 year old child was brought in by his parents due to persistent fever of 3 weeks duration, sore throat, malaise, chills, small joint arthralgia, myalgias, and a pink macular rash. The first clinical impression of the physicians was infectious mononucleosis but serologic testing ruled out the diagnosis. He was then treated with oral ampicillin without a favorable response. He was referred to us for a second evaluation. A detailed clinical history revealed that he had a few days of vacation in a rural area in the northern region of the province of Cordoba, in close contact with horses, dogs and cats. His parents found 2 ticks on his abdomen, and removed them with tweezers. Serology and blood count carried out in a specialized laboratory showed positive titers (> 160) for Ehrlichia chaffeensis. Further confirmation was obtained using genus-specific polymerase chain reaction. After a 3-week course of doxycicline the patient recovered and serological titers decreased. PMID:27164358

  10. 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

  11. Ehrlichia Meningitis Mimicking Aneurysmal Subarachnoid Hemorrhage: A Case Study for Medical Decision-Making Heuristics.

    PubMed

    Dredla, Brynn; Freeman, William D

    2016-04-01

    Thunderclap headache is a sudden and severe headache that can occur after an aneurysmal subarachnoid hemorrhage (SAH). Subarachnoid hemorrhage is a medical emergency that requires prompt attention and hospitalization. Patients with thunderclap headache often undergo a noncontrast head computed tomography (CT) scan to ascertain SAH bleeding and, if the scan is negative, then undergo a lumbar puncture to look for cerebrospinal fluid (CSF) red blood cells (RBCs), which would be consistent with an aneurysmal leak. If the initial CT is negative and CSF is positive for RBCs, patients are usually admitted to the hospital for evaluation of intracranial aneurysm. We encountered a patient with thunderclap headache whose initial head CT was negative for SAH and whose CSF tested positive for RBCs. The patient was referred to our center for evaluation and management of aneurysmal SAH. However, on careful review of the patient's medical history, serum laboratory values, and spinal fluid values, the patient was diagnosed with Ehrlichia chaffeensis meningitis. While Ehrlichia meningitis is rare, it is important to recognize the clinical clues that could help avoid formal cerebral angiography, a costly and potentially unnecessary procedure. We present how this case represented a cognitive framing bias and anchoring heuristic as well as steps that medical providers can use to prevent such cognitive errors in diagnosis. PMID:27053985

  12. Emerging Tick-borne Rickettsia and Ehrlichia at Joint Base Langley-Eustis, Fort Eustis, Virginia.

    PubMed

    Miller, Melissa K; Jiang, Ju; Truong, Melissa; Yarina, Tamasin; Evans, Holly; Christensen, Timothy P; Richards, Allen L

    2016-01-01

    Four species of ticks known to parasitize humans (Amblyomma americanum (lone star tick), Dermacentor variabilis (American dog tick), Amblyomma maculatum (Gulf Coast tick), and Ixodes scapularis (black-legged tick)) were collected at Joint Base Langley-Eustis, Fort Eustis, Virginia during 2009. These ticks were tested individually (adults and nymphs) and in pools of 15 (larvae) for pathogens of public health importance within the genera: Rickettsia, Borrelia, and Ehrlichia, by quantitative real-time polymerase chain reaction (qPCR) assays and, where appropriate, multilocus sequence typing (MLST). Of the 340 A americanum ticks tested, a minimum of 65 (19%), 4 (1%), 4 (1%), and one (<1%) were positive for Rickettsia amblyommii, B lonestari, E ewingii and E chaffeensis, respectively. One of 2 (50%) A maculatum ticks collected was found to be positive for R parkeri by MLST and qPCR analyses. All 33 D variabilis ticks were negative for evidence of rickettsial infections. Likewise, no pathogenic organisms were detected from the single Ixodes scapularis tick collected. Pathogenic rickettsiae and ehrlichiae are likely emerging and cause under-recognized diseases, which threaten people who live, work, train, or otherwise engage in outdoor activities at, or in the vicinity of, Fort Eustis, Virginia. PMID:27613206

  13. Ehrlichia and Spotted Fever Group Rickettsiae Surveillance in Amblyomma americanum in Virginia Through Use of a Novel Six-Plex Real-Time PCR Assay

    PubMed Central

    Operario, Darwin J.; Stroup, Suzanne; Stromdahl, Ellen; Wright, Chelsea; Gaff, Holly; Broyhill, James; Smith, Joshua; Norris, Douglas E.; Henning, Tyler; Lucas, Agape; Houpt, Eric

    2014-01-01

    Abstract The population of the lone star tick Amblyomma americanum has expanded in North America over the last several decades. It is known to be an aggressive and nondiscriminatory biter and is by far the most common human-biting tick encountered in Virginia. Few studies of human pathogen prevalence in ticks have been conducted in our state since the mid-twentieth century. We developed a six-plex real-time PCR assay to detect three Ehrlichia species (E. chaffeensis, E. ewingii, and Panola Mountain Ehrlichia) and three spotted fever group Rickettsiae (SFGR; R. amblyommii, R. parkeri, and R. rickettsii) and used it to test A. americanum from around the state. Our studies revealed a presence of all three Ehrlichia species (0–24.5%) and a high prevalence (50–80%) of R. amblyommii, a presumptively nonpathogenic SFGR, in all regions surveyed. R. parkeri, previously only detected in Virginia's Amblyomma maculatum ticks, was found in A. americanum in several surveyed areas within two regions having established A. maculatum populations. R. rickettsii was not found in any sample tested. Our study provides the first state-wide screening of A. americanum ticks in recent history and indicates that human exposure to R. amblyommii and to Ehrlichiae may be common. The high prevalence of R. amblyommii, serological cross-reactivity of all SFGR members, and the apparent rarity of R. rickettsii in human biting ticks across the eastern United States suggest that clinical cases of tick-borne disease, including ehrlichiosis, may be commonly misdiagnosed as Rocky Mountain spotted fever, and that suspicion of other SFGR as well as Ehrlichia should be increased. These data may be of relevance to other regions where A. americanum is prevalent. PMID:24746145

  14. Comparison of nested PCR with immunofluorescent-antibody assay for detection of Ehrlichia canis infection in dogs treated with doxycycline.

    PubMed Central

    Wen, B; Rikihisa, Y; Mott, J M; Greene, R; Kim, H Y; Zhi, N; Couto, G C; Unver, A; Bartsch, R

    1997-01-01

    A partial 16S rRNA gene was amplified in Ehrlichia canis-infected cells by nested PCR. The assay was specific and did not amplify the closely related Ehrlichia chaffeensis, Ehrlichia muris, Neorickettsia helminthoeca, and SF agent 16S rRNA genes. The assay was as sensitive as Southern hybridization, detecting as little as 0.2 pg of E. canis DNA. By this method, all blood samples from four dogs experimentally infected with E. canis were positive as early as day 4 postinoculation, which was before or at the time of seroconversion. One hundred five blood samples from dogs from Arizona and Texas (areas of E. canis endemicity) and 30 blood samples from dogs from Ohio (area of E. canis nonendemicity) were examined by nested PCR and immunofluorescent-antibody (IFA) test. Approximately 84% of dogs from Arizona and Texas had been treated with doxycycline before submission of blood specimens. Among Arizona and Texas specimens, 46 samples were PCR positive (44%) and 80 were IFA positive (76%). Forty-three of 80 IFA-positive samples (54%) were PCR positive, and 22 of 25 IFA-negative samples (88%) were negative in the nested PCR. None of the Ohio specimens were IFA positive, but 5 specimens were PCR positive (17%). Our results indicate that the nested PCR is highly sensitive and specific for detection of E. canis and may be more useful in assessing the clearance of the organisms after antibiotic therapy than IFA, especially in areas in which E. canis is endemic. PMID:9196207

  15. Natural history of Ehrlichia ruminantium.

    PubMed

    Allsopp, Basil A

    2010-02-10

    Ehrlichia ruminantium is an obligately intracellular proteobacterium which causes a disease known as heartwater or cowdriosis in some wild, and all domestic, ruminants. The organism is transmitted by ticks of the genus Amblyomma, and it is of serious economic importance wherever the natural vectors occur, an area which includes all of sub-Saharan Africa, and several islands in the Caribbean. The disease was first recognized in South Africa in the 19th century, where its tick-borne nature was determined in 1900, but the organism itself was not demonstrated until 1925, when it was recognized to be a rickettsia, initially named Rickettsia ruminantium. It was thus the first species of what are now known as Ehrlichia to be discovered, and most of the early work to elucidate the nature of the organisms, and its reservoirs and vectors, was performed in South Africa. The next milestone was the development, in 1945, of an infection and treatment regimen to immunize livestock, and this is still the only commercially available "vaccine" against the disease. Then in 1985, after fruitless attempts over many years, the organism was propagated reliably in tissue culture, opening the way for the first application of the newly developed techniques of molecular genetics. From 1990 onwards the pace of heartwater research accelerated rapidly, with notable advances in phylogeny, diagnosis, epidemiology, immunology, and vaccine development. The complete genome sequence was published in 2005, and during the last two years a new understanding has arisen of the remarkable genetic variability of the organism and new experimental vaccines have been developed. Despite all this the goal of producing an effective vaccine against the disease in the field still remains frustratingly just beyond reach. This article summarises our current understanding of the nature of E. ruminantium, at a time when the prospects for the development of an effective vaccine against the organism seem better than at

  16. Hemocytic rickettsia-like organisms in ticks: serologic reactivity with antisera to Ehrlichiae and detection of DNA of agent of human granulocytic ehrlichiosis by PCR.

    PubMed

    Magnarelli, L A; Stafford, K C; Mather, T N; Yeh, M T; Horn, K D; Dumler, J S

    1995-10-01

    Ixodid ticks were collected from Connecticut, Massachusetts, Missouri, Pennsylvania, Rhode Island, and British Columbia (Canada) during 1991 to 1994 to determine the prevalence of infection with hemocytic (blood cell), rickettsia-like organisms. Hemolymph obtained from these ticks was analyzed by direct and indirect fluorescent antibody (FA) staining methods with dog, horse, or human sera containing antibodies to Ehrlichia canis, Ehrlichia equi, or Rickettsia rickettsii. Of the 693 nymphal and adult Amblyomma americanum, Dermacentor variabilis, Ixodes scapularis, and Ixodes pacificus ticks tested with dog anti-E. canis antiserum, 209 (32.5%) contained hemocytic bacteria. The prevalence of infected ticks varied greatly with species and locale. In parallel tests of duplicate hemolymph preparations from adult I. scapularis ticks, the hemocytic organisms reacted positively with E. canis and/or E. equi antisera, including sera from persons who had granulocytic ehrlichiosis. In separate PCR analyses, DNA of the agent of human granulocytic ehrlichiosis was detected in 59 (50.0%) of 118 adult and in 1 of 2 nymphal I. scapularis ticks tested from Connecticut. There was no evidence of Ehrlichia chaffeensis DNA in these ticks. In indirect FA tests of hemolymph for spotted fever group rickettsiae, the overall prevalence of infection was less than 4%. Specificity tests of antigens and antisera used in these studies revealed no cross-reactivity between E. canis and E. equi or between any of the ehrlichial reagents and those of R. rickettsii. The geographic distribution of hemocytic microorganisms with shared antigens to Ehrlichia species or spotted fever group rickettsiae is widespread. PMID:8567911

  17. Introduction to the alpha-proteobacteria: Wolbachia and Bartonella, Rickettsia, Brucella, Ehrlichia, and Anaplasma.

    PubMed

    Bowman, Dwight D

    2011-11-01

    Wolbachia is an obligate intracellular endosymbiont and likely mutualist living within the heartworm Dirofilaria immitis and a number of other filarial nematodes in the family Onchocercidae. The bacterial infection is passed from worm to worm transovarially; the organisms are in ovarian cells, the developing microfilariae, and multiply and persist in all later developmental stages through the mosquito and into the next host. Besides being present in the ovaries of the adult worms, they also are present in large numbers within the hypodermal tissues of the nematode. It is now know that these bacteria that were first observed in heartworms more than 30 years ago are actually related to similar Wolbachia bacteria that are found in arthropods. Wolbachia is an alpha-proteobacteria, and this group includes a number of important arthropod-transmitted bacterial agents of dogs and cats: Rickettsia rickettsii, R. felis, Anaplasma platys, Ehrlichia canis, E. chaffeensis, and E. ewingii. Alpha-proteobacteria are also important as obligate intracellular mutualists in plants in which they are responsible for nitrogen fixation. Recent work on the treatment of heartworms in dogs with doxycycline stems from related work with the human filarial nematode Onchocerca volvulus that causes river blindness in people. PMID:22152604

  18. Complete Genome Sequence of Ehrlichia mineirensis, a Novel Organism Closely Related to Ehrlichia canis with a New Host Association

    PubMed Central

    Cabezas-Cruz, Alejandro; Zweygarth, Erich; Broniszweska, Marzena; Passos, Lygia M. F.; Ribeiro, Múcio Flávio Barbosa; Manrique, Marina; Tobes, Raquel

    2015-01-01

    We report here the complete genome sequencing of Ehrlichia mineirensis, an Ehrlichia organism that was isolated from the hemolymph of Rhipicephalus microplus–engorged females. E. mineirensis is the best characterized Ehrlichia isolate from a novel cattle-related clade closely related to the monocytotropic pathogen E. canis. PMID:25614563

  19. Heartwater--Ehrlichia ruminantium infection.

    PubMed

    Allsopp, B A

    2015-08-01

    Summary Heartwater is a notifiable disease that is listed by the World Organisation for Animal Health. It is caused by Ehrlichia ruminantium, an obligately intracellular Gram-negative bacterium in the order Rickettsiales and the family Anaplasmataceae. The disease is borne byticks in the genus Amblyomma and causes heartwater, or cowdriosis, in wild and domestic ruminants, primarily in Africa, but also in parts of the Caribbean. The disease was recognised in South Africa in the 19th Century and determined to be tick borne in 1900, while the organism was identified in 1925 and first cultured in vitro in 1985. This latter achievement boosted research into the disease at a time when biology was moving into the molecular genetic age. Over the last 20 years, there have been significant improvements in our understanding of E. ruminantium, yielding major advances in diagnosis, epidemiology, genetic characterisation, phylogeny, immunology, and vaccine development. The organism is genetically highly variable; this has important implications for future control measures, and is making it difficult to develop an effective vaccine for protection against tick challenge. Research is continuing into three different types of vaccine, inactivated, attenuated, and recombinant, and the current state of development of each is discussed. PMID:26601456

  20. A novel Ehrlichia genotype strain distinguished by the TRP36 gene naturally infects cattle in Brazil and causes clinical manifestations associated with ehrlichiosis.

    PubMed

    Aguiar, Daniel M; Ziliani, Thayza F; Zhang, Xiaofeng; Melo, Andreia L T; Braga, Isis A; Witter, Rute; Freitas, Leodil C; Rondelli, André L H; Luis, Michele A; Sorte, Eveline C B; Jaune, Felipe W; Santarém, Vamilton A; Horta, Mauricio C; Pescador, Carolina A; Colodel, Edson M; Soares, Herbert S; Pacheco, Richard C; Onuma, Selma S M; Labruna, Marcelo B; McBride, Jere W

    2014-09-01

    A novel Ehrlichia genotype most closely related to E. canis was reported in North American cattle in 2010, and a similar agent was subsequently identified in the hemolymph of Brazilian Rhipicephalus (Boophilus) microplus ticks and isolated in 2012. The purpose of this study was to determine whether this or other novel ehrlichial agents naturally infect Brazilian cattle. Using PCR targeting the genus-conserved dsb gene, DNA from this novel ehrlichial agent in Brazilian cattle was detected. Attempts to isolate the organism in vitro were performed using DH82 cells, but morulae and ehrlichial DNA could only be detected for approximately one month. In order to further molecularly characterize the organism, PCR was performed using primers specific for multiple E. canis genes (dsb, rrs, and trp36). Sequence obtained from the conserved rrs and dsb genes demonstrated that the organism was 99-100% identical to the novel Ehrlichia genotypes previously reported in North American cattle (rrs gene) and Brazilian ticks (rrs and dsb genes). However, analysis of the trp36 gene revealed substantial strain diversity between these Ehrlichia genotypes strains, including divergent tandem repeat sequences. In order to obtain preliminary information on the potential pathogenicity of this ehrlichial agent and clinical course of infection, a calf was experimentally infected. The calf showed clinical signs of ehrlichiosis, including fever, depression, lethargy, thrombocytopenia, and morulae were observed in peripheral blood monocytes. This study reports a previously unrecognized disease-causing Ehrlichia sp. in Brazilian cattle that is consistent with the genotype previously described in North America cattle and ticks from Brazil. Hence, it is likely that this is the organism previously identified as Ehrlichia bovis in Brazil in 1982. Furthermore, we have concluded that strains of these Ehrlichia genotypes can be molecularly distinguished by the trp36 gene, which has been widely utilized to

  1. TpE: PANOLA MOUNTAIN EHRLICHIA: A NOVEL TICK-TRANSMITTED PATHOGEN IN THE USA CLOSELY RELATED TO EHRLICHIA RUMINANTIUM, CAUSAL AGENT OF HEARTWATER DISEASE IN RUMINANTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ehrlichia ruminantium, the economically most important pathogen in the genus Ehrlichia, is enzootic in sub-Saharan Africa and occurs on islands in the Caribbean. The pathogen causes heartwater disease in ruminants and might also cause illness in humans. We recently found a novel Ehrlichia, genetical...

  2. Retrospective Clinical and Molecular Analysis of Conditioned Laboratory Dogs (Canis familiaris) with Serologic Reactions to Ehrlichia canis, Borrelia burgdorferi, and Rickettsia rickettsii

    PubMed Central

    Scorpio, Diana G; Wachtman, Lynn M; Tunin, Richard S; Barat, Nicole C; Garyu, Justin W; Dumler, J Stephen

    2008-01-01

    Dogs are susceptible to different tickborne infections, including members of the Anaplasmataceae (Ehrlichia canis, E. ewingii, E. chaffeensis, Anaplasma phagocytophilum, A. platys), Borrelia burgdorferi, and Rickettsia rickettsii. These diseases can manifest with clinical signs including fever, anorexia, malaise, lameness, rash, and bleeding episodes; however, these signs are nonpathognomonic, and infections can occur in the absence of clinical signs. Hematologic abnormalities can include leukopenia, thrombocytopenia, hyperproteinemia and hypergammaglobulinemia. In biomedical research, diseases such as canine monocytic ehrlichiosis, Lyme disease, and Rocky Mountain spotted fever may cause morbidity among exposed dogs and confound research results. Random-source dogs are susceptible to these diseases because of their increased risk of arthropod exposure. Nonpurpose bred, randomly selected conditioned dogs (n = 21) were examined; blood samples were taken for hematology, biochemistry analysis, tickborne pathogen serology, and PCR. Of these, 2 dogs (10% of the population) presented with illness characterized by fever, malaise, lameness, or hemostatic abnormalities, and 15 (71%) had antibodies to one or more tickborne pathogens. No specific hematologic or biochemical differences were apparent between seronegative dogs and seropositive dogs reactive to all 3 pathogens. E. canis and B. burgdorferi PCR of tissues and blood were negative for all dogs. PCR amplification of several Ehrlichia and Anaplasma genes yielded no positive samples. From this cohort of dogs, serologic and molecular results indicate prior exposure without active infection or clinical disease. Exposure to and potential for infection with these bacteria and other pathogens may contribute to blood and tissue alterations that could confound experiments and lead to misinterpretation of data in canine models. PMID:18947166

  3. Retrospective clinical and molecular analysis of conditioned laboratory dogs (Canis familiaris) with serologic reactions to Ehrlichia canis, Borrelia burgdorferi, and Rickettsia rickettsii.

    PubMed

    Scorpio, Diana G; Wachtman, Lynn M; Tunin, Richard S; Barat, Nicole C; Garyu, Justin W; Dumler, J Stephen

    2008-09-01

    Dogs are susceptible to different tickborne infections, including members of the Anaplasmataceae (Ehrlichia canis, E. ewingii, E. chaffeensis, Anaplasma phagocytophilum, A. platys), Borrelia burgdorferi, and Rickettsia rickettsii. These diseases can manifest with clinical signs including fever, anorexia, malaise, lameness, rash, and bleeding episodes; however, these signs are nonpathognomonic, and infections can occur in the absence of clinical signs. Hematologic abnormalities can include leukopenia, thrombocytopenia, hyperproteinemia and hypergammaglobulinemia. In biomedical research, diseases such as canine monocytic ehrlichiosis, Lyme disease, and Rocky Mountain spotted fever may cause morbidity among exposed dogs and confound research results. Random-source dogs are susceptible to these diseases because of their increased risk of arthropod exposure. Nonpurpose bred, randomly selected conditioned dogs (n = 21) were examined; blood samples were taken for hematology, biochemistry analysis, tickborne pathogen serology, and PCR. Of these, 2 dogs (10% of the population) presented with illness characterized by fever, malaise, lameness, or hemostatic abnormalities, and 15 (71%) had antibodies to one or more tickborne pathogens. No specific hematologic or biochemical differences were apparent between seronegative dogs and seropositive dogs reactive to all 3 pathogens. E. canis and B. burgdorferi PCR of tissues and blood were negative for all dogs. PCR amplification of several Ehrlichia and Anaplasma genes yielded no positive samples. From this cohort of dogs, serologic and molecular results indicate prior exposure without active infection or clinical disease. Exposure to and potential for infection with these bacteria and other pathogens may contribute to blood and tissue alterations that could confound experiments and lead to misinterpretation of data in canine models. PMID:18947166

  4. Detection of a Novel Ehrlichia Species in Haemaphysalis longicornis Tick from China.

    PubMed

    Luo, Limei; Sun, Jimin; Yan, Jianbo; Wang, Chengwei; Zhang, Zhentang; Zhao, Li; Han, Huiju; Tong, Zhendong; Liu, Miaomiao; Wu, Yuyan; Wen, Hongling; Zhang, Rong; Xue, Zaifeng; Sun, Xifeng; Li, Kefeng; Ma, Dongqiang; Liu, Jianwei; Huang, Yuting; Ye, Ling; Li, Wenqian; Jiang, Jianmin; Yu, Xue-Jie

    2016-06-01

    We collected 2460 Haemaphysalis longicornis ticks from vegetation in Jiaonan County, Shandong Province, in June of 2013 and Daishan County, Zhejiang Province, China, in May of 2015. The tick DNA was subsequently amplified with nested polymerase chain reaction using Ehrlichia common 16S rRNA gene primers and Ehrlichia ewingii species-specific groEL and gltA primers. We found 0.4% (3/780) of the ticks from Zhejiang Province contained Ehrlichia DNA that was different from all known Ehrlichia species, but most closely related to E. ewingii. We concluded that a novel Ehrlichia species exists in H. longicornis ticks in China. PMID:27135624

  5. Ehrlichia's molecular tricks to manipulate their host cells.

    PubMed

    Moumène, Amal; Meyer, Damien F

    2016-03-01

    Ehrlichia is a large genus of obligate intracellular Gram-negative bacteria transmitted by ticks that cause several emerging infectious diseases in humans and are pathogenic on rodents, ruminants, and dogs. Ehrlichia spp. invade and replicate either in endothelial cells, white blood cells, or within midgut cells and salivary glands of their vector ticks. In this review, we discuss the insights that functional studies are providing on how this group of bacteria exploits their host by subverting host innate immunity and hijacking cellular processes. PMID:26617397

  6. [Factors associated with Ehrlichia canis infection in dogs infested with ticks from Huanuco, Peru].

    PubMed

    Huerto-Medina, Edward; Dámaso-Mata, Bernardo

    2015-10-01

    The aim of the study was to determine the frequency and associated factors of Ehrlichia canis infection in dogs. Blood samples from 150 dogs infested with ticks in 10 veterinary clinics in the city of Huanuco in Peru were collected. The dogs were randomly selected without regard to breed, age or sex. Ehrlichia canis antibodies were detected by chromatographic immunoassay.51.3% of dogs were infected with Ehrlichia canis. In the multivariate analysis, factors associated with the presence of Ehrlichia canis were: poor health of the dog (p = 0.049), a higher average of tick infestation (p = 0.018), and adult dogs (p = 0.038). The frequency of Ehrlichia canis in dogs of this city is high. Control of the brown dog tick (Rhipicephalus sanguineus) vector of Ehrlichia canis is recommended. PMID:26732926

  7. The genome of obligately intracellular Ehrlichia canis revealsthemes of complex membrane structure and immune evasion strategies

    SciTech Connect

    Mavromatis, K.; Kuyler Doyle, C.; Lykidis, A.; Ivanova, N.; Francino, P.; Chain, P.; Shin, M.; Malfatti, S.; Larimer, F.; Copeland,A.; Detter, J.C.; Land, M.; Richardson, P.M.; Yu, X.J.; Walker, D.H.; McBride, J.W.; Kyrpides, N.C.

    2005-09-01

    Ehrlichia canis, a small obligately intracellular, tick-transmitted, gram-negative, a-proteobacterium is the primary etiologic agent of globally distributed canine monocytic ehrlichiosis. Complete genome sequencing revealed that the E. canis genome consists of a single circular chromosome of 1,315,030 bp predicted to encode 925 proteins, 40 stable RNA species, and 17 putative pseudogenes, and a substantial proportion of non-coding sequence (27 percent). Interesting genome features include a large set of proteins with transmembrane helices and/or signal sequences, and a unique serine-threonine bias associated with the potential for O-glycosylation that was prominent in proteins associated with pathogen-host interactions. Furthermore, two paralogous protein families associated with immune evasion were identified, one of which contains poly G:C tracts, suggesting that they may play a role in phase variation and facilitation of persistent infections. Proteins associated with pathogen-host interactions were identified including a small group of proteins (12) with tandem repeats and another with eukaryotic-like ankyrin domains (7).

  8. Molecular Detection of Ehrlichia canis in Dogs in Malaysia

    PubMed Central

    Nazari, Mojgan; Lim, Sue Yee; Watanabe, Mahira; Sharma, Reuben S. K.; Cheng, Nadzariah A. B. Y.; Watanabe, Malaika

    2013-01-01

    An epidemiological study of Ehrlichia canis infection in dogs in Peninsular Malaysia was carried out using molecular detection techniques. A total of 500 canine blood samples were collected from veterinary clinics and dog shelters. Molecular screening by polymerase chain reaction (PCR) was performed using genus-specific primers followed by PCR using E. canis species-specific primers. Ten out of 500 dogs were positive for E. canis. A phylogenetic analysis of the E. canis Malaysia strain showed that it was grouped tightly with other E. canis strains from different geographic regions. The present study revealed for the first time, the presence of genetically confirmed E. canis with a prevalence rate of 2.0% in naturally infected dogs in Malaysia. PMID:23301114

  9. The Genome of the Obligately Intracellular Bacterium Ehrlichia canis Reveals Themes of Complex Membrane Structure and Immune Evasion Strategies

    SciTech Connect

    Mavromatis, K; Doyle, C Kuyler; Lykidis, A; Ivanova, N; Francino, M P; Chain, Patrick S; Shin, M; Malfatti, Stephanie; Larimer, Frank W; Copeland, A; Detter, J C; Land, Miriam L; Richardson, P M; Yu, X J; Walker, D H; McBride, J W; Kyripides, N C

    2006-01-01

    Ehrlichia canis, a small obligately intracellular, tick-transmitted, gram-negative, {alpha}-proteobacterium, is the primary etiologic agent of globally distributed canine monocytic ehrlichiosis. Complete genome sequencing revealed that the E. canis genome consists of a single circular chromosome of 1,315,030 bp predicted to encode 925 proteins, 40 stable RNA species, 17 putative pseudogenes, and a substantial proportion of noncoding sequence (27%). Interesting genome features include a large set of proteins with transmembrane helices and/or signal sequences and a unique serine-threonine bias associated with the potential for O glycosylation that was prominent in proteins associated with pathogen-host interactions. Furthermore, two paralogous protein families associated with immune evasion were identified, one of which contains poly(G-C) tracts, suggesting that they may play a role in phase variation and facilitation of persistent infections. Genes associated with pathogen-host interactions were identified, including a small group encoding proteins (n = 12) with tandem repeats and another group encoding proteins with eukaryote-like ankyrin domains (n = 7).

  10. Occurrence of Ehrlichia canis in free-living primates of the genus Callithrix.

    PubMed

    Mafra, Claudio; Barcelos, Rafael Mazioli; Mantovani, Cynthia; Carrizo, Juliana; Soares, Adriano Carlos; Moreira, Higo Nasser Sant'Anna; Maia, Natasha Lagos; da Silva, Fernanda de Fátima Rodrigues; e Silva, Vinícius Herold Dornelas; Boere, Vanner; e Silva, Ita de Oliveira

    2015-01-01

    Bacteria of the genus Ehrlichia are Gram-negative and coccoid-shaped microorganisms that cause ehrlichiosis - a serious infectious disease that often leads to death. These bacteria present a strong zoonotic potential and primates may act as reservoir hosts. This study involved a molecular analysis to detect these microorganisms in blood samples collected from nineteen primates of the genus Callithrix living free in an Atlantic Forest fragment in the municipality of Viçosa, state of Minas Gerais, Brazil. One of the 19 primates was found to be infected with Ehrlichia canis. This finding points to a new wild host of E. canis with a strong potential for transmission to humans because of its increasing contact with people. This is the first report of Ehrlichia spp. in primate of the genus Callithrix. PMID:25909257

  11. A molecular epidemiological survey of Babesia, Hepatozoon, Ehrlichia and Anaplasma infections of dogs in Japan.

    PubMed

    Kubo, Shotaro; Tateno, Morihiro; Ichikawa, Yasuaki; Endo, Yasuyuki

    2015-10-01

    Tick-borne diseases are often encountered in canine clinical practice. In the present study, a molecular epidemiological survey of dogs in Japan was conducted to understand the prevalence and geographical distribution of Babesia spp., Hepatozoon spp., Ehrlichia spp. and Anaplasma spp. Pathogen-derived DNA in blood samples obtained from 722 dogs with a history of exposure to ticks and/or fleas was examined by PCR. The prevalence of Babesia gibsoni, Babesia odocoilei-like species, Hepatozoon canis and Ehrlichia spp./Anaplasma spp. was 2.4% (16/722), 0.1% (1/722), 2.5% (18/722) and 1.5% (11/722), respectively. While B. gibsoni and Ehrlichia spp./Anaplasma spp. were detected in the western part of Japan, H. canis was detected in Tohoku area in addition to western and central parts of Japan. PMID:25947226

  12. Serodetection of Ehrlichia canis amongst dogs in central Namibia.

    PubMed

    Manyarara, Rutendo; Tubbesing, Ulf; Soni, Minty; Noden, Bruce H

    2015-01-01

    Ehrlichia canis is a major pathogen in dogs throughout Africa, yet it has not been reported in Namibia. The aim of this study was to determine the seroprevalence of canine ehrlichiosis in central Namibia using the ImmunoComb assay (Biogal, Galed Laboratories). The study included 76 dogs that presented to the Rhino Park Veterinary Clinic in the north-western suburb of Khomasdal, Windhoek, Namibia, as well as 30 stray dogs from the Windhoek branch of the Society for the Prevention of Cruelty to Animals. Of the 106 dogs tested, 53.8% were seropositive at titres > 1:80. Dogs that presented with symptoms of E. canis infection had a significantly higher seroprevalence (86.6%) compared with apparently healthy dogs (41.6%) (P = 0.00). Location of habitation was significant (P < 0.017), with a high percentage of dogs exposed to E. canis living in the northern or north-western part of Windhoek. As the first study to serologically establish E. canis as a major pathogen in dogs in central Namibia, it is notable that the highest proportion of seropositive dogs came from low-income areas. Further investigation is necessary to describe the ecology of this important tick-borne pathogen of companion animals in Namibia. PMID:26244587

  13. Molecular characterization of Ehrlichia canis infecting dogs, Buenos Aires.

    PubMed

    Cicuttin, Gabriel L; De Salvo, María N; Gury Dohmen, Federico E

    2016-07-01

    Canine monocytic ehrlichiosis (CME) is a worldwide potentially fatal tick-borne rickettsial disease of dogs caused by Ehrlichia canis and transmitted by Rhipicephalus sanguineus sensu lato. CME diagnosis includes indirect (serology) and direct (e.g. blood smears and PCR) methods. PCR is more sensitive and specific than direct microscopic examination and positive PCR results confirm infection, whereas positive serologic test results only confirm exposure. The aim of the present study was to perform a molecular characterization of E. canis from canine samples of the Metropolitan Area of Buenos Aires. We studied 223 blood samples of dogs submitted to our institute for CME diagnoses. The samples were initially screened for Anaplasmataceae family by PCR, resulting in 30 positive dogs (13.4%). Subsequently, positive DNAs were analyzed by nested PCR 16S rRNA specific for E. canis or Anaplasma platys, resulting in 15 (6.7%) and 16 (7.2%) positive dogs, respectively. For molecular characterization, samples positive for E. canis were subjected to amplification of a fragment of the dsb and p28 genes. The nucleotide sequences obtained for the dsb fragment resulted in 100% identity with others E. canis found in dogs from different regions of worldwide. The nucleotide sequences obtained for p28 gene resulted in 100% of identity with each other and closely with E. canis str. Jaboticabal (Brazil). Identity with others sequences of E. canis ranged from 76.9 to 79.7%. The occurrence of canine cases molecularly confirmed in Metropolitan Area of Buenos Aires highlights the need for more studies in order to understand epidemiological factors associated with CME, especially the disease transmission dynamic in South America given the existence of two lineages of R. sanguineus sensu lato with different vectorial capacity for transmission of E. canis. PMID:27236582

  14. Molecular and Cellular Pathobiology of Ehrlichia Infection: Targets for New Therapeutics and Immunomodulation Strategies

    PubMed Central

    McBride, Jere W.; Walker, David H.

    2013-01-01

    Ehrlichia are small gram-negative obligately intracellular bacteria in the order Rickettsiales that are transmitted by ticks and associated with emerging life-threatening human zoonoses. Vaccines are not available for human ehrlichiosis, and therapeutic options are limited to a single antibiotic class. Ehrlichia are able to subvert both innate and adaptive host defenses, and advances in understanding molecular Ehrlichia-eukaryotic host cell interactions and the cellular and immunologic basis of disease are important for developing effective next generation therapies. New technologies for exploring host-pathogen interactions have yielded recent advances in understanding the molecular interactions between these intracellular pathogens and host cell components and identified new targets for therapeutic and vaccine development including those that target pathogen virulence mechanisms or disrupt the processes associated with ehrlichial effector proteins. Animal models have also provided insight into immunopathologic mechanisms that contribute significantly to understanding severe disease manifestations that will lead to the development of immunomodulatory approaches for treating patients nearing or experiencing severe disease states. In this review, we discuss the recent advances in our understanding of molecular and cellular pathobiology and the immunobiology of Ehrlichia infection. We identify new molecular host-pathogen interactions that can be targets of new therapeutics and prospects for treating immunologic dysregulation that occurs during acute infection leading to life-threatening complications. PMID:21276277

  15. The Microbiome of Ehrlichia-Infected and Uninfected Lone Star Ticks (Amblyomma americanum).

    PubMed

    Trout Fryxell, R T; DeBruyn, J M

    2016-01-01

    The Lone Star tick, Amblyomma americanum, transmits several bacterial pathogens including species of Anaplasma and Ehrlichia. Amblyomma americanum also hosts a number of non-pathogenic bacterial endosymbionts. Recent studies of other arthropod and insect vectors have documented that commensal microflora can influence transmission of vector-borne pathogens; however, little is known about tick microbiomes and their possible influence on tick-borne diseases. Our objective was to compare bacterial communities associated with A. americanum, comparing Anaplasma/Ehrlichia -infected and uninfected ticks. Field-collected questing specimens (n = 50) were used in the analyses, of which 17 were identified as Anaplasma/Ehrlichia infected based on PCR amplification and sequencing of groEL genes. Bacterial communities from each specimen were characterized using Illumina sequencing of 16S rRNA gene amplicon libraries. There was a broad range in diversity between samples, with inverse Simpson's Diversity indices ranging from 1.28-89.5. There were no statistical differences in the overall microbial community structure between PCR diagnosed Anaplasma/Ehrlichia-positive and negative ticks, but there were differences based on collection method (P < 0.05), collection site (P < 0.05), and sex (P < 0.1) suggesting that environmental factors may structure A. americanum microbiomes. Interestingly, there was not always agreement between Illumina sequencing and PCR diagnostics: Ehrlichia was identified in 16S rRNA gene libraries from three PCR-negative specimens; conversely, Ehrlichia was not found in libraries of six PCR-positive ticks. Illumina sequencing also helped identify co-infections, for example, one specimen had both Ehrlichia and Anaplasma. Other taxa of interest in these specimens included Coxiella, Borrelia, and Rickettsia. Identification of bacterial community differences between specimens of a single tick species from a single geographical site indicates that intra

  16. The Microbiome of Ehrlichia-Infected and Uninfected Lone Star Ticks (Amblyomma americanum)

    PubMed Central

    Trout Fryxell, R. T.; DeBruyn, J. M.

    2016-01-01

    The Lone Star tick, Amblyomma americanum, transmits several bacterial pathogens including species of Anaplasma and Ehrlichia. Amblyomma americanum also hosts a number of non-pathogenic bacterial endosymbionts. Recent studies of other arthropod and insect vectors have documented that commensal microflora can influence transmission of vector-borne pathogens; however, little is known about tick microbiomes and their possible influence on tick-borne diseases. Our objective was to compare bacterial communities associated with A. americanum, comparing Anaplasma/Ehrlichia -infected and uninfected ticks. Field-collected questing specimens (n = 50) were used in the analyses, of which 17 were identified as Anaplasma/Ehrlichia infected based on PCR amplification and sequencing of groEL genes. Bacterial communities from each specimen were characterized using Illumina sequencing of 16S rRNA gene amplicon libraries. There was a broad range in diversity between samples, with inverse Simpson’s Diversity indices ranging from 1.28–89.5. There were no statistical differences in the overall microbial community structure between PCR diagnosed Anaplasma/Ehrlichia-positive and negative ticks, but there were differences based on collection method (P < 0.05), collection site (P < 0.05), and sex (P < 0.1) suggesting that environmental factors may structure A. americanum microbiomes. Interestingly, there was not always agreement between Illumina sequencing and PCR diagnostics: Ehrlichia was identified in 16S rRNA gene libraries from three PCR-negative specimens; conversely, Ehrlichia was not found in libraries of six PCR-positive ticks. Illumina sequencing also helped identify co-infections, for example, one specimen had both Ehrlichia and Anaplasma. Other taxa of interest in these specimens included Coxiella, Borrelia, and Rickettsia. Identification of bacterial community differences between specimens of a single tick species from a single geographical site indicates that intra

  17. Prevalence of granulocytic Ehrlichia infection among white-tailed deer in Wisconsin.

    PubMed Central

    Belongia, E A; Reed, K D; Mitchell, P D; Kolbert, C P; Persing, D H; Gill, J S; Kazmierczak, J J

    1997-01-01

    Human granulocytic ehrlichiosis (HGE) is caused by an agent that is nearly indistinguishable from the veterinary pathogens Ehrlichia equi and Ehrlichia phagocytophila. The deer tick, Ixodes scapularis, is a vector of the HGE agent, and the white-tailed deer is the primary host for adult Ixodes ticks. We assessed the distribution of granulocytic Ehrlichia infection among deer living within (Wisconsin) and outside (western and southern Iowa) the geographic range of L. scapularis. Whole-blood samples were tested for HGE 16S ribosomal DNA (rDNA) by PCR, and E. equi antibody was detected by indirect immunofluorescence assay (IFA). Antibody titers of > or = 1:64 were defined as positive, and all positive samples were retested with a second lot of substrate antigen. E. equi antibody was present in 14 (8%) of 187 Wisconsin deer and 0 of 60 Iowa specimens (rate ratio undefined; P = 0.025). An additional 30 serum samples from Wisconsin deer were excluded because IFA results were discrepant between substrate lots. The reciprocal antibody titers ranged from 64 to 512 (geometric mean, 141) for positive samples. PCR results were positive for 27 (15%) of 181 Wisconsin deer. The prevalence of infection in northwestern Wisconsin deer was not significantly different from that in central Wisconsin deer, as determined by IFA and PCR. In two samples that were sequenced, the 16S rDNA was nearly identical to that of the granulocytic Ehrlichia species but distinct from that of Anaplasma marginale. The DNA sequences of the samples differed from the published sequences for E. equi, E. phagocytophila, and the HGE agent by 1 or 2 nucleotides (> or = 99.1% homology) at phylogenetically informative sites. Granulocytic Ehrlichia organisms in deer are widely distributed within the geographic range of L. scapularis in Wisconsin. Deer may serve as useful sentinels for areas where HGE transmission to humans may occur. PMID:9163463

  18. Minimum infection rate of Ehrlichia minasensis in Rhipicephalus microplus and Amblyomma sculptum ticks in Brazil.

    PubMed

    Carvalho, Izabelle T S; Melo, Andréia L T; Freitas, Leodil C; Verçoza, Rodolfo V; Alves, Alvair S; Costa, Jackeliny S; Chitarra, Cristiane S; Nakazato, Luciano; Dutra, Valéria; Pacheco, Richard C; Aguiar, Daniel M

    2016-07-01

    A new genotype phylogenetically close to Ehrlichia canis named as Ehrlichia minasensis was identified infecting cattle and deer in Canada, as well as Rhipicephalus microplus ticks and cattle in Brazil. Although it was detected in R. microplus, little is known about the epidemiology of this ehrlichiosis, especially in other tick species. This study evaluated the minimum infection rate of E. minasensis in Amblyomma sculptum and R. microplus ticks from locations where naturally infected cattle were previously detected. Overall, 45 engorged R. microplus ticks after molting [43 pools of adults (13.4%), and 2 pools of nymphs (4%)], and 42 engorged females post-oviposition (30.6%) (p=0.008) were positive by PCR for Ehrlichia sp. using the dsb, 16S rRNA and TRP36 genes, making a total of 87 R. microplus samples positive for Ehrlichia spp. (17.1%, IC 95% 14.01-20.75%). The partial sequences generated in the present study were 99-100% similar to the dsb DNA sequence of E. minasensis genotypes UFMG-EV and UFMT-BV, respectively, 100% similar to the 16S rRNA sequence of the E. minasensis genotype BOV2010 from Canada, and 99% similar to the TRP36 sequence of the Ehrlichia sp. UFMT-BV. The results of this study confirm the occurrence of transstadial transmission of this agent in R. microplus ticks and highlight the importance of R. microplus in the epidemiology and transmission of ehrlichiosis in cattle. No A. sculptum ticks were positive by PCR for E. minasensis. PMID:27084673

  19. Characterization of Ehrlichia risticii binding, internalization, and proliferation in host cells by flow cytometry.

    PubMed Central

    Messick, J B; Rikihisa, Y

    1993-01-01

    The binding, internalization, and proliferation of Ehrlichia risticii in P388D1 cells and equine polymorphonuclear (PMN) leukocytes were studied by immunofluorescent staining and flow cytometric analysis. The binding of ehrlichiae to P388D1 cells at 4 degrees C was dose dependent, and the antigens of bound organisms were susceptible to pronase treatment. Additionally, the binding of ehrlichiae to P388D1 cells was diminished when either P388D1 cells or ehrlichiae were treated with 1% paraformaldehyde for 30 min or 0.25% trypsin for 15 min. These results indicate that the ehrlichial ligand and host cell receptor are likely surface proteins. Following incubation at 37 degrees C, bound E. risticii and/or its antigens were removed with pronase and indirect immunofluorescent staining in the presence of saponin was used to examine intracellular ehrlichiae. Our results indicate that E. risticii was internalized into P388D1 cells within 3 h and proliferated by 48 h of incubation. The microfilament-disrupting agent cytochalasin D and the transglutaminase inhibitor monodansylcadaverine were used to differentiate between phagocytosis (sensitive to cytochalasin) and receptor-mediated endocytosis (sensitive to monodansylcadaverine) of E. risticii by P388D1 cells. In concentrations that produced distinctive morphological changes and inhibited phagocytosis of polystyrene latex beads, cytochalasin D did not suppress the infectivity of E. risticii. Binding, internalization, or proliferation of E. risticii was not affected by cytochalasin D. However, monodansylcadaverine inhibited infection of E. risticii in a dose-dependent manner. The agent did not affect the attachment of ehrlichiae to host cells, but it did suppress internalization and proliferation. These results suggest that E. risticii is internalized by receptor-mediated endocytosis and that productive infection by E. risticii does not depend on phagocytosis by the P388D1 cells. Although E. risticii did not bind to the

  20. Human Infection with Ehrlichia muris–like Pathogen, United States, 2007–20131

    PubMed Central

    Johnson, Diep K. Hoang; Schiffman, Elizabeth K.; Davis, Jeffrey P.; Neitzel, David F.; Sloan, Lynne M.; Nicholson, William L.; Fritsche, Thomas R.; Steward, Christopher R.; Ray, Julie A.; Miller, Tracy K.; Feist, Michelle A.; Uphoff, Timothy S.; Franson, Joni J.; Livermore, Amy L.; Deedon, Alecia K.; Theel, Elitza S.

    2015-01-01

    An Ehrlichia muris–like (EML) pathogen was detected among 4 patients in Minnesota and Wisconsin during 2009. We characterized additional cases clinically and epidemiologically. During 2004–2013, blood samples from 75,077 patients from all 50 United States were tested by PCR from the groEL gene for Ehrlichia spp. and Anaplasma phagocytophilum. During 2007–2013, samples from 69 (0.1%) patients were positive for the EML pathogen; patients were from 5 states: Indiana (1), Michigan (1), Minnesota (33), North Dakota (3), and Wisconsin (31). Most (64%) patients were male; median age was 63 (range 15–94) years; and all 69 patients reported likely tick exposure in Minnesota or Wisconsin. Fever, malaise, thrombocytopenia, and lymphopenia were the most common symptoms. Sixteen (23%) patients were hospitalized (median 4 days); all recovered, and 96% received doxycycline. Infection with the EML pathogen should be considered for persons reporting tick exposure in Minnesota or Wisconsin. PMID:26402378

  1. Tissue Distribution of the Ehrlichia muris-Like Agent in a Tick Vector

    PubMed Central

    Lynn, Geoffrey E.; Oliver, Jonathan D.; Nelson, Curtis M.; Felsheim, Roderick F.; Kurtti, Timothy J.; Munderloh, Ulrike G.

    2015-01-01

    Human pathogens transmitted by ticks undergo complex life cycles alternating between the arthropod vector and a mammalian host. While the latter has been investigated to a greater extent, examination of the biological interactions between microbes and the ticks that carry them presents an equally important opportunity for disruption of the disease cycle. In this study, we used in situ hybridization to demonstrate infection by the Ehrlichia muris-like organism, a newly recognized human pathogen, of Ixodes scapularis ticks, a primary vector for several important human disease agents. This allowed us to assess whole sectioned ticks for the patterns of tissue invasion, and demonstrate generalized dissemination of ehrlichiae in a variety of cell types and organs within ticks infected naturally via blood feeding. Electron microscopy was used to confirm these results. Here we describe a strong ehrlichial affinity for epithelial cells, neuronal cells of the synganglion, salivary glands, and male accessory glands. PMID:25781930

  2. Ehrlichia canis infection in a dog with no history of travel outside the United Kingdom.

    PubMed

    Wilson, H E; Mugford, A R; Humm, K R; Kellett-Gregory, L M

    2013-08-01

    A two-year-old female neutered Tibetan terrier was referred following a one-month history of lethargy, inappetence and pancytopenia, which had been poorly responsive to immunosuppressive and fluoroquinolone treatment. The dog was diagnosed with pure red cell aplasia and was found to be positive for Ehrlichia canis by both antibody titre measurement and polymerase chain reaction. The dog lived in London and had not travelled outside the UK. The dog was treated with doxycycline, prednisolone and ciclosporin, but died as a result of gastrointestinal tract haemorrhage. To the authors' knowledge, this represents the first reported case of Ehrlichia canis in a dog in the UK with no previous travel history. PMID:23718904

  3. Tissue distribution of the Ehrlichia muris-like agent in a tick vector.

    PubMed

    Lynn, Geoffrey E; Oliver, Jonathan D; Nelson, Curtis M; Felsheim, Roderick F; Kurtti, Timothy J; Munderloh, Ulrike G

    2015-01-01

    Human pathogens transmitted by ticks undergo complex life cycles alternating between the arthropod vector and a mammalian host. While the latter has been investigated to a greater extent, examination of the biological interactions between microbes and the ticks that carry them presents an equally important opportunity for disruption of the disease cycle. In this study, we used in situ hybridization to demonstrate infection by the Ehrlichia muris-like organism, a newly recognized human pathogen, of Ixodes scapularis ticks, a primary vector for several important human disease agents. This allowed us to assess whole sectioned ticks for the patterns of tissue invasion, and demonstrate generalized dissemination of ehrlichiae in a variety of cell types and organs within ticks infected naturally via blood feeding. Electron microscopy was used to confirm these results. Here we describe a strong ehrlichial affinity for epithelial cells, neuronal cells of the synganglion, salivary glands, and male accessory glands. PMID:25781930

  4. Epidemiological and molecular study of Ehrlichia canis in dogs in Bahia, Brazil.

    PubMed

    Carvalho, F S; Wenceslau, A A; Carlos, R S A; Albuquerque, G R

    2008-01-01

    The objective of the present article was an epidemiological and molecular study of Ehrlichia canis in dogs of Ilhéus and Itabuna in Bahia, as well as an evaluation of associated risk factors. Blood samples were collected from 153 dogs and DNA was extracted and analyzed by the nested-polymerase chain reaction, using one pair of primers to detect Ehrlichia bacteria and another pair to detect the presence of E. canis. Of the 153 animals, 12 (7.8%) were polymerase chain reaction-positive for E. canis, indicating the presence of the parasite in dogs of the Ilhéus-Itabuna microregion. The associated risk factors were exposure to tick-infested habitats and the fact that the dogs lived in the countryside. PMID:18752193

  5. Tandem betatron

    DOEpatents

    Keinigs, Rhonald K.

    1992-01-01

    Two betatrons are provided in tandem for alternately accelerating an electron beam to avoid the single flux swing limitation of conventional betatrons and to accelerate the electron beam to high energies. The electron beam is accelerated in a first betatron during a period of increasing magnetic flux. The eletron beam is extracted from the first betatron as a peak magnetic flux is reached and then injected into a second betatron at a time of minimum magnetic flux in the second betatron. The cycle may be repeated until the desired electron beam energy is obtained. In one embodiment, the second betatron is axially offset from the first betatron to provide for electron beam injection directly at the axial location of the beam orbit in the second betatron.

  6. Geographic distribution and genetic diversity of the Ehrlichia sp. from Panola Mountain in Amblyomma americanum

    PubMed Central

    Loftis, Amanda D; Mixson, Tonya R; Stromdahl, Ellen Y; Yabsley, Michael J; Garrison, Laurel E; Williamson, Phillip C; Fitak, Robert R; Fuerst, Paul A; Kelly, Daryl J; Blount, Keith W

    2008-01-01

    Background A novel Ehrlichia, closely related to Ehrlichia ruminantium, was recently discovered from Panola Mountain State Park, GA, USA. We conducted a study to determine if this agent was recently introduced into the United States. Methods We developed a sensitive PCR assay based on the conserved gltA (citrate synthase) gene and tested DNA samples extracted from 1964 field-collected and 1835 human-biting Amblyomma americanum from 23 eastern states of the USA. Results The novel agent was detected in 36 ticks collected from 10 states between 1998 and 2006. Infected ticks were collected both from vegetation (n = 14, 0.7%) and from humans (n = 22, 1.2%). Fragments of the conserved gltA gene and the variable map1 gene were sequenced from positive samples. Two distinct clades, with 10.5% nucleic acid divergence over the 730 bp map1 sequence, were identified. Conclusion These data suggest that the Panola Mountain Ehrlichia was not recently introduced to the United States; this agent has an extensive distribution throughout the range of its tick vector, has been present in some locations for several years, and displays genetic variability. Furthermore, people in several states were exposed to this agent through the bite of infected ticks, underscoring the potential public health risk of this emerging ehrlichiosis. PMID:18433500

  7. Tandem Couture

    PubMed Central

    Ericksen, Spencer S.; Boileau, Andrew J.

    2008-01-01

    Receptor subunits in the Cys-loop superfamily assemble to form channels as homopentamers or heteropentamers, expanding functional diversity through modularity. Expression of two or more compatible subunit types can lead to various receptor assemblies or subtypes. However, what may be good for diversity in vivo may be undesirable for the bench scientist, because we often wish to reduce our analyses to a single receptor subtype. By linking two or more subunits, creating tandems or concatamers, we can control stoichiometry and limit expression to exactly one receptor subtype. In this fashion, receptors with mixed subunit subtypes and heterozygous mutations can be separated from a mixture and can be described in detail. However, several recent studies have shown that this may be more easily conceived than accomplished, because several unforeseen problems have arisen. Concatamers can degrade, linkers can sometimes be clipped after or during translation, and one subunit may “loop out” or even become part of a second (now linked) pentamer with different characteristics. Some strategies have been developed to overcome these drawbacks, and the resultant new information that has begun to emerge has revitalized the study of these receptors in heterologous expression systems. PMID:17519509

  8. Molecular identification and characterization of Anaplasma platys and Ehrlichia canis in dogs in Mexico.

    PubMed

    Almazán, Consuelo; González-Álvarez, Vicente H; Fernández de Mera, Isabel G; Cabezas-Cruz, Alejandro; Rodríguez-Martínez, Rafael; de la Fuente, José

    2016-03-01

    The tick-borne pathogens Ehrlichia canis and Anaplasma platys are the causative agents of canine monocytic ehrlichiosis (CME) and canine cyclic thrombocytopenia (CCT). Although molecular evidence of E. canis has been shown, phylogenetic analysis of this pathogen has not been performed and A. platys has not been identified in Mexico, where the tick vector Rhipicephalus sanguineus sensu lato (s.l.) is common. The aim of this research was to screen, identify and characterize E. canis and A. platys by PCR and phylogenetic analysis in dogs from La Comarca Lagunera, a region formed by three municipalities, Torreon, Gomez-Palacio and Lerdo, in the Northern states of Coahuila and Durango, Mexico. Blood samples and five engorged R. sanguineus s.l. ticks per animal were collected from 43 females and 57 male dogs presented to veterinary clinics or lived in the dog shelter from La Comarca Lagunera. All the sampled dogs were apparently healthy and PCR for Anaplasma 16S rRNA, Ehrlichia 16S rRNA, and E. canis trp36 were performed. PCR products were sequenced and used for phylogenetic analysis. PCR products were successfully amplified in 31% of the samples using primers for Anaplasma 16S rRNA, while 10% and 4% amplified products using primers for Ehrlichia 16S rRNA and E. canis trp36 respectively. Subsequent sequencing and phylogenetic analyses of these products showed that three samples corresponded to A. platys and four to E. canis. Based on the analysis of trp36 we confirmed that the E. canis strains isolated from Mexico belong to a conservative clade of E. canis and are closely related to strains from USA. In conclusion, this is the first molecular identification of A. platys and the first molecular characterization and phylogenetic study of both A. platys and E. canis in dogs in Mexico. PMID:26615872

  9. First description of natural Ehrlichia canis and Anaplasma platys infections in dogs from Argentina.

    PubMed

    Eiras, Diego Fernando; Craviotto, María Belén; Vezzani, Darío; Eyal, Osnat; Baneth, Gad

    2013-03-01

    Bacteria belonging to the Anaplasmataceae family are vector transmitted agents that affect a variety of vertebrate hosts including the tick-borne pathogens Ehrlichia canis and Anaplasma platys, which cause canine monocytic ehrlichiosis and cyclic thrombocytopenia, respectively. These two infections, typically reported from tropical and sub-tropical regions, have not been previously reported in dogs from Argentina. A total of 86 blood samples from dogs with suspected rickettsial disease and 28 non-suspected dogs were studied. Analysis included evaluation of hematological findings, PCR for Ehrlichia and Anaplasma species and sequencing of the positive PCR products. E. canis was detected in the blood of six dogs and A. platys in eighteen. All the dogs categorized as non-suspected were negative by PCR. Co-infection with Hepatozoon canis and Babesia vogeli was documented. This first report of E. canis and A. platys infections in dogs from Argentina indicates that these tick-borne infections have a considerably broader range than previously recognized in South America. PMID:23273677

  10. Development of Loop-Mediated Isothermal Amplification (LAMP) Assays for Rapid Detection of Ehrlichia ruminantium

    PubMed Central

    2010-01-01

    Background The rickettsial bacterium Ehrlichia ruminantium is the causative agent of heartwater, a potential zoonotic disease of ruminants transmitted by ticks of the genus Amblyomma. The disease is distributed in nearly all of sub-Saharan Africa and some islands of the Caribbean, from where it threatens the American mainland. This report describes the development of two different loop-mediated isothermal amplification (LAMP) assays for sensitive and specific detection of E. ruminantium. Results Two sets of LAMP primers were designed from the pCS20 and sodB genes. The detection limits for each assay were 10 copies for pCS20 and 5 copies for sodB, which is at least 10 times higher than that of the conventional pCS20 PCR assay. DNA amplification was completed within 60 min. The assays detected 16 different isolates of E. ruminantium from geographically distinct countries as well as two attenuated vaccine isolates. No cross-reaction was observed with genetically related Rickettsiales, including zoonotic Ehrlichia species from the USA. LAMP detected more positive samples than conventional PCR but less than real-time PCR, when tested with field samples collected in sub-Saharan countries. Conclusions Due to its simplicity and specificity, LAMP has the potential for use in resource-poor settings and also for active screening of E. ruminantium in both heartwater-endemic areas and regions that are at risk of contracting the disease. PMID:21087521

  11. Serum DHEA-S increases in dogs naturally infected with Ehrlichia canis.

    PubMed

    Rondelli, M C H; Munhoz, T D; Catandi, P B; Freschi, C R; Palacios Junior, R J G; Machado, R Z; Tinucci-Costa, M

    2015-06-01

    Adrenocortical disturbances are expected in canine ehrlichiosis due to the immunological challenges caused by infection and consequent inflammation. Thus, this study aimed to evaluate the occurrence of adrenocortical hormonal alterations in dogs naturally infected with Ehrlichia canis (n = 21) as positively confirmed by the presence of anti-E. canis antibodies (Dot-ELISA) and nested PCR (nPCR). Serum dehydroepiandrosterone sulfate (DHEA-S) concentrations were assessed via ELISA before and one hour after ACTH stimulation. Another 10 healthy dogs were subjected to the same stimulation protocol and used as controls. The results revealed that baseline and post-ACTH DHEA-S concentrations were significantly greater in sick dogs, regardless of gender, and this finding illustrates the stress induced by naturally acquired ehrlichiosis in dogs. PMID:25956636

  12. [Ehrlichia canis infections of dogs in Germany. Epidemiology, diagnosis, therapy and prophylaxis].

    PubMed

    Gothe, R

    1998-11-01

    Between January and December 1997 infections with Ehrlichia canis were detected in 211 dogs in Germany. Of the 53 epidemiologically evaluable dogs, 19 animals born and raised in Germany had travelled with their owners abroad in endemic areas, 30 dogs originated from there and four dogs had never left Germany. As regards to the possible location of infection it has been registered that most dogs had been taken to countries of the Mediterranean Sea (Spain, France, Italy, Greece) or had been imported from there. On inquiry, ticks had been forwarded from four dogs only, which were determined as Rhipicephalus sanguineus. The subsequent serological investigation of these four dogs revealed a Rickettsia conorii infection in two of them. PMID:9857421

  13. First evidence of feline herpesvirus, calicivirus, parvovirus, and Ehrlichia exposure in Brazilian free-ranging felids.

    PubMed

    Filoni, Claudia; Catão-Dias, José Luiz; Bay, Gert; Durigon, Edison Luiz; Jorge, Rodrigo Silva Pinto; Lutz, Hans; Hofmann-Lehmann, Regina

    2006-04-01

    Serum samples from 18 pumas (Puma concolor), one ocelot (Leopardus pardalis), and two little spotted cats (Leopardus tigrinus) collected from free-ranging animals in Brazil between 1998 and 2004 were tested by indirect immunofluorescence (IFA) for antibodies to feline herpesvirus 1 (FHV 1), calicivirus (FCV), coronavirus (FCoV), parvo-virus (FPV), Ehrlichia canis, Anaplasma pha-gocytophilum, and Bartonella henselae. Serum samples also were tested, by Western blot and ELISA, for feline leukemia virus (FeLV) specific antibodies and antigen, respectively, by Western blot for antibodies to feline immunodeficiency virus (FIV), and by indirect ELISA for antibodies to puma lentivirus (PLV). Antibodies to FHV 1, FCV, FCoV, FPV, FeLV, FIV, PLV or related viruses, and to B. henselae were detected. Furthermore, high-titered antibodies to E. canis or a closely related agent were detected in a puma for the first time. PMID:16870878

  14. Proteomic Profiling of the Outer Membrane Fraction of the Obligate Intracellular Bacterial Pathogen Ehrlichia ruminantium

    PubMed Central

    Moumène, Amal; Marcelino, Isabel; Ventosa, Miguel; Gros, Olivier; Lefrançois, Thierry; Vachiéry, Nathalie

    2015-01-01

    The outer membrane proteins (OMPs) of Gram-negative bacteria play a crucial role in virulence and pathogenesis. Identification of these proteins represents an important goal for bacterial proteomics, because it aids in vaccine development. Here, we have developed such an approach for Ehrlichia ruminantium, the obligate intracellular bacterium that causes heartwater. A preliminary whole proteome analysis of elementary bodies, the extracellular infectious form of the bacterium, had been performed previously, but information is limited about OMPs in this organism and about their role in the protective immune response. Identification of OMPs is also essential for understanding Ehrlichia’s OM architecture, and how the bacterium interacts with the host cell environment. First, we developed an OMP extraction method using the ionic detergent sarkosyl, which enriched the OM fraction. Second, proteins were separated via one-dimensional electrophoresis, and digested peptides were analyzed via nano-liquid chromatographic separation coupled with mass spectrometry (LC-MALDI-TOF/TOF). Of 46 unique proteins identified in the OM fraction, 18 (39%) were OMPs, including 8 proteins involved in cell structure and biogenesis, 4 in transport/virulence, 1 porin, and 5 proteins of unknown function. These experimental data were compared to the predicted subcellular localization of the entire E. ruminantium proteome, using three different algorithms. This work represents the most complete proteome characterization of the OM fraction in Ehrlichia spp. The study indicates that suitable subcellular fractionation experiments combined with straightforward computational analysis approaches are powerful for determining the predominant subcellular localization of the experimentally observed proteins. We identified proteins potentially involved in E. ruminantium pathogenesis, which are good novel targets for candidate vaccines. Thus, combining bioinformatics and proteomics, we discovered new OMPs

  15. In vitro isolation and molecular characterization of an Ehrlichia canis strain from São Paulo, Brazil

    PubMed Central

    Aguiar, Daniel M.; Hagiwara, Mitika K.; Labruna, Marcelo B.

    2008-01-01

    An Ehrlichia canis isolate was obtained from an naturally infected dog exhibiting clinical signs of ehrlichiosis in São Paulo Municipality, state of São Paulo, Brazil. The isolate was characterized by PCR and DNA sequencing of portions of the ehrlichial genes dsb, 16SrRNA, and p28. Partial dsb and 16S rRNA sequences were identical to three and five other E. canis strains, respectively, from different countries and continents (including North America, Africa, Asia and Europe). Conversely, the p28 partial sequence for this E. canis (São Paulo) differed by 1, 2, and 2 nucleotides from the corresponding sequences of the E. canis strains Jake (from USA), Oklahoma (USA), and VHE (Venezuela), respectively. The results in this study indicate that E. canis is the only recognized Ehrlichia species infecting dogs in Brazil. PMID:24031251

  16. Molecular detection of novel Anaplasmataceae closely related to Anaplasma platys and Ehrlichia canis in the dromedary camel (Camelus dromedarius).

    PubMed

    Bastos, Armanda D S; Mohammed, Osama B; Bennett, Nigel C; Petevinos, Charalambos; Alagaili, Abdulaziz N

    2015-09-30

    Serological surveys have confirmed Anaplasma marginale and Anaplasma phagocytophilum infections in dromedary camels, but molecular surveys and genetic characterisation of camel-associated Anaplasma species are lacking. In this study, we detected tick-borne Anaplasmataceae in 30 of 100 (30%) healthy dromedary camels screened using a combined 16S rRNA-groEL PCR-sequencing approach. Nucleotide sequencing confirmed Anaplasmataceae genome presence in 28 of the 33 16S rRNA PCR-positive samples, with two additional positive samples, for which 16S rRNA sequence data were ambiguous, being identified by groEL gene characterisation. Phylogenetic analyses of a 1289 nt segment of the 16S rRNA gene confirmed the presence of a unique Ehrlichia lineage and a discrete Anaplasma lineage, comprising three variants, occurring at an overall prevalence of 4% and 26%, respectively. Genetic characterisation of an aligned 559 nt groEL gene region revealed the camel-associated Anaplasma and Ehrlichia lineages to be novel and most closely related to Anaplasma platys and Ehrlichia canis. Based on the confirmed monophyly, minimum pairwise genetic distances between each novel lineage and its closest sister taxon, and the inability to isolate the bacteria, we propose that Candidatus status be assigned to each. This first genetic characterisation of Anaplasmataceae from naturally infected, asymptomatic dromedary camels in Saudi Arabia confirms the presence of two novel lineages that are phylogenetically linked to two pathogenic canid species of increasing zoonotic concern. PMID:26096752

  17. Rangelia vitalii, Babesia spp. and Ehrlichia spp. in dogs in Passo Fundo, state of Rio Grande do Sul, Brazil.

    PubMed

    Gottlieb, Juliana; André, Marcos Rogério; Soares, João Fábio; Gonçalves, Luiz Ricardo; Tonial de Oliveira, Mateus; Costa, Marcio Machado; Labruna, Marcelo Bahia; Bortolini, Carlos Eduardo; Machado, Rosangela Zacarias; Vieira, Maria Isabel Botelho

    2016-06-14

    Pathogens transmitted by ticks are an emerging problem worldwide, this study aimed to diagnose the causal agents of infection in dogs presenting suspected hemoparasitoses. Fifty-eight dogs with clinical signs such as depression, hemorrhagic diathesis and fever were evaluated regarding clinical presentation, hemogram, blood smears and serological tests, using the indirect immunofluorescence method for the agents Babesia vogeli and Ehrlichia canis and conventional PCR for Babesia spp. (gene 18S rRNA), Rangelia vitalii (gene 18S rRNA) and Ehrlichia spp. (gene dsb). Five (8.6%) of the 58 dogs were serologically positive for Babesia spp. and three (5.1%) for E. canis. Four dogs (6.8%) were positive for R. vitalii through the molecular diagnosis. The PCR products were sequenced and the DNA from R. vitalii was found to be 99% genetically identical to samples of R. vitalii that had been isolated in Brazil. No presence of Babesia spp. or E. canis was observed through PCR on the dogs evaluated here. The results indicate the presence of R. vitalii and exposure to Babesia spp. and Ehrlichia spp. among the dogs analyzed. PMID:27304518

  18. Rangelia vitalii, Babesia spp. and Ehrlichia spp. in dogs in Passo Fundo, state of Rio Grande do Sul, Brazil.

    PubMed

    Gottlieb, Juliana; André, Marcos Rogério; Soares, João Fábio; Gonçalves, Luiz Ricardo; Tonial de Oliveira, Mateus; Costa, Marcio Machado; Labruna, Marcelo Bahia; Bortolini, Carlos Eduardo; Machado, Rosangela Zacarias; Vieira, Maria Isabel Botelho

    2016-06-14

    Pathogens transmitted by ticks are an emerging problem worldwide, this study aimed to diagnose the causal agents of infection in dogs presenting suspected hemoparasitoses. Fifty-eight dogs with clinical signs such as depression, hemorrhagic diathesis and fever were evaluated regarding clinical presentation, hemogram, blood smears and serological tests, using the indirect immunofluorescence method for the agents Babesia vogeli and Ehrlichia canis and conventional PCR for Babesia spp. (gene 18S rRNA), Rangelia vitalii (gene 18S rRNA) and Ehrlichia spp. (gene dsb). Five (8.6%) of the 58 dogs were serologically positive for Babesia spp. and three (5.1%) for E. canis. Four dogs (6.8%) were positive for R. vitalii through the molecular diagnosis. The PCR products were sequenced and the DNA from R. vitalii was found to be 99% genetically identical to samples of R. vitalii that had been isolated in Brazil. No presence of Babesia spp. or E. canis was observed through PCR on the dogs evaluated here. The results indicate the presence of R. vitalii and exposure to Babesia spp. and Ehrlichia spp. among the dogs analyzed. PMID:27334817

  19. Tandem mobile robot system

    DOEpatents

    Buttz, James H.; Shirey, David L.; Hayward, David R.

    2003-01-01

    A robotic vehicle system for terrain navigation mobility provides a way to climb stairs, cross crevices, and navigate across difficult terrain by coupling two or more mobile robots with a coupling device and controlling the robots cooperatively in tandem.

  20. Fatal Monocytic Ehrlichiosis in Woman, Mexico, 2013.

    PubMed

    Sosa-Gutierrez, Carolina G; Solorzano-Santos, Fortino; Walker, David H; Torres, Javier; Serrano, Carlos A; Gordillo-Perez, Guadalupe

    2016-05-01

    Human monocytic ehrlichiosis is a febrile illness caused by Ehrlichia chaffeensis, an intracellular bacterium transmitted by ticks. In Mexico, a case of E. chaffeensis infection in an immunocompetent 31-year-old woman without recognized tick bite was fatal. This diagnosis should be considered for patients with fever, leukopenia, thrombocytopenia, and elevated liver enzyme levels. PMID:27088220

  1. Fatal Monocytic Ehrlichiosis in Woman, Mexico, 2013

    PubMed Central

    Sosa-Gutierrez, Carolina G.; Solorzano-Santos, Fortino; Walker, David H.; Torres, Javier; Serrano, Carlos A.

    2016-01-01

    Human monocytic ehrlichiosis is a febrile illness caused by Ehrlichia chaffeensis, an intracellular bacterium transmitted by ticks. In Mexico, a case of E. chaffeensis infection in an immunocompetent 31-year-old woman without recognized tick bite was fatal. This diagnosis should be considered for patients with fever, leukopenia, thrombocytopenia, and elevated liver enzyme levels. PMID:27088220

  2. Isolation and Short-Term Persistence of Ehrlichia ewingii in Cell Culture.

    PubMed

    Killmaster, Lindsay F; Levin, Michael L

    2016-07-01

    Ehrlichia ewingii is the causative agent of human and canine granulocytic ehrlichiosis. Since its discovery in 1970, little work has been done to characterize the pathogen or study the transmission dynamics due to the inability to grow the agent in vitro. The aim of this study was to assess the suitability of multiple cell lines and media formulations for propagation of E. ewingii in cell culture. In this study, we present an overview of attempts to isolate E. ewingii from the buffy coat of goats naturally infected by Amblyomma americanum ticks, as well as a methodology for maintaining the pathogen for up to 16 weeks in culture. The most promising results were seen with HL-60 cells differentiated by the addition of 1.5% DMSO to the media and supplemented with 8 mM l-glutamine. Cultures were passaged multiple times, and fluorescence and morulae were observed by indirect fluorescent antibody test and Diff-Quik staining. It is our hope that this information will provide a foundation for future attempts to propagate and maintain E. ewingii in cell culture. PMID:27228133

  3. Colorimetric Detection of Ehrlichia Canis via Nucleic Acid Hybridization in Gold Nano-Colloids

    PubMed Central

    Muangchuen, Ajima; Chaumpluk, Piyasak; Suriyasomboon, Annop; Ekgasit, Sanong

    2014-01-01

    Canine monocytic ehrlichiosis (CME) is a major thick-bone disease of dog caused by Ehrlichia canis. Detection of this causal agent outside the laboratory using conventional methods is not effective enough. Thus an assay for E. canis detection based on the p30 outer membrane protein gene was developed. It was based on the p30 gene amplification using loop-mediated isothermal DNA amplification (LAMP). The primer set specific to six areas within the target gene were designed and tested for their sensitivity and specificity. Detection of DNA signals was based on modulation of gold nanoparticles' surface properties and performing DNA/DNA hybridization using an oligonucleotide probe. Presence of target DNA affected the gold colloid nanoparticles in terms of particle aggregation with a plasmonic color change of the gold colloids from ruby red to purple, visible by the naked eye. All the assay steps were completed within 90 min including DNA extraction without relying on standard laboratory facilities. This method was very specific to target bacteria. Its sensitivity with probe hybridization was sufficient to detect 50 copies of target DNA. This method should provide an alternative choice for point of care control and management of the disease. PMID:25111239

  4. Molecular Diagnosis of Ehrlichia canis in Dogs and Ticks Rhipicephalus sanguineus (Acari: Ixodidae) in Yucatan, Mexico.

    PubMed

    Pat-Nah, Henry; Rodriguez-Vivas, Roger Ivan; Bolio-Gonzalez, Manuel Emilio; Villegas-Perez, Sandra Luz; Reyes-Novelo, Enrique

    2015-01-01

    Ehrlichia canis is the etiological agent behind canine monocytic ehrlichiosis, and the tick Rhipicephalus sanguineus (Latreille) is its main vector. Blood smear and nested polymerase chain reaction (PCR) techniques were used to identify E. canis infection in dogs and R. sanguineus, and explore factors possibly associated with infection in dogs in Yucatan, Mexico. Blood samples were taken and ticks R. sanguineus collected from 50 dogs (10 house dogs and 40 in an animal control center). Data were collected on dog age, sex, body condition, and signs associated with platelet deficiencies (epistaxis). Blood smears were analyzed to identify E. canis morulae and generate platelet counts. Nested PCR analysis was done on blood samples and 200 ticks. A χ(2) test was done to identify factors associated with the E. canis infection in the tested dogs. The overall prevalence for infection, as determined by PCR, was 36% (18 out of 50). All positive dogs were from samples collected from the animal shelter, representing prevalence, for this sampling site, of 45% (18 out of 40). Morulae in monocytes were identified in only 4% of samples. Dog origin (i.e. animal control center) was the only variable associated with E. canis infection (P < 0.01). Male ticks had a higher (P < 0.05) infection rate than female ticks (24.5 vs 13.5%). It is concluded that E. canis infection is present in both dogs and the brown dog ticks R. sanguineus in Yucatan, Mexico. PMID:26336286

  5. Iron metabolism and oxidative profile of dogs naturally infected by Ehrlichia canis: Acute and subclinical disease.

    PubMed

    Bottari, Nathieli B; Crivellenti, Leandro Z; Borin-Crivellenti, Sofia; Oliveira, Jéssica R; Coelho, Stefanie B; Contin, Catarina M; Tatsch, Etiane; Moresco, Rafael N; Santana, Aureo E; Tonin, Alexandre A; Tinucci-Costa, Mirela; Da Silva, Aleksandro S

    2016-03-01

    The aim of this study was to evaluate the oxidant profile and iron metabolism in serum of dogs infected by Ehrlichia canis. Banked sera samples of dogs were divided into two groups: negative control (n = 17) and infected by E. canis on acute (n = 24), and subclinical (n = 18) phases of the disease. The eritrogram, leucogram, and platelet counts were evaluate as well as iron, ferritin, and transferrin levels, latent iron binding capacity (LIBC), and transferrin saturation index (TSI) concentration. In addition, the advanced oxidation protein products (AOPP) and ferric reducing ability of plasma (FRAP) in sera were also analyzed. Blood samples were examined for the presence of E. canis by PCR techniques. History and clinical signals were recorded for each dog. During the acute phase of the disease, infected animals showed thrombocytopenia and anemia when compared to healthy animals (P < 0.05) as a consequence of lower iron levels. Ferritin and transferrin levels were higher in both phases (acute and subclinical) of the disease. The AOPP and FRAP levels increased in infected animals on the acute phase; however, the opposite occurred in the subclinical phase. We concluded that dogs naturally infected by E. canis showed changes in the iron metabolism and developed an oxidant status in consequence of disease pathophysiology. PMID:26724737

  6. First record of autochthonous canine ehrlichiosis caused by Ehrlichia canis in Romania.

    PubMed

    Morar, Doru; Dărăbuş, Gheorghe; Imre, Mirela; Ilie, Marius Stelian; Imre, Kálmán

    2015-06-01

    This case study describes the first genetically confirmed and clinically manifested autochthonous Ehrlichia canis infection in a 9-year-old female mixed-breed dog from Romania. Health screening of the dog included clinical examination, evaluation of stained peripheral blood smear and hematologic variables, as well as serologic testing and molecular analysis. Clinical signs included fever, apathy, dehydration, pale mucous membranes, and weakness. The microscopic examination of the blood smear and immunologic assays for Borrelia burgdorferi, Anaplasma phagocytophilum, and E canis antibodies, and for Dirofilaria immitis antigen yielded negative results. Hematologic abnormalities included moderate nonregenerative anemia, leucopenia with neutropenia, and moderate thrombocytopenia. The biochemical abnormalities identified were hypoalbuminemia, and mildly increased serum enzyme activities of AST and ALT. In addition, increased urea and creatinine levels associated with low urine specific gravity and proteinuria were also present. Nested PCR amplification of the partial E canis 16S rRNA gene demonstrated the presence of this rickettsial pathogen in the dog's blood, which subsequently was confirmed through sequencing based on the 100% homology with GenBank deposited E canis isolates. After specific treatment with doxycycline (10 mg/kg, orally, SID) for one month, the proteinuria, and hematologic and serum biochemical abnormalities with the exception of mild azotemia resolved. This report supports the geographical expansion of canine ehrlichiosis caused by E canis in nonendemic regions of Europe. PMID:25867940

  7. Molecular evidence of Ehrlichia canis and Rickettsia massiliae in ixodid ticks of carnivores from South Hungary.

    PubMed

    Hornok, Sándor; Fuente, José; Horváth, Gábor; Fernández de Mera, Isabel G; Wijnveld, Michiel; Tánczos, Balázs; Farkas, Róbert; Jongejan, Frans

    2013-03-01

    To monitor the emergence of thermophilic, Mediterranean ixodid tick species and tick-borne pathogens in southern Hungary, 348 ticks were collected from shepherd dogs, red foxes and golden jackals during the summer of 2011. Golden jackals shared tick species with both the dog and the red fox in the region. Dermacentor nymphs were collected exclusively from dogs, and the sequence identification of these ticks indicated that dogs are preferred hosts of both D. reticulatus and D. marginatus nymphs, unlike previously reported. Subadults of three ixodid species were selected for reverse line blot hybridisation (RLB) analysis to screen their vector potential for 40 pathogens/groups. Results were negative for Anaplasma, Babesia and Theileria spp. Investigation of D. marginatus nymphs revealed the presence of Ehrlichia canis, Rickettsia massiliae and Borrelia afzelii for the first time in this tick species. These findings broaden the range of those tick-borne agents, which are typically transmitted by Rhipicephalus sanguineus, but may also have Dermacentor spp. as potential or alternative vectors. Ehrlichiacanis was also newly detected in Ixodes canisuga larvae from red foxes. In absence of transovarial transmission in ticks this implies that Eurasian red foxes may play a reservoir role in the epidemiology of canine ehrlichiosis. PMID:23439290

  8. Tandem Air Propellers - II

    NASA Technical Reports Server (NTRS)

    Lesley, E. P.

    1939-01-01

    Tests of three-blade, adjustable-pitch counterrotating tandem model propellers, adjusted to absorb equal power at maximum efficiency of the combination, were made at Stanford University. The aerodynamic characteristics, for blade-angle settings of 15, 25, 35, 45, 55, and 65 degrees at 0.75R of the forward propeller and for diameters spacings of 8-1/2, 15 and 30% were compared with those of three-blade and six-blade propellers of the same blade form. It was found that, in order to realize the condition of equal power at maximum efficiency, the blade angles for the rear propeller must be generally less than for the forward propeller, the difference increasing the blade angle. The tests showed that, at maximum efficiency, the tandem propellers absorb about double the power of three-blade propellers and about 8% more power than six-blade propellers having the pitch of the forward propeller of the tandem combination. The maximum efficiency of the tandem propellers was found to be from 2-15% greater than for six-blade propellers, the difference varying directly with blade angle. It was also found that the maximum efficiency of the tandem propellers was greater than that of a three-blade propeller for blade angles at 0.75R of 25 degrees or more. The difference in maximum efficiency again varied directly with blade angle, being about 9% for 65 degrees at 0.75R.

  9. Canine infection with Dirofilaria immitis, Borrelia burgdorferi, Anaplasma spp., and Ehrlichia spp. in the United States, 2010–2012

    PubMed Central

    2014-01-01

    Background The geographic distribution of canine infection with vector-borne disease agents in the United States appears to be expanding. Methods To provide an updated assessment of geographic trends in canine infection with Dirofilaria immitis, Borrelia burgdorferi, Ehrlichia spp., and Anaplasma spp., we evaluated results from an average of 3,588,477 dogs tested annually by veterinarians throughout the United States from 2010 – 2012. Results As in an earlier summary report, the percent positive test results varied by agent and region, with antigen of D. immitis and antibody to Ehrlichia spp. most commonly identified in the Southeast (2.9% and 3.2%, respectively) and antibody to both B. burgdorferi and Anaplasma spp. most commonly identified in the Northeast (13.3% and 7.1%, respectively) and upper Midwest (4.4% and 3.9%, respectively). Percent positive test results for D. immitis antigen were lower in every region considered, including in the Southeast, than previously reported. Percent positive test results for antibodies to B. burgdorferi and Ehrlichia spp. were higher nationally than previously reported, and, for antibodies to Anaplasma spp., were higher in the Northeast but lower in the Midwest and West, than in the initial report. Annual reports of human cases of Lyme disease, ehrlichiosis, and anaplasmosis were associated with percent positive canine test results by state for each respective tick-borne disease agent (R2 = 0.701, 0.457, and 0.314, respectively). Within endemic areas, percent positive test results for all three tick-borne agents demonstrated evidence of geographic expansion. Conclusions Continued national monitoring of canine test results for vector-borne zoonotic agents is an important tool for accurately mapping the geographic distribution of these agents, and greatly aids our understanding of the veterinary and public health threats they pose. PMID:24886589

  10. Tandem mirror fusion research

    SciTech Connect

    Baldwin, D.E.

    1983-12-02

    The tandem mirror program has evolved considerably in the last decade. Of significance is the viable reactor concept embodied in the MARS design. An aggressive experimental program, culminating in the operation of MFTF-B in late 1986, will provide a firm basis for refining the MARS design as necessary for constructing a reactor prototype in the 1990s.

  11. Tandem BRCT Domains

    PubMed Central

    Mesquita, Rafael D.; Woods, Nicholas T.; Seabra-Junior, Eloy S.; Monteiro, Alvaro N.A.

    2010-01-01

    The cell’s ability to sense and respond to specific stimuli is a complex system derived from precisely regulated protein-protein interactions. Some of these protein-protein interactions are mediated by the recognition of linear peptide motifs by protein modular domains. BRCT (BRCA1 C-terminal) domains and their linear motif counterparts, which contain phosphoserines, are one such pair-wise interaction system that seems to have evolved to serve as a surveillance system to monitor threats to the cell’s genetic integrity. Evidence indicates that BRCT domains found in tandem can cooperate to provide sequence-specific binding of phosphorylated peptides as is the case for the breast and ovarian cancer susceptibility gene BRCA1 and the PAX transcription factor–interacting protein PAXIP1. Particular interest has been paid to tandem BRCT domains as “readers” of signaling events in the form of phosphorylated serine moieties induced by the activation of DNA damage response kinases ATM, ATR, and DNA-PK. However, given the diversity of tandem BRCT-containing proteins, questions remain as to the origin and evolution of this domain. Here, we discuss emerging views of the origin and evolving roles of tandem BRCT domain repeats in the DNA damage response. PMID:21533002

  12. Evaluation of an attenuated strain of Ehrlichia canis as a vaccine for canine monocytic ehrlichiosis.

    PubMed

    Rudoler, Nir; Baneth, Gad; Eyal, Osnat; van Straten, Michael; Harrus, Shimon

    2012-12-17

    Canine monocytic ehrlichiosis is an important tick-borne disease worldwide. No commercial vaccine for the disease is currently available and tick control is the main preventive measure against the disease. The aim of this study was to evaluate the potential of a multi-passaged attenuated strain of Ehrlichia canis to serve as a vaccine for canine monocytic ehrlichiosis, and to assess the use of azithromycin in the treatment of acute ehrlichiosis. Twelve beagle dogs were divided into 3 groups of 4 dogs. Groups 1 and 2 were inoculated (vaccinated) with an attenuated strain of E. canis (#611A) twice or once, respectively. The third group consisted of naïve dogs which served as controls. All 3 groups were challenged with a wild virulent strain of E. canis by administering infected dog-blood intravenously. Transient thrombocytopenia was the only hematological abnormality observed following inoculation of dogs with the attenuated strain. Challenge with the virulent strain resulted in severe disease in all 4 control dogs while only 3 of 8 vaccinated dogs presented mild transient fever. Furthermore, the mean blood rickettsial load was significantly higher in the control group (27-92-folds higher during days 14-19 post challenge with the wild the strain) as compared to the vaccinated dogs. The use of azithromycin was assessed as a therapeutic agent for the acute disease. Four days treatment resulted in further deterioration of the clinical condition of the dogs. Molecular comparison of 4 genes known to express immunoreactive proteins and virulence factors (p30, gp19, VirB4 and VirB9) between the attenuated strain and the challenge wild strain revealed no genetic differences between the strains. The results of this study indicate that the attenuated E. canis strain may serve as an effective and secure future vaccine for canine ehrlichiosis. PMID:23072894

  13. Inhibitory effect of interferon gamma on frequency of Ehrlichia canis-infected cells in vitro.

    PubMed

    Tajima, Tomoko; Wada, Makoto

    2013-12-15

    Ehrlichia canis is an obligate intracellular bacterium that infects the macrophage-monocyte cells of dogs, causing canine monocytic ehrlichiosis. Interferon-γ (IFN-γ), along with other cytokines, mediates the immune response to such intracellular bacterial invasions. To determine the role of IFN-γ in the immunity of dogs to E. canis infection, peripheral blood mononuclear cells (PBMC) and white blood cells (WBC) were collected from E. canis-infected dogs and added to a culture of E. canis in DH82 cells. The number of E. canis inclusion-positive cells was significantly reduced in cultures containing PBMC and WBC from E. canis-infected dogs compared to uninfected dogs. However, this resistance was inhibited by the addition of an anti-dog IFN-γ antibody. Resistance was also observed when PBMC were added to the Cell Culture Inserts, which prohibited contact of PBMC to DH82 cells, while allowed the diffusion of soluble cell products. The results of this study indicate that resistance was not dependent on cell to cell contact, but was associated with soluble cell products, such as IFN-γ. The addition of recombinant canine IFN-γ to the E. canis culture also reduced the number of infected cells. A commercial recombinant canine IFN-γ, which is sold in Japan, was also effective at reducing E. canis-infected cell number. These results indicate that IFN-γ has an inhibitory effect on the frequency of E. canis-infected cells in vitro and that contact between effector and target cells is not necessary for the resistance. PMID:24148826

  14. Seroprevalence of Ehrlichia ruminantium antibodies and its associated risk factors in indigenous goats of South Africa.

    PubMed

    Mdladla, Khanyisile; Dzomba, Edgar F; Muchadeyi, Farai C

    2016-03-01

    The present study investigated the seroprevalence of antibodies to Ehrlichia ruminantium and the associated risk factors in goats from five different farming provinces of South Africa. Sera collected from 686 goats of the commercial meat type (n=179), mohair type (n=9), non-descript indigenous goats from Eastern Cape (n=56), KwaZulu-Natal (n=209), Limpopo (n=111), North West (n=61) and Northern Cape (n=11) provinces and a feral Tankwa goat (n=50) were tested for the presence of immunoglobulin G (IgG) antibodies to antigens of E. ruminantium using the indirect fluorescent-antibody test (IFAT). Fifty two percent of these goats had ticks. The overall seroprevalence of antibodies to E. ruminantium was 64.87% (445/686) with the highest seroprevalence reported for Limpopo (95.50%) and lowest for Northern Cape (20.29%). Highest seroprevalence for antibodies to E. ruminantium was observed in goats from endemic regions (76.09%), and from smallholder production systems (89.54%). High seroprevalence was also observed in non-descript indigenous goats (85.04%), adult goat (69.62%), in does (67.46%) and goats infested with ticks (85.79%). The logistic model showed a gradient of increasing risk for commercial meat type Savanna (OR=3.681; CI=1.335-10.149) and non-descript indigenous (OR=3.466; CI=1.57-7.645) compared to Boer goats and for goats from the smallholder production system (OR=2.582; CI=1.182-5.639) and those with ticks (OR=3.587; CI=2.105-6.112). Results from this study showed that E. ruminantium infections were prevalent but were widely and unevenly distributed throughout South Africa. Findings from the study facilitate identification and mapping of risk areas for heartwater and its endeminicity in South Africa and should be taken into consideration for future disease control strategies and local goat improvement programs. PMID:26829905

  15. Recombinant Major Antigenic Protein 2 of Ehrlichia canis: a Potential Diagnostic Tool

    PubMed Central

    Alleman, A. Rick; McSherry, Leo J.; Barbet, Anthony F.; Breitschwerdt, Edward B.; Sorenson, Heather L.; Bowie, Michael V.; Bélanger, Myriam

    2001-01-01

    The major antigenic protein 2 (MAP2) of Ehrlichia canis was cloned and expressed. The recombinant protein was characterized and tested in an enzyme-linked immunosorbent assay (ELISA) format for potential application in the serodiagnosis of canine monocytic ehrlichiosis. The recombinant protein, which contained a C-terminal polyhistidine tag, had a molecular mass of approximately 26 kDa. The antigen was clearly identified by Western immunoblotting using antihistidine antibody and immune serum from an experimentally infected dog. The recombinant MAP2 (rMAP2) was tested in an ELISA format using 141 serum samples from E. canis immunofluorescent antibody (IFA)-positive and IFA-negative dogs. Fifty-five of the serum samples were from dogs experimentally or naturally infected with E. canis and were previously demonstrated to contain antibodies reactive with E. canis by indirect immunofluorescence assays. The remaining 86 samples, 33 of which were from dogs infected with microorganisms other than E. canis, were seronegative. All of the samples from experimentally infected animals and 36 of the 37 samples from naturally infected animals were found to contain antibodies against rMAP2 of E. canis in the ELISA. Only 3 of 53 IFA-negative samples tested positive on the rMAP2 ELISA. There was 100% agreement among IFA-positive samples from experimentally infected animals, 97.3% agreement among IFA-positive samples from naturally infected animals, and 94.3% agreement among IFA-negative samples, resulting in a 97.2% overall agreement between the two assays. These data suggest that rMAP2 of E. canis could be used as a recombinant test antigen for the serodiagnosis of canine monocytic ehrlichiosis. PMID:11427559

  16. Draft Genome Sequences of Three Strains of Ehrlichia ruminantium, a Tick-Borne Pathogen of Ruminants, Isolated from Zimbabwe, The Gambia, and Ghana.

    PubMed

    Nakao, Ryo; Jongejan, Frans; Sugimoto, Chihiro

    2016-01-01

    The rickettsial bacterium Ehrlichia ruminantium is the causative pathogen of heartwater in ruminants. Here, we report the draft genome sequences of three strains of E. ruminantium, namely, the Crystal Springs strain from Zimbabwe, the Kerr Seringe strain from The Gambia, and the Sankat 430 strain from Ghana. PMID:27313287

  17. Draft Genome Sequences of Three Strains of Ehrlichia ruminantium, a Tick-Borne Pathogen of Ruminants, Isolated from Zimbabwe, The Gambia, and Ghana

    PubMed Central

    Nakao, Ryo; Jongejan, Frans

    2016-01-01

    The rickettsial bacterium Ehrlichia ruminantium is the causative pathogen of heartwater in ruminants. Here, we report the draft genome sequences of three strains of E. ruminantium, namely, the Crystal Springs strain from Zimbabwe, the Kerr Seringe strain from The Gambia, and the Sankat 430 strain from Ghana. PMID:27313287

  18. Host surveys, ixodid tick biology and transmission scenarios as related to the tick-borne pathogen, Ehrlichia canis

    PubMed Central

    Stich, R. W.; Schaefer, John J.; Bremer, William G.; Needham, Glen R.; Jittapalapong, Sathaporn

    2008-01-01

    The ehrlichioses have been subject to increasing interest from veterinary and public health perspectives, but experimental studies of these diseases and their etiologic agents can be challenging. Ehrlichia canis, the primary etiologic agent of canine monocytic ehrlichiosis, is relatively well characterized and offers unique advantages and opportunities to study interactions between a monocytotropic pathogen and both its vertebrate and invertebrate hosts. Historically, advances in tick-borne disease control strategies have typically followed explication of tick-pathogen-vertebrate interactions, thus it is reasonable to expect novel, more sustainable approaches to control of these diseases as the transmission of their associated infections are investigated at the molecular through ecological levels. Better understanding of the interactions between E. canis and its canine and tick hosts would also elucidate similar interactions for other Ehrlichia species as well as the potential roles of canine sentinels, reservoirs and models of tick-borne zoonoses. This article summarizes natural exposure studies and experimental investigations of E. canis in the context of what is understood about biological vectors of tick-borne Anaplasmataceae. PMID:18963493

  19. Survey of Ehrlichia canis, Babesia spp. and Hepatozoon spp. in dogs from a semiarid region of Brazil.

    PubMed

    Rotondano, Tereza Emmanuelle de Farias; Almeida, Herta Karyanne Araújo; Krawczak, Felipe da Silva; Santana, Vanessa Lira; Vidal, Ivana Fernandes; Labruna, Marcelo Bahia; de Azevedo, Sérgio Santos; Ade lmeida, Alzira Maria Paiva; de Melo, Marcia Almeida

    2015-01-01

    This study assessed the occurrence of Ehrlichia spp., Babesia spp. and Hepatozoon spp. infections in 100 tick-harboring dogs from a semiarid region of the State of Paraíba, Northeastern Brazil. Blood samples and ticks were collected from the animals, and a questionnaire was submitted to dog owners to obtain general data. Blood samples were used to perform hemogram, direct blood smear and immunological and molecular hemoparasite detection. The 1,151 ticks collected were identified as Rhipicephalus sanguineus; direct smears revealed E. canis-like morulae in the monocytes of 4% (4/100) of the non-vaccinated female dogs, and 34% and 25% of the dogs tested positive for Ehrlichia canis by indirect immunofluorescence assay (IFA) and polymerase chain reaction (PCR), respectively. Blood smear examination revealed Babesia-suggestive merozoites in the erythrocytes of 2% (2/100) of the animals. Babesia vogeli was detected by PCR in ten animals (10%) and was correlated with young age (p = 0.007) and thrombocytopenia (p = 0.01). None of the animals showed Hepatozoon spp. positivity. These results indicate that E. canis is the main tick-borne canine pathogen in the study area and provide the first report of B. vogeli infection in dogs from Paraiba State. PMID:25909253

  20. Prevalence and diversity of Babesia, Hepatozoon, Ehrlichia, and Bartonella in wild and domestic carnivores from Zambia, Africa.

    PubMed

    Williams, Brianna M; Berentsen, Are; Shock, Barbara C; Teixiera, Maria; Dunbar, Michael R; Becker, Matthew S; Yabsley, Michael J

    2014-03-01

    A molecular survey was conducted for several hemoparasites of domestic dogs and three species of wild carnivores from two sites in Zambia. Three Babesia spp. were detected including Babesia felis and Babesia leo in lions (Panthera leo) and a Babesia sp. (similar to Babesia lengau) in spotted hyenas (Crocuta crocuta) and a single lion. All wild dogs (Lycaon pictus) and domestic dogs were negative for Babesia. High prevalences for Hepatozoon were noted in all three wild carnivores (38-61%) and in domestic dogs (13%). Significantly higher prevalences were noted in hyenas and wild dogs compared with domestic dogs and lions. All carnivores were PCR negative for Ehrlichia canis, Ehrlichia ewingii, and Bartonella spp. Overall, high prevalences and diversity of Babesia and Hepatozoon were noted in wild carnivores from Zambia. This study is the first molecular characterization of Babesia from any hyena species and is the first report of a Babesia sp. closely related to B. lengau, a parasite previously only reported from cheetahs (Acinonyx jubatus), in lions and hyenas. Although usually benign in wild carnivores, these hemoparasites can be pathogenic under certain circumstances. Importantly, data on vectors for these parasites are lacking, so studies are needed to identify vectors as well as determine transmission routes, infection dynamics, and host specificity of these hemoparasites in wildlife in Africa and also the risk of transmission between domestic animals and wildlife. PMID:24363181

  1. Tandem resonator reflectance modulator

    DOEpatents

    Fritz, I.J.; Wendt, J.R.

    1994-09-06

    A wide band optical modulator is grown on a substrate as tandem Fabry-Perot resonators including three mirrors spaced by two cavities. The absorption of one cavity is changed relative to the absorption of the other cavity by an applied electric field, to cause a change in total reflected light, as light reflecting from the outer mirrors is in phase and light reflecting from the inner mirror is out of phase with light from the outer mirrors. 8 figs.

  2. Tandem resonator reflectance modulator

    DOEpatents

    Fritz, Ian J.; Wendt, Joel R.

    1994-01-01

    A wide band optical modulator is grown on a substrate as tandem Fabry-Perot resonators including three mirrors spaced by two cavities. The absorption of one cavity is changed relative to the absorption of the other cavity by an applied electric field, to cause a change in total reflected light, as light reflecting from the outer mirrors is in phase and light reflecting from the inner mirror is out of phase with light from the outer mirrors.

  3. Tandem betatron accelerator

    NASA Astrophysics Data System (ADS)

    Keinigs, Rhon K.

    1991-04-01

    1407_50The tandem betatron is a compact, high-current induction accelerator that has the capability to accelerate electrons to an energy of order one gigavolt. Based upon the operating principle of a conventional betatron, the tandem betatron employs two synchronized induction cores operating 180 degrees out of phase. Embedded within the cores are the vacuum chambers, and these are connected by linear transport sections to allow for moving the beam back and forth between the two betatrons. The 180 degree phase shift between the core fluxes permits the circumvention of the flux swing constraint that limits the maximum energy gain of a conventional betatron. By transporting the beam between the synchronized cores, an electron can access more than one acceleration cycle, and thereby continue to gain energy. This added degree of freedom also permits a significant decrease in the size of the magnet system. Biasing coils provide independent control of the confining magnetic field. Provided that efficient beam switching can be performed, it appears feasible that a one gigavolt electron beam can be generated and confined. At this energy, a high current electron beam circulating in a one meter radius orbit could provide a very intense source of short wavelength ((lambda) < 10 nm) synchrotron radiation. This has direct application to the emerging field of x-ray lithography. At more modest energies (10 MeV-30 MeV) a compact tandem betatron could be employed in the fields of medical radiation therapy, industrial radiography, and materials processing.

  4. Reisolation of Ehrlichia canis from blood and tissues of dogs after doxycycline treatment.

    PubMed Central

    Iqbal, Z; Rikihisa, Y

    1994-01-01

    We present evidence that supports the carrier status of dogs experimentally infected with Ehrlichia canis after treatment with doxycycline. Canine ehrlichiosis was induced in five dogs by intravenous inoculation with E. canis-infected DH82 cells. All animals developed mild clinical signs of transient fever, body weight loss, thrombocytopenia, and increased gamma globulin levels in plasma. An indirect fluorescent-antibody test (IFA) revealed that all dogs had seroconverted (titer, 5,120) by day 10 postinoculation (p.i.). E. canis was reisolated from blood samples collected at intervals throughout the 2-month period p.i. Doxycycline was administered orally once daily at 10 mg/kg of body weight per day for 1 week starting at 2 months p.i. Following treatment, gamma globulin levels in plasma were decreased. At necropsy on days 54 to 59 after the start of treatment, spleen, liver, kidney, and lymph nodes were collected for E. canis culture and histopathologic examination. Although the dogs did not show significant clinical signs during or after treatment with the antibiotic, E. canis was reisolated from the blood and tissue samples of three of five dogs. A 16-fold reduction in IFA titer was noted in two dogs which were negative for E. canis reisolation at day 49 after the start of treatment, whereas a zero- to fourfold reduction in IFA titer was seen in the remaining three dogs. Western immunoblot reactions to higher-molecular-size E. canis antigens in the sera of two dogs which were negative for E. canis on blood culture decreased, whereas they remained continuously high or only transiently decreased for the duration of the study for antigens in the sera of three dogs from which E. canis was reisolated. Histopathologically, prominent plasmacytosis in the kidney cortex was present in three dogs from which E. canis was reisolated, whereas the kidney cortices of two dogs had moderate to minor plasmacytosis. These findings pose questions regarding the efficacy, dosage and

  5. Detection of Rickettsia and Ehrlichia spp. in Ticks Associated with Exotic Reptiles and Amphibians Imported into Japan.

    PubMed

    Andoh, Masako; Sakata, Akiko; Takano, Ai; Kawabata, Hiroki; Fujita, Hiromi; Une, Yumi; Goka, Koichi; Kishimoto, Toshio; Ando, Shuji

    2015-01-01

    One of the major routes of transmission of rickettsial and ehrlichial diseases is via ticks that infest numerous host species, including humans. Besides mammals, reptiles and amphibians also carry ticks that may harbor Rickettsia and Ehrlichia strains that are pathogenic to humans. Furthermore, reptiles and amphibians are exempt from quarantine in Japan, thus facilitating the entry of parasites and pathogens to the country through import. Accordingly, in the current study, we examined the presence of Rickettsia and Ehrlichia spp. genes in ticks associated with reptiles and amphibians originating from outside Japan. Ninety-three ticks representing nine tick species (genera Amblyomma and Hyalomma) were isolated from at least 28 animals spanning 10 species and originating from 12 countries (Ghana, Jordan, Madagascar, Panama, Russia, Sri Lanka, Sudan, Suriname, Tanzania, Togo, Uzbekistan, and Zambia). None of the nine tick species are indigenous in Japan. The genes encoding the common rickettsial 17-kDa antigen, citrate synthase (gltA), and outer membrane protein A (ompA) were positively detected in 45.2% (42/93), 40.9% (38/93), and 23.7% (22/93) of the ticks, respectively, by polymerase chain reaction (PCR). The genes encoding ehrlichial heat shock protein (groEL) and major outer membrane protein (omp-1) were PCR-positive in 7.5% (7/93) and 2.2% (2/93) of the ticks, respectively. The p44 gene, which encodes the Anaplasma outer membrane protein, was not detected. Phylogenetic analysis showed that several of the rickettsial and ehrlichial sequences isolated in this study were highly similar to human pathogen genes, including agents not previously detected in Japan. These data demonstrate the global transportation of pathogenic Rickettsia and Ehrlichia through reptile- and amphibian-associated ticks. These imported animals have potential to transfer pathogens into human life. These results highlight the need to control the international transportation of known and

  6. Detection of Rickettsia and Ehrlichia spp. in Ticks Associated with Exotic Reptiles and Amphibians Imported into Japan

    PubMed Central

    Andoh, Masako; Sakata, Akiko; Takano, Ai; Kawabata, Hiroki; Fujita, Hiromi; Une, Yumi; Goka, Koichi; Kishimoto, Toshio; Ando, Shuji

    2015-01-01

    One of the major routes of transmission of rickettsial and ehrlichial diseases is via ticks that infest numerous host species, including humans. Besides mammals, reptiles and amphibians also carry ticks that may harbor Rickettsia and Ehrlichia strains that are pathogenic to humans. Furthermore, reptiles and amphibians are exempt from quarantine in Japan, thus facilitating the entry of parasites and pathogens to the country through import. Accordingly, in the current study, we examined the presence of Rickettsia and Ehrlichia spp. genes in ticks associated with reptiles and amphibians originating from outside Japan. Ninety-three ticks representing nine tick species (genera Amblyomma and Hyalomma) were isolated from at least 28 animals spanning 10 species and originating from 12 countries (Ghana, Jordan, Madagascar, Panama, Russia, Sri Lanka, Sudan, Suriname, Tanzania, Togo, Uzbekistan, and Zambia). None of the nine tick species are indigenous in Japan. The genes encoding the common rickettsial 17-kDa antigen, citrate synthase (gltA), and outer membrane protein A (ompA) were positively detected in 45.2% (42/93), 40.9% (38/93), and 23.7% (22/93) of the ticks, respectively, by polymerase chain reaction (PCR). The genes encoding ehrlichial heat shock protein (groEL) and major outer membrane protein (omp-1) were PCR-positive in 7.5% (7/93) and 2.2% (2/93) of the ticks, respectively. The p44 gene, which encodes the Anaplasma outer membrane protein, was not detected. Phylogenetic analysis showed that several of the rickettsial and ehrlichial sequences isolated in this study were highly similar to human pathogen genes, including agents not previously detected in Japan. These data demonstrate the global transportation of pathogenic Rickettsia and Ehrlichia through reptile- and amphibian-associated ticks. These imported animals have potential to transfer pathogens into human life. These results highlight the need to control the international transportation of known and

  7. Recombinant gp19 as a potential antigen for detecting anti-Ehrlichia canis antibodies in dog sera.

    PubMed

    Oliveira, Rômulo Silva de; Cunha, Rodrigo Casquero; Moraes-Filho, Jonas; Gonçales, Relber Aguiar; Lara, Ana Paula de Souza Stori de; Avila, Luciana Farias da Costa de; Labruna, Marcelo Bahia; Leite, Fábio Pereira Leivas

    2015-01-01

    The canine monocytic ehrlichiosis, caused by Ehrlichia canis, is endemic in several regions of Brazil. Some serological diagnostic techniques using immunodominant proteins of E. canis as antigens are available, but their specificities and sensitivities are questionable. Based on this, the objective of this study was to test the antigenic potential of the recombinant gp19 protein (rGP19) for subsequent use in diagnostic tests. The rGP19 expressed in the Escherichia coli strain BL21 (DE3) C41 was recognized in the sera from experimentally infected dogs using ELISA and Western blotting. Thus, it was possible to obtain a promising antigen with the ability to differentiate between E. canis-positive and -negative animals, even 1 week after infection. PMID:26291145

  8. Monolithic tandem solar cell

    DOEpatents

    Wanlass, M.W.

    1994-06-21

    A single-crystal, monolithic, tandem, photovoltaic solar cell is described which includes (a) an InP substrate having upper and lower surfaces, (b) a first photoactive subcell on the upper surface of the InP substrate, (c) a second photoactive subcell on the first subcell; and (d) an optically transparent prismatic cover layer over the second subcell. The first photoactive subcell is GaInAsP of defined composition. The second subcell is InP. The two subcells are lattice matched. 9 figs.

  9. Monolithic tandem solar cell

    DOEpatents

    Wanlass, Mark W.

    1991-01-01

    A single-crystal, monolithic, tandem, photovoltaic solar cell is described which includes (a) an InP substrate having upper and lower surfaces, (b) a first photoactive subcell on the upper surface of the InP substrate, and (c) a second photoactive subcell on the first subcell. The first photoactive subcell is GaInAsP of defined composition. The second subcell is InP. The two subcells are lattice matched. The solar cell can be provided as a two-terminal device or a three-terminal device.

  10. Bacterial Profiling Reveals Novel “Ca. Neoehrlichia”, Ehrlichia, and Anaplasma Species in Australian Human-Biting Ticks

    PubMed Central

    Gofton, Alexander W.; Doggett, Stephen; Ratchford, Andrew; Oskam, Charlotte L.; Paparini, Andrea; Ryan, Una; Irwin, Peter

    2015-01-01

    In Australia, a conclusive aetiology of Lyme disease-like illness in human patients remains elusive, despite growing numbers of people presenting with symptoms attributed to tick bites. In the present study, we surveyed the microbial communities harboured by human-biting ticks from across Australia to identify bacteria that may contribute to this syndrome. Universal PCR primers were used to amplify the V1-2 hyper-variable region of bacterial 16S rRNA genes in DNA samples from individual Ixodes holocyclus (n = 279), Amblyomma triguttatum (n = 167), Haemaphysalis bancrofti (n = 7), and H. longicornis (n = 7) ticks. The 16S amplicons were sequenced on the Illumina MiSeq platform and analysed in USEARCH, QIIME, and BLAST to assign genus and species-level taxonomies. Nested PCR and Sanger sequencing were used to confirm the NGS data and further analyse novel findings. All 460 ticks were negative for Borrelia spp. by both NGS and nested PCR analysis. Two novel “Candidatus Neoehrlichia” spp. were identified in 12.9% of I. holocyclus ticks. A novel Anaplasma sp. was identified in 1.8% of A. triguttatum ticks, and a novel Ehrlichia sp. was identified in both A. triguttatum (1.2%) ticks and a single I. holocyclus (0.6%) tick. Further phylogenetic analysis of novel “Ca. Neoehrlichia”, Anaplasma and Ehrlichia based on 1,265 bp 16S rRNA gene sequences suggests that these are new species. Determining whether these newly discovered organisms cause disease in humans and animals, like closely related bacteria do abroad, is of public health importance and requires further investigation. PMID:26709826

  11. Development of a mitochondrial 12S rDNA analysis for distinguishing Sciuridae species with potential to transmit Ehrlichia and Borrelia species to feeding Amblyomma americanum (Acari: Ixodidae).

    PubMed

    Goessling, Lisa S; Allan, Brian F; Mandelbaum, Rachel S; Thach, Robert E

    2012-05-01

    Unique oligonucleotide probes were synthesized to distinguish among closely related vertebrate mitochondrial rDNA sequences present in residual bloodmeals in emergent Amblyomma americanum (L.) (Acari: Ixodidae) nymph life-stage ticks. Use of these probes enabled the identification of the Eastern gray squirrel as an important bloodmeal source in nymphs harboring Ehrlichia and Borrelia species. These results were confirmed by identifying these same bacterial genera in Eastern gray squirrel tissues. PMID:22679888

  12. Fueling of tandem mirror reactors

    SciTech Connect

    Gorker, G.E.; Logan, B.G.

    1985-01-01

    This paper summarizes the fueling requirements for experimental and demonstration tandem mirror reactors (TMRs), reviews the status of conventional pellet injectors, and identifies some candidate accelerators that may be needed for fueling tandem mirror reactors. Characteristics and limitations of three types of accelerators are described; neutral beam injectors, electromagnetic rail guns, and laser beam drivers. Based on these characteristics and limitations, a computer module was developed for the Tandem Mirror Reactor Systems Code (TMRSC) to select the pellet injector/accelerator combination which most nearly satisfies the fueling requirements for a given machine design.

  13. 47 CFR 69.111 - Tandem-switched transport and tandem charge.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 3 2014-10-01 2014-10-01 false Tandem-switched transport and tandem charge. 69... SERVICES (CONTINUED) ACCESS CHARGES Computation of Charges § 69.111 Tandem-switched transport and tandem...-switched transport shall consist of two rate elements, a transmission charge and a tandem switching...

  14. 47 CFR 69.111 - Tandem-switched transport and tandem charge.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false Tandem-switched transport and tandem charge. 69... SERVICES (CONTINUED) ACCESS CHARGES Computation of Charges § 69.111 Tandem-switched transport and tandem...-switched transport shall consist of two rate elements, a transmission charge and a tandem switching...

  15. Sequence alignment with tandem duplication

    SciTech Connect

    Benson, G.

    1997-12-01

    Algorithm development for comparing and aligning biological sequences has, until recently, been based on the SI model of mutational events which assumes that modification of sequences proceeds through any of the operations of substitution, insertion or deletion (the latter two collectively termed indels). While this model has worked farily well, it has long been apparent that other mutational events occur. In this paper, we introduce a new model, the DSI model which includes another common mutational event, tandem duplication. Tandem duplication produces tandem repeats which are common in DNA, making up perhaps 10% of the human genome. They are responsible for some human diseases and may serve a multitude of functions in DNA regulation and evolution. Using the DSI model, we develop new exact and heuristic algorithms for comparing and aligning DNA sequences when they contain tandem repeats. 30 refs., 3 figs.

  16. Isolation, in vitro propagation, genetic analysis, and immunogenic characterization of an Ehrlichia canis strain from southeastern Brazil

    PubMed Central

    Rieck, Susana Elisa; Ueira-Vieira, Carlos; Labruna, Marcelo Bahia; Beletti, Marcelo Emílio

    2014-01-01

    Amplification of the 16S rRNA gene from a blood sample obtained from a dog in southeastern Brazil was used to confirm a naturally acquired Ehrlichia (E.) canis infection. Following isolation and culturing of the new bacterial strain called Uberlândia, partial sequences of the dsb and p28 genes were obtained. The dsb partial sequence of the novel strain was 100% similar to dsb gene sequences of E. canis obtained from different geographic areas around the world. Conversely, the p28 partial sequence for the E. canis Uberlândia strain differed at several nucleotides from other sequences available in GenBank. To confirm the antigenic profile of the Uberlândia strain, an indirect immunofluorescence assay against E. canis antigens was performed using dog sera collected from two different areas in Brazil (Uberlândia and São Paulo). The results suggest that both antigens were able to identify animals seropositive for E. canis in Brazil since these Brazilian strains appear to be highly conserved. PMID:24136211

  17. Molecular detection of Ehrlichia canis, Hepatozoon canis and Babesia canis vogeli in stray dogs in Mahasarakham province, Thailand.

    PubMed

    Piratae, Supawadee; Pimpjong, Kiattisak; Vaisusuk, Kotchaphon; Chatan, Wasupon

    2015-01-01

    Canine tick borne diseases showing distribution worldwide have caused morbidity and mortality in dogs. This study observed the mainly tick borne pathogens described for dogs in Thailand, Ehrlichia canis, Hepatozoon canis and Babesia canis vogeli. From May to July 2014, blood samples were collected from 79 stray dogs from 7 districts of Mahasarakham province to molecular surveyed for 16s rRNA gene of E. canis and 18s rRNA gene of H. canis and B. canis vogeli. Twenty eight (35.44%) of stray dogs showed the infection with tick borne pathogens. The prevalence of E. canis infection was the highest with 21.5% (17/79). DNA of H. canis and B. canis vogeli were detected at the prevalence of 10.1% (8/79) and 6.3% (5/79), respectively. Co-infection between E. canis and B. canis vogeli were identified in 2 (2.5%) dogs. The results indicated that a wide range of tick borne pathogens are circulation in the canine population in Mahasarakham province. This study is the first report on prevalence of E. canis, H. canis and B. canis vogeli in stray dogs in Mahasarakham, a province in northern part of Thailand. This data providing is important to understand the prevalence of E. canis, H. canis and B. canis vogeli infection in stray dogs in this region, which will assist in the management of these blood parasite. PMID:26568991

  18. Seroprevalence and Risk Factors of Ehrlichia canis Infection among Companion Dogs of Mashhad, North East of Iran, 2009–2010

    PubMed Central

    Ansari-Mood, Maneli; Khoshnegah, Javad; Mohri, Mehrdad; Rajaei, Seyed Mehdi

    2015-01-01

    Background: The aims of this study were to determine the seroprevalence of canine ehrlichiosis and risk factors of this disease in companion dogs’ population of Mashhad, North East of Iran. Canine Monocytic Ehrlichiosis (CME) is a zoonotic disease transmitted by ticks, Rhipicephalus sanguineus, and caused by an obligate intracellular bacterium, Ehrlichia canis. Methods: During September 2009 until November 2010, 250 companion dogs from Mashhad, North-East of Iran, were examined for serum antibody detection against E. canis by means of immunofluorescence assay test (IFAT) and factors associated with a positive antibody response. Results: There was a very low prevalence of anti-E. canis antibodies (0.8%, 2/250) among studied dogs. The antibody titers for two seropositive dogs were 1:80 and 1:160, respectively. One (0.4%) of seropositive dogs was infested with, R. sanguineus. In blood smears from one of infested dogs (0.4%), typical morulae of E. canis was observed in lymphocytes. The results confirm that the lowest occurrence of reactive dogs indoors probably related to low tick infestion. Conclusion: This is the first report that describes serological evidences of canine monocytic ehrlichiosis in North-East of Iran. Results suggested that E. canis infection in owned pet dogs from North of Khorasan was not endemic from 2009 to 2010. Additional molecular studies are necessary to confirm E. canis infection and to identify the local strains of the organism. PMID:26623430

  19. Detection of Neorickettsia (Ehrlichia) risticii in tissues of mice experimentally infected with cercariae of trematodes by in situ hybridization.

    PubMed

    Chae, Joon-seok; Kim, Min-seok; Madigan, John

    2002-09-01

    Neorickettsia (Ehrlichia) risticii was demonstrated to occur in cercariae developing in Juga yrekaensis snails by experimental transmission, genetic detection and histopathology. Cercariae were isolated from the digestive glands of snails collected in a fresh stream water area of Siskiyou County, CA, and inoculated into CF1 mice. Mice developed clinical signs, splenomegaly and histopathologic abnormalities. The agent was maintained by serial passages of whole blood in CF1 mice. A 527-bp product of the 16S rRNA gene of N. risticii was serially detected by nested PCR in blood, feces, salivary gland, suprarenal gland, spleen, intestine and bone marrow of inoculated mice. N. risticii DNA was detected by in situ hybridization with DIG-labeled probe in PCR-positive salivary gland, intestine and spleen tissue sections of experimental mice on day 30 after inoculation. Infection in mice was established when cercariae were inoculated by either IP or SC routes but not established following intraoral route. N. risticii was detected by PCR in spleen, intestine and bone marrow even after 73 days post-inoculation whereas blood from the same animals became negative at 58 days. N. risticii was observed by in situ hybridization in salivary gland, spleen and intestine of mice infected by IP or SC inoculation. This ISH protocol should aid investigations on the host range of the Neorickettsiosis and pathogenesis of neorickettiosis in vector, animal or human. PMID:12151198

  20. Tandem Cylinder Noise Predictions

    NASA Technical Reports Server (NTRS)

    Lockhard, David P.; Khorrami, Mehdi R.; CHoudhari, Meelan M.; Hutcheson, Florence V.; Brooks, Thomas F.; Stead, Daniel J.

    2007-01-01

    In an effort to better understand landing-gear noise sources, we have been examining a simplified configuration that still maintains some of the salient features of landing-gear flow fields. In particular, tandem cylinders have been studied because they model a variety of component level interactions. The present effort is directed at the case of two identical cylinders spatially separated in the streamwise direction by 3.7 diameters. Experimental measurements from the Basic Aerodynamic Research Tunnel (BART) and Quiet Flow Facility (QFF) at NASA Langley Research Center (LaRC) have provided steady surface pressures, detailed off-surface measurements of the flow field using Particle Image Velocimetry (PIV), hot-wire measurements in the wake of the rear cylinder, unsteady surface pressure data, and the radiated noise. The experiments were conducted at a Reynolds number of 166 105 based on the cylinder diameter. A trip was used on the upstream cylinder to insure a fully turbulent shedding process and simulate the effects of a high Reynolds number flow. The parallel computational effort uses the three-dimensional Navier-Stokes solver CFL3D with a hybrid, zonal turbulence model that turns off the turbulence production term everywhere except in a narrow ring surrounding solid surfaces. The current calculations further explore the influence of the grid resolution and spanwise extent on the flow and associated radiated noise. Extensive comparisons with the experimental data are used to assess the ability of the computations to simulate the details of the flow. The results show that the pressure fluctuations on the upstream cylinder, caused by vortex shedding, are smaller than those generated on the downstream cylinder by wake interaction. Consequently, the downstream cylinder dominates the noise radiation, producing an overall directivity pattern that is similar to that of an isolated cylinder. Only calculations based on the full length of the model span were able to

  1. Serological and molecular investigation of Ehrlichia spp. and Anaplasma spp. in ticks and blood of dogs, in the Thrace Region of Turkey.

    PubMed

    Çetinkaya, Handan; Matur, Erdal; Akyazi, İbrahim; Ekiz, Elif Ergul; Aydin, Levent; Toparlak, Mufit

    2016-07-01

    In recent years, tick-borne diseases like ehrlichiosis and anaplasmosis became widespread worldwide threatening the health of both human and companion animals. Therefore, the aim of this study was to determine the presence of Anaplasma spp., and Ehrlichia spp. in dogs and ticks in the Thrace Region of Turkey. A total of 400 blood samples and 912 ticks were collected from dogs living in shelters that are located in four cities (Istanbul, Edirne, Tekirdag and Kirklareli) of the Thrace Region. Blood and buffy coat smears were prepared for microscopic examination. Hematologic and serologic analyses were performed using cell counter and commercial Snap3Dx test kit, respectively. Eight hundred fifty of collected ticks were classified as Rhipicephalus sanguineus, 33 as Rhipicephalus turanicus and 29 as Ixodes ricinus. After DNA extraction from blood samples and pooled ticks (127 tick pools, in total), nested PCR was performed to detect the DNA of Anaplasma spp., and Ehrlichia spp. The seroprevalence of Ehrlichia canis was 27.25% (109) by Snap3Dx test and the total molecular positivity was 11.75% (47) in dog blood samples and 21.25% (27) in tick pools by nested PCR. The frequencies of the infected blood samples with E. canis, Anaplasma phagocytophilum and Anaplasma platys were detected as 6%, 4% and 6%, respectively. E. canis and A. platys were detected in R. sanguineus pools with a ratio of 15.75% and 0.7%, respectively. In addition, A. platys was also detected in R. turanicus pools (0.7%). A. phagocytophilum was found only in I. ricinus pools (3.93%). Morulae of three species were detected in buffy coat and blood smears. While anemia was observed in dogs infected with E. canis and co-infected (with one or more species), thrombocytopenia was observed only in co-infected dogs. This is the first study providing evidence for the presence of Anaplasma spp. and Ehrlichia spp. in dogs and ticks in the Thrace Region of Turkey. Based on the results of the tests used in this study

  2. Molecular analysis of the rRNA genes of Babesia spp and Ehrlichia canis detected in dogs from RibeirÃo Preto, Brazil

    PubMed Central

    Oliveira, L.P.; Cardozo, G.P.; Santos, E.V.; Mansur, M.A.B.; Donini, I.A.N.; Zissou, V.G.; Roberto, P.G.; Marins, M.

    2009-01-01

    The partial DNA sequences of the 18S rRNA gene of Babesia canis and the 16S rRNA gene of Ehrlichia canis detected in dogs from Ribeirão Preto, Brazil, were compared to sequences from other strains deposited in GenBank. The E. canis strain circulating in Ribeirão Preto is identical to other strains previously detected in the region, whereas the subspecies Babesia canis vogeli is the main Babesia strain circulating in dogs from Ribeirão Preto. PMID:24031351

  3. Detection of Ehrlichia canis, Babesia vogeli, and Toxoplasma gondii DNA in the Brain of Dogs Naturally Infected with Leishmania infantum.

    PubMed

    Cardinot, Cinthya B; Silva, José E S; Yamatogi, Ricardo S; Nunes, Cáris M; Biondo, Alexander W; Vieira, Rafael F C; Junior, João P Araujo; Marcondes, Mary

    2016-04-01

    The aims of this study were to investigate the presence of Leishmania infantum and possible co-infection with Anaplasma platys , Babesia vogeli, Ehrlichia canis , and Toxoplasma gondii in the brain of 24 dogs naturally infected by L. infantum . A total of 24 mongrel adult dogs (22 clinically affected, 2 with neurological signs, and 2 subclinically infected) aged between 2 and 5 yr, naturally infected by visceral leishmaniasis, were selected. Fragments from meninges, frontal cortex, thalamus, cerebellum, and choroid plexus of the lateral ventricles and fourth ventricle were collected, mixed, and tested by real-time polymerase chain reaction (qPCR). Leishmania infantum DNA was detected in 95.8% (23/24) of the infected dogs, including the subclinically infected. A total of 14/24 (58.3%) dogs were co-infected by E. canis and L. infantum , 4/24 (16.7%) were co-infected by E. canis , B. vogeli, and L. infantum , 2/24 (8.3%) were co-infected by B. vogeli and L. infantum , and 1/24 (4.2%) dog was co-infected by E. canis , B. vogeli, T. gondii , and L. infantum . All 24 brain samples tested negative for A. platys . These results demonstrate that L. infantum is able to penetrate into the brain parenchyma, either alone or in association to other zoonotic pathogens. In addition, qPCR could be considered for adequate evaluation of Leishmania in the brain tissue of dogs with neurological signs that have died. PMID:26765523

  4. Ectoparasite Infestations and Canine Infection by Rickettsiae and Ehrlichiae in a Semi-Arid Region of Northeastern Brazil.

    PubMed

    Araes-Santos, Ana Isabel; Moraes-Filho, Jonas; Peixoto, Renata M; Spolidorio, Mariana G; Azevedo, Sérgio S; Costa, Mateus M; Labruna, Marcelo B; Horta, Mauricio C

    2015-11-01

    This study investigated the prevalence of Rickettsia spp. and Ehrlichia canis infection in dogs and their ectoparasites from rural and urban areas of two municipalities, Petrolina and Juazeiro, within a semiarid region (Caatinga biome) of northeastern Brazil, by immunofluorescence assay (IFA) and polymerase chain reaction (PCR). Overall, 12.1% (61/504) and 23.0% (116/504) of canine plasma samples had antibodies reactive to Rickettsia spp. and E. canis. E. canis DNA was detected by PCR in 8.3% (42/504) of canine blood samples, whereas no blood sample was positive for Rickettsia spp. The infection by E. canis was determined by PCR in 4.9% (14/285) Rhipicephalus sanguineus sensu lato (s.l.) ticks and by Rickettsia felis in 1.1% (3/285) and 40.6% (74/182) ticks and fleas, respectively. Multivariate regression analyses revealed that canine seropositivity to Rickettsia spp. was associated statistically with the variables "to reside in Petrolina" and "presence of ectoparasites." Our results indicate that canine infection by E. canis might be endemic in the Caatinga biome as it is in other Brazilian biomes. Although no previous serosurvey for Rickettsia spp. has been conducted on dogs from the Caatinga biome, our values are much lower than the ones reported for rural dogs from other Brazilian biomes. These differences are likely related to the semiarid climate of the aatinga biome, which minimizes the exposure of rural dogs to Amblyomma spp. ticks, the most common vectors of Rickettsia spp. in Brazil. Considering that dogs are excellent sentinels for human exposure to Rickettsia spp., we can infer that the risks of human acquiring tick-borne rickettsiosis in the Caatinga region of the present study are low. The rickettsial infection rates in fleas and ticks were not related to canine seropositivity; i.e., areas with higher Rickettsia infection rates in fleas had the lowest canine seroreactivity to Rickettsia spp. PMID:26565771

  5. Infection with Ehrlichia canis and Anaplasma platys (Rickettsiales: Anaplasmataceae) in two lineages of Rhipicephalus sanguineus sensu lato (Acari: Ixodidae) from Argentina.

    PubMed

    Cicuttin, Gabriel L; Tarragona, Evelina L; De Salvo, M Nazarena; Mangold, Atilio J; Nava, Santiago

    2015-09-01

    Natural infection with Ehrlichia canis and Anaplasma platys in ticks belonging to the tropical and temperate lineages of Rhipicephalus sanguineus sensu lato from Argentina was evaluated. Samples were tested for Ehrlichia canis infection by PCR assays using 16S rRNA, dsb and p28 gene, while detection of A. platys was performed with 16S rRNA and groESL gene. The assignment of the ticks to each lineage was corroborated with 16S rDNA sequences. All ticks infected with E. canis and A. platys belonged to the tropical lineage. These results constitute the first record of E. canis infection in R. sanguineus s.l ticks from Argentina. No ticks from the temperate lineage were found to be infected with E. canis, coinciding with previous studies performed in Argentina and Uruguay where E. canis infection was not detected in R. sanguineus s.l from the temperate lineage. Because the presence of the tropical lineage of R. sanguineus s.l has been documented in tropical areas of northern Argentina between 22° and 24° of south latitude, the findings of this work indicate that transmission of E. canis and A. platys to dogs by R. sanguineus s.l probably occurs along this region. PMID:26100492

  6. Effects of doxycycline on haematology, blood chemistry and peripheral blood lymphocyte subsets of healthy dogs and dogs naturally infected with Ehrlichia canis.

    PubMed

    Villaescusa, A; García-Sancho, M; Rodríguez-Franco, F; Tesouro, M Á; Sainz, Á

    2015-06-01

    Canine monocytic ehrlichiosis (CME), caused by Ehrlichia canis, is a vector-borne disease with a worldwide distribution. It has been proposed that the pathogenesis, clinical severity and outcome of disease caused by Ehrlichia spp. can be attributed to the immune response rather than to any direct rickettsial effect. Moreover, doxycycline, the antimicrobial of choice for the treatment of CME, has immunomodulatory and anti-inflammatory properties associated with blood leukocyte proliferation function, cytokine synthesis, and matrix metalloproteinase activity. In order to assess the potential effects of doxycycline, dependent and independent of its antimicrobial activity, the present study compared changes in haematology, blood chemistry and circulating lymphocyte subpopulations in 12 healthy dogs and 20 dogs with CME after doxycycline therapy. Some changes were recorded only in the CME affected dogs, probably due to the antimicrobial effect of doxycycline. However, increases in mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration, platelet count and α2-globulins, and decreased plasma creatinine were observed in both healthy and CME affected dogs. The absolute count of B lymphocytes (CD21(+)) increased initially, but then decreased until the end of the study period in both groups. A potential effect of doxycycline unrelated to its antimicrobial activity against E. canis is suggested, taking into account the results observed both in healthy dogs and in dogs with CME. PMID:25957920

  7. A real-time PCR assay for detection of the Ehrlichia muris-like agent, a newly recognized pathogen of humans in the upper Midwestern United States

    PubMed Central

    Allerdice, Michelle E.J.; Pritt, Bobbi S.; Sloan, Lynne M.; Paddock, Christopher D.; Karpathy, Sandor E.

    2015-01-01

    The Ehrlichia muris-like agent (EMLA) is an emerging, tick-transmitted human pathogen that occurs in the upper Midwestern United States. Here, we describe the development and validation of a p13-based quantitative real-time PCR TaqMan assay to detect EMLA in blood or tissues of ticks, humans, and rodents. The primer and probe specificities of the assay were ascertained using a large panel of various Ehrlichia species and other members of Rickettsiales. In addition to control DNA, both non-infected and EMLA-infected human blood, Mus musculus blood, and Mus musculus tissue extracts were evaluated, as were non-infected and EMLA-infected I. scapularis and uninfected D. variabilis DNA lysates. The specificity of the probe was determined via real-time PCR. An EMLA p13 control plasmid was constructed, and serial dilutions were used to determine the analytical sensitivity, which was found to be 1 copy per 4 μl of template DNA. The sensitivity and specificity of this assay provides a powerful tool for ecological studies involving arthropod vectors and their mammalian hosts. PMID:26507653

  8. Nanocrystal assembly for tandem catalysis

    DOEpatents

    Yang, Peidong; Somorjai, Gabor; Yamada, Yusuke; Tsung, Chia-Kuang; Huang, Wenyu

    2014-10-14

    The present invention provides a nanocrystal tandem catalyst comprising at least two metal-metal oxide interfaces for the catalysis of sequential reactions. One embodiment utilizes a nanocrystal bilayer structure formed by assembling sub-10 nm platinum and cerium oxide nanocube monolayers on a silica substrate. The two distinct metal-metal oxide interfaces, CeO.sub.2--Pt and Pt--SiO.sub.2, can be used to catalyze two distinct sequential reactions. The CeO.sub.2--Pt interface catalyzed methanol decomposition to produce CO and H.sub.2, which were then subsequently used for ethylene hydroformylation catalyzed by the nearby Pt--SiO.sub.2 interface. Consequently, propanal was selectively produced on this nanocrystal bilayer tandem catalyst.

  9. "Nanocrystal bilayer for tandem catalysis"

    SciTech Connect

    Yamada, Yusuke; Tsung, Chia Kuang; Huang, Wenyu; Huo, Ziyang; E.Habas, Susan E; Soejima, Tetsuro; Aliaga, Cesar E; Samorjai, Gabor A; Yang, Peidong

    2011-01-24

    Supported catalysts are widely used in industry and can be optimized by tuning the composition and interface of the metal nanoparticles and oxide supports. Rational design of metal-metal oxide interfaces in nanostructured catalysts is critical to achieve better reaction activities and selectivities. We introduce here a new class of nanocrystal tandem catalysts that have multiple metal-metal oxide interfaces for the catalysis of sequential reactions. We utilized a nanocrystal bilayer structure formed by assembling platinum and cerium oxide nanocube monolayers of less than 10 nm on a silica substrate. The two distinct metal-metal oxide interfaces, CeO2-Pt and Pt-SiO2, can be used to catalyse two distinct sequential reactions. The CeO2-Pt interface catalysed methanol decomposition to produce CO and H2, which were subsequently used for ethylene hydroformylation catalysed by the nearby Pt-SiO2 interface. Consequently, propanal was produced selectively from methanol and ethylene on the nanocrystal bilayer tandem catalyst. This new concept of nanocrystal tandem catalysis represents a powerful approach towards designing high-performance, multifunctional nanostructured catalysts

  10. Retrospective analyses of dogs found serologically positive for Ehrlichia canis in Cebu, Philippines from 2003 to 2014

    PubMed Central

    Ybañez, Adrian P.; Ybañez, Rochelle Haidee D.; Villavelez, Rex R.; Malingin, Honey Pearl F.; Barrameda, Dana Natasha M.; Naquila, Sharmaine V.; Olimpos, Shiella Mae B.

    2016-01-01

    Aim: The study aimed to document the clinical and hematological observations of dogs found serologically positive for Ehrlichia canis and to identify parameters or factors that are associated with the disease with focus on the anemic and thrombocytopenic state of the infected dogs. Materials and Methods: From 7 participating veterinary establishments, a total of 913 cases from 2003 to 2014 were initially assessed using inclusion criteria, including E. canis diagnosis by the attending veterinarian and the presence of ticks or history of infestation, thrombocytopenia, and/or anemia. From these, 438 cases that were found serologically positive for E. canis using commercial test kits were selected. Profile, clinical observations and hematological test results were obtained from the selected cases. Computations for statistical associations between the anemic and thrombocytopenic state of the infected dogs and their profile, observed clinical signs and other hematological values were performed. Results: Most of the dogs were purebred (60.0%) and female (51.1%) and were within the age range of 1-5 years (38.4%). The mean packed cell volume (PCV), red blood cell (RBC) count, and platelet count were lower than the normal values while the absolute count of basophils were higher than normal values. Creatinine and blood urea nitrogen (BUN) appear to be elevated. The most common clinical signs observed were inappetence (41.3%), lethargy/depression (35.6%), vomiting (32.4%), fever (18.5%), paleness (8.2%), and epistaxis (6.6%). Analyses showed that there were no significant differences on the hematological values and clinical signs between thrombocytopenic and non-thrombocytopenic seropositive dogs. Moreover, very weak correlations between platelet count and RBC count, absolute lymphocyte count, and neutrophil count were found. On the other hand, only paleness (p=0.008) and epistaxis (p=0.004) were found to be significantly different between anemic and non-anemic patients. This

  11. Amblyomma variegatum in cattle in Marie Galante, French Antilles: prevalence, control measures, and infection by Ehrlichia ruminantium.

    PubMed

    Molia, Sophie; Frebling, Mathieu; Vachiéry, Nathalie; Pinarello, Valérie; Petitclerc, Martial; Rousteau, Alain; Martinez, Dominique; Lefrançois, Thierry

    2008-05-31

    We report Marie Galante as one of the Caribbean islands most heavily infested by the tropical bont tick (TBT) Amblyomma variegatum which is associated with two major diseases of ruminants: heartwater and dermatophilosis. In 2005, a survey was undertaken to assess the prevalence of TBT infestation in cattle, the prevalence of Ehrlichia ruminantium infection in TBTs, and the tick control measures implemented by livestock owners. A random sample of 195 cattle herds out of 1885 recorded on the island was investigated by thoroughly counting adult ticks on each animal and filling a questionnaire. A randomly collected sample of 136 TBTs was tested for infection by E. ruminantium by pCS20 nested PCR. Cattle herd prevalence (hp) was 73.8% for infestation by at least one TBT, 17.9% for infestation by at least one engorged female TBT, and 8.2% for clinical dermatophilosis. Cattle individual prevalence was 42.3% for infestation by at least one TBT, 6.6% for infestation by at least one engorged female TBT, and 2.2% for clinical dermatophilosis. The minimum, maximum and average numbers of TBTs per infested animal were, respectively 1, 108 and 11.5. Prevalence of TBT infection by E. ruminantium was 19.1%. No significant difference in herd prevalence was found among parishes or among ecological zones. For cattle owners treating against ticks (97.9% of all owners), all used aspersion of amitraz and herd prevalence was significantly different among those treating every 1-2-week (hp=69.6%, n=148), and less often than every 2-week (hp=88.6%, n=35) (P=0.031). Of the 42 herd subunits treated less than 4 days before the survey, 27 (64%) were infested with at least one TBT, and 6 (14%) with at least one engorged female TBT. These results indicate a high level of TBT infestation in Marie Galante, the inefficacy of tick treatments currently performed, and the need for an improved tick control strategy. Persisting high levels of infestation in Marie Galante threaten the success of on

  12. In vitro culture and structural differences in the major immunoreactive protein gp36 of geographically distant Ehrlichia canis isolates.

    PubMed

    Zweygarth, Erich; Cabezas-Cruz, Alejandro; Josemans, Antoinette I; Oosthuizen, Marinda C; Matjila, Paul T; Lis, Katarzyna; Broniszewska, Marzena; Schöl, Heidrun; Ferrolho, Joana; Grubhoffer, Libor; Passos, Lygia M F

    2014-06-01

    Ehrlichia canis, the etiologic agent of canine ehrlichiosis, is an obligate intracytoplasmic Gram-negative tick-borne bacterium belonging to the Anaplasmataceae family. E. canis is distributed worldwide and can cause serious and fatal infections in dogs. Among strains of E. canis, the 16S rRNA gene DNA sequences are highly conserved. Using this gene to genetically differentiate isolates is therefore difficult. As an alternative, the gene gp36, which encodes for a major immunoreactive protein in E. canis, has been successfully used to characterize the genetic diversity of this pathogen. The present study describes the isolation and continuous propagation of a Spanish and 2 South African isolates of E. canis in IDE8 tick cells. Subsequently, canine DH82 cell cultures were infected using initial bodies obtained from infected IDE8 cultures. It was possible to mimic the life cycle of E. canis in vitro by transferring infection from tick cells to canine cells and back again. To characterize these E. canis strains at the molecular level, the 16S rRNA and gp36 genes were amplified by PCR, sequenced, and aligned with corresponding sequences available in GenBank. All 16S rRNA sequences amplified in this study were identical to previously reported E. canis strains. Maximum likelihood analysis based on the gp36 amino acid sequences showed that the South African and Spanish strains fall into 2 well-defined phylogenetic clusters amongst other E. canis strains. The members of these 2 phylogenetic clusters shared 2 unique molecular properties in the gp36 amino acid sequences: (i) deletion of glycine 117 and (ii) the presence of an additional putative N-linked glycosylation site. We further show correlation between the putative secondary structure and the theoretical isoelectric point (pI) of the gp36 amino acid sequences. A putative role of gp36 as an adhesin in E. canis is discussed. Overall, we report the successful in vitro culture of 3 new E. canis strains which present

  13. Development of Structure-Based Vaccines for Ehrlichiosis.

    PubMed

    Thomas, Sunil

    2016-01-01

    The obligate intracellular bacterium Ehrlichia chaffeensis that resides in mononuclear phagocytes is the etiologic agent of human monocytotropic ehrlichiosis (HME). HME is an emerging and often life-threatening zoonotic, tick-transmitted infectious disease in the USA. Lack of early diagnosis and treatment of HME are the main factors that lead to severe and fatal disease. Ehrlichia also causes diseases in companion animals and domesticated ruminants. E. chaffeensis and E. canis cause canine ehrlichioses in dogs, whereas E. ruminantium causes heartwater in cattle, sheep, and goats. As yet there are no commercially available vaccines to protect against these pathogens. This chapter describes a protocol to develop a structure-based vaccine for Ehrlichia based on the antigenic proteins P28-19 and Ehrlichia Hsp60. PMID:27076151

  14. Short Tandem Repeat DNA Internet Database

    National Institute of Standards and Technology Data Gateway

    SRD 130 Short Tandem Repeat DNA Internet Database (Web, free access)   Short Tandem Repeat DNA Internet Database is intended to benefit research and application of short tandem repeat DNA markers for human identity testing. Facts and sequence information on each STR system, population data, commonly used multiplex STR systems, PCR primers and conditions, and a review of various technologies for analysis of STR alleles have been included.

  15. Detecting long tandem duplications in genomic sequences

    PubMed Central

    2012-01-01

    Background Detecting duplication segments within completely sequenced genomes provides valuable information to address genome evolution and in particular the important question of the emergence of novel functions. The usual approach to gene duplication detection, based on all-pairs protein gene comparisons, provides only a restricted view of duplication. Results In this paper, we introduce ReD Tandem, a software using a flow based chaining algorithm targeted at detecting tandem duplication arrays of moderate to longer length regions, with possibly locally weak similarities, directly at the DNA level. On the A. thaliana genome, using a reference set of tandem duplicated genes built using TAIR,a we show that ReD Tandem is able to predict a large fraction of recently duplicated genes (dS < 1) and that it is also able to predict tandem duplications involving non coding elements such as pseudo-genes or RNA genes. Conclusions ReD Tandem allows to identify large tandem duplications without any annotation, leading to agnostic identification of tandem duplications. This approach nicely complements the usual protein gene based which ignores duplications involving non coding regions. It is however inherently restricted to relatively recent duplications. By recovering otherwise ignored events, ReD Tandem gives a more comprehensive view of existing evolutionary processes and may also allow to improve existing annotations. PMID:22568762

  16. The characterization of tandem and corrugated wings

    NASA Astrophysics Data System (ADS)

    Lian, Yongsheng; Broering, Timothy; Hord, Kyle; Prater, Russell

    2014-02-01

    Dragonfly wings have two distinct features: a tandem configuration and wing corrugation. Both features have been extensively studied with the aim to understand the superior flight performance of dragonflies. In this paper we review recent development of tandem and corrugated wing aerodynamics. With regards to the tandem configuration, this review will focus on wing/wing and wing/vortex interactions at different flapping modes and wing spacing. In addition, the aerodynamics of tandem wings under gusty conditions will be reviewed and compared with isolated wings to demonstrate the gust resistance characteristics of flapping wings. Regarding corrugated wings, we review their structural and aerodynamic characteristics.

  17. Recent Activities at Tokai Tandem Accelerator

    SciTech Connect

    Ishii, Tetsuro

    2010-05-12

    Recent activities at the JAEA-Tokai tandem accelerator facility are presented. The terminal voltage of the tandem accelerator reached 19.1 MV by replacing acceleration tubes. The multi-charged positive-ion injector was installed in the terminal of the tandem accelerator, supplying high-current noble-gas ions. A superconducting cavity for low-velocity ions was developed. Radioactive nuclear beams of {sup 8,9}Li and fission products, produced by the tandem accelerator and separated by the ISOL, were supplied with experiment. Recent results of nuclear physics experiments are reported.

  18. Tandem mirror technology demonstration facility

    SciTech Connect

    Not Available

    1983-10-01

    This report describes a facility for generating engineering data on the nuclear technologies needed to build an engineering test reactor (ETR). The facility, based on a tandem mirror operating in the Kelley mode, could be used to produce a high neutron flux (1.4 MW/M/sup 2/) on an 8-m/sup 2/ test area for testing fusion blankets. Runs of more than 100 h, with an average availability of 30%, would produce a fluence of 5 mW/yr/m/sup 2/ and give the necessary experience for successful operation of an ETR.

  19. Improved monolithic tandem solar cell

    SciTech Connect

    Wanlass, M.W.

    1991-04-23

    A single-crystal, monolithic, tandem, photovoltaic solar cell is described which includes (a) an InP substrate having upper and lower surfaces, (b) a first photoactive subcell on the upper surf ace of the InP substrate, (c) a second photoactive subcell on the first subcell; and (d) an optically transparent prismatic cover layer over the second subcell. The first photoactive subcell is GaInAsP of defined composition. The second subcell is InP. The two subcells are lattice matched.

  20. Growth of Ehrlichia canis, the causative agent of canine monocytic ehrlichiosis, in vector and non-vector ixodid tick cell lines.

    PubMed

    Ferrolho, Joana; Simpson, Jennifer; Hawes, Philippa; Zweygarth, Erich; Bell-Sakyi, Lesley

    2016-06-01

    Canine monocytic ehrlichiosis is caused by Ehrlichia canis, a small gram-negative coccoid bacterium that infects circulating monocytes. The disease is transmitted by the brown dog tick Rhipicephalus sanguineus s.l. and is acknowledged as an important infectious disease of dogs and other members of the family Canidae worldwide. E. canis is routinely cultured in vitro in the canine monocyte-macrophage cell line DH82 and in non-vector Ixodes scapularis tick cell lines, but not in cells derived from its natural vector. Here we report infection and limited propagation of E. canis in the tick cell line RSE8 derived from the vector R. sanguineus s.l., and successful propagation through six passages in a cell line derived from the experimental vector Dermacentor variabilis. In addition, using bacteria semi-purified from I. scapularis cells we attempted to infect a panel of cell lines derived from non-vector species of the tick genera Amblyomma, Dermacentor, Hyalomma, Ixodes and Rhipicephalus with E. canis and, for comparison, the closely-related Ehrlichia ruminantium, causative agent of heartwater in ruminants. Amblyomma and non-vector Dermacentor spp. cell lines appeared refractory to infection with E. canis but supported growth of E. ruminantium, while some, but not all, cell lines derived from Hyalomma, Ixodes and Rhipicephalus spp. ticks supported growth of both pathogens. We also illustrated and compared the ultrastructural morphology of E. canis in DH82, RSE8 and I. scapularis IDE8 cells. This study confirms that E. canis, like E. ruminantium, is able to grow not only in cell lines derived from natural and experimental tick vectors but also in a wide range of other cell lines derived from tick species not known to transmit this pathogen. PMID:26837859

  1. Tandem junction amorphous silicon solar cells

    DOEpatents

    Hanak, Joseph J.

    1981-01-01

    An amorphous silicon solar cell has an active body with two or a series of layers of hydrogenated amorphous silicon arranged in a tandem stacked configuration with one optical path and electrically interconnected by a tunnel junction. The layers of hydrogenated amorphous silicon arranged in tandem configuration can have the same bandgap or differing bandgaps.

  2. 33 CFR 401.41 - Tandem lockage.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Tandem lockage. 401.41 Section 401.41 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION, DEPARTMENT OF TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Seaway Navigation § 401.41 Tandem lockage. Where two...

  3. Tandem Mirror Reactor Systems Code (Version I)

    SciTech Connect

    Reid, R.L.; Finn, P.A.; Gohar, M.Y.; Barrett, R.J.; Gorker, G.E.; Spampinaton, P.T.; Bulmer, R.H.; Dorn, D.W.; Perkins, L.J.; Ghose, S.

    1985-09-01

    A computer code was developed to model a Tandem Mirror Reactor. Ths is the first Tandem Mirror Reactor model to couple, in detail, the highly linked physics, magnetics, and neutronic analysis into a single code. This report describes the code architecture, provides a summary description of the modules comprising the code, and includes an example execution of the Tandem Mirror Reactor Systems Code. Results from this code for two sensitivity studies are also included. These studies are: (1) to determine the impact of center cell plasma radius, length, and ion temperature on reactor cost and performance at constant fusion power; and (2) to determine the impact of reactor power level on cost.

  4. Tandem balloon catheter for coronary angioplasty.

    PubMed

    Finci, L; Meier, B; Steffenino, G; Rutishauser, W

    1986-01-01

    The Tandem balloon catheter is a triple lumen steerable catheter for coronary angioplasty with two separately inflatable balloons of different diameters. Indications and results of 26 consecutive patients treated with a Tandem balloon catheter are reviewed. Adequate distal pressure measurements were obtained in 71% of the cases. In ten patients, the Tandem balloon catheter was selected for two stenoses in different segments of the same coronary artery. Angioplasty was successful for all lesions in five and for at least the strategic lesions in five patients (in one only after changing to a single-balloon catheter). In the seven patients with stenoses in two different coronary arteries of various calibers, angioplasty was successful for both vessels in three and for one vessel in four patients. In the six patients with a very tight stenosis, where the Tandem balloon catheter was selected to predilate with the small balloon, the procedure was technically successful in all, but there was a myocardial infarction in one patient. In the three patients with a chronic total occlusion, where the stiffness of the Tandem balloon was the reason for selection, one recanalization was successful. The Tandem balloon catheter provides a handy tool for complex coronary angioplasty. It offers comparable ease in manipulation and pressure transmission and may save time, money, and radiation exposure by avoiding catheter exchanges. PMID:2949848

  5. Determination and quantification of the in vitro activity of Aloe marlothii (A. Berger) subsp. marlothii and Elephantorrhiza elephantina (Burch.) skeels acetone extracts against Ehrlichia ruminantium.

    PubMed

    Naidoo, V; Zweygarth, E; Swan, G E

    2006-09-01

    An Ehrlichia ruminantium culture system was utilized for the anti-rickettsial evaluation of two ethnoveterinary plants, Elephantorrhiza elephantina and Aloe marlothii. Well-established E. ruminantium cultures were incubated with the plant leaf acetone extracts and compared to oxytetracycline and untreated controls. Effectivity was established by comparing the percentage parasitised cells and the calculation of both EC50 and extrapolated EC90 in microg/ml. The plant extracts were also screened for antibacterial activity using bioautography. Elephantorrhiza elephantina and A. marlothii demonstrated anti-ehrlichial activity with an EC50 of 111.4 and 64.5 microg/ml and EC90 of 228.9 and 129.9 microg/ml, respectively. The corresponding EC50 and EC90 for oxytetracycline was 0.29 and 0.08 microg/ml. Both plants appeared to produce their inhibitory activity by a similar mechanism, unrelated to that of the tetracyclines. Both the plant acetone extracts demonstrated antibacterial activity against Escherichia coli and Staphylococcus aureus (ATCC strains). PMID:17058439

  6. Prevalence of antibodies against Rickettsia conorii, Babesia canis, Ehrlichia canis, and Anaplasma phagocytophilum antigens in dogs from the Stretto di Messina area (Italy).

    PubMed

    Pennisi, Maria-Grazia; Caprì, Alessandra; Solano-Gallego, Laia; Lombardo, Gabriella; Torina, Alessandra; Masucci, Marisa

    2012-12-01

    The aims of this study were to determine the seroprevalence for Rickettsia conorii, Ehrlichia canis, Anaplasma phagocytophilum, and Babesia canis in outdoor-kennelled dogs (n=249) from the Stretto di Messina (Italy) and to compare seroprevalence in 2 public shelters and 4 privately-owned kennels where different tick-preventive measures were implemented in order to focus on the specific sanitary risk posed by public shelters in southern Italy for tick-borne pathogens. R. conorii (72%) and B. canis (70%) were the most prevalent infections when compared to E. canis (46%) and A. phagocytophilum (38%). Seroprevalence for R. conorii, E. canis, and A. phagocytophilum was significantly higher in public shelters than in private kennels. However, B. canis seropositivity was similar in both types of kennels. In addition, in private kennels where a regular ectocide treatment was carried out by means of spot-on devices, dogs did not present E. canis and A. phagocytophilum antibodies. One hundred fifty-one dogs out of 249 (61%) were seropositive to more than one pathogen with R. conorii and B. canis the most common ones. Coinfections were more frequently found in public-shelter dogs. This study demonstrated high seroprevalences against R. conorii, B. canis, E. canis, and A. phagocytophilum in kennelled dogs from both coastal sites of the Stretto di Messina and the importance of regular tick-bite prevention by means of individual spot-on devices. PMID:23140895

  7. The prevalence of Ehrlichia canis, Anaplasma platys and Babesia spp. in dogs in Nueva Ecija, Philippines based on multiplex polymerase chain reaction (mPCR) assay.

    PubMed

    Corales, Joyce Marielle I; Viloria, Victoria V; Venturina, Virginia M; Mingala, Claro N

    2014-01-01

    The aim of the study was to determine the prevalence of Ehrlichia canis, Anaplasma platys and Babesia spp. in dogs. It describes the practice of veterinarians in detecting tick-borne diseases in Nueva Ecija, Philippines. Seventy blood samples were collected and were subjected to multiplex PCR for the detection of E. canis, Babesia spp. and A. platys. The prevalence of babesiosis is the highest in Cabanatuan City (2/10), while a 10% prevalence (1/10) was observed in Science City of Muñoz, Talavera and Sta. Rosa. E. canis were only detected in Cabanatuan City. However, no anaplasmosis was detected in any area. The prevalence of babesiosis and ehrlichiosis in Nueva Ecija is 7.14% (5/70) and 2.85% (2/70) respectively. In addition, 70% (7/10) of the Nueva Ecija veterinary practitioners encountered cases of suspected ehrlichiosis in their practice. The diagnosis of ehrlichiosis is based primarily on presented clinical signs and complete blood counts, which include a platelet count. Of the 10 respondents, half utilized test kits while 90% interpreted blood samples. Meanwhile, only 60% of the respondents used an ELISA test kit for ehrlichiosis. For some practitioners, the main reason for not utilizing a kit is the high cost. None of the respondents had previously attended cases of suspected anaplasmosis. Only one respondent diagnosed a case of babesiosis by blood smear microscopy. PMID:25706424

  8. A serological and molecular survey of Babesia vogeli, Ehrlichia canis and Rickettsia spp. among dogs in the state of Maranhão, northeastern Brazil.

    PubMed

    da Costa, Andréa Pereira; Costa, Francisco Borges; Labruna, Marcelo Bahia; Silveira, Iara; Moraes-Filho, Jonas; Soares, João Fábio; Spolidorio, Mariana Granziera; Guerra, Rita de Maria Seabra Nogueira de Candanedo

    2015-01-01

    This study evaluated exposure and infection by tick-borne agents (Babesia vogeli, Ehrlichia canis and Rickettsia spp.) in 172 dogs in rural areas and 150 dogs in urban areas of the municipality of Chapadinha, state of Maranhão, northeastern Brazil, using molecular and serological methods. Overall, 16.1% of the sampled dogs (52/322) were seroreactive to B. vogeli, with endpoint titers ranging from 40 to 640. For E. canis, 14.6% of the dogs (47/322) were seroreactive, with endpoint titers from 80 to 163,840. Antibodies reactive to at least one of the five species of Rickettsia were detected in 18.9% of the dogs (61/322), with endpoint titers ranging from 64 to 4,096. High endpoint titers were observed for Rickettsia amblyommii. Three (0.9%) and nine (2.8%) canine blood samples were PCR-positive for Babesia spp. and E. canis. The ticks collected from urban dogs were all Rhipicephalus sanguineus sensu lato, whereas the rural dogs were infested by R. sanguineus s.l, Amblyomma cajennense sensu lato and Amblyomma ovale. One A. ovale tick was found to be infected by Rickettsia bellii. This study provides an epidemiological background for controlling and preventing canine tick-borne diseases in a neglected region of Brazil. PMID:25909250

  9. Development of a sensitive and specific indirect enzyme-linked immunosorbent assay based on a baculovirus recombinant antigen for detection of specific antibodies against Ehrlichia canis.

    PubMed

    López, Lissett; Venteo, Angel; Aguirre, Enara; García, Marga; Rodríguez, Majosé; Amusátegui, Inmaculada; Tesouro, Miguel A; Vela, Carmen; Sainz, Angel; Rueda, Paloma

    2007-11-01

    An indirect enzyme-linked immunosorbent assay (ELISA) based on baculovirus recombinant P30 protein of Ehrlichia canis and the 1BH4 anticanine IgG monoclonal antibody was developed and evaluated by examining a panel of 98 positive and 157 negative sera using the indirect fluorescent antibody (IFA) test as the reference technique. The P30-based ELISA appeared to be sensitive and specific (77.55% and 95.54%, respectively) when qualitative results (positive/negative) were compared with those of the IFA test; the coefficient of correlation (R) between the 2 tests was 0.833. Furthermore, it was possible to establish a mathematical formula for use in comparing the results of both techniques. These results indicate that recombinant P30 antigen-based ELISA is a suitable alternative of the IFA test for simple, consistent, and rapid serodiagnosis of canine ehrlichiosis. Moreover, the use of this recombinant protein as antigen offers a great advantage for antigen preparation in comparison with other techniques in which the whole E. canis organism is used as antigen. PMID:17998551

  10. Production and characterization of Ehrlichia risticii, the agent of Potomac horse fever, from snails (Pleuroceridae: Juga spp.) in aquarium culture and genetic comparison to equine strains.

    PubMed

    Reubel, G H; Barlough, J E; Madigan, J E

    1998-06-01

    We report on the production and characterization of Ehrlichia risticii, the agent of Potomac horse fever (PHF), from snails (Pleuroceridae: Juga spp.) maintained in aquarium culture and compare it genetically to equine strains. Snails were collected from stream waters on a pasture in Siskiyou County, Calif., where PHF is enzootic and were maintained for several weeks in freshwater aquaria in the laboratory. Upon exposure to temperatures above 22 degrees C the snails released trematode cercariae tentatively identified as virgulate cercariae. Fragments of three different genes (genes for 16S rRNA, the groESL heat shock operon, and the 51-kDa major antigen) were amplified from cercaria lysates by PCR and sequenced. Genetic information was also obtained from E. risticii strains from horses with PHF. The PCR positivity of snail secretions was associated with the presence of trematode cercariae. Sequence analysis of the three genes indicated that the source organism closely resembled E. risticii, and the sequences of all three genes were virtually identical to those of the genes of an equine E. risticii strain from a property near the snail collection site. Phylogenetic analyses of the three genes indicated the presence of geographical E. risticii strain clusters. PMID:9620368

  11. Cellular immune responses induced in vitro by Ehrlichia ruminantium secreted proteins and identification of vaccine candidate peptides.

    PubMed

    Thema, Nontobeko; Pretorius, Alri; Tshilwane, Selaelo I; Liebenberg, Junita; Steyn, Helena; Van Kleef, Mirinda

    2016-01-01

    Secreted proteins are reported to induce cell-mediated immunity characterised by the production of interferon-gamma (IFN)-γ. In this study three open reading frames (ORFs) (Erum8060, Erum7760, Erum5000) encoding secreted proteins were selected from the Ehrlichia ruminantium (Welgevonden) genome sequence using bioinformatics tools to determine whether they induce a cellular immune response in vitro with mononuclear cells from needle and tick infected animals. The whole recombinant protein of the three ORFs as well as four adjacent fragments of the Erum5000 protein (Erum5000A, Erum5000B, Erum5000C, Erum5000D) were successfully expressed in a bacterial expression system which was confirmed by immunoblots using anti-His antibodies and sheep sera. These recombinant proteins were assayed with immune sheep and cattle peripheral blood mononuclear cells (PBMCs), spleen and lymph node (LN) cells to determine whether they induce recall cellular immune responses in vitro. Significant proliferative responses and IFN-γ production were evident for all recombinant proteins, especially Erum5000A, in both ruminant species tested. Thus overlapping peptides spanning Erum5000A were synthesised and peptides that induce proliferation of memory CD4+ and CD8+ T cells and production of IFN-γ were identified. These results illustrate that a Th1 type immune response was elicited and these recombinant proteins and peptides may therefore be promising candidates for development of a heartwater vaccine. PMID:27608502

  12. Optimizing a tandem disk model

    SciTech Connect

    Healey, J.V.

    1983-07-01

    A very simple physicomathematical model, in which thin straight blades with zero drag skim across a plane rectangular disk, shows that the maximum power coefficient attains the classical maximum of 0.593 over a range of T and a zero or small negative value of alpha/sub 0/. This maximum appears independent of sigma and there are values of T and alpha/sub 0/ for which the speed through the disk becomes complex and the model breaks down. Extending this model to a tandem disk system leads to a difficulty in defining the power coefficient. Attempts to optimize the system output based on reference areas A/sub 1/, A/sub 2/, and A/sub 4/ prove futile and the sum of the coefficients is chosen for this purpose. For thin blades and zero drag the analytic solution is available and it shows that the maximum value of 2 X 0.593 is attained over a narrow range of slightly negative alpha/sub 0/ (blade nose in) and medium values of T. The maximum is independent of sigma. As T is increased, the model breaks down either after C /SUB psum/ becomes large and negative or after backflow through the downwind disk occurs. There appears to be no requirement on load distribution between the disks. By comparison, modeling a machine with NACA 0012 blades at Re = 1.34 X 10/sup 6/ shows that the maximum value of C /SUB psum/ depends on the solidity. For example, at sigma = 0.4, the maximum value of C /SUB psum/ is 83% of 2 X 0.593. At such high values of sigma, however, the ranges of alpha/sub 0/ and T over which solutions are available become very limited.

  13. Tandem Catalysis Utilizing Olefin Metathesis Reactions.

    PubMed

    Zieliński, Grzegorz K; Grela, Karol

    2016-07-01

    Since olefin metathesis transformation has become a favored synthetic tool in organic synthesis, more and more distinct non-metathetical reactions of alkylidene ruthenium complexes have been developed. Depending on the conditions applied, the same olefin metathesis catalysts can efficiently promote isomerization reactions, hydrogenation of C=C double bonds, oxidation reactions, and many others. Importantly, these transformations can be carried out in tandem with olefin metathesis reactions. Through addition of one portion of a catalyst, a tandem process provides structurally advanced products from relatively simple substrates without the need for isolation of the intermediates. These aspects not only make tandem catalysis very attractive from a practical point of view, but also open new avenues in (retro)synthetic planning. However, in the literature, the term "tandem process" is sometimes used improperly to describe other types of multi-reaction sequences. In this Concept, a number of examples of tandem catalysis involving olefin metathesis are discussed with an emphasis on their synthetic value. PMID:27203528

  14. Titan and Enceladus mission (TANDEM)

    NASA Astrophysics Data System (ADS)

    Coustenis, A.

    2007-08-01

    Our understanding of Titan's atmosphere and surface has recently been enhanced by the data returned by the Cassini-Huygens mission. The Cassini orbiter will continue to be operational for about 3 more years during its extended mission. After this mission, any unanswered questions will forever remain unknown, unless we go back with an optimized orbital tour and advanced instrumentation. Considering the complementary nature of the geological, chemical and evolutionary history of Titan and Enceladus, we propose to carry out studies for a mission to perform an in situ exploration of these two objects in tandem. In our proposal we determine key science measurements, the types of samples that would be needed and the instrument suites for achieving the science goals. In particular, we develop conceptual designs for delivering the science payload, including orbiters, aerial platforms and probes, and define a launch/delivery/communication management architecture. This mission will require new technologies and capabilities so that the science goals can be achieved within the cost cap and acceptable risks. International participation will play a key role in achieving all the science goals of this mission. We will build this mission concept around a central core of single orbiter, a single Titan aerial probe and a core group of category 1 instruments. Aerobraking with Titan's atmosphere will be given serious consideration to minimize resource requirements and risk. This approach will allow a single orbiter to be used for both Enceladus science and Titan science with final orbit around Titan and later release of aerial probe(s) into Titan's atmosphere. The Titan aerial probe may be a Montgolfière balloon concept that will use the waster heat ~ 1000 watts from a single RTG power system. There will be a release of penetrator(s) on Enceladus also. This proposal addresses directly several of the scientific questions highlighted in the ESA Cosmic Vision 2015-2025 call, particularly

  15. Alpha particle confinement in tandem mirrors

    SciTech Connect

    Devoto, R.S.; Ohnishi, M.; Kerns, J.; Woo, J.T.

    1980-10-10

    Mechanisms leading to loss of alpha particles from non-axisymmetric tandem mirrors are considered. Stochastic diffusion due to bounce-drift resonances, which can cause rapid radial losses of high-energy alpha particles, can be suppressed by imposing a 20% rise in axisymmetric fields before the quadrupole transition sections. Alpha particles should then be well-confined until thermal energies when they enter the resonant plateau require. A fast code for computation of drift behavior in reactors is described. Sample calculations are presented for resonant particles in a proposed coil set for the Tandem Mirror Next Step.

  16. High performance polymer tandem solar cell

    NASA Astrophysics Data System (ADS)

    da Silva, Wilson Jose; Schneider, Fabio Kurt; Mohd Yusoff, Abd. Rashid Bin; Jang, Jin

    2015-12-01

    A power conversion efficiency of 9.02% is obtained for a fully solution-processed polymer tandem solar cell, based on the diketopyrrolopyrrole unit polymer as a low bandgap photoactive material in the rear subcell, in conjunction with a new robust interconnecting layer. This interconnecting layer is optically transparent, electrically conductive, and physically strong, thus, the charges can be collected and recombined in the interconnecting layer under illumination, while the charge is generated and extracted under dark conditions. This indicates that careful interface engineering of the charge-carrier transport layer is a useful approach to further improve the performance of polymer tandem solar cells.

  17. Homicidal tandem bullet wound of the chest.

    PubMed

    Bentley, A J; Busuttil, A; Clifton, B; Sibbald, P

    1997-03-01

    An unusual case of a homicidal gunshot wound to the chest is reported in which two bullets were fired in unison as tandem bullets from a handgun. At autopsy, two intact bullets were retrieved from the body of the victim, yet there was only one entrance wound and a single bullet track across the chest wall and thoracic organs. An examination of the weapon and ammunition supported the likelihood of tandem bullets and suggested the probable mechanism for this event. Very few similar cases have been documented. PMID:9095302

  18. High performance polymer tandem solar cell

    PubMed Central

    da Silva, Wilson Jose; Schneider, Fabio Kurt; Mohd Yusoff, Abd. Rashid bin; Jang, Jin

    2015-01-01

    A power conversion efficiency of 9.02% is obtained for a fully solution-processed polymer tandem solar cell, based on the diketopyrrolopyrrole unit polymer as a low bandgap photoactive material in the rear subcell, in conjunction with a new robust interconnecting layer. This interconnecting layer is optically transparent, electrically conductive, and physically strong, thus, the charges can be collected and recombined in the interconnecting layer under illumination, while the charge is generated and extracted under dark conditions. This indicates that careful interface engineering of the charge-carrier transport layer is a useful approach to further improve the performance of polymer tandem solar cells. PMID:26669577

  19. Tandem transformation of glycerol to esters.

    PubMed

    Sotenko, Maria V; Rebroš, Martin; Sans, Victor S; Loponov, Konstantin N; Davidson, Matthew G; Stephens, Gill; Lapkin, Alexei A

    2012-12-31

    Tandem transformation of glycerol via microbial fermentation and enzymatic esterification is presented. The reaction can be performed with purified waste glycerol from biodiesel production in a continuous mode, combining continuous fermentation with membrane-supported enzymatic esterification. Continuous anaerobic fermentation was optimized resulting in the productivity of 2.4 g L⁻¹ h⁻¹ of 1,3-propanediol. Biphasic esterification of 1,3-propanediol was optimized to achieve ester yield of up to 75%. A hollow fibre membrane contactor with immobilized Rhizomucor miehei lipase was demonstrated for the continuous tandem fermentation-esterification process. PMID:22796408

  20. High voltage series connected tandem junction solar battery

    DOEpatents

    Hanak, Joseph J.

    1982-01-01

    A high voltage series connected tandem junction solar battery which comprises a plurality of strips of tandem junction solar cells of hydrogenated amorphous silicon having one optical path and electrically interconnected by a tunnel junction. The layers of hydrogenated amorphous silicon, arranged in a tandem configuration, can have the same bandgap or differing bandgaps. The tandem junction strip solar cells are series connected to produce a solar battery of any desired voltage.

  1. 14 CFR 23.302 - Canard or tandem wing configurations.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Canard or tandem wing configurations. 23.302 Section 23.302 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... General § 23.302 Canard or tandem wing configurations. The forward structure of a canard or tandem...

  2. 14 CFR 23.302 - Canard or tandem wing configurations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Canard or tandem wing configurations. 23.302 Section 23.302 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... General § 23.302 Canard or tandem wing configurations. The forward structure of a canard or tandem...

  3. 14 CFR 23.302 - Canard or tandem wing configurations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Canard or tandem wing configurations. 23.302 Section 23.302 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... General § 23.302 Canard or tandem wing configurations. The forward structure of a canard or tandem...

  4. 14 CFR 23.302 - Canard or tandem wing configurations.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Canard or tandem wing configurations. 23.302 Section 23.302 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... General § 23.302 Canard or tandem wing configurations. The forward structure of a canard or tandem...

  5. 14 CFR 23.302 - Canard or tandem wing configurations.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Canard or tandem wing configurations. 23.302 Section 23.302 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... General § 23.302 Canard or tandem wing configurations. The forward structure of a canard or tandem...

  6. Analysis of 16S rRNA and 51-kilodalton antigen gene and transmission in mice of Ehrlichia risticii in virgulate trematodes from Elimia livescens snails in Ohio.

    PubMed

    Kanter, M; Mott, J; Ohashi, N; Fried, B; Reed, S; Lin, Y C; Rikihisa, Y

    2000-09-01

    Operculate snails (the family Pleuroceridae: Elimia livescens) were collected between June and October 1998 from a river in central Ohio where repeated cases of Potomac horse fever (PHF) have occurred. Of collected snails, consistently 50 to 80% carried a combination of cercariae and sporocysts of digenetic virgulate trematodes. The trematodes obtained from each snail were pooled and tested for Ehrlichia risticii, the agent of PHF, by nested PCR using primers specific to the 16S rRNA gene. Out of a total of 209 trematode pools, 50 pools were found to be positive by PCR. The DNA sequence of the 16S rRNA gene identified in one trematode pool was identical to that of the type strain of E. risticii, and the sequence of the gene identified in another pool differed from that of the type strain by 1 nucleotide. Comparison of the deduced amino acid sequence of the partial 51-kDa antigen gene from various sources revealed that Maryland, Ohio (except Ohio 081), and Kentucky strains are in a cluster distinct from the sequences obtained from sources in California and Oregon. Ohio 081 was shown previously by antigenic composition analysis to be distinct from other groups. However, all sequences examined were not segregated according to their sources: horse blood or infected trematodes. E. risticii was found to be transmittable from trematodes to mice and was subsequently passaged from infected mice to additional mice, as determined by PCR analysis. Our findings suggest the evolution of E. risticii in the natural reservoir in separate geographic regions and persistent infection of trematode populations with E. risticii during summer and early fall. The study also suggests that the mouse can be used to isolate E. risticii from the infected trematode. PMID:10970382

  7. Free light-chain proteinuria and normal renal histopathology and function in 11 dogs exposed to Lleishmania infantum, Ehrlichia canis, and Bbabesia canis.

    PubMed

    Bonfanti, Ugo; Zini, Eric; Minetti, Emanuele; Zatelli, Andrea

    2004-01-01

    The purpose of this retrospective study was to investigate the relationship among proteinuria consisting of immunoglobulin free light chains (FLCs), renal histopathologic findings, and routine markers of renal function in 11 dogs exposed to Leishmania infantum (n = 8), Ehrlichia canis (n = 2), and Babesia canis (n = 1). FLC proteinuria was suspected based on identification of a 22- to 27-kDa band by sodium dodecyl sulfate-agarose gel electrophoresis (SDS-AGE) and later confirmed by immunofixation electrophoresis. SDS-AGE identified an isolated band of 22-27 kDa in 8 dogs, whereas the remaining 3 had a 22- to 27-kDa band and an additional band of 67-72 kDa. The median urine protein-to-urine creatinine ratio was 0.37 (range, 0.11-2.24) and increased ratios were found in 6 dogs (54.5%) (reference value, <0.7). All dogs underwent histologic examination of renal percutaneous biopsy specimens and determination of serum creatinine and urea concentrations. Tissue samples for light microscopy were stained with hematoxylin-eosin, periodic acid-Schiff, Goldners trichrome, and methenamine silver. In the study group, the glomerular tufts, mesangium, tubulointerstitium, and vessels appeared unaffected. The median serum creatinine concentration in these 11 dogs was 1.3 mg/dL (range, 0.8-1.5 mg/dL; reference range, 0.6-1.5 mg/dL), whereas the concentration for urea was 28 mg/dL (range, 22-52 mg/dL; reference range, 20-50 mg/dL). All dogs had normal renal morphology and had normal serum creatinine and urea concentrations, suggesting that immunoglobulin FLC may be detected in the urine of dogs exposed to L. infantum, E. canis, and B. canis without any apparent structural or functional renal derangement. PMID:15515575

  8. Comparative Evaluation of the Vector Competence of Four South American Populations of the Rhipicephalus sanguineus Group for the Bacterium Ehrlichia canis, the Agent of Canine Monocytic Ehrlichiosis

    PubMed Central

    Moraes-Filho, Jonas; Krawczak, Felipe S.; Costa, Francisco B.; Soares, João Fábio; Labruna, Marcelo B.

    2015-01-01

    This study compared the vector competence of four populations of Rhipicephalus sanguineus group ticks for the bacterium Ehrlichia canis, the agent of canine monocytic ehrlichiosis (CME). Ticks (larvae and nymphs) from the four populations—one from São Paulo state, southeastern Brazil (BSP), one from Rio Grande do Sul state, southern Brazil (BRS), one from Argentina (ARG), and one from Uruguay (URU)–were exposed to E. canis infection by feeding on dogs that were experimentally infected with E. canis. Engorged ticks (larvae and nymphs) were allowed to molt to nymphs and adults, respectively, which were tested by molecular analysis (E. canis-specific PCR assay) and used to infest naïve dogs. Through infestation of adult ticks on naïve dogs, after nymphal acquisition feeding on E. canis-infected dogs, only the BSP population was shown to be competent vectors of E. canis, i.e., only the dogs infested with BSP adult ticks developed clinical illness, seroconverted to E. canis, and yielded E. canis DNA by PCR. This result, demonstrated by two independent replications, is congruent with epidemiological data, since BSP ticks were derived from São Paulo state, Brazil, where CME is highly endemic. On the other hand, BRS, ARG, and URU ticks were derived from a geographical region (South America southern cone) where CME has never been properly documented. Molecular analysis of unfed adults at 30 days post molting support these transmission results, since none of the BRS, ARG, and URU ticks were PCR positive, whereas 1% of the BSP nymphs and 31.8% of the BSP adults contained E. canis DNA. We conclude that the absence or scarcity of cases of CME due to E. canis in the South America southern cone is a result of vector incompetence of the R. sanguineus group ticks that prevail on dogs in this part of South America. PMID:26414283

  9. Comparative Evaluation of the Vector Competence of Four South American Populations of the Rhipicephalus sanguineus Group for the Bacterium Ehrlichia canis, the Agent of Canine Monocytic Ehrlichiosis.

    PubMed

    Moraes-Filho, Jonas; Krawczak, Felipe S; Costa, Francisco B; Soares, João Fábio; Labruna, Marcelo B

    2015-01-01

    This study compared the vector competence of four populations of Rhipicephalus sanguineus group ticks for the bacterium Ehrlichia canis, the agent of canine monocytic ehrlichiosis (CME). Ticks (larvae and nymphs) from the four populations-one from São Paulo state, southeastern Brazil (BSP), one from Rio Grande do Sul state, southern Brazil (BRS), one from Argentina (ARG), and one from Uruguay (URU)-were exposed to E. canis infection by feeding on dogs that were experimentally infected with E. canis. Engorged ticks (larvae and nymphs) were allowed to molt to nymphs and adults, respectively, which were tested by molecular analysis (E. canis-specific PCR assay) and used to infest naïve dogs. Through infestation of adult ticks on naïve dogs, after nymphal acquisition feeding on E. canis-infected dogs, only the BSP population was shown to be competent vectors of E. canis, i.e., only the dogs infested with BSP adult ticks developed clinical illness, seroconverted to E. canis, and yielded E. canis DNA by PCR. This result, demonstrated by two independent replications, is congruent with epidemiological data, since BSP ticks were derived from São Paulo state, Brazil, where CME is highly endemic. On the other hand, BRS, ARG, and URU ticks were derived from a geographical region (South America southern cone) where CME has never been properly documented. Molecular analysis of unfed adults at 30 days post molting support these transmission results, since none of the BRS, ARG, and URU ticks were PCR positive, whereas 1% of the BSP nymphs and 31.8% of the BSP adults contained E. canis DNA. We conclude that the absence or scarcity of cases of CME due to E. canis in the South America southern cone is a result of vector incompetence of the R. sanguineus group ticks that prevail on dogs in this part of South America. PMID:26414283

  10. Comparative Proteomic Profiling of Ehrlichia ruminantium Pathogenic Strain and Its High-Passaged Attenuated Strain Reveals Virulence and Attenuation-Associated Proteins

    PubMed Central

    Marcelino, Isabel; Ventosa, Miguel; Pires, Elisabete; Müller, Markus; Lisacek, Frédérique; Lefrançois, Thierry; Vachiery, Nathalie; Coelho, Ana Varela

    2015-01-01

    The obligate intracellular bacterium Ehrlichia ruminantium (ER) causes heartwater, a fatal tick-borne disease in livestock. In the field, ER strains present different levels of virulence, limiting vaccine efficacy, for which the molecular basis remains unknown. Moreover, there are no genetic tools currently available for ER manipulation, thus limiting the knowledge of the genes/proteins that are essential for ER pathogenesis and biology. As such, to identify proteins and/or mechanisms involved in ER virulence, we performed the first exhaustive comparative proteomic analysis between a virulent strain (ERGvir) and its high-passaged attenuated strain (ERGatt). Despite their different behaviors in vivo and in vitro, our results from 1DE-nanoLC-MS/MS showed that ERGvir and ERGatt share 80% of their proteins; this core proteome includes chaperones, proteins involved in metabolism, protein-DNA-RNA biosynthesis and processing, and bacterial effectors. Conventional 2DE revealed that 85% of the identified proteins are proteoforms, suggesting that post-translational modifications (namely glycosylation) are important in ER biology. Strain-specific proteins were also identified: while ERGatt has an increased number and overexpression of proteins involved in cell division, metabolism, transport and protein processing, ERGvir shows an overexpression of proteins and proteoforms (DIGE experiments) involved in pathogenesis such as Lpd, AnkA, VirB9 and B10, providing molecular evidence for its increased virulence in vivo and in vitro. Overall, our work reveals that ERGvir and ERGatt proteomes are streamlined to fulfill their biological function (maximum virulence for ERGvir and replicative capacity for ERGatt), and we provide both pioneering data and novel insights into the pathogenesis of this obligate intracellular bacterium. PMID:26691135

  11. Development and evaluation of a loop-mediated isothermal amplification assay for detection of Ehrlichia canis DNA in naturally infected dogs using the p30 gene.

    PubMed

    Pinhanelli, V C; Costa, P N M; Silva, G; Aguiar, D M; Silva, C M L; Fachin, A L; Marins, M

    2015-01-01

    Canine monocytic ehrlichiosis (CME) is a common tick-borne disease caused by the rickettsial bacterium Ehrlichia canis (Rickettsiales: Anaplasmataceae). In view of the different stages and variable clinical signs of CME, which can overlap with those of other infections, a conclusive diagnosis can more readily be obtained by combining clinical and hematological evaluations with molecular diagnostic methods. In this study, a loop-mediated isothermal amplification (LAMP) assay targeting the p30 gene of E. canis was developed. The assay was developed using DNA extracted from E. canis-infected cultures of the macrophage cell line DH82 and samples from dogs testing positive for E. canis DNA by PCR. The LAMP assay was compared to a p30-based PCR assay, using DNA extracted from EDTA-anticoagulated blood samples of 137 dogs from an endemic region in Brazil. The LAMP assay was sensitive enough to detect a single copy of the target gene, and identified 74 (54.0%) E. canis DNA-positive samples, while the p30 PCR assay detected 50 positive samples (36.5%) among the field samples. Agreement between the two assays was observed in 42 positive and 55 negative samples. However, 32 positive samples that were not detected by the PCR assay were identified by the LAMP assay, while eight samples identified as E. canis-positive by PCR showed negative results in LAMP. The developed E. canis LAMP assay showed the potential to maximize the use of nucleic acid tests in a veterinary clinical laboratory, and to improve the diagnosis of CME. PMID:26782434

  12. Current Surveys of the Seroprevalence of Borrelia burgdorferi, Ehrlichia canis, Anaplasma phagocytophilum, Leishmania infantum, Babesia canis, Angiostrongylus vasorum and Dirofilaria immitis in Dogs in Bulgaria.

    PubMed

    Pantchev, Nikola; Schnyder, Manuela; Vrhovec, Majda Globokar; Schaper, Roland; Tsachev, Ilia

    2015-08-01

    Canine vector-borne diseases (CVBDs) have increasingly become a focus of interest in recent years. Some of the CVBDs are zoonotic and may therefore also represent a risk for the human population. Different factors are in discussion to explain the expansion of vectors and pathogens into formerly unaffected areas. Knowledge of the prevalence and distribution of CVBDs in Bulgaria is scant overall and most data rely on single case descriptions. The aim of the present study was to determine the seroprevalence of important CVBDs in 167 dogs from central-southern Bulgaria (Stara Zagora), with special emphasis on hitherto uninvestigated babesiosis and angiostrongylosis, on poorly investigated Lyme borreliosis and canine granulocytic anaplasmosis, and on the potentially zoonotic dirofilariosis and leishmaniosis. Relatively high prevalence rates were documented for anti-Babesia canis antibodies, Dirofilaria immitis antigen (16.2 %; 27/167 each), anti-Ehrlichia canis (21 %; 35/167) and anti-Anaplasma phagocytophilum antibodies (30.5 - 46.1 %; 51 - 77/167), while Borrelia burgdorferi seroprevalence was low (2.4 %; 4/167). All samples were negative for Leishmania infantum antibodies and Angiostrongylus vasorum antigen and antibodies. In total, 64.7 % (108/167) of the samples indicated infection or exposure to at least one agent and a high proportion of dual infections (39.8 %; 43/108) was demonstrated. Multiple infections with up to four different organisms were also detected. Our data underline the importance of CVBDs and especially of co-infections which could influence the clinical outcome in dogs. PMID:26152413

  13. Tandem mirror fusion-fission hybrid studies

    NASA Astrophysics Data System (ADS)

    Lee, J. D.

    1980-04-01

    The concept of combining nuclear fusion and nuclear fission techniques is discussed. Initial tandem mirror hybrid studies predict the ability to produce large amounts of fissile fuel (2 to 7 tons U233 per year from a 4000 MW plant) at a cost that adds less than 25% to the cost of power from a light water reactor.

  14. Status of BINP proton tandem accelerator

    NASA Astrophysics Data System (ADS)

    Burdakov, A.; Davydenko, V.; Dolgushin, V.; Dranichnikov, A.; Ivanov, A.; Farrell, J. P.; Khilchenko, A.; Kobets, V.; Konstantinov, S.; Krivenko, A.; Kudryavtsev, A.; Tiunov, M.; Savkin, V.; Shirokov, V.; Sorokin, I.

    2007-08-01

    The status of a unique 2.0 MeV, 10 mA proton tandem accelerator with vacuum insulation is presented. The accelerator is intended to be used in facilities generating resonant gamma rays for explosives detection and epithermal neutrons for boron neutron-capture therapy of brain tumors. A magnetically coupled DC voltage multiplier derived from an industrial ELV-type electron accelerator is used as a high voltage source for the accelerator. A dc high current negative ion source has been developed for injection into the tandem. In the tandem accelerator there is set of nested potential electrodes with openings which form a channel for accelerating the negative hydrogen ion beam and subsequently accelerating the proton beam after stripping in the gas target. The electrodes are connected to a high voltage feedthrough insulator to which required potentials are applied from the high voltage power supply by means of a resistor voltage divider. In the paper the first experimental results obtained with the vacuum insulated tandem accelerator are also given.

  15. Tandem oligonucleotide synthesis using linker phosphoramidites

    PubMed Central

    Pon, Richard T.; Yu, Shuyuan

    2005-01-01

    Multiple oligonucleotides of the same or different sequence, linked end-to-end in tandem can be synthesized in a single automated synthesis. A linker phosphoramidite [R. T. Pon and S. Yu (2004) Nucleic Acids Res., 32, 623–631] is added to the 5′-terminal OH end of a support-bound oligonucleotide to introduce a cleavable linkage (succinic acid plus sulfonyldiethanol) and the 3′-terminal base of the new sequence. Conventional phosphoramidites are then used for the rest of the sequence. After synthesis, treatment with ammonium hydroxide releases the oligonucleotides from the support and cleaves the linkages between each sequence. Mixtures of one oligonucleotide with both 5′- and 3′-terminal OH ends and other oligonucleotides with 5′-phosphorylated and 3′-OH ends are produced, which are deprotected and worked up as a single product. Tandem synthesis can be used to make pairs of PCR primers, sets of cooperative oligonucleotides or multiple copies of the same sequence. When tandem synthesis is used to make two self-complementary sequences, double-stranded structures spontaneously form after deprotection. Tandem synthesis of oligonucleotide chains containing up to six consecutive 20mer (120 bases total), various trinucleotide codons and primer pairs for PCR, or self-complementary strands for in situ formation of double-stranded DNA fragments has been demonstrated. PMID:15814811

  16. 25 MV tandem accelerator at Oak Ridge

    SciTech Connect

    Jones, C.M.

    1980-01-01

    A new heavy-ion accelerator facility is under construction at the Oak Ridge National Laboratory. A brief description of the scope and status of this project is presented with emphasis on the first operational experience with the 25 MV tandem accelerator.

  17. Modelling of tandem cell temperature coefficients

    SciTech Connect

    Friedman, D.J.

    1996-05-01

    This paper discusses the temperature dependence of the basic solar-cell operating parameters for a GaInP/GaAs series-connected two-terminal tandem cell. The effects of series resistance and of different incident solar spectra are also discussed.

  18. Organic Tandem Solar Cells: Design and Formation

    NASA Astrophysics Data System (ADS)

    Chen, Chun-Chao

    In the past decade, research on organic solar cells has gone through an important development stage leading to major enhancements in power conversion efficiency, from 4% to 9% in single-junction devices. During this period, there are many novel processing techniques and device designs that have been proposed and adapted in organic solar-cell devices. One well-known device architecture that helps maximize the solar cell efficiency is the multi-junction tandem solar-cell design. Given this design, multiple photoactive absorbers as subcells are stacked in a monolithic fashion and assembled via series connection into one complete device, known as the tandem solar cell. Since multiple absorbers with different optical energy bandgaps are being applied in one tandem solar-cell device, the corresponding solar cell efficiency is maximized through expanded absorption spectrum and reduced carrier thermalization loss. In Chapter 3, the architecture of solution-processible, visibly transparent solar cells is introduced. Unlike conventional organic solar-cell devices with opaque electrodes (such as silver, aluminum, gold and etc.), the semi-transparent solar cells rely on highly transparent electrodes and visibly transparent photoactive absorbers. Given these two criteria, we first demonstrated the visibly transparent single-junction solar cells via the polymer absorber with near-infrared absorption and the top electrode based on solution-processible silver nanowire conductor. The highest visible transparency (400 ˜ 700 nm) of 65% was achieved for the complete device structure. More importantly, power conversion efficiency of 4% was also demonstrated. In Chapter 4, we stacked two semi-transparent photoactive absorbers in the tandem architecture in order to realize the semi-transparent tandem solar cells. A noticeable performance improvement from 4% to 7% was observed. More importantly, we modified the interconnecting layers with the incorporation of a thin conjugated

  19. Technology for large tandem mirror experiments

    SciTech Connect

    Thomassen, K.I.

    1980-09-04

    Construction of a large tandem mirror (MFTF-B) will soon begin at Lawrence Livermore National Laboratory (LLNL). Designed to reach break-even plasma conditions, the facility will significantly advance the physics and technology of magnetic-mirror-based fusion reactors. This paper describes the objectives and the design of the facility.

  20. Advances in Tandem Mirror fusion power reactors

    SciTech Connect

    Perkins, L.J.; Logan, B.G.

    1986-05-20

    The Tandem Mirror exhibits several distinctive features which make the reactor embodiment of the principle very attractive: Simple low-technology linear central cell; steady-state operation; high-..beta.. operation; no driven current or disruptions; divertorless operation; direction conversion of end-loss power; low-surface heat loads; and advanced fusion fuel capability. In this paper, we examine these features in connection with two tandem mirror reactor designs, MARS and MINIMARS, and several advanced reactor concepts including the wall-stabilized reactor and the field-reversed mirror. With a novel compact end plug scheme employing octopole stabilization, MINIMARS is expressly designed for short construction times, factory-built modules, and a small (600 MWe) but economic reactor size. We have also configured the design for low radioactive afterheat and inherent/passive safety under LOCA/LOFA conditions, thereby obviating the need for expensive engineered safety systems. In contrast to the complex and expensive double-quadrupole end-cell of the MARS reactor, the compact octopole end-cell of MINIMARS enables ignition to be achieved with much shorter central cell lengths and considerably improves the economy of scale for small (approx.250 to 600 MWe) tandem mirror reactors. Finally, we examine the prospects for realizing the ultimate potential of the tandem mirror with regard to both innovative configurations and novel neutron energy conversion schemes, and stress that advanced fuel applications could exploit its unique reactor features.

  1. Tandem mirror next step conceptual design

    SciTech Connect

    Doggett, J.N.; Damm, C.C.; Bulmer, R.H.

    1980-10-14

    A study was made to define the features of the experimental mirror fusion device - The Tandem Mirror Next Step, or TMNS - that will bridge the gap between present mirror confinement experiments and a power-producing reactor. We outline the project goals, describe some initial device parameters, and relate the technological requirements to ongoing development programs.

  2. Vortex interaction between two tandem flexible propulsors

    NASA Astrophysics Data System (ADS)

    Park, Sung Goon; Sung, Hyung Jin; Flow Control Laboratory Team

    2015-11-01

    Schooling behaviors of flying and swimming animals are widespread phenomena in nature. Inspired by schooling behaviors of swimming jellyfish, self-propelling flexible bodies with a paddling-based locomotion were modeled in a tandem configuration. The interactions between surrounding fluids and propulsors were considered by using the immersed boundary method. The hydrodynamic patterns generated by the interactions between tandem flexible propulsors were analyzed in the presen study. As a result of the flow-mediated interactions between them, stable configurations were formed spontaneously in which the gap distance between propulsors increased and decreased during the contraction and relaxation phases of the upstream propulsor. The stable configuration was not affected by the initial gap distance but influenced by the phase difference in the flapping frequency between them. Both tandem propulsors benefited from the tandem configuration in terms of the locomotion as compared with an isolated propulsor. This study was supported by the Creative Research Initiatives (No. 2015-001828) program of the National Research Foundation of Korea (MSIP).

  3. Inverted Three-Junction Tandem Thermophotovoltaic Modules

    NASA Technical Reports Server (NTRS)

    Wojtczuk, Steven

    2012-01-01

    An InGaAs-based three-junction (3J) tandem thermophotovoltaic (TPV) cell has been investigated to utilize more of the blackbody spectrum (from a 1,100 C general purpose heat source GPHS) efficiently. The tandem consists of three vertically stacked subcells, a 0.74-eV InGaAs cell, a 0.6- eV InGaAs cell, and a 0.55-eV InGaAs cell, as well as two interconnecting tunnel junctions. A greater than 20% TPV system efficiency was achieved by another group with a 1,040 C blackbody using a single-bandgap 0.6- eV InGaAs cell MIM (monolithic interconnected module) (30 lateral junctions) that delivered about 12 V/30 or 0.4 V/junction. It is expected that a three-bandgap tandem MIM will eventually have about 3 this voltage (1.15 V) and about half the current. A 4 A/cm2 would be generated by a single-bandgap 0.6-V InGaAs MIM, as opposed to the 2 A/cm2 available from the same spectrum when split among the three series-connected junctions in the tandem stack. This would then be about a 50% increase (3xVoc, 0.5xIsc) in output power if the proposed tandem replaced the single- bandgap MIM. The advantage of the innovation, if successful, would be a 50% increase in power conversion efficiency from radioisotope heat sources using existing thermophotovoltaics. Up to 50% more power would be generated for radioisotope GPHS deep space missions. This type of InGaAs multijunction stack could be used with terrestrial concentrator solar cells to increase efficiency from 41 to 45% or more.

  4. Comparison of the nucleotide sequences of 16S rRNA, 444 Ep-ank, and groESL heat shock operon genes in naturally occurring Ehrlichia equi and human granulocytic ehrlichiosis agent isolates from Northern California.

    PubMed

    Chae, J S; Foley, J E; Dumler, J S; Madigan, J E

    2000-04-01

    We examined 11 naturally occurring isolates of Ehrlichia equi in horses and two human granulocytic ehrlichiosis agent isolates in California for sequence diversity in three genes. Ehrlichia equi isolates were from Sierra (n = 6), Mendocino (n = 3), Sonoma (n = 1), and Marin (n = 1) counties, and human granulocytic ehrlichiosis (HGE) agent isolates were obtained from Humboldt county. PCR with specific primers for 16S rRNA, 444 Ep-ank and groESL heat shock operon genes successfully produced amplicons for all 13 clinical samples. The 444 Ep-ank gene of the HGE agent and E. equi isolates from northern California is different from the eastern U.S. isolates BDS and USG3. The translated amino acid sequence of the groESL heat shock operon gene fragment is identical among E. equi, the HGE agent, and E. phagocytophila, with the exception of the northern Californian equine CASOLJ isolate. Microheterogeneity was observed in the 16S rRNA gene sequences of HGE agent and E. equi isolates from northern California. These results suggest that E. equi and the HGE agent found in California are similar or identical but may differ from the isolates of equine and human origin found in the eastern United States. PMID:10747108

  5. Tritium measurements with a tandem accelerator

    NASA Astrophysics Data System (ADS)

    Middleton, R.; Klein, J.; Fink, D.

    1990-06-01

    Tritium concentrations ( 3H: 2H) of less than 10 -15 are readily measurable with almost any tandem accelerator and with an overall detection efficiency as high as 4.5%. The isobar, 3He, and other potential sources of interference (mainly 6Li, 2H and 1H) can all be removed by an absorber in front of the triton detector, so there is little need for analyzing elements other than the negative-and positive-ion magnets found on most tandems. The technique is particularly well suited for detecting tritium in deuterium absorbed in a metal and testing for cold fusion. We caution that tritium can occur in commercial deuterium and heavy water from sources other than cold fusion; one sample was observed to have a tritium-to-deuterium ratio of 10 -10.

  6. Locomotion by Tandem and Parallel Wings

    NASA Astrophysics Data System (ADS)

    Tanida, Yoshimichi

    A two-dimensional analysis was carried out on the locomotion by tandem and parallel wings in relation to the free flight of dragonflies and beetles, remarking the mutual interference between fore and hind wings. The results obtained are summarized as follows: In the case of tandem wings, (1)High thrust and propulsive efficiency can be achieved when the forewing oscillates with a definite phase lag behind the hindwing, as in the case of real dragonflies, (2)Somewhat smaller amplitude of hindwing leads to optimum condition for work sharing of two wings, (3)The hard forewing does not serve for the thrust and propulsive efficiency, whereas the hard hindwing does for the augmentation of them; In the case of parallel wings, (4)The hard wing placed near the soft wing acts nearly as an infinite plate, as for the ground effect, increasing both thrust and propulsive efficiency.

  7. Tandem microwave waste remediation and decontamination system

    DOEpatents

    Wicks, George G.; Clark, David E.; Schulz, Rebecca L.

    1999-01-01

    The invention discloses a tandem microwave system consisting of a primary chamber in which microwave energy is used for the controlled combustion of materials. A second chamber is used to further treat the off-gases from the primary chamber by passage through a susceptor matrix subjected to additional microwave energy. The direct microwave radiation and elevated temperatures provide for significant reductions in the qualitative and quantitative emissions of the treated off gases. The tandem microwave system can be utilized for disinfecting wastes, sterilizing materials, and/or modifying the form of wastes to solidify organic or inorganic materials. The simple design allows on-site treatment of waste by small volume waste generators.

  8. Nucleic acid recognition by tandem helical repeats.

    PubMed

    Rubinson, Emily H; Eichman, Brandt F

    2012-02-01

    Protein domains constructed from tandem α-helical repeats have until recently been primarily associated with protein scaffolds or RNA recognition. Recent crystal structures of human mitochondrial termination factor MTERF1 and Bacillus cereus alkylpurine DNA glycosylase AlkD bound to DNA revealed two new superhelical tandem repeat architectures capable of wrapping around the double helix in unique ways. Unlike DNA sequence recognition motifs that rely mainly on major groove read-out, MTERF and ALK motifs locate target sequences and aberrant nucleotides within DNA by resculpting the double-helix through extensive backbone contacts. Comparisons between MTERF and ALK repeats, together with recent advances in ssRNA recognition by Pumilio/FBF (PUF) domains, provide new insights into the fundamental principles of protein-nucleic acid recognition. PMID:22154606

  9. Electron irradiation of tandem junction solar cells

    NASA Technical Reports Server (NTRS)

    Anspaugh, B. E.; Miyahira, T. F.; Scott-Monck, J. A.

    1979-01-01

    The electrical behavior of 100 micron thick tandem junction solar cells manufactured by Texas Instruments was studied as a function of 1 MeV electron fluence, photon irradiation, and 60 C annealing. These cells are found to degrade rapidly with radiation, the most serious loss occurring in the blue end of the cell's spectral response. No photon degradation was found to occur, but the cells did anneal a small amount at 60 C.

  10. Current and lattice matched tandem solar cell

    DOEpatents

    Olson, Jerry M.

    1987-01-01

    A multijunction (cascade) tandem photovoltaic solar cell device is fabricated of a Ga.sub.x In.sub.1-x P (0.505.ltoreq.X.ltoreq.0.515) top cell semiconductor lattice matched to a GaAs bottom cell semiconductor at a low-resistance heterojunction, preferably a p+/n+ heterojunction between the cells. The top and bottom cells are both lattice matched and current matched for high efficiency solar radiation conversion to electrical energy.

  11. DDES and IDDES of tandem cylinders.

    SciTech Connect

    Balakrishnan, R.; Garbaruk, A.; Shur, M.; Strelets, M.; Spalart, P.; New Technologies and Services - Russia; St.-Peterburg State Polytechnic Univ.; Boeing Commercial Airplanes

    2010-09-09

    The paper presents an overview of the authors contribution to the BANC-I Workshop on the flow past tandem cylinders (Category 2). It includes an outline of the simulation approaches, numerics, and grid used, the major results of the simulations, their comparison with available experimental data, and some preliminary conclusions. The effect of varying the spanwise period in the simulations is strong for some quantities, and not others.

  12. Cold Climate Heat Pumps Using Tandem Compressors

    SciTech Connect

    Shen, Bo; Abdelaziz, Omar; Rice, C Keith; Baxter, Van D

    2016-01-01

    In cold climate zones, e.g. ASHRAE climate regions IV and V, conventional electric air-source heat pumps (ASHP) do not work well, due to high compressor discharge temperatures, large pressure ratios and inadequate heating capacities at low ambient temperatures. Consequently, significant use of auxiliary strip heating is required to meet the building heating load. We introduce innovative ASHP technologies as part of continuing efforts to eliminate auxiliary strip heat use and maximize heating COP with acceptable cost-effectiveness and reliability. These innovative ASHP were developed using tandem compressors, which are capable of augmenting heating capacity at low temperatures and maintain superior part-load operation efficiency at moderate temperatures. Two options of tandem compressors were studied; the first employs two identical, single-speed compressors, and the second employs two identical, vapor-injection compressors. The investigations were based on system modeling and laboratory evaluation. Both designs have successfully met the performance criteria. Laboratory evaluation showed that the tandem, single-speed compressor ASHP system is able to achieve heating COP = 4.2 at 47 F (8.3 C), COP = 2.9 at 17 F (-8.3 C), and 76% rated capacity and COP = 1.9 at -13 F (-25 C). This yields a HSPF = 11.0 (per AHRI 210/240). The tandem, vapor-injection ASHP is able to reach heating COP = 4.4 at 47 F, COP = 3.1 at 17 F, and 88% rated capacity and COP = 2.0 at -13 F. This yields a HSPF = 12.0. The system modeling and further laboratory evaluation are presented in the paper.

  13. Expression of tandem gene duplicates is often greater than twofold

    PubMed Central

    Loehlin, David W.; Carroll, Sean B.

    2016-01-01

    Tandem gene duplication is an important mutational process in evolutionary adaptation and human disease. Hypothetically, two tandem gene copies should produce twice the output of a single gene, but this expectation has not been rigorously investigated. Here, we show that tandem duplication often results in more than double the gene activity. A naturally occurring tandem duplication of the Alcohol dehydrogenase (Adh) gene exhibits 2.6-fold greater expression than the single-copy gene in transgenic Drosophila. This tandem duplication also exhibits greater activity than two copies of the gene in trans, demonstrating that it is the tandem arrangement and not copy number that is the cause of overactivity. We also show that tandem duplication of an unrelated synthetic reporter gene is overactive (2.3- to 5.1-fold) at all sites in the genome that we tested, suggesting that overactivity could be a general property of tandem gene duplicates. Overactivity occurs at the level of RNA transcription, and therefore tandem duplicate overactivity appears to be a previously unidentified form of position effect. The increment of surplus gene expression observed is comparable to many regulatory mutations fixed in nature and, if typical of other genomes, would shape the fate of tandem duplicates in evolution. PMID:27162370

  14. TandEM: Titan and Enceladus mission

    USGS Publications Warehouse

    Coustenis, A.; Atreya, S.K.; Balint, T.; Brown, R.H.; Dougherty, M.K.; Ferri, F.; Fulchignoni, M.; Gautier, D.; Gowen, R.A.; Griffith, C.A.; Gurvits, L.I.; Jaumann, R.; Langevin, Y.; Leese, M.R.; Lunine, J.I.; McKay, C.P.; Moussas, X.; Muller-Wodarg, I.; Neubauer, F.; Owen, T.C.; Raulin, F.; Sittler, E.C.; Sohl, F.; Sotin, C.; Tobie, G.; Tokano, T.; Turtle, E.P.; Wahlund, J.-E.; Waite, J.H.; Baines, K.H.; Blamont, J.; Coates, A.J.; Dandouras, I.; Krimigis, T.; Lellouch, E.; Lorenz, R.D.; Morse, A.; Porco, C.C.; Hirtzig, M.; Saur, J.; Spilker, T.; Zarnecki, J.C.; Choi, E.; Achilleos, N.; Amils, R.; Annan, P.; Atkinson, D.H.; Benilan, Y.; Bertucci, C.; Bezard, B.; Bjoraker, G.L.; Blanc, M.; Boireau, L.; Bouman, J.; Cabane, M.; Capria, M.T.; Chassefiere, E.; Coll, P.; Combes, M.; Cooper, J.F.; Coradini, A.; Crary, F.; Cravens, T.; Daglis, I.A.; de Angelis, E.; De Bergh, C.; de Pater, I.; Dunford, C.; Durry, G.; Dutuit, O.; Fairbrother, D.; Flasar, F.M.; Fortes, A.D.; Frampton, R.; Fujimoto, M.; Galand, M.; Grasset, O.; Grott, M.; Haltigin, T.; Herique, A.; Hersant, F.; Hussmann, H.; Ip, W.; Johnson, R.; Kallio, E.; Kempf, S.; Knapmeyer, M.; Kofman, W.; Koop, R.; Kostiuk, T.; Krupp, N.; Kuppers, M.; Lammer, H.; Lara, L.-M.; Lavvas, P.; Le, Mouelic S.; Lebonnois, S.; Ledvina, S.; Li, J.; Livengood, T.A.; Lopes, R.M.; Lopez-Moreno, J. -J.; Luz, D.; Mahaffy, P.R.; Mall, U.; Martinez-Frias, J.; Marty, B.; McCord, T.; Salvan, C.M.; Milillo, A.; Mitchell, D.G.; Modolo, R.; Mousis, O.; Nakamura, M.; Neish, C.D.; Nixon, C.A.; Mvondo, D.N.; Orton, G.; Paetzold, M.; Pitman, J.; Pogrebenko, S.; Pollard, W.; Prieto-Ballesteros, O.; Rannou, P.; Reh, K.; Richter, L.; Robb, F.T.; Rodrigo, R.; Rodriguez, S.; Romani, P.; Bermejo, M.R.; Sarris, E.T.; Schenk, P.; Schmitt, B.; Schmitz, N.; Schulze-Makuch, D.; Schwingenschuh, K.; Selig, A.; Sicardy, B.; Soderblom, L.; Spilker, L.J.; Stam, D.; Steele, A.; Stephan, K.; Strobel, D.F.; Szego, K.; Szopa

    2009-01-01

    TandEM was proposed as an L-class (large) mission in response to ESA's Cosmic Vision 2015-2025 Call, and accepted for further studies, with the goal of exploring Titan and Enceladus. The mission concept is to perform in situ investigations of two worlds tied together by location and properties, whose remarkable natures have been partly revealed by the ongoing Cassini-Huygens mission. These bodies still hold mysteries requiring a complete exploration using a variety of vehicles and instruments. TandEM is an ambitious mission because its targets are two of the most exciting and challenging bodies in the Solar System. It is designed to build on but exceed the scientific and technological accomplishments of the Cassini-Huygens mission, exploring Titan and Enceladus in ways that are not currently possible (full close-up and in situ coverage over long periods of time). In the current mission architecture, TandEM proposes to deliver two medium-sized spacecraft to the Saturnian system. One spacecraft would be an orbiter with a large host of instruments which would perform several Enceladus flybys and deliver penetrators to its surface before going into a dedicated orbit around Titan alone, while the other spacecraft would carry the Titan in situ investigation components, i.e. a hot-air balloon (Montgolfi??re) and possibly several landing probes to be delivered through the atmosphere. ?? Springer Science + Business Media B.V. 2008.

  15. Molecular detection of Anaplasma platys, Ehrlichia canis, Hepatozoon canis and Rickettsia monacensis in dogs from Maio Island of Cape Verde archipelago.

    PubMed

    Lauzi, Stefania; Maia, João P; Epis, Sara; Marcos, Ricardo; Pereira, Cristina; Luzzago, Camilla; Santos, Marta; Puente-Payo, Pablo; Giordano, Alessia; Pajoro, Massimo; Sironi, Giuseppe; Faustino, Augusto

    2016-07-01

    Tick-borne diseases are emerging worldwide and have an important zoonotic relevance. Dogs play an important role in the epidemiology of several zoonotic tick-borne pathogens acting as sentinels and/or reservoirs. This study focused on the molecular identification of tick-borne pathogens in blood samples of 153 autochthonous asymptomatic dogs in Maio Island, Cape Verde archipelago. Eighty-four (54.9%) dogs were positive for one or more pathogens. Fifty-five (35.9%) dogs were infected with Hepatozoon canis, 53 (34.6%) with Anaplasma platys, five (3.3%) with Ehrlichia canis and Rickettsia monacensis, an emerging human pathogen, was also identified in a single dog (0.7%). The former three pathogens cause important canine tick-borne diseases that are transmitted or potentially transmitted by Rhipicephalus sanguineus s.l., the only hard tick identified in Cape Verde. Furthermore, Wolbachia spp. was amplified from the blood of one dog. None of the dogs were positive for Anaplasma phagocytophilum, Borrelia burgdorferi sensu lato, Midichloria mitochondrii, Bartonella spp., Babesia spp. or Theileria spp. Fifty-four (35.3%) animals showed single infections and 30 (19.6%) co-infections, with A. platys and H. canis co-infection being the most frequent (28 dogs, 18.3%). The frequency of E. canis infection was statistically different among age groups (P=0.017), being higher among dogs older than 4 years compared to younger dogs. Infection by A. platys was also statistically different among age groups (P=0.031), being higher in dogs younger than 2 years compared to older dogs. The statistical analyses showed no significant association of PCR positivity with gender or location. The frequency of tick-borne pathogens detected in dogs in Maio Island, including R. monacensis, highlights the need to improve diagnosis and control in order to prevent the risk of transmission of these pathogens among dogs and humans living in or travelling to this touristic island. PMID:27177475

  16. Organic Light-Emitting Devices with Tandem Structure.

    PubMed

    Chiba, Takayuki; Pu, Yong-Jin; Kido, Junji

    2016-06-01

    Tandem organic light-emitting devices (OLEDs) have attracted considerable attention for solid-state lighting and flat panel displays because their tandem architecture enables high efficiency and long operational lifetime simultaneously. In the tandem OLED structure, plural light-emitting units (LEUs) are stacked in series through a charge generation layer (CGL) and an electron injection layer (EIL). In this chapter, we focus on the key features of tandem OLEDs for high efficiency and long operational lifetimes. We also demonstrate the effect of the CGL comprising a Lewis acid, an n-type semiconductor metal oxide, and an organic electron-accepting material. We discuss the two types of EILs in tandem OLEDs: alkali metals containing n-type compounds and ultra-thin metals. Finally, we focus on the recent progress of the state-of-the-art solution-processed tandem OLEDs. PMID:27573273

  17. [Tandem repeats in rodents genome and their mapping].

    PubMed

    Ostromyshenskii, D I; Kuznetsova, L S; Komissarov, A S; Kartavtseva, I V; Podgornaya, L

    2015-01-01

    Tandemly-repeated sequences represent a unique class of eukaryotic DNA. Their content in the genome of higher eukaryotes mounts to tens of percents. However, the evolution of this class of sequences is poorly-studied. In our paper, 62 families of Mus musculus tandem repeats are analyzed by bioinformatic methods, and 7 of them are analyzed by fluorescence in situ hybridization. It is shown that the same tandem repeat sets co-occure only in closely related species of mice. But even in such species we observe differences in localization on the chromosomes and the number of individual tandem repeats. With increasing evolutionary distance only some of the tandem repeat families remain common for different species. It is shown, that the use of a combination of bioinformatics and molecular biology techniques is very perspective for further studies of the evolution of tandem repeats. PMID:26035967

  18. Flexible and fragmentable tandem photosensitive nanocrystal skins

    NASA Astrophysics Data System (ADS)

    Akhavan, S.; Uran, C.; Bozok, B.; Gungor, K.; Kelestemur, Y.; Lesnyak, V.; Gaponik, N.; Eychmüller, A.; Demir, H. V.

    2016-02-01

    We proposed and demonstrated the first account of large-area, semi-transparent, tandem photosensitive nanocrystal skins (PNSs) constructed on flexible substrates operating on the principle of photogenerated potential buildup, which avoid the need for applying an external bias and circumvent the current-matching limitation between junctions. We successfully fabricated and operated the tandem PNSs composed of single monolayers of colloidal water-soluble CdTe and CdHgTe nanocrystals (NCs) in adjacent junctions on a Kapton polymer tape. Owing to the usage of a single NC layer in each junction, noise generation was significantly reduced while keeping the resulting PNS films considerably transparent. In each junction, photogenerated excitons are dissociated at the interface of the semi-transparent Al electrode and the NC layer, with holes migrating to the contact electrode and electrons trapped in the NCs. As a result, the tandem PNSs lead to an open-circuit photovoltage buildup equal to the sum of those of the two single junctions, exhibiting a total voltage buildup of 128.4 mV at an excitation intensity of 75.8 μW cm-2 at 350 nm. Furthermore, we showed that these flexible PNSs could be bent over 3.5 mm radius of curvature and cut out in arbitrary shapes without damaging the operation of individual parts and without introducing any significant loss in the total sensitivity. These findings indicate that the NC skins are promising as building blocks to make low-cost, flexible, large-area UV/visible sensing platforms with highly efficient full-spectrum conversion.We proposed and demonstrated the first account of large-area, semi-transparent, tandem photosensitive nanocrystal skins (PNSs) constructed on flexible substrates operating on the principle of photogenerated potential buildup, which avoid the need for applying an external bias and circumvent the current-matching limitation between junctions. We successfully fabricated and operated the tandem PNSs composed of

  19. Flexible and fragmentable tandem photosensitive nanocrystal skins.

    PubMed

    Akhavan, S; Uran, C; Bozok, B; Gungor, K; Kelestemur, Y; Lesnyak, V; Gaponik, N; Eychmüller, A; Demir, H V

    2016-02-18

    We proposed and demonstrated the first account of large-area, semi-transparent, tandem photosensitive nanocrystal skins (PNSs) constructed on flexible substrates operating on the principle of photogenerated potential buildup, which avoid the need for applying an external bias and circumvent the current-matching limitation between junctions. We successfully fabricated and operated the tandem PNSs composed of single monolayers of colloidal water-soluble CdTe and CdHgTe nanocrystals (NCs) in adjacent junctions on a Kapton polymer tape. Owing to the usage of a single NC layer in each junction, noise generation was significantly reduced while keeping the resulting PNS films considerably transparent. In each junction, photogenerated excitons are dissociated at the interface of the semi-transparent Al electrode and the NC layer, with holes migrating to the contact electrode and electrons trapped in the NCs. As a result, the tandem PNSs lead to an open-circuit photovoltage buildup equal to the sum of those of the two single junctions, exhibiting a total voltage buildup of 128.4 mV at an excitation intensity of 75.8 μW cm(-2) at 350 nm. Furthermore, we showed that these flexible PNSs could be bent over 3.5 mm radius of curvature and cut out in arbitrary shapes without damaging the operation of individual parts and without introducing any significant loss in the total sensitivity. These findings indicate that the NC skins are promising as building blocks to make low-cost, flexible, large-area UV/visible sensing platforms with highly efficient full-spectrum conversion. PMID:26498487

  20. Tandem robot control system and method for controlling mobile robots in tandem

    DOEpatents

    Hayward, David R.; Buttz, James H.; Shirey, David L.

    2002-01-01

    A control system for controlling mobile robots provides a way to control mobile robots, connected in tandem with coupling devices, to navigate across difficult terrain or in closed spaces. The mobile robots can be controlled cooperatively as a coupled system in linked mode or controlled individually as separate robots.

  1. The Naples University 3 MV tandem accelerator

    SciTech Connect

    Campajola, L.; Brondi, A.

    2013-07-18

    The 3 MV tandem accelerator of the Naples University is used for research activities and applications in many fields. At the beginning of operation (1977) the main utilization was in the field of nuclear physics. Later, the realization of new beam lines allowed the development of applied activities as radiocarbon dating, ion beam analysis, biophysics, ion implantation etc. At present, the availability of different ion sources and many improvements on the accelerator allow to run experiments in a wide range of subjects. An overview of the characteristics and major activities of the laboratory is presented.

  2. Reduction of radial losses in tandem mirrors

    NASA Astrophysics Data System (ADS)

    Myra, J. R.; Dippolito, D. A.; Catto, P. J.

    1982-07-01

    The conditions for omnigenous magnetic fields are generalized to determine the fields which give the smallest mean square neoclassical step size consistent with given boundary conditions and constraints. This transport minimization produces less restrictive field configurations than omnigenity, and a wider class of practical applications is possible. An explicit set of ordinary differential equations is obtained for the transport minimizing vacuum fields in long thin tandem mirror geometry. The constraint, for these configurations no parallel current flows into the center cell (due to the Stupakov effect), is imposed naturally.

  3. HRIBF Tandem Accelerator Radiation Safety System Upgrade

    SciTech Connect

    Blankenship, J.L.; Juras, R.C.

    1998-11-04

    The HRIBF Tandem Accelerator Radiation Safety System was designed to permit experimenters and operations staff controlled access to beam transport and experiment areas with accelerated beam present. Neutron-Gamma detectors are mounted in eaeh area at points of maximum dose rate and the resulting signals are integrated by redundan~ circuitry; beam is stopped if dose rate or integrated dose exceeds established limits. This paper will describe the system, in use for several vears at the HRIBF, and discuss changes recently made to modernize the system and to make the system compliant with DOE Order 5480.25 and related ORNL updated safety rules.

  4. A Hybrid Approach To Tandem Cylinder Noise

    NASA Technical Reports Server (NTRS)

    Lockard, David P.

    2004-01-01

    Aeolian tone generation from tandem cylinders is predicted using a hybrid approach. A standard computational fluid dynamics (CFD) code is used to compute the unsteady flow around the cylinders, and the acoustics are calculated using the acoustic analogy. The CFD code is nominally second order in space and time and includes several turbulence models, but the SST k - omega model is used for most of the calculations. Significant variation is observed between laminar and turbulent cases, and with changes in the turbulence model. A two-dimensional implementation of the Ffowcs Williams-Hawkings (FW-H) equation is used to predict the far-field noise.

  5. Flute waves in a tandem mirror

    SciTech Connect

    Mikhailovskaya, L.V.

    1984-03-01

    Stability conditions are derived for flute waves in a short tandem mirror stabilized by end cells with a min B. The frequency spectrum of the flute waves is analyzed. Those conditions under which the resonant excitation of waves by ions and electrons must be taken into account are found. When end cells without a min B are added to a central mirror system, the system becomes destabilized as the result of resonant excitation of waves at a frequency near the precession frequency of ions having a finite energy distribution.

  6. Method of fabricating bifacial tandem solar cells

    SciTech Connect

    Wojtczuk, Steven J; Chiu, Philip T; Zhang, Xuebing; Gagnon, Edward; Timmons, Michael

    2014-10-07

    A method of fabricating on a semiconductor substrate bifacial tandem solar cells with semiconductor subcells having a lower bandgap than the substrate bandgap on one side of the substrate and with subcells having a higher bandgap than the substrate on the other including, first, growing a lower bandgap subcell on one substrate side that uses only the same periodic table group V material in the dislocation-reducing grading layers and bottom subcells as is present in the substrate and after the initial growth is complete and then flipping the substrate and growing the higher bandgap subcells on the opposite substrate side which can be of different group V material.

  7. HRIBF Tandem Accelerator Radiation Safety System Upgrade

    NASA Astrophysics Data System (ADS)

    Juras, R. C.; Blankenship, J. L.

    1999-06-01

    The HRIBF Tandem Accelerator Radiation Safety System was designed to permit experimenters and operations staff controlled access to beam transport and experiment areas with accelerated beam present. Neutron-Gamma detectors are mounted in each area at points of maximum dose rate and the resulting signals are integrated by redundant circuitry; beam is stopped if dose rate or integrated dose exceeds established limits. This paper will describe the system, in use for several years at the HRIBF, and discuss changes recently made to modernize the system and to make the system compliant with DOE Order 5480.25 and related ORNL updated safety rules.

  8. Progress in the tandem mirror program

    SciTech Connect

    Fowler, T.K.; Borchers, R.R.

    1981-09-13

    Experimental results in TMX have confirmed the basic principles of the tandem-mirror concept. A center-cell particle confinement parameter eta tau approx. 10/sup 11/ cm/sup -3/ s has been obtained at ion temperatures around 100 eV, which is a hundred-fold improvement over single mirrors at the same temperatures. For TMX these results have been obtained at peak beta values in the center cell in the range 10 to 40%, not yet limited by MHD activity; and ion-cyclotron resonant heating (ICRH) in the Phaedrus tandem-mirror experiment has produced beta values approx. 25%, which is several times the ideal MHD limit for that device. In addition, it has been demonstrated that the end fan chambers of TMX simultaneously isolate the hot electrons from the end walls, provide adequate pumping and conveniently dispose of the exhaust plasma energy either by thermal deposition on the end wall or by direct conversion to electricity (at 48% efficiency in agreement with calculations). Also, evidence was obtained for inherent divertor action in TMX, presumably in part responsible for the observed low impurity level (<0.5% low-Z ions in the center cell).

  9. Tandem mass spectrometry for sequencing proanthocyanidins.

    PubMed

    Li, Hui-Jing; Deinzer, Max L

    2007-02-15

    Proanthocyanidins (PAs) are a group of bioflavonoids consisting of oligomers based on catechin monomeric units. These polyphenolic compounds are widely distributed in higher plants and are an integral part of the human diet. A sensitive LC-tandem mass spectrometric (LC/ESI-MS(n)) method in the positive ion mode for sequencing these ubiquitous and highly beneficial antioxidants is described. The hydroxylation patterns and interflavanoid linkage for A- and B-type PAs were determined by fragment ions derived from a retro-Diels-Alder (RDA) fission, heterocyclic ring fission (HRF), a novel benzofuran-forming (BFF) fission described here for the first time, and a quinone methide (QM) fission. The subunit sequence of the PAs was determined by diagnostic ions derived from HRF/RDA fission, HRF/BFF fission, and RDA/HRF fission together with QM fission. A total of 26 PAs were reliably sequenced by the newly established tandem mass spectrometric protocol. It is shown that the protocol based on a combination of these different fragmentation patterns allows for uniquely identifying PA oligomers. PMID:17297981

  10. High-sensitivity mass spectrometry with a tandem accelerator

    SciTech Connect

    Henning, W.

    1983-01-01

    The characteristic features of accelerator mass spectrometry are discussed. A short overview is given of the current status of mass spectrometry with high-energy (MeV/nucleon) heavy-ion accelerators. Emphasis is placed on studies with tandem accelerators and on future mass spectrometry of heavier isotopes with the new generation of higher-voltage tandems.

  11. A tandem-based compact dual-energy gamma generator

    SciTech Connect

    Persaud, A.; Kwan, J.W.; Leitner, M.; Leung, K.N.; Ludewigt, B.; Tanaka, N.; Waldron, W.; Wilde, S.; Antolak, A.J.; Morse, D.H.; Raber, T.

    2009-11-11

    A dual-energy tandem-type gamma generator has been developed at E.O. Lawrence Berkeley National Laboratory and Sandia National Laboratories. The tandem accelerator geometry allows higher energy nuclear reactions to be reached, thereby allowing more flexible generation of MeV-energy gammas for active interrogation applications.

  12. Thermal-barrier production and indentification in a tandem mirror

    SciTech Connect

    Grubb, D.P.; Allen, S.L.; Casper, T.A.; Clauser, J.F.; Coensgen, F.H.; Correll, D.L.; Cummins, W.F.; Damm, C.C.; Foote, J.H.; Goodman, R.K.; Hill, D.N.; Hooper,Jr., E.B.; Hornady, R.S.; Hunt, A.L.; Kerr, R.G.; Leppelmeier, G.W.; Marilleau, J.; Moller, J.M.; Molvik, A.W.; Nexsen, W.E.; Pickles, W.L.; Porter, G.D.; Poulsen, P.; Silver, E.H.; Simonen, T.C.; Stallard, B.W.; Turner, W.C.; Hsu, W.L.; Yu, T.L.; Barter, J.D.; Christensen, T.; Dimonte, G.; Romesser, T.W.; Ellis, R.F.; James, R.A.; Lasnier, C.J.; Berzins, L.V.; Carter, M.R.; Clower, C.A.; Failor, B.H.; Falabella, S.; Flammer, M.; Nash, T.

    1984-08-20

    In thermal-barrier experiments in the tandem mirror experiment upgrade axial confinement times of 50 to 100 ms have been achieved. During enhanced confinement we measured the thermal-barrier potential profile using a neutral-particle-beam probe. The experimental data agree qualitatively and quantitatively with the theory of thermal-barrier formation in a tandem mirror.

  13. 14 CFR 105.45 - Use of tandem parachute systems.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Use of tandem parachute systems. 105.45... (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES PARACHUTE OPERATIONS Parachute Equipment and Packing § 105.45 Use of tandem parachute systems. (a) No person may conduct a parachute operation using a...

  14. 14 CFR 105.45 - Use of tandem parachute systems.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Use of tandem parachute systems. 105.45... (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES PARACHUTE OPERATIONS Parachute Equipment and Packing § 105.45 Use of tandem parachute systems. (a) No person may conduct a parachute operation using a...

  15. 14 CFR 105.45 - Use of tandem parachute systems.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Use of tandem parachute systems. 105.45... (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES PARACHUTE OPERATIONS Parachute Equipment and Packing § 105.45 Use of tandem parachute systems. (a) No person may conduct a parachute operation using a...

  16. 14 CFR 105.45 - Use of tandem parachute systems.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Use of tandem parachute systems. 105.45... (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES PARACHUTE OPERATIONS Parachute Equipment and Packing § 105.45 Use of tandem parachute systems. (a) No person may conduct a parachute operation using a...

  17. Tandem-type pulse tube refrigerator without reservoir

    NASA Astrophysics Data System (ADS)

    Ki, Taekyung; Jeong, Sangkwon; Ko, Junseok; Park, Jiho

    2015-12-01

    In this paper, a tandem-type pulse tube refrigerator without a reservoir is discussed and investigated. For its practical application a tandem-type compressor is designed to generate two pulsating pressure waves with opposite phases, simultaneously. A tandem-type pulse tube refrigerator consists of a tandem-type compressor and two identical pulse tube refrigerators. The two identical pulse tube refrigerators share the same heat exchangers and one can be connected with the other by an inertance tube without a reservoir. In this proposed configuration, the mechanical vibration and temperature oscillations in the cold-end heat exchanger can be internally suppressed due to its intrinsic opposite-characteristic operation. To examine the quantitative evaluation of the tandem feature which does not require a reservoir in the pulse tube, an evolutionary approach has been attempted. A general structure of a pulse tube refrigerator is modified into tandem Stirling-type and GM-type machines and the transformed configuration has been simulated for tandem operation. The simulation results clearly demonstrate that a properly designed tandem-type pulse tube refrigerator without a reservoir can function favorably.

  18. The physiological effects of cycling on tandem and single bicycles

    PubMed Central

    Seifert, J; Bacharach, D; Burke, E; Langenfeld, M; Snyder, A

    2003-01-01

    Objective: The purpose of this field study was to compare the physiological responses from cycling on a tandem road bicycle to those from cycling on a single road bicycle. Methods: Nine pairs of experienced, recreational tandem cyclists rode a tandem or their single bicycle for 5 min at each velocity of 19.3, 22.5, 25.8, and 29.0 kph on a flat, paved surface. Heart rate (HR), rating of perceived exertion (RPE), and lactic acid (LA) data were collected after each interval. Results: Riding a tandem resulted in lower HR, RPE, and LA mean values across the four velocities compared to the single bicycle. Mean (SD) HR, RPE, and LA for tandem and single bicycles were 126 (20.7) v 142 (20.1) bpm, 10.1 (1.7) v 11.3 (2.6), and 1.46 (1.0) mM/L v 2.36 (1.7) mM/L, respectively. No position differences were observed between the captain and stoker (front and rear positions) when both were on the tandem. Stokers had significantly lower HR, LA, and RPE values when they rode a tandem compared to a single bicycle. No statistical differences were observed between bicycles for the captains. When on the single bicycle, captains exhibited significantly lower HR, RPE, and LA values than stokers. Conclusion: Cycling on a tandem resulted in lower physiological stress than when cycling at the same velocity on a single bicycle. Cyclists were able to ride from 4.8–8.0 kph faster on a tandem than on a single bicycle at similar physiological stress. Apparently, stokers can add to power output on a tandem without adding significantly to wind resistance. PMID:12547743

  19. Electronic Tandem Language Learning (eTandem): A Third Approach to Second Language Learning for the 21st Century

    ERIC Educational Resources Information Center

    Cziko, Gary A.

    2004-01-01

    Tandem language learning occurs when two learners of different native languages work together to help each other learn the other language. First used in face-to-face contexts, Tandem is now increasingly being used by language-learning partners located in different countries who are linked via various forms of electronic communication, a context…

  20. Axisymmetric Tandem Mirrors: Stabilization and Confinement Studies

    SciTech Connect

    Post, R F; Fowler, T K; Bulmer, R; Byers, J; Hua, D; Tung, L

    2004-07-15

    The 'Kinetic Stabilizer' has been proposed as a means of MHD stabilizing an axisymmetric tandem mirror system. The K-S concept is based on theoretical studies by Ryutov, confirmed experimentally in the Gas Dynamic Trap experiment in Novosibirsk. In the K-S beams of ions are directed into the end of an 'expander' region outside the outer mirror of a tandem mirror. These ions, slowed, stagnated, and reflected as they move up the magnetic gradient, produce a low-density stabilizing plasma. At the Lawrence Livermore National Laboratory we have been conducting theoretical and computational studies of the K-S Tandem Mirror. These studies have employed a low-beta code written especially to analyze the beam injection/stabilization process, and a new code SYMTRAN (by Hua and Fowler) that solves the coupled radial and axial particle and energy transport in a K-S TM. Also, a 'legacy' MHD stability code, FLORA, has been upgraded and employed to benchmark the injection/stabilization code and to extend its results to high beta values. The FLORA code studies so far have confirmed the effectiveness of the K-S in stabilizing high-beta (40%) plasmas with stabilizer plasmas the peak pressures of which are several orders of magnitude smaller than those of the confined plasma. Also the SYMTRAN code has shown D-T plasma ignition from alpha particle energy deposition in T-M regimes with strong end plugging. Our studies have confirmed the viability of the K-S-T-M concept with respect to MHD stability and radial and axial confinement. We are continuing these studies in order to optimize the parameters and to examine means for the stabilization of possible residual instability modes, such as drift modes and 'trapped-particle' modes. These modes may in principle be controlled by tailoring the stabilizer plasma distribution and/or the radial potential distribution. In the paper the results to date of our studies are summarized and projected to scope out possible fusion-power versions of the K

  1. Axisymmetric Tandem Mirrors: Stabilization and Confinement Studies

    SciTech Connect

    Post, R.F.; Fowler, T.K.; Bulmer, R.; Byers, J.; Hua, D.; Tung, L.

    2005-01-15

    The 'Kinetic Stabilizer' has been proposed as a means of MHD stabilizing an axisymmetric tandem mirror system. The K-S concept is based on theoretical studies by Ryutov, confirmed experimentally in the Gas Dynamic Trap experiment in Novosibirsk. In the K-S beams of ions are directed into the end of an 'expander' region outside the outer mirror of a tandem mirror. These ions, slowed, stagnated, and reflected as they move up the magnetic gradient, produce a low-density stabilizing plasma.At the Lawrence Livermore National Laboratory we have been conducting theoretical and computational studies of the K-S Tandem Mirror. These studies have employed a low-beta code written especially to analyze the beam injection/stabilization process,and a new code SYMTRAN (by Hua and Fowler)that solves the coupled radial and axial particle and energy transport in a K-S T-M. Also, a 'legacy' MHD stability code, FLORA, has been upgraded and employed to benchmark the injection/stabilization code and to extend its results to high beta values.The FLORA code studies so far have confirmed the effectiveness of the K-S in stabilizing high-beta (40%) plasmas with stabilizer plasmas the peak pressures of which are several orders of magnitude smaller than those of the confined plasma.Also the SYMTRAN code has shown D-T plasma ignition from alpha particle energy deposition in T-M regimes with strong end plugging.Our studies have confirmed the viability of the K-S T-M concept with respect to MHD stability and radial and axial confinement. We are continuing these studies in order to optimize the parameters and to examine means for the stabilization of possible residual instability modes, such as drift modes and 'trapped-particle' modes. These modes may in principle be controlled by tailoring the stabilizer plasma distribution and/or the radial potential distribution.In the paper the results to date of our studies are summarized and projected to scope out possible fusion-power versions of the K-S T-M.

  2. Negative deuterium ions for tandem mirror next step and tandem mirror reactors

    SciTech Connect

    Hamilton, G.W.

    1980-09-25

    Recent designs for mirror fusion reactors with good power balance include ambipolar potential plugs to reduce end losses and thermal barriers to maintain a difference in electron temperature between the large-volume central cell plasma and the confining end plugs. These designs led to several new requirements for D/sup 0/ neutral beams derived from negative ions at energies of 150 to 200 keV and possibly higher. Such beams are required for injection of fat ions into the plugs and the barrier and for charge-exchange pumping of thermal ions diffusing into the barrier. Negative ions are preferred for these purposes because of their relatively high efficiency of neutralization and their high purity of single-energy D/sup -/. Examples of injector designs for Tandem Mirror Next Step (TMNS) and Tandem Mirror Reactors (TMR) are presented.

  3. Recent Results from KMAX tandem mirror experiment

    NASA Astrophysics Data System (ADS)

    Sun, Xuan; Luo, M.; Zhang, Q.; Lin, M.; Shi, P.

    2015-11-01

    KMAX, Keda Mirror with AXisymmeticity, is a tandem mirror machine with a length of ~ 10 meters and diameters of 1.2 meters in the central cell and 0.3 meters in the mirror throat. As a versatile plasma experimental platform, KMAX is currently conducting experiments on the Alfven wave launching, electrode biasing, radio frequency heating and etc. The latest results will be presented. In the experiment of Alfven wave launching, we observed the shear Alfven waves decay into the forward and backward propagating compressional waves. And in the bias experiment we successfully extracted plasma current up to 0.5kA with biasing voltage of ~ 1kV. During biasing, the plasma density and temperature have siginificantly increasing. Preliminary results on the radio frequency heating will also be presented.

  4. Parametric systems analysis for tandem mirror hybrids

    SciTech Connect

    Lee, J.D.; Chapin, D.L.; Chi, J.W.H.

    1980-09-01

    Fusion fission systems, consisting of fissile producing fusion hybrids combining a tandem mirror fusion driver with various blanket types and net fissile consuming LWR's, have been modeled and analyzed parametrically. Analysis to date indicates that hybrids can be competitive with mined uranium when U/sub 3/O/sub 8/ cost is about 100 $/lb., adding less than 25% to present day cost of power from LWR's. Of the three blanket types considered, uranium fast fission (UFF), thorium fast fission (ThFF), and thorium fission supressed (ThFS), the ThFS blanket has a modest economic advantage under most conditions but has higher support ratios and potential safety advantages under all conditions.

  5. Magnetic alignment of the Tara tandem mirror

    SciTech Connect

    Post, R.S.; Coleman, J.W.; Irby, J.H.; Olmstead, M.M.; Torti, R.P.

    1985-06-01

    Techniques developed for the alignment of high-energy accelerators have been applied to the alignment of the Tara tandem mirror magnetic confinement device. Tools used were: a transit/laser surveyor's system for establishing an invariant reference; optical scattering from ferromagnetic crystallites for establishing magnetic centers in the quadrupole anchor/transition modules; an electron-optical circle-generating wand for alignment of the solenoidal plug and central cell modules; and four differently configured electron emissive probes, including a 40-beam flux mapping e gun, for testing the alignment of the coils under vacuum. Procedures are outlined, and results are given which show that the magnetic axes of the individual coils in the Tara set have been made colinear with each other and with the reference to within +- 1.0 mm over the length of the machine between the anchor midplanes.

  6. Catalyzed deuterium fueled tandem mirror reactor assessment

    SciTech Connect

    Dobrott, D.

    1985-01-01

    This study was part of a Department of Energy supported alternate fusion fuels program at Science Applications International Corp. The purpose of this portion of the study is to perform an assessment of a conceptual tandem mirror reactor (TMR) that is fueled by the catalyzed-deuterium (Cat-d) fuel cycle with respect to the physics, technology, safety, and cost. Achievable stable betas and magnet configurations are found to be comparable for the Cat-d and d-t fueled TMR. A comparison with respect to cost, reactor performance, and technology requirements for a Cat-d fueled reactor and a comparable d-t fueled reactor such as MARS is also made.

  7. Electrospray and tandem mass spectrometry in biochemistry.

    PubMed Central

    Griffiths, W J; Jonsson, A P; Liu, S; Rai, D K; Wang, Y

    2001-01-01

    Over the last 20 years, biological MS has changed out of all recognition. This is primarily due to the development in the 1980s of 'soft ionization' methods that permit the ionization and vaporization of large, polar, and thermally labile biomolecules. These developments in ionization mode have driven the design and manufacture of smaller and cheaper mass analysers, making the mass spectrometer a routine instrument in the biochemistry laboratory today. In the present review the revolutionary 'soft ionization' methods will be discussed with particular reference to electrospray. The mass analysis of ions will be described, and the concept of tandem MS introduced. Where appropriate, examples of the application of MS in biochemistry will be provided. Although the present review will concentrate on the MS of peptides/proteins and lipids, all classes of biomolecules can be analysed, and much excellent work has been done in the fields of carbohydrate and nucleic acid biochemistry. PMID:11311115

  8. Protein Sequencing with Tandem Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Ziady, Assem G.; Kinter, Michael

    The recent introduction of electrospray ionization techniques that are suitable for peptides and whole proteins has allowed for the design of mass spectrometric protocols that provide accurate sequence information for proteins. The advantages gained by these approaches over traditional Edman Degradation sequencing include faster analysis and femtomole, sometimes attomole, sensitivity. The ability to efficiently identify proteins has allowed investigators to conduct studies on their differential expression or modification in response to various treatments or disease states. In this chapter, we discuss the use of electrospray tandem mass spectrometry, a technique whereby protein-derived peptides are subjected to fragmentation in the gas phase, revealing sequence information for the protein. This powerful technique has been instrumental for the study of proteins and markers associated with various disorders, including heart disease, cancer, and cystic fibrosis. We use the study of protein expression in cystic fibrosis as an example.

  9. Dual analyte detection using tandem flash luminescence.

    PubMed

    Adamczyk, Maciej; Moore, Jeffrey A; Shreder, Kevin

    2002-02-11

    A heterogeneous, dual analyte-binding assay which makes use of the flash luminescence from both aequorin and an acridinium-9-carboxamide label is presented. The signal generating species were triggered both differentially and sequentially using Ca(2+) followed by basic peroxide. Both signals were resolved readily using a single photomultiplier tube without the need for multiwavelength detection. To demonstrate the tandem luminescence concept in a model assay system, dose-response curves for two analytes, biotinylated BSA and myoglobin, were generated using a competitive binding format. Because of the relatively short assay time and the well-resolved signals, this format will be useful in the development of dual analyte high-throughput assays. PMID:11814805

  10. Recent Activities in Tandem, Booster and TRIAC at Tokai

    SciTech Connect

    Ishii, Tetsuro; Matsuda, Makoto; Kabumoto, Hiroshi; Osa, Akihiko

    2009-05-04

    Present status and recent developments of the tandem accelerator, superconducting booster, and radioactive nuclear beam accelerator TRIAC are presented. The terminal voltage of the tandem accelerator reached 19.1 MV by replacing acceleration tubes. The multi-charged positive-ion injector was installed in the terminal of the tandem accelerator, supplying noble-gas ions. A superconducting cavity for low-velocity ions was developed. Radioactive nuclear beams of {sup 8}Li, {sup 123}In, and {sup 143}Ba were accelerated. Recent experimental results of nuclear physics are also reported.